LED-pumped eye-safe pulse laser with an extracavity optical parametric oscillator

An LED-side-pumped Nd:YAG/Cr⁴⁺:YAG passively Q-switched (PQS) laser containing an extracavity optical parametric oscillator (EOPO) is demonstrated. As far as we know, it is the first LED-pumped eye-safe laser. The Nd:YAG pump module is optimized to increase the PQS pulse energy to 24 mJ at 1064 nm. By using a single-pass EOPO design, the output energy of the signal pulse at 1573 nm is 7.44 mJ with a pulse width of 16 ns, the peak power is 434 kW, and the pump-to-signal conversion efficiency is 31%. For double-pass EOPO operation, the pump-to-signal conversion efficiency increases to 45.8%, the output energy of signal pulse is up to 10.98 mJ with a pulse width of 23.5 ns, and the peak power is 459 kW.

The Resolution Rate of Pulmonary Embolism on CT Pulmonary Angiography: a Prospective Study

PURPOSE

To prospectively assess the rate of clot resolution from CT pulmonary angiography (CTPA) in patients with acute pulmonary embolism (PE).

MATERIALS AND METHODS

This prospective cohort study included 290 patients (136 men, 154 women; mean age, 51.9 years) with acute PE. All patients had a CTPA at the presentation and had at least one follow-up within 6 months (mean 72.7 days). Sixty-four percent of patients had follow-up scans for research purposes within a pre-determined period (between 28 and 184 days; mean, 78.27 days) and 36 % had (between 2 and 184 days; mean, 62.78 days) for a clinical indication. The volume of each clot was measured using a semi-automated quantification program. The resolution rate was evaluated by interval-censored analysis.

RESULTS

The overall estimated probability of complete resolution was 42 % at 7 days, 56 % at 10 days, and 71 % at 45 days. Achieving complete resolution was significantly faster in patients with peripheral clots (HR: 1.78; CI: 1.05-3.03, p = 0.032) but slower in patients with consolidation and history of venous thromboembolism (VTE), (HR: 0.37; CI: 0.18-0.79, p = 0.01 and HR: 0.57; CI: 0.35-0.91, p = 0.019, respectively). Although the patients with cancer showed a faster resolution rate (HR: 1.67; CI: 1.05-2.68, p = 0.032), the mortality rate was significantly higher than non-cancer patients.

CONCLUSION

The resolution rate of clot burden in acute PE was associated with patients' clinical presentation variables and CTPA imaging biomarkers. This information may be incorporated into designing a prediction rule and determining the appropriate duration of anticoagulation therapy in patients with acute PE.

Development and verification of the coaxial heterogeneous hyperspectral imaging system

A hyperspectral imaging system (HIS) is a helpful tool that acquires spatial and spectral information from a target. This study developed a coaxial heterogeneous HIS (CHHIS) to collect spectral images with wavelengths ranging from 400 to 1700 nm. In this system, a visible (VIS) spectrometer and a short-wave infrared (SWIR) spectrometer are combined with a coaxial optical path to share the same field of view. This structure reduces the complexity of spatial registration and maintains the scanning duration of two spectrometers as that of a single spectrometer. The spectrometers are also replaceable for extending the detecting spectral range of the system. The calibration methodologies, including spatial correction, spectral calibration, and reflectance calibration, were developed for this system. The signal-to-noise ratio of VIS and SWIR spectrometers in the CHHIS was up to 40 and 60 dB when the exposure time of the VIS and SWIR imaging sensors was 1000 and 10 ms, respectively. When the target distance was at 600 mm, the spatial error of VIS and SWIR images in the scanning direction was less than 1 pixel; these results proved that the system was stable.

Radiometal-Labeled Chitosan Microspheres as Transarterial Radioembolization Agents against Hepatocellular Carcinoma

Transarterial radioembolization (TARE) is an emerging treatment for patients with unresectable hepatocellular carcinoma (HCC). This study successfully developed radiometal-labeled chitosan microspheres (111In/177Lu-DTPA-CMS) with a diameter of 36.5 ± 5.3 μm for TARE. The radiochemical yields of 111In/177Lu-DTPA-CMS were greater than 90% with high radiochemical purities (>98%). Most of the 111In/177Lu-DTPA-CMS were retained in the hepatoma and liver at 1 h after intraarterial (i.a.) administration. Except for liver accumulation, radioactivity in each normal organ was less than 1% of the injected radioactivity (%IA) at 72 h after injection. At 10 days after injection of 177Lu-DTPA-CMS (18.6 ± 1.3 MBq), the size of the hepatoma was significantly reduced by around 81%, while that of the rats in the control group continued to grow. This study demonstrated the effectiveness of 177Lu-DTPA-CMS in the treatment of N1-S1 hepatoma. 111In/177Lu-DTPA-CMS have the potential to be a superior theranostic pair for the treatment of clinical hepatoma.

Gene-editing by CRISPR-Cas9 in combination with anthracycline therapy via tumor microenvironment-switchable, EGFR-targeted, and nucleus-directed nanoparticles for head and neck cancer suppression

Head and neck cancer (HNC) has a high incidence and a poor prognosis. Epirubicin, a topoisomerase inhibitor, is a potential anthracycline chemotherapeutic for HNC treatment. HuR (ELAVL1), an RNA-binding protein, plays a critical role in promoting tumor survival, invasion, and resistance. HuR knockout via CRISPR/Cas9 (HuR CRISPR) is a possible strategy for the simultaneous modulation of the various pathways of tumor progression. Multifunctional nanoparticles modified with pH-sensitive epidermal growth factor receptor (EGFR)-targeting and nucleus-directed peptides were designed for the efficient delivery of HuR CRISPR and epirubicin to human tongue squamous carcinoma SAS cells and SAS tumor-bearing mice. The pH-sensitive nanoparticles responded to the acidic pH value as a switch to expose the targeting peptides. The cellular uptake and transfection efficiency of these nanoparticles in SAS cells increased via EGFR targeting, ligand-mediated endocytosis, and endosomal escape. These nanoparticles showed low cytotoxicity towards normal oral keratinocyte NOK cells. CRISPR/Cas9 was transported into the nucleus via the nuclear directing peptide and successfully knocked out HuR to suppress proliferation, metastasis, and resistance in SAS cells. The multiple inhibition of EGFR/β-catenin/epithelial-mesenchymal transition pathways was mediated through modulating the EGFR/PI3K/mTOR/AKT axis. The co-treatment of epirubicin and HuR CRISPR in SAS cells further facilitated apoptosis/necroptosis/autophagy and caused cancer cell death. In combination with HuR CRISPR nanoparticles, the efficacy and safety of epirubicin nanoparticles against cancer in SAS tumor-bearing mice improved significantly. Collectively, these nanoparticles showed a tumor pH response, active EGFR targeting, and nuclear localization and thus offered a combinatorial spatiotemporal platform for chemotherapy and the CRISPR/Cas gene-editing system.

Lipid polymeric nanoparticles modified with tight junction-modulating peptides promote afatinib delivery across a blood–brain barrier model

Background

Brain metastases from non-small cell lung cancer (NSCLC) remain one of the most challenging malignancies. Afatinib (Afa) is an orally administered irreversible ErbB family blocker approved for epidermal growth factor receptor (EGFR)-mutated NSCLC. However, the incidence of brain metastases in patients with NSCLC and EGFR mutation is high. One of the major obstacles in the treatment of brain metastases is to transport drugs across the blood–brain barrier (BBB). A lipid polymeric nanoparticle (LPN) modified with a tight junction-modulating peptide is a potential formulation to deliver therapeutics across the BBB. FD7 and CCD are short peptides that perturb the tight junctions (TJs) of the BBB. In this study, the use of LPN modified with FD7 or CCD as a delivery platform was explored to enhance Afa delivery across the BBB model of mouse brain-derived endothelial bEnd.3 cells.

