Single-photon property characterization of 1.3 μm emissions from InAs/GaAs quantum dots using silicon avalanche photodiodes

We developed a new approach to test the single-photon emissions of semiconductor quantum dots (QDs) in the optical communication band. A diamond-anvil cell pressure device was used for blue-shifting the 1.3 μm emissions of InAs/GaAs QDs to 0.9 μm for detection by silicon avalanche photodiodes. The obtained g⁽²⁾(0) values from the second-order autocorrelation function measurements of several QD emissions at 6.58 GPa were less than 0.3, indicating that this approach provides a convenient and efficient method of characterizing 1.3 μm single-photon source based on semiconductor materials.

Randomised, double-blind trial of carboplatin and paclitaxel with daily oral cediranib or placebo in patients with advanced non-small cell lung cancer: NCIC Clinical Trials Group study BR29

INTRODUCTION

This randomised double-blind placebo-controlled study evaluated the addition of cediranib, an inhibitor of vascular endothelial growth factor receptors 1-3, to standard carboplatin/paclitaxel chemotherapy in advanced non-small cell lung cancer.

METHODS

Eligible patients received paclitaxel (200mg/m(2)) and carboplatin (area under the concentration time curve 6) intravenously every 3 weeks. Daily oral cediranib/placebo 20mg was commenced day 1 of cycle 1 and continued as monotherapy after completion of 4-6 cycles of chemotherapy. The primary end-point of the study was overall survival (OS). The trial would continue to full accrual if an interim analysis (IA) for progression-free survival (PFS), performed after 170 events of progression or death in the first 260 randomised patients, revealed a hazard ratio (HR) for PFS of ⩽ 0.70.

RESULTS

The trial was halted for futility at the IA (HR for PFS 0.89, 95% confidence interval [CI] 0.66-1.20, p = 0.45). A final analysis was performed on all 306 enrolled patients. The addition of cediranib increased response rate ([RR] 52% versus 34%, p = 0.001) but did not significantly improve PFS (HR 0.91, 95% CI 0.71-1.18, p = 0.49) or OS (HR 0.94, 95% CI 0.69-1.30, p=0.72). Cediranib patients had more grade 3 hypertension, diarrhoea and anorexia.

CONCLUSIONS

The addition of cediranib 20mg daily to carboplatin/paclitaxel chemotherapy increased RR and toxicity, but not survival.

Diagnosis and management of primary umbilical melanoma with omphalitis features

We report on a 62-year-old Chinese male patient who presented with a pigmented lesion in the umbilical area and who was treated for omphalitis in a local hospital for 1 month. Biopsy pathological examination revealed that the lesion was a melanoma. The Breslow depth was estimated at 3 mm, and Clark's level was IV. Ultrasonography showed no suspicious pathological lymph nodes, and no metastases were detected in the lung, liver or brain through CT scans. Reexcision was performed with lateral marginsd >2 cm from the original scar down to the peritoneum, including the umbilicus, round ligament of the liver and urachus. No adjuvant therapy was suggested, and the patient was still alive without recurrences or metastases after 36 months.

Record performance of electrical injection sub-wavelength metallic-cavity semiconductor lasers at room temperature

We demonstrate a continuous wave (CW) sub-wavelength metallic-cavity semiconductor laser with electrical injection at room temperature (RT). Our metal-cavity laser with a cavity volume of 0.67λ3 (λ = 1591 nm) shows a linewidth of 0.5 nm at RT, which corresponds to a Q-value of 3182 compared to 235 of the cavity Q, the highest Q under lasing condition for RT CW operation of any sub-wavelength metallic-cavity laser. Such record performance provides convincing evidences of the feasibility of RT CW sub-wavelength metallic-cavity lasers, thus opening a wide range of practical possibilities of novel nanophotonic devices based on metal-semiconductor structures.

Innovative estimation of survival using log-normal survival modelling on ACCENT database

Background:

The ACCENT database, with individual patient data for 20 898 patients from 18 colon cancer clinical trials, was used to support Food and Drug Administration (FDA) approval of 3-year disease-free survival as a surrogate for 5-year overall survival. We hypothesised substantive differences in survival estimation with log-normal modelling rather than standard Kaplan–Meier or Cox approaches.

Methods:

Time to relapse, disease-free survival, and overall survival were estimated using Kaplan–Meier, Cox, and log-normal approaches for male subjects aged 60–65 years, with stage III colon cancer, treated with 5-fluorouracil-based chemotherapy regimens (with 5FU), or with surgery alone (without 5FU).

Results:

Absolute differences between Cox and log-normal estimates with (without) 5FU varied by end point. The log-normal model had 5.8 (6.3)% higher estimated 3-year time to relapse than the Cox model; 4.8 (5.1)% higher 3-year disease-free survival; and 3.2 (2.2)% higher 5-year overall survival. Model checking indicated greater data support for the log-normal than the Cox model, with Cox and Kaplan–Meier estimates being more similar. All three model types indicate consistent evidence of treatment benefit on both 3-year disease-free survival and 5-year overall survival; patients allocated to 5FU had 5.0–6.7% higher 3-year disease-free survival and 5.3–6.8% higher 5-year overall survival.

