instruction:
In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
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Context: Although the echolucent plaque in carotid stenosis is associated with future ischemic stroke, the predictive value of echogenicity in small and medium size carotid plaques on vascular events has not been thoroughly examined. Thus, we prospectively tested the hypothesis that plaque echogenicity of carotid atheroma can predict the future total cardiovascular events in patients with vascular risk factors.', 'Ultrasound assessment of carotid intima-media complex thickness (IMT) and plaque echogenicity using integrated backscatter (IBS) analysis was performed in 596 patients aged 40 or more, with any history of vascular events or with at least 1 risk factor, who were enrolled between 2001 and 2006 in the Osaka Follow-up Study for Carotid Atherosclerosis, part 2 (OSACA2). We followed the incidence of total cardiovascular events including cerebrovascular events, coronary heart disease (CHD), and peripheral artery disease (PAD) for 6.4 years. We divided the patients into two groups according to the IBS index above (echorich plaques) and under (echolucent plaque) the median value, and calculated the hazard ratios (HR) of the echolucent group compared with the echogenic group in the risk of cardiovascular events.', 'Among 596 patients, carotid stenosis was found only in 87 patients. During the follow-up period, we observed 121 cardiovascular events including 63 cerebrovascular events, 45 CHD cases, and 13 PAD cases. The patients with incident cardiovascular events had larger plaque thickness and lower IBS index than those without incident vascular events. The relative risk of vascular events for echolucent versus echorich plaques was 1.45 (95% confidence interval [CI] 0.99-2.13, p = 0.058) after adjustment for risk factors and plaque thickness. In patients with plaque size above the median value (>2.1 mm), the relative risk of vascular events for echolucent plaques was 1.72 (95% CI 1.06-2.85, p = 0.029), but this association was not observed in patients with plaque size <2.0 mm.\Question: Does echogenicity of medium-to-large carotid plaques predict future vascular events?
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The association between echogenicity of carotid plaque and incident vascular events is dependent on the plaque size. Echolucent medium-to-large plaques, but not small plaques, are associated with the risk of future total cardiovascular events. This finding suggests that measurement of echolucency in medium-to-large carotid plaques may improve selection of patients at high risk for total vascular events.

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Context: Dipeptidyl peptidase-4 (DPP4) was recently proposed as a novel adipokine linked to insulin resistance (IR). As IR represents a cluster of disorders in hepatic and muscle cell insulin signalisation, we aimed to assess the possible correlation between fasting serum DPP4 activity, IR and liver enzymes in order to elucidate the question of hepatic contribution to serum DPP4 activity.', 'This cross-sectional study comprised 44 T1DM patients aged 18 to 65years. IR was estimated using the equation derived from euglycemic-hyperinsulinemic clamp studies-estimated glucose disposal rate (eGDR). DPP4 serum activity was determined spectrophotometrically as a rate of cleavage of 7-amino-4-methyl coumarin (AMC) from H-Gly-Pro-AMC. The patients were divided into two groups according to the mean value of fasting serum DPP4 activity (31.42U/L).', 'The group with lower fasting serum DPP4 activity had lower mean rate of liver biomarkers alanine aminotransferase (ALT) (p=0.001) and aspartate aminotransferase (AST) (p=0.002) while higher eGDR (p=0.003) compared to group with higher DPP4 activity. DPP4 activity showed positive correlation with AST (r=0.358, p=0.017) and ALT (r=0.364, p=0.015) while negative correlation with eGDR (r=-0.612, p<0.001). ALT remained positively associated with fasting serum DPP4 activity after controlling for age, gender, diabetes duration, the use of statins and antihypertensives (p=0.025).\Question: Is fasting serum dipeptidyl peptidase-4 activity independently associated with alanine aminotransferase in type 1 diabetic patients?
answer:
Fasting serum DPP4 activity might be associated with hepatic IR in T1DM patients and a part of soluble DPP4 activity might be of a hepatic origin. Further study investigation is warranted to elucidate this topic.

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Context: Some cases with non-alcoholic fatty liver disease (NAFLD), particularly non-alcoholic steatohepatitis (NASH), can ultimately progress to liver cirrhosis. However, studies to clarify factors predictive of histological change in patients with NASH remain scarce. Our aim is to determine predictors of histological progression in Japanese patients with biopsy-proven NASH.', 'This retrospective cohort study enrolled 52 patients with NASH who underwent serial liver biopsies. Histological evaluation included NAFLD activity score (NAS) and liver fibrosis. The median interval between initial and second liver biopsies was 968days. An alanine aminotransferase (ALT) response was defined as a decrease of 30% or more from baseline.', 'Of 52 patients, NAS was ameliorated in 30.8%, deteriorated in 30.8% and remained unchanged in 38.4%. Liver fibrosis was improved in 25.0% of patients, progressed in 25.0% and remained stable in 50.0%. Multivariate analysis identified ALT non-response as a predictor of deterioration of NAS (hazard ratio [HR], 5.85; P=0.031) and progression of liver fibrosis (HR, 4.50; P=0.029). The mean annual rate of fibrosis was 0.002 stages/year overall, increasing to 0.15 stages/year in ALT non-responders.\Question: Does serum alanine aminotransferase predict the histological course of non-alcoholic steatohepatitis in Japanese patients?
answer:
A lack of reduction in serum ALT level by at least 30% from baseline was a predictor for histological progression in patients with NASH. Serum ALT level is a better predictor of histological change than insulin resistance or bodyweight and can be a valid index in treatment. Serum ALT should be strictly controlled to prevent liver histological progression in patients with NASH.