Interaction of smoking, hyperhomocysteinemia, and metabolic syndrome with carotid atherosclerosis: A cross-sectional study in 972 non-diabetic patients.

Objectives: Little is known about the interactions between hyperhomocysteinemia and metabolic syndrome (MetS) in individuals at risk for atherosclerosis. The aim of this study was to assess the burden of atherosclerosis in patients with MetS and hyperhomocysteinemia.

Methods: We assessed the interaction of MetS with other risk factors including hyperhomocysteinemia in 972 patients with a history of stroke, transient ischemic attack, or carotid stenosis.

Fractal dimension based carotid plaque characterization from three-dimensional ultrasound images.

Irregularity of the plaque surface associated with previous plaque rupture plays an important role in the risk estimation of stroke caused by carotid atherosclerotic lesions. Thus, the aim of this study is to develop and validate novel vulnerability biomarkers from three-dimensional ultrasound (3DUS) images by analyzing the surface morphological characteristics of carotid plaque using fractal geometry features. In the experiments, a total of 38 3DUS plaque images were obtained from two groups of patients treated with 80 mg of atorvastatin or placebo daily for 3 months respectively.

Effect of Extended Benzannelation Orientation on Bergman and Related Cyclizations of Isomeric Quinoxalenediynes.

A combined computational and experimental study was conducted to examine the effect of extended benzannelation orientation on C-C and C-C cyclization of acyclic quinoxalenediynes. Calculations (mPW1PW91/cc-pVTZ//mPW1PW91/6-31G(d,p)) on terminal and phenylethynyl-substituted 5,6-diethynylquinoxaline and 6,7-diethynylquinoxaline showed C-C Bergman cyclization as the favored thermodynamic reaction pathway, with larger C-C preference for the angular quinoxalenediynes due to gain of a new aromatic sextet. Kinetic studies, as a function of 1,4-cyclohexadiene concentration, revealed retro-Bergman ring opening predominates over hydrogen atom abstraction (k > k) for 6,7-diethynylquinoxaline while 5,6-diethynylquinoxaline undergoes irreversible Bergman cyclization indicative of a large retro-Bergman ring opening barrier (k > k).

Adding carotid total plaque area to the Framingham risk score improves cardiovascular risk classification.

Introduction: Cardiovascular events (CE) due to atherosclerosis are preventable. Identification of high-risk patients helps to focus resources on those most likely to benefit from expensive therapy. Atherosclerosis is not considered for patient risk categorization, even though a fraction of CE are predicted by Framingham risk factors.

B vitamin therapy for homocysteine: renal function and vitamin B12 determine cardiovascular outcomes.

Therapy to lower homocysteine with B vitamins does reduce the risk of stroke, if not myocardial infarction. The apparent lack of efficacy of vitamin therapy in most of the large clinical trials was probably determined by the failure to take account of the metabolic deficiency of vitamin B12, which is very common and often missed, and by the failure to take account of impaired renal function. Metabolic B12 deficiency is present in 20% of people over 65 years of age, and in 30% of vascular patients above 70 years, so higher doses of B12 are needed in elderly patients.

Provider and state perspectives on implementing cultural-based models of care for american Indian and alaska native patients with substance use disorders.

American Indians/Alaska Natives (AI/ANs) suffer disproportionate rates of substance use disorders compared to Americans overall. Providers serving AI/AN communities are drawing from a diverse toolkit of treatment strategies that incorporate Native worldviews and community-shared values in order to improve outcomes. This paper describes findings from interviews with 22 program directors and 18 representatives from Single State Authorities on substance abuse.

Syntheses, thermal reactivities, and computational studies of aryl-fused quinoxalenediynes: effect of extended benzannelation on Bergman cyclization energetics.

A series of [b]-fused 6,7-diethynylquinoxaline derivatives have been synthesized through an imine condensation strategy to examine the effect of extended benzannelation on the thermal reactivity of enediynes. Absorption and emission spectra of the highly conjugated quinoxalenediynes were red-shifted approximately 100-200 nm relative to those of 1,2-diethynylbenzene. Strong exotherms indicative of enediyne cyclization were observed by differential scanning calorimetry, while solution cyclizations in the presence of 1,4-cyclohexadiene confirmed C(1)-C(6) Bergman cyclization.