Results

Our findings revealed that Afa/LPN-FD7 and Afa/LPN-CCD exhibited a homogeneous shape, a uniform nano-scaled particle size, and a sustained-release profile. FD7, CCD, Afa/LPN-FD7, and Afa/LPN-CCD did not cause a significant cytotoxic effect on bEnd.3 cells. Afa/LPN-FD7 and Afa/LPN-CCD across the bEnd.3 cells enhanced the cytotoxicity of Afa on human lung adenocarcinoma PC9 cells. FD7 and CCD-modulated TJ proteins, such as claudin 5 and ZO-1, reduced transendothelial electrical resistance, and increased the permeability of paracellular markers across the bEnd.3 cells. Afa/LPN-FD7 and Afa/LPN-CCD were also partially transported through clathrin- and caveolae-mediated transcytosis, revealing the effective activation of paracellular and transcellular pathways to facilitate Afa delivery across the BBB and cytotoxicity of Afa on PC9 cells.

Conclusion

TJ-modulating peptide-modified LPN could be a prospective platform for the delivery of chemotherapeutics across the BBB to the brain for the potential treatment of the BM of NSCLC.

Intercomparison of conventional and QuickScan dicentric scoring for the validation of individual biodosimetry analysis in Taiwan

PURPOSE

The dicentric chromosome assay (DCA), the gold standard for radiation biodosimetry, evaluates an individual absorbed radiation dose by the analysis of DNA damage in human lymphocytes. The conventional (C-DCA) and QuickScan (QS-DCA) scoring methods are sensitive for estimating radiation dose. The Biodosimetry Laboratory at Institute of Nuclear Energy Research (INER), Taiwan, participated in intercomparison exercises conducted by Health Canada (HC) in 2014, 2015 and 2018 to validate the laboratory's accuracy and performance.

MATERIAL AND METHODS

Blood samples for the conventional dose response curve for Taiwan were irradiated with 0, 0.25, 0.5, 1, 2, 3, 4 and 5 Gy. Ten blind blood samples were provided by HC. Either or both of two methods of conventional (C) or QuickScan (QS) scoring could be chosen for the HC's intercomparison. For C-DCA triage scoring, only cells with 46 centromeres were counted and each scorer recorded the number of dicentrics in the first 50 metaphases or stopped scoring when 30 dicentrics were reached. Scorers also recorded how much time it took to analyze 10, 20, and 50 cells. Subsequently, the data were entered into the Dose Estimate software (DoseEstimate_v5.1) and dose estimates were calculated. With QS-DCA scoring, a minimum of 50 metaphase cells (or 30 dicentrics) were scored in apparently complete metaphases without verification of exactly 46 centromeres.

RESULTS

For the blinded blood samples irradiated at HC and shipped to INER, the mean absolute deviation (MAD) derived after scoring 50 cells for C-DCA and QS-DCA was <0.5 Gy for all three intercomparisons, meeting the criteria for acceptance.

CONCLUSION

The results indicated that the Biodosimetry Laboratory at INER can provide reliable dose estimates in the case of a large-scale radiation accident.

Molecular Imaging and Preclinical Studies of Radiolabeled Long-Term RGD Peptides in U-87 MG Tumor-Bearing Mice

The Arg–Gly–Asp (RGD) peptide shows a high affinity for α_vβ₃ integrin, which is overexpressed in new tumor blood vessels and many types of tumor cells. The radiolabeled RGD peptide has been studied for cancer imaging and radionuclide therapy. We have developed a long-term tumor-targeting peptide DOTA-EB-cRGDfK, which combines a DOTA chelator, a truncated Evans blue dye (EB), a modified linker, and cRGDfK peptide. The aim of this study was to evaluate the potential of indium-111(¹¹¹In) radiolabeled DOTA-EB-cRGDfK in α_vβ₃ integrin-expressing tumors. The human glioblastoma cell line U-87 MG was used to determine the in vitro binding affinity of the radiolabeled peptide. The in vivo distribution of radiolabeled peptides in U-87 MG xenografts was investigated by biodistribution, nanoSPECT/CT, pharmacokinetic and excretion studies. The in vitro competition assay showed that ¹¹¹In-DOTA-EB-cRGDfK had a significant binding affinity to U-87 MG cancer cells (IC₅₀ = 71.7 nM). NanoSPECT/CT imaging showed ¹¹¹In-DOTA-EB-cRGDfK has higher tumor uptake than control peptides (¹¹¹In-DOTA-cRGDfK and ¹¹¹In-DOTA-EB), and there is still a clear signal until 72 h after injection. The biodistribution results showed significant tumor accumulation (27.1 ± 2.7% ID/g) and the tumor to non-tumor ratio was 22.85 at 24 h after injection. In addition, the pharmacokinetics results indicated that the ¹¹¹In-DOTA-EB-cRGDfK peptide has a long-term half-life (T_1/2λz = 77.3 h) and that the calculated absorbed dose was safe for humans. We demonstrated that radiolabeled DOTA-EB-cRGDfK may be a promising agent for glioblastoma tumor imaging and has the potential as a theranostic radiopharmaceutical.

Preclinical Evaluation of Recombinant Human IL15 Protein Fused with Albumin Binding Domain on Anti-PD-L1 Immunotherapy Efficiency and Anti-Tumor Immunity in Colon Cancer and Melanoma

Simple Summary

In this manuscript, we reported that a newly developed recombinant human IL15 fused with albumin binding domain (hIL15-ABD) showed superior biological half-life, pharmacokinetic and anti-tumor immunity than wild-type (WT) hIL15. Our hIL-15-ABD can effectively enhance anti-tumor efficacy of anti-PD-L1 on colon cancer and melanoma animal models. The anti-tumor potential of hIL-15-ABD was associated with tumor microenvironment (TME) regulation, including the activation of NK cells and CD8⁺ T cells, the reduction of immunosuppressive cells (MDSCs and Tregs) and the suppression of immunosuppressive factors (IDO, FOXP3 and VEGF). In conclusion, our new hIL15-ABD combined with anti-PD-L1 antibody increased the activity of anti-tumor effector cells involved in both innate and adaptive immunities, decreased the TME’s immunosuppressive cells, and showed greater anti-tumor effect than that of either monotherapy. We suggested hIL15-ABD as the potential complementary agent may effectively augment the therapeutic efficacy of anti-PD-L1 antibody in colon cancer and melanoma model.

Abstract

Anti-PD-L1 antibody monotherapy shows limited efficacy in a significant proportion of the patients. A common explanation for the inefficacy is a lack of anti-tumor effector cells in the tumor microenvironment (TME). Recombinant human interleukin-15 (hIL15), a potent immune stimulant, has been investigated in clinical trial with encouraging results. However, hIL15 is constrained by the short half-life of hIL15 and a relatively unfavorable pharmacokinetics profile. We developed a recombinant fusion IL15 protein composed of human IL15 (hIL15) and albumin binding domain (hIL15-ABD) and explored the therapeutic efficacy and immune regulation of hIL-15, hIL15-ABD and/or combination with anti-PD-L1 on CT26 murine colon cancer (CC) and B16-F10 murine melanoma models. We demonstrated that hIL15-ABD has significant inhibitory effect on the CT26 and B16-F10 tumor growths as compared to hIL-15. hIL-15-ABD not only showed superior half-life and pharmacokinetics data than hIL-15, but also enhance anti-tumor efficacy of antibody against PD-L1 via suppressive effect on accumulation of Tregs and MDSCs and activation of NK and CD8+T cells. Immune suppressive factors including VEGF and IDO were also decreased by combination treatment. hIL15-ABD combined with anti-PD-L1 antibody increased the activity of anti-tumor effector cells involved in both innate and adaptive immunities, decreased the TME’s immunosuppressive cells, and showed greater anti-tumor effect than that of either monotherapy.

