64Cu-ATSM internal radiotherapy to treat tumors with bevacizumab-induced vascular decrease and hypoxia in human colon carcinoma xenografts

Bevacizumab, an anti-vascular endothelial growth factor (VEGF) antibody, is an antiangiogenic agent clinically used for various cancers. However, repeated use of this agent leads to tumor-decreased vascularity and hypoxia with activation of an HIF-1 signaling pathway, which results in drug delivery deficiency and induction of malignant behaviors in tumors. Here, we developed a novel strategy to treat tumors with bevacizumab-induced vascular decrease and hypoxia using ⁶⁴Cu-diacetyl-bis (N⁴-methylthiosemicarbazone) (⁶⁴Cu-ATSM), a potential theranostic agent, which possesses high tissue permeability and can target over-reduced conditions under hypoxia in tumors, with a human colon carcinoma HT-29 tumor-bearing mouse model. The long-term treatment with bevacizumab caused decreased blood vessel density and activation of an HIF-1 signaling pathway; increased uptake of ⁶⁴Cu-ATSM was also observed despite limited blood vessel density in HT-29 tumors. In vivo high-resolution SPECT/PET/CT imaging confirmed reduced vascularity and increased proportion of ⁶⁴Cu-ATSM uptake areas within the bevacizumab-treated tumors. ⁶⁴Cu-ATSM therapy was effective to inhibit tumor growth and prolong survival of the bevacizumab-treated tumor-bearing mice without major adverse effects. In conclusion, ⁶⁴Cu-ATSM therapy effectively enhanced anti-tumor effects in tumors with bevacizumab-induced vascular decrease and hypoxia. ⁶⁴Cu-ATSM therapy could represent a novel approach as an add-on to antiangiogenic therapy.

Abstract P346: Diurnal Variation of Serum Uric Acid Levels and Corresponding Variations of Oxidative Stress Makers in Patients With Hypertension and Stable Coronary Artery Disease

Background: Hyperuricemia has been known as a risk factor of hypertension, stroke and coronary artery disease (CAD). Uric acid (UA) itself has antioxidative activity, but it is also reported that UA can also stimulate oxidative stress. In healthy subjects, it has been shown that UA has diurnal variation; elevate in the early morning. However, it is unclear whether such diurnal variation is observed and whether corresponding diurnal variation of oxidative stress can also be observed even in patients with CAD. Therefore, we investigated presence of diurnal variation of serum levels of UA, oxidative stress makers in patients with hypertension and CAD.

Method: We measured serum levels of UA, NOx, and urinary levels of 8-OHdG, serum at 6 p.m., 6 a.m., 12 p.m. in 26 men with CAD. We excluded patients who was taking drugs which can affect UA levels.

Result: Overall 20 patients were enrolled. Serum UA levels were 5.67±0.99 mg/dl at 6 p.m., 5.86±0.99 mg/dl at 6 a.m., and 5.73±0.99 mg/dl at 12 p.m., indicating obvious diurnal variation (P=0.0004). Serum UA levels increased significantly from 6 p.m. to 6 a.m. (P=0.002) and decreased significantly from 6 a.m. to 12 p.m. (P=0.002). Urinary level of 8-OHdG were 13.96±4.95 ng/mlCr at 6 p.m., 19.47±9.20 ng/mlCr at 6 a.m., and 16.19±5.52 ng/mlCr at 12 p.m., indicting corresponding diurnal variation to the serum UA level (P=0.013). Similarly, urinary levels of 8-OHdG increased significantly from 6 p.m. to 6 a.m. (P=0.008) and tend to decrease from 6 a.m. to 12 p.m. (P=0.57). Serum NOx levels were 13.19±6.60μM at 6 p.m., 12.11±6.02μM at 6 a.m. and 15.08±6.61μM at 12 p.m. and showed reciprocal diurnal variation to the serum UA and urinary 8-OHdG levels (p=0.0028).

Discussion: Serum UA levels showed diurnal variation even in patients with hypertension and CAD. Considering the fact that oxidative stress makers showed corresponding diurnal variations, diurnal variation of serum UA level may play a role in the pathogenesis of CAD.