Syntheses and reactivity of naphthalenyl-substituted arenediynes.

A series of naphthalenyl-substituted arenediynes were prepared to examine photochemical reactivity. For naphthalen-1-ylethynyl arenediyne, 350 nm photolysis resulted in a tandem [2 + 2] photocycloaddition to afford cyclobutene adducts. For naphthalen-2-ylethynyl derivatives, electron-donating methoxy substituents were found to facilitate C(1)-C(6) Bergman cyclization at 300 nm.

Improvement of cardiovascular risk prediction: time to review current knowledge, debates, and fundamentals on how to assess test characteristics.

Cardiovascular risk assessment might be improved with the addition of emerging, new tests derived from atherosclerosis imaging, laboratory tests or functional tests. This article reviews relative risk, odds ratios, receiver-operating curves, posttest risk calculations based on likelihood ratios, the net reclassification improvement and integrated discrimination. This serves to determine whether a new test has an added clinical value on top of conventional risk testing and how this can be verified statistically.

Synthesis of diazacalix[8]arene and triazacalix[12]arene methyl ethers via intramolecular aryl amination.

Azacalixarenes derived from p-tert-butylphenol are generated by an intramolecular aryl amination strategy as the ring-closing step. The reaction produces the first examples of larger p-tert-butylcalixarenes with regioselective substitution of bridging methylenes with nitrogen atoms.

Synthesis and Bergman cyclization of a beta-extended porphyrenediyne.

Condensation of a porphyrin-2,3-dione with a 1,2-diaminoarenediyne affords a [small beta]-extended porphyrinic-enediyne: upon thermal Bergman cyclization the quinoxaline spacer positioned between the macrocycle and the enediyne prevents tandem radical cyclization to a picenoporphyrin.

Regioselective oxidations of benzocarbaporphyrins with ferric chloride: a facile synthesis of bridged [18]annulene ketals with strong absorptions in the far red and an unexpected halogenation reaction at the interior carbon atom.

Benzocarbaporphyrins 4 were found to undergo regioselective oxidations with ferric chloride in methanol, ethanol, isopropyl alcohol, or ethylene glycol to give bridged benzo[18]annulene ketal derivatives 5 in excellent yields. These polar derivatives were generally isolated in a monoprotonated form and the corresponding free bases appeared to be relatively unstable. Addition of TFA resulted in the formation of spectroscopically distinct dications.

Conjugated macrocycles related to the porphyrins. 21. Synthesis, spectroscopy, electrochemistry, and structural characterization of carbaporphyrins.

The "3 + 1" variant of the MacDonald condensation has been shown to be an excellent methodology for synthesizing carbaporphyrins. In particular, 1,3-indenedicarbaldehyde condenses with tripyrranes in the presence of TFA to give, following oxidation with DDQ, a series of benzocarbaporphyrins in excellent yields. Triformylcyclopentadienes also afford carbaporphyrin products, albeit in low yields ranging from 5 to 8%.

Actuating Cycloaromatization of a Bicyclo[7.3.1]enediyne by Annelation: An Example of Inverse Dependence on Bridge Atom Hybridization.

Although the acetylenic carbon atoms in 2 are closer together than those in 1, only the latter undergoes Bergman cyclization. In contrast, in analogous enediynes without an annelated cyclohexane ring a change in the hybridization of the bridging carbon atom from sp to sp leads to a dramatic increase in the cyclization rate.

Stereogenic Propargylic Centers via Base-Mediated Terminal Allene Isomerization.

A study of alkali metal amide-mediated isomerizations of terminal allenes is described. The isomerizations of substituted ethenylidenecyclohexanes to form diastereomeric mixtures of terminal alkynes have been conducted to determine factors which may influence the stereochemistry at the newly formed propargylic centers. An initial base screen revealed that potassium N-methylbutylamide (KMBA) exhibits the highest level of equatorial to axial alkyne diastereoselectivity.