Evaluation of Radioiodinated Fluoronicotinamide/Fluoropicolinamide-Benzamide Derivatives as Theranostic Agents for Melanoma

Malignant melanoma is the most harmful type of skin cancer and its incidence has increased in this past decade. Early diagnosis and treatment are urgently desired. In this study, we conjugated picolinamide/nicotinamide with the pharmacophore of ¹³¹I-MIP-1145 to develop ¹³¹I-iodofluoropicolinamide benzamide (¹³¹I-IFPABZA) and ¹³¹I-iodofluoronicotiamide benzamide (¹³¹I-IFNABZA) with acceptable radiochemical yield (40 ± 5%) and high radiochemical purity (>98%). We also presented their biological characteristics in melanoma-bearing mouse models. ¹³¹I-IFPABZA (Log P = 2.01) was more lipophilic than ¹³¹I-IFNABZA (Log P = 1.49). B16F10-bearing mice injected with ¹³¹I-IFNABZA exhibited higher tumor-to-muscle ratio (T/M) than those administered with ¹³¹I-IFPABZA in planar γ-imaging and biodistribution studies. However, the imaging of ¹³¹I-IFNABZA- and ¹³¹I-IFPABZA-injected mice only showed marginal tumor uptake in A375 amelanotic melanoma-bearing mice throughout the experiment period, indicating the high binding affinity of these two radiotracers to melanin. Comparing the radiation-absorbed dose of ¹³¹I-IFNABZA with the melanin-targeted agents reported in the literature, ¹³¹I-IFNABZA exerts lower doses to normal tissues on the basis of similar tumor dose. Based on the in vitro and in vivo studies, we clearly demonstrated the potential of using ¹³¹I-IFNABZA as a theranostic agent against melanoma.

PEG-coated nanoparticles detachable in acidic microenvironments for the tumor-directed delivery of chemo- and gene therapies for head and neck cancer

Background: Head and neck cancer (HNC) is a major cause of morbidity and mortality and has a poor treatment outcome. Irinotecan, a topoisomerase-I inhibitor, induces cell death by decreasing the religation of double-strand DNA. However, epithelial-mesenchymal transition (EMT), therapy resistance, and systemic toxicity caused by available antineoplastic agents hinder the efficacy and safety of HNC treatment. Chemotherapy combined with gene therapy shows potential application in circumventing therapy resistance and EMT. miR-200 exerts a remarkable suppressing effect on EMT-associated genes. Herein, liposomes and solid lipid nanoparticles (SLNs) modified with a pH-sensitive, self-destructive polyethylene glycol (PEG) shell and different peptides were designed as irinotecan and miR-200 nanovectors to enhance tumor-specific accumulation. These peptides included one ligand targeting the angiogenic tumor neovasculature, one mitochondrion-directed apoptosis-inducing peptide, and one cell-penetrating peptide (CPP) with high potency and selectivity toward cancer cells. Methods: Physicochemical characterization, cytotoxicity analysis, cellular uptake, regulation mechanisms, and in vivo studies on miR-200- and irinotecan-incorporated nanoparticles were performed to identify the potential antitumor efficacy and biosafety issues involved in HNC treatment and to elucidate the underlying signaling pathways. Results: We found that the cleavable PEG layer responded to low extracellular pH, and that the CPP and targeting peptides were exposed to improve the uptake and release of miR-200 and irinotecan into HNC human tongue squamous carcinoma (SAS) cells. The apoptosis of SAS cells treated with the combinatorial therapy was significantly induced by regulating various pathways, such as the Wnt/β-catenin, MDR, and EMT pathways. The therapeutic efficacy and safety of the proposed co-treatment outperformed the commercially available Onivyde and other formulations used in a SAS tumor-bearing mouse model in this study. Conclusion: Chemotherapy and gene therapy co-treatment involving pH-sensitive and targeting peptide-modified nanoparticles may be an innovative strategy for HNC treatment.

Imaging and biodistribution of radiolabeled SP90 peptide in BT-483 tumor bearing mice

The objective of this study was to evaluate radiolabeled DOTA-SP90 as a radiotracer for breast cancer. The in vitro competition assay showed that radiolabeled DOTA-SP90 had significant binding affinity to BT-483 cancer cells. Biodistribution, nanoSPECT/CT and nanoPET/CT imaging results indicated that radiolabeled DOTA-SP90 can accumulate in tumors. In addition, radiolabeled DOTA-SP90 peptides can also detect metastatic tumors. Therefore, radiolabeled SP90 peptide may provide the potential capability as diagnostic agent for breast cancer patients.

Examining the association between oral health status and dementia: A nationwide nested case-controlled study

Alzheimer’s disease as a consequence of chronic brain inflammation mediated by infectious microbes including the oral microbiome continues to attract support. Taiwan’s National Insurance database was used to evaluate associations between dental health and Alzheimer’s disease; 209,112 new cases of Alzheimer’s disease were matched 1:4 with 836,448 dementia-free controls to test the hypothesis that better dental health would be associated with less occurrence of dementia. Ten year dental records and conditional logistic regression models were used to estimate the odds ratios associated with Alzheimer’s disease. Subgroup analyses compared vascular Alzheimer’s disease and sporadic Alzheimer’s disease. As the population aged, Alzheimer’s disease diagnoses were more frequent with a 10 fold upward inflection after 60. Nearly 56% of sporadic Alzheimer’s disease patients were women but less than 50% had vascular Alzheimer’s disease. Comorbidities were 10–20% higher in the Alzheimer’s disease patients than in controls, but stroke, chronic infection, and pneumonia were 40–45% more common in the vascular Alzheimer’s disease patients. Heart disease, hypertension, diabetes, stroke, peripheral artery disease, pneumonia, and herpetic disease (HSV) were all associated with higher odds of Alzheimer’s disease. HSV was not a factor in the vascular Alzheimer’s disease. Routine dental procedures tended to lower odds ratios. Root canals and extractions that restore oral homeostasis were associated with lower odds of dementia. However, when extractions exceeded four, the odds of Alzheimer’s disease rose. The fact that Alzheimer’s disease was not associated with periodontal procedures per se but with more frequent periodontal emergencies suggested again a chronic issue. Dental health costs suggest that good dental care was associated with lower odds of Alzheimer’s disease except for radiographic costs which were consistently associated with higher odds, independent of oral health. Common comorbid conditions were associated with higher odds of Alzheimer’s disease and oral health care was associated with lower odds, providing support for the hypothesis that the oral microbiome is a factor in the development of Alzheimer’s disease.

Impact statement

This study clearly demonstrates the power and value of a nationally applied digital medical record. Longitudinal studies of gradually developing pathologies like dementia have often been limited by sample size and narrow and incomplete medical histories. The Taiwan National Insurance database provides an unparalleled opportunity for detailed analyses of associations between current medical conditions and a spectrum of prior medical and dental events. The temporal impact of the database will only become more important as the past historical record progressively expands going forward. The inclusion of dental records in assessing the relationship with subsequent dementia is very important because this information is often unavailable or dependent on subject recall. This study clearly establishes associations between a variety of suspected cardiovascular and metabolic factors and the odds of dementia. A critical outcome should include the design of targeted interventions and the subsequent assessment of their efficacy.

Investigation of biodistribution and tissue penetration of PEGylated gold nanostars and their application for photothermal cancer treatment in tumor-bearing mice

PEGylated gold nanostars (pAuNSs) and their radioactive surrogate (¹¹¹In–DTPA–pAuNS), with unique physiochemical properties, are thought to be a promising agent for image-guided photothermal therapy (PTT).

pH-Responsive PEG-Shedding and Targeting Peptide-Modified Nanoparticles for Dual-Delivery of Irinotecan and microRNA to Enhance Tumor-Specific Therapy

Irinotecan is one of the main chemotherapeutic agents for colorectal cancer (CRC). MicroRNA-200 (miR-200) has been reported to inhibit metastasis in cancer cells. Herein, pH-sensitive and peptide-modified liposomes and solid lipid nanoparticles (SLN) are designed for encapsulation of irinotecan and miR-200, respectively. These peptides include one cell-penetrating peptide, one ligand targeted to tumor neovasculature undergoing angiogenesis, and one mitochondria-targeting peptide. The peptide-modified nanoparticles are further coated with a pH-sensitive PEG-lipid derivative with an imine bond. These specially-designed nanoparticles exhibit pH-responsive release, internalization, and intracellular distribution in acidic pH of colon cancer HCT116 cells. These nanoparticles display low toxicity to blood and noncancerous intestinal cells. Delivery of miR-200 by SLN further increases the cytotoxicity of irinotecan-loaded liposomes against CRC cells by triggering apoptosis and suppressing RAS/β-catenin/ZEB/multiple drug resistance (MDR) pathways. Using CRC-bearing mice, the in vivo results further indicate that irinotecan and miR-200 in pH-responsive targeting nanoparticles exhibit positive therapeutic outcomes by inhibiting colorectal tumor growth and reducing systemic toxicity. Overall, successful delivery of miR and chemotherapy by multifunctional nanoparticles may modulate β-catenin/MDR/apoptosis/metastasis signaling pathways and induce programmed cancer cell death. Thus, these pH-responsive targeting nanoparticles may provide a potential regimen for effective treatment of colorectal cancer.

