Protective effects of raw and cooked blackcurrant extract on DNA damage induced by hydrogen peroxide in human lymphoblastoid cells.

CONTEXT: Blackcurrant (Ribes nigrum L.) is a classical fruit that has long been used to make juice, liqueur and sometimes medicines in Europe. The beneficial effects of blackcurrant, which are inhibition of lipopolysaccharide-stimulated inflammatory, anticarcinogenesis and other health effects, have been reported. OBJECTIVE: Previously, we reported the antimutagenic activities of blackcurrant using a yeast gene mutation assay. In this study, we investigated whether this antimutagenicity of blackcurrant was confirmed in human cells. MATERIALS AND METHODS: We prepared four types of aqueous blackcurrant extracts (BCE) from mature and premature with or without heat treatment by microwave. Antioxidant activities of BCE were measured by the DPPH radical scavenger assay. In the DPPH radical scavenger assay, the maximum concentration of BCE was 1.6 mg/reaction. We investigated the antigenotoxic activities of BCE by the comet assay and micronucleus test using the human lymphoblastoid cell line TK6. In the comet assay, TK6 was treated with 300 µM H2O2 without or with BCE at concentrations of 0.5, 1.0, 2.0 and 3.0 mg/mL. In the micronucleus test, TK6 was treated with 1 mg/mL BCE without or with H2O2. RESULTS: All BCEs exhibited more than 90% of inhibition rates of DPPH radicals at the maximum concentration of BCE. DNA damage and micronuclei induced by H2O2 significantly decreased in the each BCE-treated condition. CONCLUSION: The results suggest that BCE treatment can reduce the genomic instability induced by H2O2 in human cells. We consider that these antigenotoxic effects are related to polyphenols, l-ascorbic acid and other antioxidant compounds.

Ligand-enabled cross-coupling of C(sp3)-H bonds with arylboron reagents via Pd(II)/Pd(0) catalysis.

There have been numerous developments in C-H activation reactions in the past decade. Attracted by the ability to functionalize molecules directly at ostensibly unreactive C-H bonds, chemists have discovered reaction conditions that enable reactions of C(sp(2))-H and C(sp(3))-H bonds with a variety of coupling partners. Despite these advances, the development of suitable ligands that enable catalytic C(sp(3))-H bond functionalization remains a significant challenge. Herein we report the discovery of a mono-N-protected amino acid ligand that enables Pd(II)-catalysed coupling of γ-C(sp(3))-H bonds in triflyl-protected amines with arylboron reagents. Remarkably, no background reaction was observed in the absence of ligand. A variety of amine substrates and arylboron reagents were cross-coupled using this method. Arylation of optically active substrates derived from amino acids also provides a potential route for preparing non-proteinogenic amino acids.

Pd(II)-catalyzed ortho-trifluoromethylation of benzylamines.

The Pd(II)-catalyzed ortho-C-H trifluoromethylation of benzylamines has been achieved utilizing an electrophilic CF3 reagent. Additives, such as H2O and Ag2O, were found to be crucial for obtaining good yields. This protocol will be useful in medicinal chemistry for the preparation of ortho-trifluoromethyl-substituted benzylamines.

Ligand-enabled methylene C(sp3)-H bond activation with a Pd(II) catalyst.

Pd(II) insertion into ß-methylene C(sp(3))-H bonds was enabled by a mutually repulsive and electron-rich quinoline ligand. Ligand tuning led to the development of a method that allows for installation of an aryl group on a range of acyclic and cyclic amides containing ß-methylene C(sp(3))-H bonds.

Ab initio theory for treating local electron excitations in molecules and its performance for computing optical properties.

