Carotid Plaque Composition Assessed by CT Predicts Subsequent Cardiovascular Events among Subjects with Carotid Stenosis

BACKGROUND AND PURPOSE

Currently, the characteristics of carotid plaques are considered important factors for identifying subjects at high risk of stroke. This study aimed to test the hypothesis that carotid plaque composition assessed by CTA is associated with an increased risk of future major adverse cardiovascular events among asymptomatic subjects with moderate-to-severe carotid artery stenosis.

MATERIALS AND METHODS

This single-center, retrospective cohort study included 194 carotid plaques from 176 asymptomatic subjects with moderate-to-severe carotid artery stenosis. The association of CTA-determined plaque composition with the risk of subsequent adverse cardiovascular events was analyzed.

RESULTS

During a median follow-up of 41 months, the adverse cardiovascular event incidence among 194 carotid plaques was 19.6%. There were significant differences in plaque Hounsfield units (P < .001) and spotty calcium presence (P < .001) between carotid plaques from subjects with and without subsequent adverse cardiovascular events. Multivariable analysis revealed carotid plaque Hounsfield unit density (P < .001) and spotty calcium (P < .001) as independent predictors of subsequent adverse cardiovascular events. In association with moderate carotid artery stenosis, the plaque Hounsfield unit values were significantly lower among carotid plaques from subjects who experienced subsequent adverse cardiovascular events (P = .002), strokes (P = .01), and cardiovascular deaths (P = .04); the presence of spotty calcium was significantly associated with the occurrence of adverse cardiovascular events (P = .001), acute coronary syndrome (P = .01), and cardiovascular death (P = .04).

CONCLUSIONS

Carotid plaque Hounsfield unit density and spotty calcium were independent predictors of a greater risk of adverse cardiovascular event occurrence.

1140 Sleep Disturbances, Lifestyle, And Self-Management In Adults With Subarachnoid Hemorrhage

Introduction

Subarachnoid hemorrhage (SAH) survivors often suffer sleep disturbances. Self-management strategies focusing on lifestyle changes and health-promoting behaviors may improve sleep in SAH survivors. Few studies have examined sleep in SAH survivors, and little is known about sleep management practices used to improve their sleep. The purposes of this study were to: 1) describe the prevalence of sleep disturbances using subjective and objective sleep measures, and 2) explore interest in and engagement with self-management practices to promote sleep health in SAH survivors.

Methods

We conducted a cross-sectional study with a convenience sample of 30 SAH survivors recruited from a university hospital. We assessed sleep quality using the Pittsburgh Sleep Quality Index (PSQI), daytime sleepiness using the Epworth Sleepiness Scale (ESS), and objective sleep using wrist actigraphy. We conducted content analysis of semi-structured interviews, with two authors each coding sleep disturbances and self-management practices addressing sleep.

Results

Seventy-three percent of SAH survivors reported poor sleep quality (PSQI &gt; 5) and 27% had daytime sleepiness (ESS &gt; 10). Actigraphy analysis indicated that 41% of SAH survivors slept less than 7 hours or more than 9 hours. Interview content analyses suggested 3 themes and 15 sub-categories: 1) Sleep disturbances (difficulties in falling asleep, wake after sleep onset, daytime sleepiness, too much or insufficient sleep, and poor sleep quality), 2) Sleep management practices (exercise, regular sleep schedule, relaxation, keeping busy and staying active, changing beverage intake, taking supplements, taking medication, recharging energy, and barriers to sleep management), and 3) Healthcare providers (discussing sleep problems with health care providers).

Conclusion

Sleep disturbances are highly prevalent and an urgent need exists to focus on improving sleep in SAH survivors. Developing tailored interventions that incorporate self-management and lifestyle change would be a critical next step to improve sleep and promote health in this at-risk population.

Support

This research was supported by grants from the National Institutes of Health/National Institute of Nursing Research (K23 NR017404), University of Washington Institute of Translational Health Science Translational Research Scholars Program (UL1 TR000423), and University of Washington School of Nursing Research and Intramural Funding Program.