A DNA Aptamer Targeting Galectin-1 as a Novel Immunotherapeutic Strategy for Lung Cancer

Galectin-1 (Gal-1) is a pleiotropic homodimeric β-galactoside-binding protein with a single carbohydrate recognition domain. It has been implicated in several biological processes that are important during tumor progression. Several lines of evidence have indicated that Gal-1 is involved in cancer immune escape and induces T cell apoptosis. These observations all emphasized Gal-1 as a novel target for cancer immunotherapy. Here, we developed a novel Gal-1-targeting DNA aptamer (AP-74 M-545) and demonstrated its antitumor effect by restoring immune function. AP-74 M-545 binds to Gal-1 with high affinity. AP-74 M-545 targets tumors in murine tumor models but suppresses tumor growth only in immunocompetent C57BL/6 mice, not in immunocompromised non-obese diabetic (NOD)/severe combined immunodeficiency (SCID) mice. Immunohistochemistry revealed increased CD4⁺ and CD8⁺ T cells in AP-74 M-545-treated tumor tissues. AP-74 M-545 suppresses T cell apoptosis by blocking the binding of Gal-1 to CD45, the main receptor and apoptosis mediator of Gal-1 on T cells. Collectively, our data suggest that the Gal-1 aptamer suppresses tumor growth by blocking the interaction between Gal-1 and CD45 to rescue T cells from apoptosis and restores T cell-mediated immunity. These results indicate that AP-74 M-545 may be a potential strategy for cancer immunotherapy.

Abstract 1803: Openarray profiling of the systemic change of microRNAs in rhenium-188 liposome treated human head and neck cancer cells

Purpose188Re-liposome has been used for evaluating the theranostic efficacy in various human cancers. However, whether the therapeutic efficacy of 188Re-liposome directly related to microRNAs regulation and specific signaling pathways are largely unknown. In this project, we investigated the 188Re-liposome induced systemic microRNA expressive responses in human head and neck cancer (HNSCC) cells.

Methods

The FaDu-3R cells were implanted into the nude mice at the position of buccal cavity. After two weeks of implantation, the tumors were palpable and the bioluminescent imaging indicated the location of this orthotopic tumor model. The PEGylated 188Re-liposome was intravenously injected single and dual dose respectively. We harvested all of the tumors after 188Re-liposome injection one month ago, and used Taqman Openarray MicroRNA (Thermo, USA) to detect the expression of miRNAs in different groups. The dataset we observed was further analyzed by using Ingenuity Pathway Analysis (IPA) software to establish the molecular signaling pathway of 188Re-liposome radiopharmaceutical.

Results

Quantification of the photon signals showed that the tumor growth of the dual 188Re-liposome treated mice was slower than that of control ones. The survival rate of 188Re-liposome treated animals were also better than control ones. The microRNA Openarray showed that, compared to untreated control, 17 miRNA were significantly changed in expressive levels over 5 fold after 188Re-liposome treatment. Subsequently, we used IPA to determine the role of these miRNA, and found these miRNA with oncogenic and tumor suppressive properties were down-regulated and up-regulated, respectively. Among them, we focused on miR-152-5p that is closed related to cancer occurrence and development, and showed that knockdown of miR-152-5p could decreased the effects of 188Re-liposome on suppressing the growth of HNSCC xenograft tumors.

Conclusion

HNSCC tumor model treated with dual dose of 188Re-liposome exhibited significant response to this radiopharmaceutical. We also found that 17 miRNA could be gsignificantly re-regulated, and miR-152-5p is one example to be involved in mediating the efficacy of 188Re-liposome. Targeting on specific miRNA may enhance the application value of 188Re-liposome.in cancer treatment.

Citation Format: Bing-Ze Lin, Chun-Yuan Chang, Chih-Hsien Chang, Yi-Jang Lee. Openarray profiling of the systemic change of microRNAs in rhenium-188 liposome treated human head and neck cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1803.

Endothelial Cell-Targeted Deletion of PPARγ Blocks Rosiglitazone-Induced Plasma Volume Expansion and Vascular Remodeling in Adipose Tissue

Thiazolidinediones (TZDs) are peroxisome proliferator-activated receptor γ (PPARγ) agonists that represent an effective class of insulin-sensitizing agents; however, clinical use is associated with weight gain and peripheral edema. To elucidate the role of PPARγ expression in endothelial cells (ECs) in these side effects, EC-targeted PPARγ knockout (Pparg ΔEC) mice were placed on a high-fat diet to promote PPARγ agonist-induced plasma volume expansion, and then treated with the TZD rosiglitazone. Compared with Pparg-floxed wild-type control (Pparg f/f) mice, Pparg ΔEC treated with rosiglitazone are resistant to an increase in extracellular fluid, water content in epididymal and inguinal white adipose tissue, and plasma volume expansion. Interestingly, histologic assessment confirmed significant rosiglitazone-mediated capillary dilation within white adipose tissue of Pparg f/f mice, but not Pparg ΔEC mice. Analysis of ECs isolated from untreated mice in both strains suggested the involvement of changes in endothelial junction formation. Specifically, compared with cells from Pparg f/f mice, Pparg ΔEC cells had a 15-fold increase in focal adhesion kinase, critically important in EC focal adhesions, and >3-fold significant increase in vascular endothelial cadherin, the main component of focal adhesions. Together, these results indicate that rosiglitazone has direct effects on the endothelium via PPARγ activation and point toward a critical role for PPARγ in ECs during rosiglitazone-mediated plasma volume expansion.

Radiolabeling, Characteristics and NanoSPECT/CT Imaging of 188Re-cetuximab in NCI-H292 Human Lung Cancer Xenografts

BACKGROUND/AIM

Cetuximab has exhibited high EGFR-targeting specificity and clinical promise in previous studies. In this study, we formulated unit dose kits for preparation of high specific activity ¹⁸⁸Re-cetuximab for imaging and treatment of EGFR-positive cancer.

MATERIALS AND METHODS

¹⁸⁸Re-cetuximab was prepared by adding 0.37-0.74 GBq/0.5 ml of ¹⁸⁸Re-perrhenate for 4 h at 37°C. Cell surface expression of EGFR, cell binding and cytotoxic effects were evaluated in vitro using both EGFR-positive (NCI-H292, A431) and EGFR-negative (BT483) tumors. A nanoSPECT/CT imaging study was performed in mice bearing EGFR-expressing NCI-H292 tumors.

RESULTS

¹⁸⁸Re-cetuximab bound specifically to EGFR-expressing cells and labeling of radionuclides to cetuximab preserved the binding ability of the antibody. Besides, the cytotoxic effect of ¹⁸⁸Re-cetuximab was increased dose-dependently. NanoSPECT/CT imaging revealed that ¹⁸⁸Re-cetuximab could continually target the tumor region for at least 48 h.

CONCLUSION

The highly specific targeted property of ¹⁸⁸Re-cetuximab suggested that it is suitable as a diagnostic tool and maybe a potent radioimmunotherapy agent in EGFR-positive cancers.

