Preparation of enzyme-responsive composite nanocapsules with sodium carboxymethyl cellulose to improve the control effect of root-knot nematode disease.

Developing an efficient drug delivery system to mitigate the harm caused by root-knot nematodes is crucial. In this study, enzyme-responsive release abamectin nanocapsules (AVB1a NCs) were prepared using 4, 4-diphenylmethane diisocyanate (MDI) and sodium carboxymethyl cellulose as response release factors. The results showed that the average size (D50) of the AVB1a NCs was 352 nm, and the encapsulation efficiency was 92 %. The median lethal concentration (LC50) of AVB1a NCs for Meloidogyne incognita activity was 0.82 mg L-1. Moreover, AVB1a NCs improved the permeability of AVB1a to root-knot nematodes and plant roots and the horizontal and vertical soil mobility. Furthermore, AVB1a NCs greatly reduced the adsorption of AVB1a by the soil compared to AVB1a emulsifiable concentrate (EC), and the effect of the AVB1a NCs on controlling root-knot nematode disease was increased by 36 %. Compared to the AVB1a EC, the pesticide delivery system significantly reduced the acute toxicity to the soil biological earthworms by approximately 16 times that of the AVB1a and had a lower overall impact on the soil microbial communities. This enzyme-responsive pesticide delivery system had a simple preparation method, excellent performance, and high level of safety, and thus has great application potential for plant diseases and insect pests control.

[Expression of SIRT1 in right auricle tissues and the relationship with oxidative stress in patients with atrial fibrillation].

AIM: To observe the expression of mammalian sirtuin 1 (SIRT1) in right auricle tissues in patients presenting with atrial fibrillation (AF) and make clear the relationship between SIRT1 expression and oxidative stress. METHODS: A total of 38 patients with rheumatic heart disease were divided into 2 groups: AF group (AF lasted more than 6 months, n=25) and SR (sinus rhythm) group (n=13). The expression of SIRT1 in right auricle tissues harvested during heart operations was detected by immunohistochemistry. Oxidative stress was estimated by the amounts of malondialdehyde (MDA) and metallothionein (MT) and the activity of superoxide dismutase (SOD) which were detected using thiobarbituric acid reaction (TBA), enzyme-linked immunosorbent assay (ELISA) and xanthine oxidase assay, respectively. RESULTS: Compared with the SR group, the expression of SIRT1 protein in the atrium significantly increased in AF group [P<0.05, (45.8±4.03)% vs (19.7±2.54)%]. In AF group, MDA was (7.24±1.05) nmol/mg, SOD (1034.25±84.32) U/mg and MT (7.21±1.46) µg/g, all being significantly higher than those in SR group[P<0.05, MDA: (3.01±0.47) nmol/mg; SOD: (723.63±65.23) U/mg; MT: (4.31±1.23) µg/g]. Spearman correlation indicated that the expression of SIRT1 had a significantly negative correlation with the amounts of MDA and MT and the activity of SOD (P<0.05, r=-0.447, -0.521, -0.394, respectively). CONCLUSION: The expression of SIRT1 increased in patients with AF. SIRT1 maybe effects the AF by means of inhibiting the process of oxidative stress.

Overexpression of activated nuclear factor-kappa B in aorta of patients with coronary atherosclerosis.

BACKGROUND: Inflammation is an established risk factor for atherosclerosis. In an inflammatory state, nuclear factor-kappa B (NF-kappaB) is frequently activated as a key transcription activator for the downstream responses. HYPOTHESIS: The aim of this study was to investigate the changes of NF-kappaB in the aorta of patients with coronary atherosclerosis and its association with atherosclerotic risk factors. METHODS: From 2004 to 2005, we collected a small piece of ascending aorta in the bypass procedure from patients (n = 31) undergoing coronary artery bypass graft (CABG) surgery. The expression of NF-kappaB was determined by immunohistochemistry, and its transcriptional activity was evaluated by electrophoretic mobility shift assay. Celiac aortic tissues from 4 subjects without known atherosclerosis through the kidney donation program were taken as control. RESULTS: NF-kappaB was detectable in aortas from CABG patients with the transcriptional activities significantly increased. The relative level of aortic NF-kappaB expression was elevated in patients who were smokers or with hypertension. Spearman correlation revealed that aortic NF-kappaB expression had significant correlation with coronary severity scores (Gensini score, r = 0.608, P < .05). The NF-kappaB expression was positively correlated with the levels of blood glucose, low-density lipoprotein cholesterol, lipoprotein(a), total cholesterol, and non-high-density lipoprotein cholesterol (P < .05); but negatively correlated with high-density lipoprotein cholesterol (P < .05). CONCLUSIONS: Our study demonstrates a highly activated NF-kappaB in aortas from patients with coronary atherosclerosis, which may reflect overall arterial overinflammatory status. The findings of hyperactive NF-kappaB in aortas may provide a diagnostic parameter for the inflammation that is associated with and may cause atherosclerosis.