An exact Green's function of the reversible diffusion-influenced reaction for an isolated pair in three dimensions with spherical symmetry for the "backreaction" boundary condition is presented. From this function, the survival probability and the rate coefficient are derived exactly in the time domain for the initially unbound pair. [S0031-9007(99)

LXR expression correlated with the degree of hepatic fat deposition, as well as with hepatic inflammation and fibrosis in NAFLD patients. Our research suggests that LXR is an attractive target for treatment and regulation of hepatic inflammation and fibrosis.

Effects of pair correlations between bound and unbound molecules on the relaxation kinetics of fast reversible reactions of the type A+B⇄C are investigated for one-, two-, and three-dimensional reaction systems in a unified manner. Starting from the many-body Smoluchowski equations for reactant molecule distribution functions, which are coupled in a hierarchical manner, we derive a set of reaction kinetic equations by using the dynamic superposition approximation. While most of previous theories are applicable only to the pseudo-first order case, the present theory is applicable to the second-order case as well. In the pseudo-first order case with B molecules present in excess of A molecules, we can consider two limiting situations where either A or B molecules are static. The present theory can deal with both limiting cases within a single theoretical framework. Previously, the two cases have been approached by using quite different theoretical formalisms. Simple analytic solutions are obtained that are applicable irrespective of the dimensionality of reaction system, and are shown to agree well with the full numerical solutions. The present theory shows that in the time dependence of the reactant concentration a transient rapid relaxation period precedes the well known long-time t−d/2 power-law decay phase, in agreement with the computer simulation results obtained by Edelstein and Agmon for the one-dimensional case.

The first asymmetric total synthesis of (-)-laurefucin (1), a unique C-15 acetogenin with a 2,8-dioxabicyclo[5.2.1]decane skeleton, has been accomplished in nine steps in 31% overall yield from known oxocene 10. Highlights of the highly stereoselective synthesis include a novel organoselenium-mediated biomimetic hydroxyetherification.

Dynamic correlation effect in reversible diffusion-influenced reactions: Brownian dynamics simulation in three dimensionsWe obtain the exact Green function for excited-state geminate reversible dissociation with two different lifetimes and quenching in one dimension, in the absence of a potential of interaction. We consider the ground-state and irreversible reactions as special limits, and investigate the long time asymptotic behavior in comparison with that observed in three dimensions.

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An intramolecular olefin keto-carbene cycloaddition reaction created the bicyclo[3.1.0]hexane template 10 that was necessary for the synthesis of carbocyclic amine 15. This amine is a direct precursor to a family of rigid nucleosides that are conformationally locked in the Southern hemisphere of the pseudorotational cycle. The synthesis of the conformationally locked adenosine analogue is reported herein as an illustrative example of the methodology. The racemic (South)-methanocarba adenosine analogue (+/-)-4 is the first example of a conformationally locked ribonucleoside version in the Southern hemisphere.

BackgroundDiabetes education and lifestyle modification are critical components in controlling blood glucose levels of people with type 2 diabetes. Until now, available data on the effectiveness of education with respect to the duration of diabetes are limited. We investigated whether adherence to lifestyle behavior modification prompted by diabetes education was influenced by the duration of diabetes.MethodsTwo hundred and twenty-five people with type 2 diabetes were recruited for an intensive, collaborative, group-based diabetes education program with annual reinforcement. We divided the patients into two groups based on the duration of their diabetes prior to the education program (≤1 year [≤1Y] vs. ≥3 years [≥3Y]). Dietary habits, physical activity, and the frequency of blood glucose self-monitoring were evaluated with a questionnaire prior to education and at the follow-up endpoint.ResultsThe mean follow-up period was 32.2 months. The mean hemoglobin A1c (A1C) value was significantly lower in the ≤1Y group. Self-care behaviors, measured by scores for dietary habits (P=0.004) and physical activity (P<0.001), were higher at the endpoint in the ≤1Y group than in the ≥3Y group. Logistic regression analysis revealed that a longer diabetes duration before education was significantly associated with mean A1C levels greater than or equal to 7.0% (53 mmol/mol).ConclusionDiabetes duration influenced the effectiveness of diabetes education on lifestyle behavior modification and glycemic control. More-intense, regular, and sustained reinforcement with encouragement may be required for individuals with longstanding type 2 diabetes.