Biodistribution, pharmacokinetics and radioimmunotherapy of 188Re-cetuximab in NCI-H292 human lung tumor-bearing nude mice

Background Cetuximab is a fully humanized IgG1 subclass monoclonal that binds specifically to the human epidermal growth factor receptor (EGFR). Although EGFR is expressed in normal cells, the overexpression of EGFR is detected in many human cancers, such as colon, rectum and lung tumors. In this study, cetuximab with a combination of radiotherapy nuclear ¹⁸⁸Re achieved better therapeutic effect on lung cancer. Methods¹⁸⁸Re-cetuximab administered by the i.v. route in human NCI-H292 lung tumor-bearing mice was investigated. NanoSPECT/CT images were taken to evaluate the distribution and tumor targeting of ¹⁸⁸Re-cetuximab in mice. The anti-tumor effect of ¹⁸⁸Re-cetuximab was assessed by the tumor growth inhibition, survival ratio. Results For nanoSPECT/CT imaging, a significant uptake in tumor was observed at 24 and 48 h following the injection of ¹⁸⁸Re-cetuximab. The anti-tumor effect of ¹⁸⁸Re-cetuximab was assessed by tumor growth inhibition and the survival ratio. The tumor-bearing mice treated with ¹⁸⁸Re-cetuximab showed a better mean tumor growth inhibition rate (MGI = 0.049) and longer median survival time and lifespan (62.50 d; 70.07%) than those treated with ¹⁸⁸Re-perrhenate and cetuximab only by single injection. A synergistic effect of tumor growth inhibition was observed with the combination index exceeding one for ¹⁸⁸Re-cetuximab (CI = 6.135 and 9.276). Conclusion The tumor targeting and localization of 188Re-cetuximab were confirmed in this study. Synergistic therapeutic efficacy was demonstrated for the radioimmunotherapy of ¹⁸⁸Re-cetuximab. The results of this study reveal the potential advantage and benefit obtained from ¹⁸⁸Re-cetuximab for diagnosis and therapy of oncology applications in the future.

Potential human exposures to neonicotinoid insecticides: A review

Due to their systemic character and high efficacy to insect controls, neonicotinoid insecticides (neonics) have been widely used in global agriculture since its introduction in early 1990. Recent studies have indicated that neonics may be ubiquitous, have longer biological half-lives in the environment once applied, and therefore implicitly suggested the increasing probability for human exposure to neonics. Despite of neonics' persistent characters and widespread uses, scientific literature in regard of pathways in which human exposure could occur is relatively meager. In this review, we summarized results from peer-reviewed articles published prior to 2017 that address potential human exposures through ingestion and inhalation, as well as results from human biomonitoring studies. In addition, we proposed the use of relative potency factor approach in order to facilitate the assessment of concurrent exposure to a mixture of neonics with similar chemical structures and toxicological endpoints. We believe that the scientific information that we presented in this review will aid to future assessment of total neonic exposure and subsequently human health risk characterization.

Biodistribution, Pharmacokinetics and Efficacy of 188Re(I)-Tricarbonyl-Labeled Human Serum Albumin Microspheres in an Orthotopic Hepatoma Rat Model

BACKGROUND/AIM

The biodistribution, pharmacokinetics and therapeutic evaluation of ¹⁸⁸Re-human serum albumin microspheres (¹⁸⁸Re-HSAM) by labeling with ¹⁸⁸Re(I)-tricarbonyl ion (¹⁸⁸Re(OH₂)₃(CO)₃)+) were investigated in a GP7TB orthotopic hepatoma rat model.

MATERIALS AND METHODS

Male F344 rats received intrahepatic inoculations with GP7TB 1 mm3 cubes. The efficacy of ¹⁸⁸Re-HSAM was examined following a single-dose treatment via the intraarterial route. Rats were monitored for survival until death.

RESULTS

The labeling efficiency of the ¹⁸⁸Re-HSAM was about 80%. After intraarterial administration of ¹⁸⁸Re-HSAM, radioactivity in tumors accumulated from 18.41±3.48 %ID/g at 1 h to 12.43±4.70 %ID/g at 24 h. The tumor/liver ratios ranged from 3.03 at 1 h to 1.89 at 72 h. The major uptake organs of ¹⁸⁸Re-HSAM were liver (73.35%ID to 48.92%ID), tumor (10.54%ID to 3.51%ID) and kidney (7.48 %ID to 0.14%ID). The T_1/2λz of ¹⁸⁸Re-HSAM was 259.34 h after intraarterial injection. The AUC_{(0→96 h)} of ¹⁸⁸Re-HSAM was 0.69 h*% ID/g. In the efficacy study, the median survival time for the rat (n=6), that received normal saline was 80 d. The median survival times for the mice treated with 10 mCi (n=4), 5.2 mCi (n=6) and 2.9 mCi (n=3) of ¹⁸⁸Re-HSAM were 130 d (p=0.003), 106 d (p=0.002) and 83.5 d (p=0.617), respectively. The increase in life span of 10 mCi, 5.2 mCi and 2.9 mCi of ¹⁸⁸Re-HSAM were 62.5%, 32.5% and 4.4%, respectively.

CONCLUSION

Administration of ¹⁸⁸Re-HSAM demonstrated better survival time and therapeutic efficacy at the higher dose in the GP7TB hepatoma model. These results suggested that intraarterial administration of ¹⁸⁸Re-HSAM could provide a benefit and promising strategy for delivery of radiotherapeutics in oncology applications.

Involvement of let-7 microRNA for the therapeutic effects of Rhenium-188-embedded liposomal nanoparticles on orthotopic human head and neck cancer model

Human head and neck squamous cell carcinoma (HNSCC) is usually treated by surgical resection with adjuvant radio-chemotherapy. In this study, we examined whether the radiopharmaceutical ¹⁸⁸Re-liposome could suppress the growth of HNSCC followed by an investigation of molecular mechanisms. The orthotopic HNSCC tumor model was established by human hypopharyngeal FaDu carcinoma cells harboring multiple reporter genes. The drug targeting and therapeutic efficacy of ¹⁸⁸Re-liposome were examined using in vivo imaging, bio-distribution, pharmacokinetics, and dosimetry. The results showed that ¹⁸⁸Re-liposome significantly accumulated in the tumor lesion compared to free ¹⁸⁸Re. The circulation time and tumor targeting of ¹⁸⁸Re-liposome were also longer than that of free ¹⁸⁸Re in tumor-bearing mice. The tumor growth was suppressed by ¹⁸⁸Re-liposome up to three weeks using a single dose treatment. Subsequently, microarray analysis followed by Ingenuity Pathway Analysis (IPA) showed that tumor suppressor let-7 microRNA could be an upstream regulator induced by ¹⁸⁸Re-liposome to regulate downstream genes. Additionally, inhibition of let-7i could reduce the effects of ¹⁸⁸Re-liposome on suppression of tumor growth, suggesting that let-7 family was involved in ¹⁸⁸Re-liposome mediated suppression of tumor growth in vivo. Our data suggest that ¹⁸⁸Re-liposome could be a novel strategy for targeting HNSCC partially via induction of let-7 microRNA.

Elevated Aminotransferases are Predictors of Hepatic Injury in Blunt Abdominal Trauma Patients

Objective

Computed tomography (CT) scan is currently the most commonly used tool for evaluating solid-organ injuries in trauma management. However, liberal use of CT scanning increases the risk of excess radiation exposure and toxicity from contrast material. Animal studies and clinical research on the paediatric population indicated that liver enzymes elevations were related to hepatic injury. The present study was undertaken to determine whether elevated liver enzymes were associated with the occurrence of hepatic injury in adult patients with blunt abdominal trauma.

Methods

This is a cross-sectional study from August 2003 to October 2006. All adult patients with blunt injury to abdomino-pelvic organs documented by CT or surgery who were admitted to Chi-Mei Medical Centre in the captioned period were included. The study population sorted to hepatic injury (HI) and no hepatic injury (NHI) groups according to the presence or absence of hepatic injury. Variables including liver enzymes were compared between the groups.

Results

Totally 419 patients were included, including 150 patients in the HI group and 269 patients in the NHI group. The HI group was younger and had a lower rate of laparotomy (36.3 years old vs 41.4 years old; 26% vs 42%, respectively). The mean levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the HI group were significantly higher than levels in the NHI group (439.6 IU/L vs 104.7 IU/L; 353.5 IU/L vs 76.6 IU/L, p<0.01). We define AST >200 IU/L or ALT level >125 IU/L as abnormal according to previous studies. The diagnostic characteristics of hepatic injury were 87.3% sensitivity, 80.3% specificity, 71.2% positive predictive value, and 91.9% negative predictive value.

