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Abstract: The ridge gap waveguide is a new transmission line for millimeter-wave applications. Traditionally, rectangular waveguides are used for those applications due to their low loss. However their fabrication requires precision machining, very good electrical contact and alignment between two joining mechanical parts. Ridge gap waveguides can obtain similar performance without requiring conductive sidewalls and this provides more freedom during the fabrication and assembly process as the structure is no longer sensitive to small gaps between the side walls and the upper lid. The ridge gap waveguide has already been validated for 10-20GHz using conventional fabrication methods. The ridge gap waveguide prototypes presented in this paper are designed to work in the frequency region between 210 and 340GHz, and fabricated using MEMS technology. MEMS technology provides fabrication precision of the structures and thus opens the path for high-frequency components. [Copyright &y& Elsevier]

Despite convincing data demonstrating the benefits of aspirin (ASA), exercise, and dietary changes for both primary and secondary prevention of coronary heart disease, they remain underused. In this study, we assess whether higher coronary artery calcium (CAC) scores determined by electron beam computed tomography (EBCT) are associated with beneficial lifestyle behaviors in asymptomatic individuals. A total of 980 asymptomatic patients referred for EBCT risk assessment by their primary physician were sent a survey questioning them about health behaviors. We evaluated long-term ASA utilization, exercise, and dietary changes based on CAC using multivariable analysis. The study population consisted of 980 individuals (78% men, mean age 60 ± 8 years) who were followed for a mean of 3 ± 2 years after an initial EBCT scan. Overall, ASA initiation was lowest (29%) among those with CAC = 0, and gradually increased with higher CAC scores (1 to 99, 55%; 100 to 399, 61%; ≥400, 63%; p <0.001 for trend). Similarly, dietary changes and exercise were lowest (33% and 44%, respectively) among those with CAC = 0 and gradually increased with higher CAC scores (1 to 99, 40%; 100 to 399, 58%; ≥400, 56%; p <0.001 for trend for dietary changes; and 1 to 99, 62%; 100 to 399, 63%; ≥400, 67%; p <0.001 for trend for exercise). In multivariable analysis, greater baseline CAC was strongly associated with initiation of ASA therapy, dietary changes, and increased exercise. In conclusion, in addition to risk stratification of asymptomatic individuals, determination of CAC may also improve utilization of ASA therapy and behavioral modification. [Copyright &y& Elsevier]

Abstract: Both the anti- and pro-oxidant effects of tea catechins, have been implicated in the alterations of cellular functions which determine their chemoprotective and therapeutic potentials in toxicity and diseases. Here, we have studied the protective mechanism (s) of three main green tea catechins namely, epicatechin (EC), epicatechin gallate (ECG) and epigallocatechin gallate (EGCG) on free radical induced oxidative degradation of membrane lipids and proteins under in vitro conditions using isolated cell free fractions from rat liver. In addition, we have also studied the effects of the tea catechins on 2-deoxyribose degradation in the presence of Fenton and Haber–Weiss oxidants. Glutathione S-transferase and cytochrome P450 2E1 activities and lipid peroxidation were found to be markedly inhibited by tea catechins. These catechins also inhibited the reactive oxygen species formation and oxidative carbonylation of subcellular proteins induced by a physiological oxidant, 4-hydroxynonenal. EGCG and the other catechins showed a time and concentration-dependent effects on the degradation of 2-deoxyribose in the presence of Fenton oxidants. Our results indicate that tea catechins prevent molecular degradation in oxidative stress conditions by directly altering the subcellular ROS production, glutathione metabolism and cytochrome P450 2E1 activity. These results may have implications in determining the chemotherapeutic use of tea catechins in oxidative stress related diseases. [Copyright &y& Elsevier]

