Kinetic analysis of inhibition of α-glucosidase by leaf powder from Morus australis and its component iminosugars.

Mulberry leaves contain iminosugars, such as 1-deoxynojirimycin (1-DNJ), fagomine, and 2-O-α-D-galactopyranosyl deoxynojirimycin (GAL-DNJ) that inhibit α-glucosidase. In this study, we quantified iminosugars in Morus australis leaves and made the kinetic analysis in the hydrolysis of maltose by α-glucosidase. By LC-MS/MS, the concentrations of 1-DNJ, fagomine, and GAL-DNJ in the powdered leaves were 4.0, 0.46, and 2.5 mg/g, respectively, and those in the roasted ones were 1.0, 0.24, and 0.73 mg/g, respectively, suggesting that the roasting process degraded iminosugars. Steady-state kinetic analysis revealed that the powdered and roasted leaves exhibited competitive inhibition. At pH 6.0 at 37ºC, the IC50 values of the extracts from the boiled powdered or roasted leaves were 0.36 and 1.1 mg/mL, respectively. At the same condition, the IC50 values of 1-DNJ, fagomine, and GAL-DNJ were 0.70 µg/mL, 0.18 mg/mL, and 2.9 mg/mL, respectively. These results suggested that in M. australis, 1-DNJ is a major inhibitor of α-glucosidase. ABBREVIATIONS: 1-DNJ: 1-deoxynojirimycin; GAL-DNJ: 2-O-α-D-galactopyranosyl-DNJ.

[Change in Serum Levels of New Hepatic Fibrosis Marker "Mac-2 Binding Protein Glycosylation isomer (M2BPGi)" in Patients with Chronic Hepatitis C during the Treatment of Pegylated Interferon and Ribavirin].

The sustained virological response (SVR) rate in the patients with HCV has currently reached to 90% by the progression of anti-viral therapy. However, several reports demonstrated that hepatocellular carcinoma develops even in the patients with SVR. It is widely accepted that liver fibrosis plays a pivotal role in hepatocellular carcinogenesis. Thus, an accurate staging for liver fibrosis is necessary to improve long-term prognosis of hepatitis C patients. Recently, Mac-2 binding protein glycosylation isomer (M2BPGi) was identified as a novel hepatic fibrosis marker. In the present study, we compared the value of M2BPGi in serum before and after the anti-viral therapy in hepatitis C patients. The value of M2BPGi in patients with F2, F3, or F4 stagings was significantly higher than that in F1 staging. Moreover, the value of M2BPGi significantly decreased after the treatment with pegylated interferon plus ribavirin similarly to other liver fibrosis-related markers. In addition, the value of M2BPGi in patients with SVR was significantly decreased after the anti-viral therapy (P < 0.0001). The reduction of M2BPGi in SVR patients was thought to reflect the improvement of liver fibrosis, in conjunction with the reduction of viral load, after the treatment. In conclusion, the measurement of M2BPGi in serum might be useful in monitoring the improvement of liver fibrosis by anti-viral therapy.

Sitting maneuver to uncover latent left ventricular outflow tract obstruction in patients without hypertrophic cardiomyopathy.

BACKGROUND: Left ventricular outflow tract obstruction [LVOTO; pressure gradient (PG) ≥30 mmHg] is observed in some patients without hypertrophic cardiomyopathy (HCM), and it may develop especially in older patients without HCM (non-HCM). The aim of this study is to investigate if the Valsalva or an upright sitting maneuver can unveil latent LVOTO in patients with non-HCM. METHODS: A total of 33 non-HCM patients with a late peaking or dagger-shaped pulsed Doppler waveform of the LVOT and PG <30 mmHg were included. The Doppler flow velocity of the LVOT was measured at rest, after the Valsalva and a sitting maneuver. Peak PG of ≥30 mmHg after either maneuver was defined as latent LVOTO. The angle between the left ventricular septum and the aorta in the parasternal long-axis view and the apical three-chamber view was measured. RESULTS: Twenty (61 %) of the 33 patients (mean age 74 ±â€¯9 years) were diagnosed with latent LVOTO. Of these, five (25 %) patients were diagnosed after both the Valsalva and sitting maneuver, and 15 (75 %) were diagnosed only after the sitting maneuver. The latent LVOTO group had a significantly smaller angle than the no-LVOTO group between the ventricular septum and the aorta in the parasternal long axis views (107 ±â€¯8° vs. 117 ±â€¯8°, p < 0.01). CONCLUSION: The sitting maneuver is better than the Valsalva maneuver in unveiling latent LVOTO in older, non-HCM patients.

Assessment of sarcopenia and malnutrition using estimated GFR ratio (eGFRcys/eGFR) in hospitalised adult patients.

BACKGROUND & AIMS: The aim of our study was to clarify whether the eGFR ratio (eGFRcys/eGFR) is appropriate for evaluating muscle mass as an alternative method to bioelectrical impedance analysis (BIA). We also investigated the accuracy and usefulness of the eGFR ratio in the diagnosis of sarcopenia and malnutrition. METHODS: Serum creatinine (Cre) and cystatin C (Cys) were measured, and the eGFR ratio was calculated among 151 hospitalised patients (65 men and 86 women). The correlation between the eGFR ratio and skeletal muscle mass index (SMI) measured using BIA was analysed. Sarcopenia was diagnosed using the European Working Group on Sarcopenia in Older People (EWGSOP) 2 and Asian Working Group for Sarcopenia (AWGS) 2019 algorithms, while malnutrition was diagnosed using the Global Leadership Initiative on Malnutrition (GLIM) criteria. The diagnostic accuracy of the calculated SMI (Cal-SMI) based on the eGFR ratio was analysed. RESULTS: A moderate correlation between the eGFR ratio and muscle mass was observed. For the diagnosis of sarcopenia using the EWGSOP2 and Cal-SMI using the eGFR ratio, the sensitivity was 0.952 (95% confidence interval [CI] 0.892-0.984); specificity, 0.848 (95% CI, 0.711-0.937); and diagnostic accuracy, 0.921 (95% CI, 0.865-0.958). For the diagnosis of malnutrition using GLIM, the sensitivity was 0.980 (95% CI 0.929-0.998); specificity, 0.788 (95% CI 0.653-0.889); and diagnostic accuracy, 0.914 (95% CI 0.857-0.953). CONCLUSIONS: An accurate diagnosis of sarcopenia using the EWGSOP2 and AWGS2019, and an accurate diagnosis of malnutrition using GLIM, was made using the eGFR ratio. The eGFR ratio may be a suitable alternative when BIA cannot be used.