Conclusion

In adults who have experienced blunt abdominal trauma, AST >200 U/L or of ALT >125 U/L are practical predictors of hepatic injury. Screening serum aminotransferases will have a role in detecting occult hepatic injury and may reduce the hazards of excessive CT scanning. (Hong Kong j.emerg.med. 2013;20:337-342)

An Evaluation of the ACEP Guideline for Mild Head Injuries in Taiwan

Introduction

Traumatic brain injury (TBI) is an important issue in the emergency department. In the United States, the American College of Emergency Physicians (ACEP) published clinical guideline to select patients with mild head injuries for head computed tomography (CT) scans in 2008. The aim of this study was to identify the possible benefits of compliance with these guidelines for mild head injury patients in Taiwan.

Method

This was a secondary analysis on our previous study published for association of hypertension and head injuries. In our previous study, we collected data about 1290 patients with head injuries who received brain CT scans in the emergency department from September 2012 to August 2013 for a study regarding the association between head injury and hypertension. In present study, we subjected this data to further analysis to try to validate the ACEP clinical policy for mild head injuries.

Results

Of these 1,290 patients, 154 were found to have brain haemorrhage on the initial brain CT scan, and 5 were in need of neurosurgical intervention. A total of 859 patients met the ACEP guideline criteria, and 117 of these had brain haemorrhages. The sensitivity and specificity of the ACEP guideline to predict brain haemorrhage were 75.97% (95% confidence interval [CI], 68.44% to 82.48%) and 34.68% (95% CI, 31.91% to 37.53%), respectively. In predicting neurosurgical intervention, the sensitivity and specificity of the guideline were 100% (95% CI, 47.82% to 100%) and 33.54% (95% CI, 30.96% to 36.2%), respectively.

Conclusion

Although adoption of the ACEP clinical policy may reduce the number of brain CT scans in mild head injury patients who may need neurosurgical interventions, it is not a good selection tool in Taiwan.

Gamma-Secretase Inhibitors Attenuate Neurotrauma and Neurogenic Acute Lung Injury in Rats by Rescuing the Accumulation of Hypertrophic Microglia

Background/Aims: In response to traumatic brain injury (TBI), activated microglia exhibit changes in their morphology from the resting ramified phenotype toward the activated hypertrophic or amoeboid phenotype. Here, we provide the first description of the mechanism underlying the neuroprotective effects of γ-secretase inhibitors on TBI outcomes in rats. Methods: The neuroprotective effects of γ-secretase inhibitors such as LY411575 or CHF5074 on TBI-induced neurotoxicity were analysed using a neurological motor function evaluation, cerebral contusion assay, immunohistochemical staining for microglia phenotypes, lung injury score and Evans Blue dye extravasation assay of brain and lung oedema. Results: Hypertrophic or amoeboid microglia accumulated in the injured cortex, the blood-brain-barrier was disrupted and neurological deficits and acute lung injury were observed 4 days after TBI in adult rats. However, a subcutaneous injection of LY411575 (5 mg/kg) or CHF5074 (30 mg/kg) immediately after TBI and once daily for 3 consecutive days post-TBI significantly attenutaed the accumulation of hypertrophic microglia in the injured brain, neurological injury, and neurogenic acute lung injury. Conclusion: Gamma-secretase inhibitors attenuated neurotrauma and neurogenic acute lung injury in rats by reducing the accumulation of hypertrophic microglia in the vicinity of the lesion.

Imaging, biodistribution and efficacy evaluation of 188Re-human serum albumin microspheres via intraarterial route in an orthotopic hepatoma model

PURPOSE

Liver cancer is the second most common cause of death worldwide. This study was to investigate the SPECT/CT, ultrasound, biodistribution and therapeutic evaluation of ¹⁸⁸Re-human serum albumin microspheres (¹⁸⁸Re-HSAM) in the GP7TB orthotopic hepatoma rat model.

MATERIALS AND METHODS

HSAM was labeled with ¹⁸⁸Re by using a home-made kit and microwave system. The ¹⁸⁸Re-HSAM was administered via intraarterial route. The in vivo distribution of ¹⁸⁸Re-HSAM was determined by biodistribution analysis and nanoSPECT/CT system. In efficacy, tumor volumes were tracked longitudinally by three-dimensional ultrasound.

RESULTS

The biodistribution and nanoSPECT/CT imaging showed that ¹⁸⁸Re-HSAM could accumulate in liver and tumor. The correlation coefficient of tumor volumes done by three-dimensional ultrasound and at autopsy was 0.997. In efficacy, tumor volume in the normal saline-treated group was 1803.2 mm³ at 54 days after tumor inoculation. Tumor volumes in the 103.6 MBq and 240.5 MBq of ¹⁸⁸Re-HSAM treated groups were 381 and 267.4 mm³ (p = 0.001 and 0.004), respectively.

CONCLUSIONS

These results show that three-dimensional ultrasound with a high spatial resolution and contrast in soft tissue can become imaging modality in assessing tumor burden and tumor progression in an orthotopic rat model. The longitudinally therapeutic evaluation of ¹⁸⁸Re-HSAM demonstrated dose-dependent tumor growth inhibition with increased dose in the GP7TB orthotopic hepatoma rat model.

Immunological impression cytology of the conjunctival epithelium in patients with thyroid orbitopathy-related dry eye

Thyroid orbitopathy (TO) is an autoimmune disease that is complicated by ocular surface disorders, leading to discomfort. Dry eye is very prevalent in patients with TO. Recent studies on the pathogenesis of dry eye have focused on the inflammatory process, and some supporting evidence has been discovered. Because TO is a disorder of autoimmune origin, we assumed that the association between TO and dry eye is related to inflammation. Inflammation of the ocular surface in TO-related dry eye has not been well studied. In this study, we assessed cellular inflammation of the ocular surface and the cytokine profiles in patients with TO-related dry eye. Conjunctival impression cytology (CIC) was assessed with an immunofluorescent assay. TO-related dry eye was diagnosed by using the Schirmer test, tear break-up time, thyroid function, and clinical signs. CIC was combined with immunological staining of interleukin-1a (IL-1a), IL-1b, and IL- 6. The immunological impression cytology (IC) grade was compared to the clinical activity score of TO. All TO patients with dry eye were positive for IL-1a, IL-1b, and IL-6. However, the normal controls were also positive for IL-1a. A trend was observed between the clinical inflammatory score and immunological IC grade. This study was the first to delineate the immunological IC of TO-related dry eye. Our study aimed to investigate the pathogenesis of dry eye in TO. Our findings suggest that the conjunctival cytokines IL-1a, IL-1b, and IL-6 may play a role. The results of this study will be useful for future studies of additional inflammatory cytokines, and the levels of these cytokines could be used as an outcome to assess the efficacy of treatment, such as anti-cytokine or immunosuppression therapy, in patients with TO-related dry eye or other ocular surface inflammatory disorders.

Econazole induces increases in free intracellular Ca2+ concentrations in human osteosarcoma cells

Econazole is an antifungal drug with different in vitro effects. However, econazole's effect on osteoblast like cells is unknown. In human MG63 osteosarcoma cells, the effect of econazole on intracellular Ca2+ concentrations ([Ca2+]i) was explored by using fura-2. At a concentration of 0.1 μM, econazole started to cause a rise in [Ca2+]i in a concentration-dependent manner. Econazole-induced [Ca2+]i rise was reduced by 74% by removal of extracellular Ca2+. The econazole-induced Ca2+ influx was mediated via a nimodipine-sensitive pathway. In Ca2+ free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca2+ ATPase, caused a [Ca2+]i rise, after which the increasing effect of econazole on [Ca2+]i was abolished. Pretreatment of cells with econazole to deplete Ca2+ stores totally prevented thapsigargin from releasing Ca2+. U73122, an inhibitor of phospholipase C, abolished histamine (an inositol 1,4,5-trisphosphate dependent Ca2+ mobilizer)-induced, but not econazoleinduced, [Ca2+]i rise. Econazole inhibited 76% of thapsigargin-induced store-operated Ca2+ entry. These findings suggest that in MG63 osteosarcoma cells, econazole increases [Ca2+]i by stimulating Ca2+ influx and Ca2+ release from the endoplasmic reticulum via a phospholipase C-independent manner. In contrast, econazole acts as a potent blocker of store-operated Ca2+ entry.