Background: There is an independent association between white blood cell (WBC) and coronary heart disease (CHD) risk. However, the relationship between WBC and Framingham Risk Score (FRS) remains unclear. Methods: This is a cross-sectional study on a consecutive sample of 520 white asymptomatic men (mean age 46 ± 7 years) without CHD. The study population was divided into WBC quartiles (×109 cells/L): 1st quartile: 3.1–5.3 (n = 139), 2nd quartile: 5.4–6.1 (n = 129), 3rd quartile: 6.2–7.1 (n = 131), 4th quartile: ≥7.2 (n = 121), and into tertiles according to the 10-year FRS: 1st tertile (low risk <5%, n = 180, 35%), 2nd tertile (intermediate risk 5–12%, n = 210, 40%), 3rd tertile (high risk: ≥13%, n = 130, 25%). Results: WBC correlated only weakly with FRS (r = 0.18, p = 0.001). Among individual components of FRS, WBC correlated minimally with smoking (r = 0.12, p = 0.003), systolic blood pressure (r = 0.07, p = 0.1), and high-density lipoprotein cholesterol (r = −0.06, p = 0.1). However, no correlation was observed with age (p = 0.3) and total cholesterol (p = 0.5). Nearly one third (31%) of men in the low-risk (FRS <5%) had WBC count in the 1st quartile compared to 20% of those classified as high risk (FRS ≥13%). The prevalence of WBC in the 4th quartile increased across FRS tertiles (18, 22, 32%) (p = 0.09). Conclusions: WBC correlates weakly with FRS or its individual components. Since WBC count is strongly related to CHD, WBC may reflect different components of cardiovascular risk, which might not be captured by traditional cardiovascular risk factors used in calculating FRS. Inflammatory biomarkers afford adjunctive value to FRS and may be used to improve CHD risk stratification. [Copyright &y& Elsevier]

Background: From a preventive aspect, it is especially important to investigate the lifestyle risk factors associated with cardiovascular disease (CVD). The purpose of this study was to determine the relationship of increasing metabolic syndrome (MS) components across increasing levels of estimated cardiorespiratory fitness (CRF) in asymptomatic young to middle-aged men. Methods: We studied 449 consecutive asymptomatic men (47 ± 7 years) who underwent a maximal treadmill exercise test according to the Bruce protocol. Cardiorespiratory fitness (CRF) was divided into tertiles based on metabolic equivalents (METs). The following MS components were studied: 1) waist circumference >102 cm; 2) serum triglycerides ≥150 mg/dL; 3) HDL cholesterol levels of <40 mg/dL; 4) fasting blood glucose (FBG) ≥110 mg/dL or 5) blood pressure ≥130/85 mmHg or treated hypertension. Multinomial logistic regression was used to investigate the relationship between clustering of MS components and CRF as determined by metabolic equivalents (METs). We used polytomous logistic regression to determine the likelihood of clustering of increasing components of metabolic syndrome with intermediate (2nd tertile) and low (1st tertile) levels of CRF as compared to those with highest levels of CRF (3rd tertile). Results: Overall in the study population, zero, 1, 2 and ≥3 (i.e., metabolic syndrome) risk factors for MS were observed in 29% (n = 129), 26% (n = 118), 22% (n = 98) and 23% (n = 104) men, respectively. The mean METS achieved in the study population was 10 ± 2 (range 4–20). Nearly half (49%) of individuals with the highest levels of CRF had no MS risk factors whereas only 18% of those with low CRF (METS <9) had no MS risk factors. On the other end of the spectrum, the prevalence of MS (≥3 MS risk factors) increased significantly across decreasing levels of CRF (6, 22, 33% p <0.0001 for trend). Multivariable polytomous logistic regression (adjusting for age, smoking, cholesterol-lowering therapy) demonstrated that individuals with low CRF (1st tertile of METS) compared to those with highest CRF had 3.1- (p = 0.001) and 11.8- (p <0.0001) fold higher risk of having 2 and ≥3 MS components, respectively. Similar results were observed when the analyses was repeated adjusting for Framingham risk score. Conclusions: Asymptomatic men with low levels of CRF have a greater likelihood for clustering of MS components and thus are at higher CVD risk. Further studies are needed to define the risk of cardiovascular disease in patients with intermediate levels of CRF and address which treatment strategies are most important given an individual''s risk profile. [Copyright &y& Elsevier]

Purpose: In patients with non-small cell lung cancer (NSCLC), concurrent chemoradiation therapy (CRT) exacerbates a cluster of difficult-to-manage symptoms, especially cancer-related fatigue. Minocycline is a readily available, low-cost antibiotic with antiinflammatory properties. We conducted a phase 2 randomized, double-blinded, placebo-controlled trial to investigate the effect of minocycline in reducing CRT-symptom burden in NSCLC.Methods and Materials: Patients with NSCLC scheduled to receive CRT provided consent and were randomized to receive either minocycline (100 mg twice daily) or a matching placebo during 6 to 7 weeks of CRT. Patient-reported fatigue and other symptoms were assessed on MD Anderson Symptom Inventory weekly from the start of CRT for 12 weeks. The primary outcome was 12-week (±2 days) area under the curve for symptom burden, which was compared between treatment groups.Results: Forty of 49 enrolled patients (80%) were evaluable (19 on minocycline and 21 on placebo). There were no grade 3 + adverse events related to the study medication. Fatigue was significantly reduced in the minocycline group compared with placebo group during the 12-week trial period (area under the curve = 31.2 ± 14.2 vs 45.0 ± 20.9, P = .011), with a large effect size (Cohen's d = 0.77). Pain (Cohen's d = 0.54) and shortness of breath (Cohen's d = 0.55) were also significantly reduced in the minocycline group (all P < .05).Conclusions: Minocycline during CRT for NSCLC was feasible, had a low toxicity profile, and yielded a clinically and statistically significant positive signal in reducing symptom burden related to NSCLC and CRT. This study is a proof of concept so a larger trial in CRT patients is warranted. [ABSTRACT FROM AUTHOR]

