Comparisons of Left Atrial Functional Parameters with Left Ventricular Diastolic Dysfunction in a Large Taiwanese Population with Normal Left Ventricular Ejection Fraction According to Age.

BACKGROUND: Recent studies have shown that left atrial (LA) volume is a sensitive morphophysiological indicator of the severity of LV dysfunction and may also be a useful index of cardiovascular risk. In this study, we performed comparisons among left atrial (LA) functional parameters for predicting age-related diastolic dysfunction. METHODS: Echocardiography was performed in 2248 healthy participants with a low possibility of heart disease according to the decennium of age, and reference values were established. Progressive diastolic dysfunction paralleled increasing age and could be well identified by traditional and advanced echocardiographic parameters, including mitral inflow pattern, tissue Doppler parameters, and LA volume. RESULTS: Regarding LA functional parameters analyzed based on the decennium of age, left atrial ejection fraction (LAEF) and emptying fraction could not represent aging diastolic dysfunction well, but LA expansion index ((Volmax - Volmin) × 100% / Volmin) could. Volmax indicated maximal LA volume and Volmin indicated minimal LA volume. In assessments of diastolic dysfunction with receiver operating characteristic curve analysis, the best cut-off value of LA expansion index was < 100%, with an area under the curve (AUC) of 0.86, sensitivity of 80%, and specificity of 74%. LAEF < 30% (AUC 0.76, sensitivity 67%, specificity 70%) and LA emptying fraction < 50% (AUC 0.80, sensitivity 72%, specificity 71%) were also useful but performed less well. CONCLUSIONS: Compared with other LA functional parameters, LA expansion index can well represent age-related diastolic dysfunction.

Corrigendum: Tetrac and NDAT Induce Anti-proliferation via Integrin αvß3 in Colorectal Cancers With Different K-RAS Status.

[This corrects the article DOI: 10.3389/fendo.2019.00130.].

Tetrac and NDAT Induce Anti-proliferation via Integrin αvß3 in Colorectal Cancers With Different K-RAS Status.

Colorectal cancer is a serious medical problem in Taiwan. New, effective therapeutic approaches are needed. The selection of promising anticancer drugs and the transition from pre-clinical investigations to clinical trials are often challenging. The deaminated thyroid hormone analog (tetraiodothyroacetic acid, tetrac) and its nanoparticulate analog (NDAT) have been shown to have anti-proliferative activity in vitro and in xenograft model of different neoplasms, including colorectal cancers. However, mechanisms involved in tetrac- and NDAT-induced anti-proliferation in colorectal cancers are incompletely understood. We have investigated possible mechanisms of tetrac and NDAT action in colorectal cancer cells, using a perfusion bellows cell culture system that allows efficient, large-scale screening for mechanisms of drug actions on tumor cells. Although integrin αvß3 in K-RAS wild type colorectal cancer HT-29 cells was far less than that in K-RAS mutant HCT116 cells, HT-29 was more sensitive to both tetrac and NDAT. Results also indicate that both tetrac and NDAT bind to tumor cell surface integrin αvß3, and the agents may have different mechanisms of anti-proliferation in colorectal cancer cells. K-RAS status appears to play an important role in drug resistance that may be encountered in treatment with this drug combination.