Preparation and characterization of a novel Al(18)F-NOTA-BZA conjugate for melanin-targeted imaging of malignant melanoma

Melanin is an attractive target for the diagnosis and treatment of malignant melanoma. Previous studies have demonstrated the specific binding ability of benzamide moiety to melanin. In this study, we developed a novel (18)F-labeled NOTA-benzamide conjugate, Al(18)F-NOTA-BZA, which can be synthesized in 30min with a radiochemical yield of 20-35% and a radiochemical purity of >95%. Al(18)F-NOTA-BZA is highly hydrophilic (logP=-1.96) and shows good in vitro stability. Intravenous administration of Al(18)F-NOTA-BZA in two melanoma-bearing mouse models revealed highly specific uptake in B16F0 melanotic melanoma (6.67±0.91 and 1.50±0.26%ID/g at 15 and 120min p.i., respectively), but not in A375 amelanotic melanoma (0.87±0.21 and 0.24±0.09%ID/g at 15 and 120min p.i., respectively). The clearance from most normal tissues was fast. A microPET scan of Al(18)F-NOTA-BZA-injected mice also displayed high-contrast tumor images as compared with normal organs. Owing to the favorable in vivo distribution of Al(18)F-NOTA-BZA after intravenous administration, the estimated absorption dose was low in all normal organs and tissues. The melanin-specific binding ability, sustained tumor retention, fast normal tissues clearance and thelow projected human dosimetry supported that Al(18)F-NOTA-BZA is a very promising melanin-specific PET probe for melanin-positive melanoma.

Designing a stronger interface through graded structures in amorphous/nanocrystalline ZrCu/Cu multilayered films

Many multilayered nano-structures appear to fail due to brittle matter along the interfaces. In order to toughen them, in this study, the microstructure and interface strength of multilayered thin films consisting of amorphous ZrCu and nanocrystalline Cu (with sharp or graded interfaces) are examined and analyzed. The interface possesses a gradient nature in terms of composition, nanocrystalline phase size and volume fraction. The bending results extracted from the nano-scaled cantilever bending samples demonstrate that multilayered films with graded interfaces would have a much higher interface bending strength/strain/modulus, and an overall improvement upgrade of more than 50%. The simple graded interface design of multilayered thin films with improved mechanical properties can offer much more promising performance in structural and functional applications for MEMS or optical coating.

Synthesis and characterization of a novel radioiodinated phenylacetamide and its homolog as theranostic agents for malignant melanoma

Melanin is an attractive target for the diagnosis and treatment of malignant melanoma. This study reports the preparation and biological characterizations of N-(2-(diethylamino)ethyl)-2-(3-(123/131)I-iodo-4- hydroxyphenyl)acetamide and N-(2-(diethylamino)ethyl)-3-(3-(123/131)I-iodo-4-hydroxyphenyl)propanamide (123/131)I-IHPA and 123/131I-IHPP) as novel melanin-specific theranostic agents. These two tracers were hydrophilic, exhibited good serum stability and high binding affinity to melanin. In vitro and in vivo studies revealed rapid, high and tenacious uptakes of both 131I-IHPA and 131I-IHPP in melanotic B16F0 cell line and in C57BL/6 mice bearing B16F0 melanoma, but not in amelanonic A375 cell line and tumors. Small-animal SPECT imaging also clearly delineate B16F0 melanoma since 1 h postinjection of 123I-IHPA and 123I-IHPP in tumor-bearing mice. Owing to the favorable biodistribution of 131I-IHPA and 131I-IHPP after intravenous administration, the estimated absorption dose was low in most normal organs and relatively high in melanotic tumor. The melanin-specific binding ability, sustained tumor retention, fast normal tissues clearance and acceptable projected human dosimetry supported that these two tracers are promising theranostic agents for melanin-positive melanoma.

Characteristic Comparison Between 131I-Interferon-α and 131I-Interferon-α-Immunoglobulin-Fc Hybrid Protein in Rats Using Molecular Imaging

BACKGROUND/AIM

Interferon-α (IFN-α) is produced to act locally and transiently with a relatively short circulation half-life in vivo. Hybridization of IFN-α with human immunoglobulin Fc, renamed as IFN-α-Fc, may overcome this limitation. In the present study, (131)I-IFN-α-Fc and (131)I-IFN-α were compared in the aspects of stability, pharmacokinetics, tissue distribution and molecular imaging quality in an animal model.

MATERIALS AND METHODS

Both IFN-α-Fc and IFN-α were labelled with (131)I. Biodistributions and pharmacokinetics of both labelled proteins in Sprague-Dawley rats were assayed. Micro-single-photon emission computed tomography/computed tomography was used to non-invasively monitor the longitudinal distribution of both proteins.

RESULTS

(131)I-IFN-α-Fc was shown to have higher stability than (131)I-IFN-α in whole blood, plasma, kidney, liver and stomach from the biodistribution study. The area under curve analyzed from plasma in the phomacokinetics study was 10-fold higher for (131)I-IFN-α-Fc than for (131)I-IFN-α. At 0-1 h post tail-vein injection, both labelled proteins are mainly accumulated in the kidneys and liver. Notably, (131)I-IFN-α-Fc is degraded more slowly than (131)I-IFN-α.

CONCLUSION

We demonstrated that (131)I-IFN-α-Fc has longer blood circulation time and better biostability than (131)I-IFN-α, suggesting the potential application of the immunoglobulin Fc-conjugated cytokine for long-term treatment of diseases.

Effects of low amplitude pulsed radiofrequency stimulation with different waveform in rats for neuropathic pain

Pulsed-radiofrequency (PRF) electrical stimulation has been widely used for chronic pain treatment. It has been demonstrated with advantages of low temperature over traditional continuous radiofrequency (CRF) lesions with higher amplitude and mono polar electrode to treat pain in clinics (frequency 500 KHz, Pulse duration 20 msec, Amplitude 45 V, Treatment 2 min). We compare the effects of different pulse waveforms and PRF parameters (Pulse duration 25 ms, Treatment duration 5 min, low amplitude of 2.5/1.25 V) with a miniature bi-polar electrode on Dorsal root ganglion (DRG). The pain relief effect due to PRF is evaluated by using Von Frey method for the pain threshold index based on behavior response to mechanical stimulus of various strengths. Experimental results of Von Frey Score show that the sinusoidal group has higher responses than the square wave one. Both fast and secondary expressed proteins of c-fos and pp38 are measured from spinal cord tissue sectioning slides to characterize the pain associated inflammatory responses and their responses due to PRF stimulation.

External beam radiotherapy synergizes ¹⁸⁸Re-liposome against human esophageal cancer xenograft and modulates ¹⁸⁸Re-liposome pharmacokinetics

External beam radiotherapy (EBRT) treats gross tumors and local microscopic diseases. Radionuclide therapy by radioisotopes can eradicate tumors systemically. Rhenium 188 ((188)Re)-liposome, a nanoparticle undergoing clinical trials, emits gamma rays for imaging validation and beta rays for therapy, with biodistribution profiles preferential to tumors. We designed a combinatory treatment and examined its effects on human esophageal cancer xenografts, a malignancy with potential treatment resistance and poor prognosis. Human esophageal cancer cell lines BE-3 (adenocarcinoma) and CE81T/VGH (squamous cell carcinoma) were implanted and compared. The radiochemical purity of (188)Re-liposome exceeded 95%. Molecular imaging by NanoSPECT/CT showed that BE-3, but not CE81T/VGH, xenografts could uptake the (188)Re-liposome. The combination of EBRT and (188)Re-liposome inhibited tumor regrowth greater than each treatment alone, as the tumor growth inhibition rate was 30% with EBRT, 25% with (188)Re-liposome, and 53% with the combination treatment at 21 days postinjection. Combinatory treatment had no additive adverse effects and significant biological toxicities on white blood cell counts, body weight, or liver and renal functions. EBRT significantly enhanced the excretion of (188)Re-liposome into feces and urine. In conclusion, the combination of EBRT with (188)Re-liposome might be a potential treatment modality for esophageal cancer.