Context: Intensity-modulated radiation therapy (IMRT), three-dimensional conformal radiation therapy (3DCRT), and proton-beam therapy (PBT) are chemoradiotherapy modalities for treating locally advanced non-small-cell lung cancer. Although therapy is carefully planned to maximize treatment benefit while minimizing risk for adverse side effects, most patients develop radiation-induced symptom burden.Objectives: To demonstrate the MD Anderson Symptom Inventory's ability to detect fine differences in symptom development among these modalities.Methods: This was a longitudinal observational study. Patients with unresectable primary or recurrent non-small-cell lung cancer (n = 82) underwent 3DCRT, IMRT, or PBT. Patients rated MD Anderson Symptom Inventory symptoms weekly for up to 12 weeks. We used mixed-effect modeling to estimate development of symptoms and functional interference.Results: The PBT group received a significantly higher radiation target dose than did the IMRT and 3DCRT groups (P < 0.001). Fatigue was the most severe symptom over time for all groups. Controlling for patient and clinical factors (age, sex, race, cancer stage, performance status, body mass index, previous cancer therapy, total radiation dose), we found that pain, as a major esophagitis-related symptom, increased more during therapy (P = 0.019) and decreased more after (P = 0.013) therapy in the 3DCRT and IMRT groups than in the PBT group. Compared with the PBT group, the 3DCRT and IMRT groups reported greater decrease in systemic symptoms (fatigue, drowsiness, lack of appetite, disturbed sleep) after therapy (P = 0.016).Conclusion: Patients receiving PBT reported significantly less severe symptoms than did patients receiving IMRT or 3DCRT. These results should be confirmed in a randomized study with comparable tumor burden among therapies. [ABSTRACT FROM AUTHOR]

Context: Although it is well known that patients with advanced pancreatic cancer (PC) experience significant symptom burden, few strategies for effective symptom intervention are available for them.Objectives: To investigate the efficacy of minocycline, an anti-inflammatory agent, for symptom reduction in patients with advanced PC.Methods: We conducted Phase II, randomized, and placebo-controlled trial to obtain preliminary estimates of the effects on symptom reduction with 100 mg of minocycline or placebo given twice a day. Eligible patients had diagnosed advanced PC and were scheduled for standard chemotherapy. Patient-reported symptoms were measured weekly during the eight-week trial using the MD Anderson Symptom Inventory (MDASI) module in patients with gastrointestinal cancer. The primary outcome measure was the area under the curve values of the five most severe symptoms in the two arms.Results: Of the 44 patients recruited, 31 (71%) were evaluable for the primary efficacy analysis, with 18 received minocycline and 13 placebo. Fatigue, pain, disturbed sleep, lack of appetite, and drowsiness were the most severe symptoms reported by both groups. No significant differences in area under the curve values over time between the study arms were found for the composite MDASI score or single-item scores of the five most severe MDASI items. No treatment-related deaths were reported, and no Grade 3-4 toxicities were observed.Conclusion: Minocycline is safe for use in patients receiving treatment for PC. There is no observed symptom reduction with minocycline on the major symptom burden associated with advanced PC compared with placebo. Attrition because of rapid disease progression impacted the study significantly. [ABSTRACT FROM AUTHOR]

Abstract: The adsorption site of K on TiO2(110) 1×1 has been investigated at low coverage (&#60;0.15ML, where 1 monolayer corresponds to the number of surface unit cells). A combination of surface extended X-ray absorption fine structure (SEXAFS), scanning tunneling microscopy (STM), and non-contact atomic force microscopy (NC-AFM) was used for this purpose. SEXAFS identifies a threefold O hollow site in which K bonds to two bridging O atoms and one in-plane O atom at K–O bond distances of 2.49±0.12Å and 2.73±0.07Å. STM and NC-AFM images evidence a condensation of K atoms on either side of the bridging O row. [Copyright &y& Elsevier]