A pulsed-air model of blue whale B call vocalizations

Blue whale sound production has been thought to occur by Helmholtz resonance via air flowing from the lungs into the upper respiratory spaces. This implies that the frequency of blue whale vocalizations might be directly proportional to the size of their sound-producing organs. Here we present a sound production mechanism where the fundamental and overtone frequencies of blue whale B calls can be well modeled using a series of short-duration (<1 s) wavelets. We propose that the likely source of these wavelets are pneumatic pulses caused by opening and closing of respiratory valves during air recirculation between the lungs and laryngeal sac. This vocal production model is similar to those proposed for humpback whales, where valve open/closure and vocal fold oscillation is passively driven by airflow between the lungs and upper respiratory spaces, and implies call frequencies could be actively changed by the animal to center fundamental tones at different frequency bands during the call series.

Change in type of sleep-disordered breathing from predominant central to obstructive sleep apnea following coronary artery bypass grafting

We report the case of a 67-year-old overweight man with reduced left ventricular ejection fraction (LVEF) due to myocardial infarction. He had an implantable cardioverter defibrillator (ICD) for frequent episodes of ventricular tachyarrhythmia and was initiated into adaptive-servo ventilation therapy for severe central sleep apnea (CSA), which was not suppressed by continuous positive airway pressure (CPAP). Since he still had several episodes of appropriate ICD therapies, coronary angiogram was performed, and severe three-vessel disease was found. He then underwent coronary artery bypass grafting (CABG). After CABG, his LVEF did not improve (from 29 to 25%); however, the B-type natriuretic peptide level decreased (from 560 to 330 pg/mL). Although the apnea-hypopnea index did not change (49.4 before and 55.1/h after CABG), his CSA converted to predominant obstructive sleep apnea accompanied by a shortening of the lung-to-finger circulation time (from 43 to 29 s) 2 weeks after CABG, which was completely suppressed by CPAP. <Learning objective: Central sleep apnea (CSA) can be alleviated by treatments for heart failure. However, limited data are available regarding resolution of CSA after coronary revascularization. We describe a case whose predominant CSA converted to obstructive sleep apnea after surgical coronary revascularization without any improvements in systolic function. Coronary revascularization can alleviate CSA possibly through altering congestive status and may unmask obstructive phenotype in patients with severe coronary artery disease.>.

IL4Rα and ADAM33 as genetic markers in asthma exacerbations and type-2 inflammatory endotype

BACKGROUND

Genetic markers of susceptibility to asthma exacerbations in adults remain unclear.

OBJECTIVE

To identify genetic markers of asthma exacerbations, particularly in patients with type-2 inflammatory endotype.

METHODS

In this observational study of patients enrolled in the Kinki Hokuriku Airway disease Conference multicenter study, frequency of exacerbations requiring systemic corticosteroids during 2 years after enrolment and associated risk factors was determined. For genetic marker analysis, interleukin-4 receptor α (IL4RA) rs8832 and a disintegrin and metalloprotease 33 (ADAM33) S_2 (rs528557), T_1 (rs2280091), T_2 (rs2280090), and V_4 (rs2787094) variants were included. Elevated serum periostin levels at enrolment (≥95 ng/mL, defined as type-2 inflammatory endotype) were considered in the analysis.

RESULTS

Among 217 patients who were successfully followed up for 2 years after enrolment, 60 patients showed at least one asthma exacerbation during the 2 years. Airflow limitation (%FEV₁ <80%) and recent exacerbations but not genetic variants were identified as risk markers of exacerbations. A total of 27 patients showed type-2 inflammatory endotype (serum periostin ≥95 ng/mL at enrolment) and subsequent exacerbations; risk factors in these patients were airflow limitation (odds ratio, 6.51; 95% confidence interval (CI): 2.37-18.6; P=.0003), GG genotype of IL4RA rs8832 (odds ratio, 4.01; 95% CI: 1.47-11.0; P=.007), and A allele of ADAM33 T_2 (odds ratio, 2.81; 95% CI: 1.05-7.67; P=.04) by multivariate analysis. In addition, GG genotype of IL4RA rs8832 was associated with type-2 endotype, whereas A allele of ADAM33 T_2 was associated with mixed type of eosinophilic/type-2 and neutrophilic inflammations.

CONCLUSIONS AND CLINICAL RELEVANCE

IL4RA and ADAM33 variants may be risk markers of asthma exacerbations in type-2 inflammatory endotype. Precise endotyping may facilitate the identification of genetic risk markers of asthma exacerbations.

Phenytoin-induced gingival overgrowth caused by death receptor pathway malfunction

OBJECTIVE

In this study, we investigated the role of phenytoin (PHT) in death receptor-induced apoptosis of gingival fibroblasts to clarify the mechanism of PHT-induced gingival overgrowth.

