Directed diffraction without negative refraction

Using the FDTD method, we investigate the electromagnetic propagation in two-dimensional photonic crystals, formed by parallel air cylinders in a dielectric medium. The corresponding frequency band structure is computed using the standard plane-wave expansion method. It is shown that within partial bandgaps, waves tend to bend away from the forbidden directions. This phenomenon perhaps need not be explained in terms of negative refraction or `superlensing' behavior, contrast to what has been conjectured.Comment: 3 pages, 4 figure

Estimating systemic fibrosis by combining galectin-3 and ST2 provides powerful risk stratification value for patients after acute decompensated heart failure

Background: Two fibrosis biomarkers, galectin-3 (Gal-3) and suppression of tumorigenicity 2 (ST2), provide prognostic value additive to natriuretic peptides and traditional risk factors in patients with heart failure (HF). However, it is to be investigated whether their combined measurement before discharge provides incremental risk stratification for patients after acute HF. Methods: A total of 344 patients with acute HF were analyzed with Gal-3, and ST2 measured. Patients were prospectively followed for 3.7 ± 1.3 years for deaths, and composite events (death/HF-related re-hospitalizations). Results: The levels of Gal-3 and ST2 were only slightly related (r = 0.20, p < 0.001). The medians of Gal-3 and ST2 were 18 ng/mL and 32.4 ng/mL, respectively. These biomarkers compensated each other and characterized patients with different risk factors. According to the cutoff at median values, patients were separated into four subgroups based on high and low Gal-3 (HG and LG, respectively) and ST2 levels (HS and LS, respectively). Kaplan-Meier survival curves showed that HGHS powerfully identified patients at risk of mortality (Log rank = 21.27, p < 0.001). In multivariable analysis, combined log(Gal-3) and log(ST2) was an in­dependent predictor. For composite events, Kaplan-Meier survival curves showed a lower event- -free survival rate in the HGHS subgroup compared to others (Log rank = 34.62, p < 0.001; HGHS vs. HGLS, Log rank = 4.00, p = 0.045). In multivariable analysis, combined log(Gal-3) and log(ST2) was also an independent predictor. Conclusions: Combination of biomarkers involving heterogeneous fibrosis pathways may identify patients with high systemic fibrosis, providing powerful risk stratification value

Hepatocellular carcinoma detected by regular surveillance: Does timely confirmation of diagnosis matter?

AbstractBackgroundAlthough current guidelines recommended surveillance of hepatocellular carcinoma, prognosis in patients undergoing enhanced follow-up has yet to be evaluated.AimsExamine outcomes of hepatocellular carcinoma diagnosed during enhanced follow-up.MethodsDuring 2010–2012, 194 patients underwent ultrasonography surveillance were diagnosed with hepatocellular carcinoma and divided into: (A) immediate diagnosis (N=105, 54.1%) after positive ultrasonography, (B) enhanced follow-up: (N=38, 19.6%) for initial negative recall procedures, (C) late call back: (N=28, 14.4%) recall procedures were deferred after positive ultrasonography, and (D) beyond ultrasonography: (N=23, 11.9%) surveillance ultrasonography had been negative.ResultsMedian time from positive ultrasonography to confirmation of hepatocellular carcinoma were 9.5 months (2–67) in the Group B and 6.5 months (3–44) in the Group C. Stage distribution and 3-year survival rates were similar amongst all Groups. Surveillance intervals longer than 6 months were associated with the non-curative stage (3.7% vs. 12.5%, p=0.04). Nine (4.6%) patients underwent surveillance were diagnosed as Barcelona-Clinic Liver Cancer stage C.ConclusionEnhanced follow-up by current guidelines is appropriate that treatment can be deferred until a definite diagnosis. Despite optimal surveillance interval and recall policies, few non-curative stage diagnoses seemed inevitable under current standard of care

Effects of natto extract on endothelial injury in a rat model

Vascular endothelial damage has been found to be associated with thrombus formation, which is considered to be a risk factor for cardiovascular disease. A diet of natto leads to a low prevalence of cardiovascular disease. The aim of the present study was to investigate the effects of natto extract on vascular endothelia damage with exposure to laser irradiation. Endothelial damage both in vitro and in vivo was induced by irradiation of rose bengal using a DPSS green laser. Cell viability was determined by MTS assay, and the intimal thickening was verified by a histological approach. The antioxidant content of natto extract was determined for the free radical scavenging activity. Endothelial cells were injured in the presence of rose bengal irradiated in a dose-dependent manner. Natto extract exhibits high levels of antioxidant activity compared with purified natto kinase. Apoptosis of laser-injured endothelial cells was significantly reduced in the presence of natto extract. Both the natto extract and natto kinase suppressed intimal thickening in rats with endothelial injury. The present findings suggest that natto extract suppresses vessel thickening as a synergic effect attributed to its antioxidant and anti-apoptosis properties

Comparing the outcomes of two strategies for colorectal tumor detection: Policy-promoted screening program versus health promotion service

AbstractBackgroundThe Taiwanese government has proposed a population-based colorectal tumor detection program for the average-risk population. This study's objectives were to understand the outcomes of these screening policies and to evaluate the effectiveness of the program.MethodsWe compared two databases compiled in one medical center. The “policy-promoted cancer screening” (PPS) database was built on the basis of the policy of the Taiwan Bureau of National Health Insurance for cancer screening. The “health promotion service” (HPS) database was built to provide health check-ups for self-paid volunteers. Both the PPS and HPS databases employ the immunochemical fecal occult blood test (iFOBT) and colonoscopy for colorectal tumor screening using different strategies. A comparison of outcomes between the PPS and HPS included: (1) quality indicators—compliance rate, cecum reaching rate, and tumor detection rate; and (2) validity indicators—sensitivity, specificity, positive, and negative predictive values for detecting colorectal neoplasms.ResultsA total of 10,563 and 1481 individuals were enrolled in PPS and HPS, respectively. Among quality indicators, there was no statistically significant difference in the cecum reaching rate between PPS and HPS. The compliance rates were 56.1% for PPS and 91.8% for HPS (p < 0.001). The advanced adenoma detection rates of PPS and HPS were 1.0% and 3.6%, respectively (p < 0.01). The carcinoma detection rates were 0.3% and 0.4%, respectively (p = 0.59). For validity indicators, PPS provides only a positive predictive value for colorectal tumor detection. HPS provides additional validity indicators, including sensitivity, specificity, positive predictive value, and negative predictive value, for colorectal tumor screening.ConclusionIn comparison with the outcomes of the HPS database, the screening efficacy of the PPS database is even for detecting colorectal carcinoma but is limited in detecting advanced adenoma. HPS may provide comprehensive validity indicators and will be helpful in adjusting current policies for improving screening performance