Mutagenicity and preclinical safety assessment of the aqueous extract of Clinacanthus nutans leaves

Context: Clinacanthus nutans (CN) is used traditionally for treating various illnesses. Robust safety data to support its use is lacking. Objective: To evaluate the adverse effects of aqueous extract of CN leaves (AECNL). Materials and methods: The oral toxicity of the AECNL was tested following Organisation for Economic Co-operation and Development (OECD) guidelines. Mutagenicity (Ames test) of AECNL was evaluated using TA98 and TA100 Salmonella typhimurium strains. Results: No mortality or morbidity was found in the animals upon single and repeated dose administration. However, significant body weight loss was observed at 2000?mg/kg during sub-chronic (90 d) exposure. In addition, increased eosinophil at 500?mg/kg and decreased serum alkaline phosphatase levels at 2000?mg/kg were observed in male rats. Variations in glucose and lipid profiles in treated groups were also observed compared to control. Ames test revealed no evidence of mutagenic or carcinogenic effects at 500?μg/well of AECNL. Conclusion: The median lethal dose (LD₅₀) of the AECNL is >5000?mg/kg and the no-observed-adverse-effect level is identified to be greater than 2000?mg/kg/day in 90-d study.     

Hetero-annulated coumarins as new AChE/BuChE inhibitors: synthesis and biological evaluation

A series of chromene-fused coumarins known as 10,11-dihydrochromeno[4,3-b]chromene-6,8(7H,9H)-diones 4a–o were synthesized through one-pot reaction of appropriate benzaldehydes, dimedone, and 4-hydroxycoumarin in the presence of nano-silica sulfuric acid under solvent-free condition in good yields. The in vitro anticholinesterase assay revealed that the 3-hydroxyphenyl analog 4e showed the highest inhibitory activity against both acetylcholinesterase and butyrylcholinesterase, possessing IC₅₀ values of 3.28 and 2.19?µM, respectively. The structure-activity relationships study demonstrated that the selectivity for acetylcholinesterase over butyrylcholinesterase could be modulated by introducing second hydroxyl or methoxy substituent on the para-position of the 3-hydroxyphenyl pendent group. The docking study of compound 4e with acetylcholinesterase confirmed π–π stacking interaction between the coumarin moiety and Trp279 as well as the formation of hydrogen bonding between hydroxyl group and Asn85.     

Are pancreatic IPMN volumes measured on MRI images more reproducible than diameters? An assessment in a large single-institution cohort

Objectives

To assess reproducibility of volume and diameter measurement of intraductal papillary mucinous neoplasms (IPMNs) on MRI images.

Methods

Three readers measured the diameters and volumes of 164 IPMNs on axial T2-weighted images and coronal thin-slice navigator heavily T2-weighted images using manual and semiautomatic techniques. Interobserver reproducibility and variability were assessed.

Results

Interobserver intraclass correlation coefficients (ICCs) for the largest diameter measured using manual and semiautomatic techniques were 0.979 and 0.909 in the axial plane, and 0.969 and 0.961 in the coronal plane, respectively. Interobserver ICCs for the volume measurements were 0.973 and 0.970 in axial and coronal planes, respectively. The highest intraobserver reproducibility was noted for coronal manual measurements (ICC 0.981) followed by axial manual measurements (ICC 0.969). For the diameter measurements, Bland-Altman analysis revealed the lowest interobserver variability for manual axial measurements with an average range of 95% limits of agreement (LOA) of 0.68 cm. Axial and coronal volume measurements showed similar 95% LOA ranges (8.9 cm³ and 9.4 cm³, respectively).

Conclusions

Volume and diameter measurements on axial and coronal images show good interobserver and intraobserver reproducibility. The single largest diameter measured manually on axial images showed the highest reproducibility and lowest variability. The 95% LOA may help define reproducible size changes in these lesions using measurements from different readers.

Key Points

? MRI measurements by different radiologists can be used for IPMN follow-up. ? Both diameter and volume measurements demonstrate excellent interobserver and intraobserver reproducibility. ? Manual axial measurements show the highest interobserver reproducibility in determining size. ? Axial and coronal volume measurements show similar limits of agreement. ? Manual axial measurements show the lowest variability in agreement range.

     

Kinetics of Primary and Memory Cytotoxic T Lymphocyte Responses to Herpes Simplex Virus 1 Infection: Granzyme B Mediated CTL Activity

Background: Herpes simplex virus type 1 is one of the most common viruses among human population. Studies demonstrate the essential role of cell mediated immunity, especially CD8+ T cells, in prevention and clearance of HSV1. Objective: It is of great importance to improve our knowledge about the kinetics of CTL responses to primary and secondary HSV-1 infection. Methods: Using a sensitive technique for detection and analysis of CD8+ T cells, granzyme B ELISA, the CTL activity in the spleens of Balb/c mice at various time points after intraperitoneal administration of HSV1 (strain KOS) in primary and secondary infections were determined. Results: During acute HSV-1 infection, virus specific cytotoxic T cells were detected at day 5 post virus inoculation and peaked at day 7. Six hours after secondary infection the activity of memory CD8+ T cells was detected and peaked at 12 hours post infection. Conclusion: The peak of CTL activity was found to be day 7 post infection in primary HSV-1 infections which decreased with time. In secondary infections, the activity of CTLs reached the highest level at 12 hours post infection.     