Conclusion:

Substantive absolute differences between estimates of 3-year disease-free survival and 5-year overall survival with log-normal and Cox models were large enough to be clinically relevant, and warrant further consideration.

From cirrhosis to hepatocellular carcinoma in HCV-infected patients: genes involved in tumor progression

BACKGROUND

Hepatocellular carcinoma (HCC) is an aggressive tumor with poor prognosis. Understanding molecular changes in hepatocellular carcinoma should improve identification of risk factors in molecular subtypes and provide potential targets for early detection and therapy.

AIM

The present study aimed to analyze the molecular mechanism of the transition from hepatitis C virus (HCV) induced cirrhosis to HCV induced HCC using microarray analysis combined with bioinformatics techniques. METHODS, To accomplish this, we performed the differential coexpression analysis of hepatic gene expression in samples of HCV-cirrhotic patients with and without HCC. Total 465 genes were identified and some of them were used to construct a regulatory network.

RESULTS

Our analysis indicated that several differentially co-express genes might play crucial roles in HCC development, including NA3C2, AHR, MYC, FOXO1 and FOSB. Further analysis predicted these genes might be involved in HCC through pathways of "ribosome", "steroid biosynthesis", "spliceosome" and so on. Moreover, these genes may serve as potential therapeutic targets for the treatment of HCC.

CONCLUSIONS

In conclusion, our findings confirm the presence of multiple molecular alterations during HCV-infected HCC hepatocarcinogenesis and indicate the possibility for identifying prognostic factors associated with HCC progression.

SU-D-BRB-05: Small Animal Lung Compliance Imaging: Assessment System for Tissue Sensitivity to Radiation Induced Lung Injury

PURPOSE

Recent clinical trials and animal studies have indicated that the tissue sensitivity to radiation induced lung injury (RILI) may be region- specific. In this study, we propose a new 4D cone beam CT (CBCT) basedcompliance imaging method to measure regional pulmonary function change in precisely irradiated small animal under CBCT guidance on small animal radiation research platform (SARRP) to facilitate our understanding of region-specific tissue sensitivity to RILI.

METHODS

Four Sprague-Dawley rats underwent prospective pressure gated 4D CBCT on SARRP. Three animals were selected as control group which underwent a second 4D CBCT scan. The fourth animal was irradiated in the central lung (24 Gy) using 3 × 3 mm collimating cone 2 months prior to the scan. The specific compliance (Csp) was calculated via the real time pressure measurement from the ventilator and displacement field from 3D B-spline image registration between the end of inhale and end of exhale phases from the 4D CBCT scan. The 3D Csp maps from the control animal group were mapped to the irradiated animal as a Csp functional atlas for statistical analysis. We alsoevaluated the repeatability of the Csp measurement on a voxel-by-voxel basis.

RESULTS

No significant Csp difference is found after two month of radiation between the irradiated rat (0.22±0.05) and the functional atlas (0.21±0.07). The observation is consistent with previous publications. The averaged linear correlation coefficient between the voxel-by-voxel Csp measurements from initial and repeat scans in control group is 0.98.

CONCLUSIONS

We proposed a method that uses 4D CBCT based compliance imaging to measure region-specific tissue sensitivity of RILI. We compared the irradiated animal two months after radiation with the control group. Our study shows an excellent robustness of the proposed method for regional lung tissue specific compliance measurement. This work was supported in part by UVa George Amorino Pilot Grant.

SU-E-J-192: Static Breath-Hold MRI Based Measurement of Change in Pulmonary Function Following a Course of Radiation Therapy

PURPOSE

Radiation Therapy (RT) induced pulmonary function change may depend on the location, underlying function of that lung prior to radiations, radiation dose/fractionation and other factors. We propose to evaluate the radiation induced pulmonary function change using static breath-hold MRI scans with vascular information and 3D deformable image registration which can provide pulmonary function relative to RT dose on a regional basis.

METHODS

A MRI scan pair near the end of inhale and near the end of exhale with breath hold were acquired for one lung cancer patient before RT and 6 months after RT. The patient was treated with SBRT with 55 Gy to PTVs in the right and the left lung respectively. B-spline based vesselness preserving image registration algorithm was applied to register the MRI pair for the calculation of local lung expansion as a measurement of regional pulmonary function (PF). The PF maps before RT and after RT were then mapped to the planning CT using the same algorithm tuned for MRI-CT registration. The pulmonary function change was calculated via the PF ratio between two MRI pairs.

RESULTS

Strong spatial correlation was found between the irradiated lung region and the region with greatly decreased PF. Based on dose and PFC distribution, no strong determinant factor was found for PF lost in the left lung while the right lung shows that all the lung tissue receiving dose larger than 28 Gy will have a decreased PF.

CONCLUSIONS

We demonstrated a method that uses static breath-hold MRI based lung imaging to evaluate radiation induced pulmonary function change which can be applied to study the dose and the pulmonary function change in a regional basis. This work is supported by NIH grant support 1R21CA144063.