In this article, as a first step to develop an efficient approximation for predicting the molecular electronic excited state properties at ab initio level, we propose local excitation approximation (LEA). In the LEA scheme, the only local electron excitations within selected substructure (Chromophore) are treated to calculate the targeted excited state wavefunctions, whereas the other electron excitations (local electron excitations in other substructure and charge-transfer excitations between different regions) are simply discarded. This concept is realized by using the localized molecular orbitals (LMO) localizing on the chromophore substructure. If the targeted transitions show the strong local character and the adequate substructure is selected as chromophore region, the LEA scheme can provide excited state properties without large loss of accuracy. The fatal slowdown of convergence speed of Davidson's iterative diagonalization due to the use of LMO can be avoided by additional transformation of LMOs. To assess the accuracy and efficiency of the LEA scheme, we performed test calculations using various compounds at configuration interaction single (CIS) and time-dependent Hartree-Fock (TDHF) level of theory.

Identification of four novel mutations in F5 associated with congenital factor V deficiency.

Coagulation factor V (FV) deficiency is a rare bleeding disorder characterized by low coagulant and antigen levels of FV with bleeding symptoms ranging from mild to severe. Only a limited number of mutations have been reported because of the large size of the factor V gene (F5) as well as the low prevalence. In this study, we have identified four novel mutations in F5 in five unrelated patients with congenital FV deficiency. All the patients, including two with undetectable FV activity, were asymptomatic and were found to have prolonged prothrombin time and activated partial thromboplastin time during preoperative screening or routine examinations. All four mutations found in this study are either missense or in-frame deletion. This is in contrast with previous reports of a high frequency of mutations introducing premature termination codons in inherited FV deficiency. Missense mutations of F5 might produce a mild phenotype and are not frequently diagnosed. Although FV deficiency is a very rare disorder with a predicted incidence of one in 1 million, this study suggests that the numbers of F5 mutations, especially missense mutations, are higher than estimated.

Assessment of time-dependent density functional schemes for computing the oscillator strengths of benzene, phenol, aniline, and fluorobenzene.

In present study the relevance of using the time-dependent density functional theory (DFT) within the adiabatic approximation for computing oscillator strengths (f) is assessed using different LDA, GGA, and hybrid exchange-correlation (XC) functionals. In particular, we focus on the lowest-energy valence excitations, dominating the UV/visible absorption spectra and originating from benzenelike HOMO(pi)-->LUMO(pi(*)) transitions, of several aromatic molecules: benzene, phenol, aniline, and fluorobenzene. The TDDFT values are compared to both experimental results obtained from gas phase measurements and to results determined using several ab initio schemes: random phase approximation (RPA), configuration interaction single (CIS), and a series of linear response coupled-cluster calculations, CCS, CC2, and CCSD. In particular, the effect of the amount of Hartree-Fock (HF) exchange in the functional is highlighted, whereas a basis set investigation demonstrates the need of including diffuse functions. So, the hybrid XC functionals--and particularly BHandHLYP--provide f values in good agreement with the highly correlated CCSD scheme while these can be strongly underestimated using pure DFT functionals. These results also display systematic behaviors: (i) larger f and squares of the transition dipole moments (mid R:mumid R:(2)) are associated with larger excitation energies (DeltaE); (ii) these relationships present generally a linear character with R>0.9 in least-squares fit procedures; (iii) larger amounts of HF exchange in the XC functional lead to larger f, R:mumid R:(2), as well as DeltaE values; (iv) these increases in f, mid R:mumid R:(2), and DeltaE are related to increased HOMO-LUMO character; and (v) these relationships are, however, not universal since the linear regression parameters (the slopes and the intercepts at the origin) depend on the system under investigation as well as on the nature of the excited state.

Design, synthesis and biological activity of selective and orally available TF/FVIIa complex inhibitors containing non-amidine P1 ligands.