Activation of NF-κB and AP-1 Mediates Hyperproliferation by Inducing β-Catenin and c-Myc in Helicobacter pylori-Infected Gastric Epithelial Cells

PURPOSE

In the gastric mucosa of Helicobacter pylori (H. pylori)-infected patients with gastritis or adenocarcinoma, proliferation of gastric epithelial cells is increased. Hyperproliferation is related to induction of oncogenes, such as β-catenin and c-myc. Even though transcription factors NF-κB and AP-1 are activated in H. pylori-infected cells, whether NF-κB or AP-1 regulates the expression of β-catenein or c-myc in H. pylori-infected cells has not been clarified. The present study was undertaken to investigate whether H. pylori-induced activation of NF-κB and AP-1 mediates the expression of oncogenes and hyperproliferation of gastric epithelial cells.

MATERIALS AND METHODS

Gastric epithelial AGS cells were transiently transfected with mutant genes for IκBα (MAD3) and c-Jun (TAM67) or treated with a specific NF-κB inhibitor caffeic acid phenethyl ester (CAPE) or a selective AP-1 inhibitor SR-11302 to suppress activation of NF-κB or AP-1, respecively. As reference cells, the control vector pcDNA was transfected to the cells. Wild-type cells or transfected cells were cultured with or without H. pylori.

RESULTS

H. pylori induced activation of NF-κB and AP-1, cell proliferation, and expression of oncogenes (β-catenein, c-myc) in AGS cells, which was inhibited by transfection of MAD3 and TAM67. Wild-type cells and the cells transfected with pcDNA showed similar activities of NF-κB and AP-1, proliferation, and oncogene expression regardless of treatment with H. pylori. Both CAPE and SR-11302 inhibited cell proliferation and expression of oncogenes in H. pylori-infected cells.

CONCLUSION

H. pylori-induced activation of NF-κB and AP-1 regulates transcription of oncogenes and mediates hyperproliferation in gastric epithelial cells.

One-pot reductive mono-N-alkylation of aniline and nitroarene derivatives using aldehydes

One-pot reductive mono-N-alkylation of aniline and nitroarene derivatives using various aldehydes by Pd/C catalyst in aqueous 2-propanol solvent with ammonium formate as in situ hydrogen donor is illustrated. The reaction proceeded smoothly and selectively with excellent yield at room temperature. Our protocol presents a facile, economical, and environmentally benign alternative for reductive amination.

The abstraction of intervening concepts from experience with multiple input-multiple output causal environments

The purpose of this article is threefold: (a) introduce a new paradigm for investigating how intervening concepts are learned, (b) report four new experiments that provide converging evidence for the acquisition of intervening concepts, and (c) propose a simple associative learning mechanism to account for the results. The new paradigm utilizes a stimulus-response-feedback task in which subjects learn trial by trial how a multivariate set of inputs maps into a multivariate set of outputs. The first two experiments use evidence based on a principal component analysis to replicate the finding that intervening-concept learning occurs spontaneously, but only in environments that contain an intervening factor. The next experiment provides a second converging line of evidence for this conclusion by showing that subjects can use an intervening concept to make accurate inferences to a new fourth output during a transfer test. The last experiment provides a third line of evidence by showing that subjects can use an intervening concept to make accurate inferences from a new fourth input. The results are explained by a hidden-unit connectionist learning mechanism that includes both accuracy and parsimony as learning objectives.

Sulfhydryl groups are essential for organic cation exchange in rabbit renal basolateral membrane vesicles

The effect of N-ethylmaleimide (NEM), an irreversible sulfhydryl modifying reagent, on the transport of organic cations in the renal basolateral membrane was examined. The studies were conducted examining the exchange of [3H]tetraethylammonium (TEA) for unlabeled TEA in basolateral membrane vesicles isolated from the outer cortex of rabbit kidneys. NEM inactivated TEA transport in a dose-dependent fashion with an IC50 value of 260 microM. The rate of TEA transport inactivation followed apparent pseudo-first-order reaction kinetics. A replot of the data gave a linear relationship between the apparent rate constants and the NEM concentration with a slope of 4.0. The data imply that inactivation involves the binding of at least four molecules of NEM per active transport unit. This is most consistent with the presence of four sulfhydryl groups at this site. The substrate TEA displayed a dose-dependent enhancement of NEM inactivation, with 50% enhancement occurring at 365 microM TEA. Another organic cation, N1-methylnicotinamide, known to share a common transport mechanism with the TEA/TEA exchanger is also capable of increasing the reactivity of sulfhydryl groups to NEM. These results demonstrate that there are essential sulfhydryl groups for organic cation transport in the basolateral membrane. In addition, the capability of organic cations to alter the susceptibility to sulfhydryl modification suggests that these groups may have a dynamic role in the transport process.