METHODS

Human gingival fibroblasts were cultured to semiconfluence and treated with PHT (0.025, 0.1, 0.25, and 1.0 μM) for 48 h, and then, the apoptotic cell numbers were relatively determined by absorptiometry. After 24 h of 0.25 μM PHT treatment, caspase activity was measured by absorptiometry, apoptotic and cell cycle phase distribution was analyzed by flow cytometry, expression levels of apoptotic genes were quantified by real-time qPCR, and expression of apoptotic proteins was detected by Western blot analysis. After 48 h of 0.25 μM PHT treatment, appearance of apoptotic cells was detected by TUNEL assay.

RESULTS

PHT treatment decreased the proportion of apoptotic cells in gingival fibroblasts compared to a serum-free control culture in response to the protein changes as follows: PHT upregulated c-FLIP and, in turn, downregulated FADD, caspase-8, and caspase-3; PHT upregulated c-IAP2 and downregulated TRAF2; PHT downregulated caspase-9 and caspase-3 via decreased RIPK1 activity and increased Bcl-2 activity.

CONCLUSION

PHT-induced gingival overgrowth may result from the above-mentioned mechanisms involving apoptosis inhibition in gingival fibroblasts.

Impact on Clinical Outcomes of Periodic Leg Movements During Sleep in Hospitalized Patients Following Acute Decompensated Heart Failure

BACKGROUND

Periodic leg movements during sleep (PLM) are characterized by regularly recurring movement of the legs during sleep. Although PLM is common and a predictor of death in patients with chronic heart failure, the clinical significance of PLM in hospitalized patients with a reduced left ventricular ejection fraction (LVEF) following acute decompensated heart failure (ADHF) remains unknown.Methods and Results:After initial improvement of acute signs and symptoms of ADHF, 94 consecutive patients with reduced LVEF who underwent polysomnography were enrolled. They were divided into 2 groups based on the presence or absence of severe PLM defined as PLM index ≥30. The risks for clinical events, composite of all-cause death and rehospitalization, were assessed using a stepwise multivariable Cox proportional model including variables showing P<0.10 in univariate analyses. Severe PLM was observed in 21 patients (22%). At a median follow-up of 5.2 months, 30 patients experienced clinical events (32%). In the multivariable analysis, the presence of severe PLM was significantly associated with increasing clinical events (hazard ratio, 2.16; 95% confidence interval, 1.03-4.54; P=0.042) independent of hemoglobin level and the severity of sleep-disordered breathing.

CONCLUSIONS

In hospitalized patients with systolic dysfunction following ADHF, severe PLM was prevalent and significantly associated with increased risk of death and/or rehospitalization.

Manganese dioxide nanowires on carbon nanofiber frameworks for efficient electrochemical device electrodes

Hierarchically nanostructured composite electrodes were prepared by the electrodeposition of manganese dioxide nanowires (MnO₂ NWs) with 5–20 nm diameters on electrospun carbon nanofiber (CNF) webs with diameters of 250 and 650 nm.

Utility of serum periostin and free IgE levels in evaluating responsiveness to omalizumab in patients with severe asthma

BACKGROUND

Omalizumab, a humanized anti-IgE monoclonal antibody, has demonstrated efficacy in patients with severe allergic asthma. However, treatment responses vary widely among individuals. Despite a lack of data, free serum IgE levels following omalizumab treatment have been proposed as a marker of treatment responsiveness.

METHODS

In this prospective, observational study, we assessed the utility of biomarkers of type 2 inflammation in predicting omalizumab treatment responses, as determined by the absence of asthma exacerbation during the first year of treatment. Free serum IgE levels were monitored for 2 years to examine their association with baseline biomarker levels and the number of exacerbations.

RESULTS

We enrolled thirty patients who had been treated with omalizumab for at least 1 year, of whom 27 were treated for 2 years. Baseline serum periostin levels and blood eosinophil counts were significantly higher in patients without exacerbations during the first year of treatment than in patients with exacerbations. Baseline serum periostin levels, but not eosinophil counts, were negatively associated with free serum IgE levels after 16 or 32 weeks of treatment. Reduced free serum IgE levels during treatment from those at baseline were associated with reduced exacerbation numbers at 2 years. In 14 patients who continued to have exacerbations during the first year of treatment, exacerbation numbers gradually and significantly decreased over the 2-year study period, with concurrent significant reductions in free serum IgE levels.

CONCLUSION

Baseline serum periostin levels and serum free IgE levels during treatment follow-up may be useful in evaluating responses to omalizumab treatment.