We found the novel selective and orally available non-amidine TF/FVIIa complex inhibitor 21e, 4-({[(1S)-(aminocarbonyl)-3-methylbutyl]amino}carbonyl)-2'-({[4- (aminomethyl)phenyl]amino}carbonyl)-4'-(methylamino)biphenyl-2- carboxylic acid. The derivatives were synthesized by conversions of the isobutyl moiety and the introduction of alkylamino groups to 4'-position of the central phenyl ring of compounds 2a and 2b reported previously. Some compounds show increased in vitro anti-TF/FVIIa and PT prolongation activities. Among them, compound 21e reached and sustained micromolar plasma concentration levels of up to 2h after oral administration in mice. Moreover, compound 21e did not prolong the bleeding time even at the highest dose level in cynomolgus monkeys, while PT was prolonged 3.7-fold increases at this dose.

Potent and selective TF/FVIIa inhibitors containing a neutral P1 ligand.

Inhibition of tissue factor/factor VIIa complex (TF/FVIIa) is an attractive strategy for antithrombotic therapies. We began with an investigation of a non-amidine TF/FVIIa inhibitor based on a modification of amidine compound 1. Optimization of the substituents on the P1 phenyl portion of the compound 1 led to a neutral or less basic alternative for the 4-amidinophenyl moiety. By further optimization of the substituents on the central phenyl ring, a highly potent and selective TF/FVIIa inhibitor 17d was discovered.

Liver fat content measured by magnetic resonance spectroscopy at 3.0 tesla independently correlates with plasminogen activator inhibitor-1 and body mass index in type 2 diabetic subjects.

We measured liver fat content by 3-Tesla magnetic resonance spectroscopy (MRS) in 34 non- to mild obese Japanese subjects with type 2 diabetes, who were not complicated with any liver diseases including clinical fatty liver (liver/spleen ratio of computed tomography [CT] < 0.9) and were not being treated with oral hypoglycemic agents, insulin, or lipid-lowering agents, and analyzed the relationship between liver fat content and body composition and plasma metabolite. The liver fat content is significantly correlated with variables relating to obesity (body mass index [BMI], body weight, fat mass, waist to hip ratio, visceral fat area, subcutaneous fat area, and serum triglyceride), insulin resistance (fasting plasma insulin and homeostasis model assessment of insulin resistance [HOMA-IR]), adipocytokines (serum plasminogen activator inhibitor-1 [PAI-1] and leptin), and serum cholinesterase, but not CT liver/spleen ratio, which is correlated only with fasting plasma glucose, BMI, and HOMA-IR. Multiple regression analysis revealed that the liver fat content is independently associated with serum PAI-1 level (p < 0.001) and BMI (p < 0.05), but not visceral fat area. MRS is a more sensitive method for quantifying liver fat content than CT in type 2 diabetic subjects with non- to mild obesity and without clinical fatty liver.

Low incidence of vascular complications in patients with diabetes mellitus associated with liver cirrhosis as compared with type 2 diabetes mellitus.

We compared clinical features and vascular complications of patients with diabetes mellitus associated with liver cirrhosis versus patients with type 2 diabetes mellitus. Subjects were 19 patients (LC-DM group) in whom diabetes was diagnosed after development of liver cirrhosis. Control consisted of 38 patients with type 2 diabetes (T2DM group) matched for sex, age, duration of diabetes, body mass index, treatment, and degree of glycemic control, which was determined by glycoalbumin. The LC-DM group had significantly more smokers, higher serum insulin levels, more insulin resistance calculated by homeostasis model assessment, lower blood counts (white and red blood cells, hemoglobin, and platelets), and lower serum levels of total cholesterol, triglyceride, low density lipoprotein cholesterol and lipoprotein (Lp)(a) than the T2DM group. The incidence of diabetic retinopathy and cerebrovascular disease was significantly lower in the LC-DM group compared to the T2DM group. Logistic regression analysis indicated that Lp(a) and the diabetes duration were significant predictors for the retinopathy, while Lp(a) was a significant predictor for the cerebrovascular complication. In diabetes associated with liver cirrhosis, the incidence of diabetic retinopathy and cerebrovascular disease is lower than in type 2 diabetes mellitus in this study, probably because of lower levels of serum Lp(a).