Prevalence of diabetes-associated autoantibodies among patients presenting with type 2 diabetes and related metabolic differences

BackgroundTo explores the prevalence of autoantibodies (zinc transporter 8 autoantibodies (ZnT8A), antibodies to insulin (IAAs), glutamic acid decarboxylase autoantibody (GAD65)), the relation of the type of positive autoantibody and the number of positive autoantibodies with the glycemic and lipid profile of the patients with LADA (Latent Autoimmune Diabetes in Adults) and compares it to the metabolic profile of patients presenting with type 2 diabetes (T2DM).Methods263 patients with T2DM were recruited for this cross-sectional study in Tehran, Iran. Data from patients included complete medical history, GAD65, ZnT8A, IAA and routine metabolic laboratory workup. Assay for autoantibodies were conducted using ELISA kits. The association between autoantibodies and glycemic and lipid profile of patients with diabetes was assessed using univariate and multivariate regression analysis.ResultsOur study revealed that among 263 patients with T2DM, 29 (11%) cases were positive for IAAs, 9 (3.4%) for ZnT8A, and 12 (4.6%) for GAD65. Six (2.3%) of the patients had triple positive antibodies. Patients with positive results were younger, had lower body mass index (BMI), c-peptide, triglyceride, low-density lipoprotein (LDL), and higher high-density lipoprotein (HDL), HbA1c and fasting blood glucose (FBG) levels. Triple antibody positivity was significantly associated with lower levels of C-Peptide, Triglycerides, FBG, and HbA1c compared to triple negative antibodies.ConclusionPatients with LADA positive for either of the autoantibodies (GAD65, ZnT8 and IAA) presented with worse glycemic control. Measurement of these autoantibodies can assist in discrimination of these patients and help with earlier control of glycemic profile.     

The impact of the right ventricular lead position on response to cardiac resynchronization therapy

Introduction: Left ventricular (LV) lead placement to the latest contracting area (concordant LV lead) is associated with better response to cardiac resynchronization therapy (CRT) compared to a discordant LV lead. However, the effect of the right ventricular (RV) lead site on CRT response is unclear. We investigated the relationship of the RV and LV lead positions on CRT response. Methods: In 131 CRT patients, the LV lead was positioned preferentially in a lateral or posterolateral vein and the RV lead to either the RV septum (RVS, n = 55) or RV apex (RVA, n = 76). The latest site of contraction was determined with two‐dimensional speckle tracking radial strain imaging and patients had a concordant LV lead position if pacing the latest segment, and discordant if not. Response was defined as ≥15% reduction in LV end systolic volume (LVESV) at 6‐month follow‐up. Results: There were no significant differences in mean reduction of LVESV at follow‐up (RVS vs RVA: ?23.3 ± 16% vs 22.1 ± 18%, P = 0.70) or rate of responders (58.2% vs 57.9%, P = 0.97) between the two groups. In patients with a concordant LV lead (n = 71), the response rate was significantly higher than those with a discordant lead (76.1% vs 36.7%, P < 0.001). There were no differences in outcomes in patients with a concordant or discordant LV lead according to the RV lead location. Conclusion: The extent of LV reverse remodeling following CRT is not related to the RV lead position, but is significantly higher in patients with a concordant LV lead. (PACE 2011; 34:467–474)     

Alterations in oxidative stress biomarkers associated with mild hyperlipidemia and smoking

Oxidative stress may increase the risk of atherosclerosis. The association of mild forms of hyperlipidemia, particularly primary hypertriglyceridemia, with oxidative stress has not been fully investigated. The aim of this study was to assess the alterations in oxidative stress biomarkers associated with three major types of mild untreated hyperlipidemia (hypercholesterolemia, hypertriglyceridemia and combined hyperlipidemia) in nonsmoker and smoker individuals. Five biomarkers were measured in 139 adult healthy men (83 nonsmokers and 56 smokers, ages 18-75), which included normolipidemic and hyperlipidemic subjects. Triglyceride levels were associated with a significant main effect on ferric reducing antioxidant power (FRAP) and 8-iso-prostaglandin F2α (iPF2α) levels in plasma (p<0.05 and p<0.005, respectively). Smokers with hypercholesterolemia, hypertriglyceridemia and combined hyperlipidemia had alterations in 1, 3 and 2 oxidative stress biomarkers compared to nonsmoker normolipidemics. Smokers (including normolipidemics and hyperlipidemics) had higher plasma FRAP (120.8 vs. 102.0 μM quercetin/l, p<0.05) and erythrocyte catalase activity (5125 vs. 4093 U/g Hb, p<0.01), while they had lower erythrocyte glutathione peroxidase activity (20.3 vs. 23.0 U/g Hb, p<0.05) compared to nonsmokers. These findings show that mild forms of hyperlipidemia, particularly in smokers, are associated with alterations in some oxidative stress biomarkers.