Superradiant modes in resonant quasi-periodic double-period quantum wells

This paper firstly proposes the existence of superradiant modes in resonant quasi-periodic double-period quantum wells (QWs), which has not been observed from analyzing the structure factor by traditional methods. Using the gap map method, the reflection spectra under the relevant conditions show that there are dips in the middle and the linewidth grows linearly, despite the dips, as the number of QWs increases, which is a direct demonstration of superradiance. It is also found that the relevant conditions are divided into three regions, each of which has a different width of bandgaps.

Synthesis and evaluation of ¹²³/¹³¹I-Iochlonicotinamide as a novel SPECT probe for malignant melanoma

Malignant melanoma expresses a highly aggressive metastasis. Early diagnosis of malignant melanoma is important for patient survival. Radiolabeled benzamides and nicotinamides have been reported to be attractive candidates for malignant melanoma diagnosis as they bind to melanin, a characteristic substance that displays in malignant melanoma, and show high tumor accumulation and retention. Herein, we designed and synthesized a novel (123/131)I-labeled nicotinamide derivative that specifically binds to melanin. (123/131)I-Iochlonicotinamide was prepared with good radiochemical yield (50-70%, decay corrected) and high specific radioactivity (50-80 GBq/μmol). (131)I-Iochlonicotinamide exhibited good in vitro stability (radiochemical purity >95% after a 24-h incubation) in human serum. High uptake of (123/131)I-Iochlonicotinamide in B16F0 melanoma cells compared to that in A375 amelanotic cells demonstrated its selective binding to melanin. Intravenous administration of (123/131)I-Iochlonicotinamide in a melanoma-bearing mouse model revealed high uptake in melanotic melanoma and high tumor-to-muscle ratio. MicroSPECT scan of (123/131)I-Iochlonicotinamide injected mice also displayed high contrast tumor imaging as compared with normal organs. The radiation-absorbed dose projection for the administration of (131)I-Iochlonicotinamide to human was based on the results of biodistribution study. The effective dose appears to be approximately 0.44 mSv/MBq(-1). The specific binding of (123/131)I-Iochlonicotinamide to melanin along with a prolonged tumor retention and acceptable projected human dosimetry suggest that it may be a promising theranostic agent for treating malignant melanoma.

Preparation and imaging of rhenium-188 labeled human serum albumin microsphere in orthotopic hepatoma rats

OBJECTIVE

The present study relates to a method for preparing 188Re-labeled human serum albumin microspheres (HSAM) by 188Re(I)-tricarbonyl ion(188Re(OH2)3(CO)3)+). This radioactive particle can be subjected to radioembolization for liver tumor.

METHODS

The particle sizes and conformations of HSA microspheres were analyzed by Particle sizes-Malvern mastersizer and Scanning Electron Microscope (SEM). For preparing 188Re(I)-tricarbonyl ion, the 188ReO4- was eluted from a 188W/188Re generator with saline. The radio labeling efficiency was analyzed with high-performance liquid chromatography (HPLC). Amino borane-reduced 188ReO4-was interacted with carbon oxide to form (188Re(OH2)3(CO)3]+). For preparing 188Re-HSA microspheres, the 188Re(I)-tricarbonyl ion was added into a vial with HSA microspheres. The in vitro stability was investigated. The rat was injected with 188Re-HSA microspheres via hepatic artery route. Nano-SPECT/CT Imaging was acquired after injection of 188Re-HSA microspheres.

RESULTS

The shape of HSA microsphere was rough surfaced sphere or oval-shaped. The particle size was distributed between 20 and 35μm. In the RP-HPLC-UV chromatography, the yield of 188Re(I)-tricarbonyl ion was 75-80%. The labeling efficiency of 188Re-HSA microspheres in this method was more than 85%. After incubation, the 188Re(I)-tricarbonyl ion labeled HSA microspheres were found to be stable in vitro in normal saline and rat plasma. The result of Nano-SPECT/CT Imaging quantification analysis indicated that the percentage of injection dose %ID was maintained at 95% ID-88% ID from 2 to 72h after injection with 188Re- HSA microspheres.

CONCLUSIONS

The method of 188Re(I)-tricarbonyl ion labeled HSA microspheres can proceed with high labeling yield. Furthermore, this method provided a convenient method for radio-labeling of HSA microspheres with 188Re as well as a kit for manufacturing.

Evaluation of 188Re-labeled PEGylated nanoliposome as a radionuclide therapeutic agent in an orthotopic glioma-bearing rat model

PURPOSE

In this study, the (188)Re-labeled PEGylated nanoliposome ((188)Re-liposome) was prepared and evaluated as a therapeutic agent for glioma.

MATERIALS AND METHODS

The reporter cell line, F98(luc) was prepared via Lentivector expression kit system and used to set up the orthotopic glioma-bearing rat model for non-invasive bioluminescent imaging. The maximum tolerated dose applicable in Fischer344 rats was explored via body weight monitoring of the rats after single intravenous injection of (188)Re-liposome with varying dosages before the treatment study. The OLINDA/EXM 1.1 software was utilized for estimating the radiation dosimetry. To assess the therapeutic efficacy, tumor-bearing rats were intravenously administered (188)Re-liposome or normal saline followed by monitoring of the tumor growth and animal survival time. In addition, the histopathological examinations of tumors were conducted on the (188)Re-liposome-treated rats.

RESULTS

By using bioluminescent imaging, the well-established reporter cell line (F98(luc)) showed a high relationship between cell number and its bioluminescent intensity (R(2)=0.99) in vitro; furthermore, it could also provide clear tumor imaging for monitoring tumor growth in vivo. The maximum tolerated dose of (188)Re-liposome in Fischer344 rats was estimated to be 333 MBq. According to the dosimetry results, higher equivalent doses were observed in spleen and kidneys while very less were in normal brain, red marrow, and thyroid. For therapeutic efficacy study, the progression of tumor growth in terms of tumor volume and/or tumor weight was significantly slower for the (188)Re-liposome-treated group than the control group (P<0.05). As a result, the lifespan of glioma-bearing rats treated with (188)Re-liposome was prolonged 10.67% compared to the control group.

CONCLUSION

The radiotherapeutic evaluation by dosimetry and survival studies have demonstrated that passive targeting (188)Re-liposome via systemic administration can significantly prolong the lifespan of orthotopic glioma-bearing rats while maintaining reasonable systemic radiation safety. Therefore, (188)Re-liposome could be a potential therapeutic agent for glioblastoma multiforme treatment.

Twin extra-high photoluminescence in resonant double-period quantum wells

Twin extra high photoluminescence (PL) in resonant quasi-periodic double-period quantum wells (DPQWs) for higher-generation orders is demonstrated. In the DPQW, the number of maxima in the maximum values of the PL intensity is two, which is different from other quasi-periodic quantum wells (QWs) and traditional periodic QWs. The maximum PL intensity in a DPQW is also stronger than that in a periodic QW under the anti-Bragg condition and that in a Fibonacci QW. Although the peaks of the squared electric field for the twin PL are both located near the QWs, their field profiles are distinct.

Pharmacokinetics and preliminary safety data of a single oral dose of bosentan, a dual endothelin receptor antagonist, in cats

The objective of this study was to evaluate the pharmacokinetic properties and adverse effect profile of single-dose oral bosentan, a dual endothelin receptor antagonist, in healthy cats. Pharmacokinetic parameters were determined following a single mean ± SD oral dose of 3.2 ± 0.6 mg/kg of bosentan in 6 adult cats. Blood was collected for quantification of bosentan via high-performance liquid chromatography with ultraviolet detection. Blood and urine were evaluated for CBC, plasma biochemical profile, and urinalysis, and repeat physical examinations were performed to evaluate for adverse effects. The mean terminal half-life of bosentan was 20.4 ± 17.2 h. The mean peak plasma concentration was 0.49 ± 0.24 g/mL, and the mean time to maximum plasma concentration was 6.8 ± 8.6 h. The area under the curve was 5.14 ± 3.81 h·μg/mL. Oral bosentan tablets were absorbed in cats, and no clinically important adverse events were noted. Further evaluation of repeat dosing, investigation into the in vivo efficacy of decreasing endothelin-1 concentrations in cats, as well as safety in conjunction with other medications is warranted.

Single dose acute toxicity testing for N,N-bis(2-mercaptoethyl)-N',N' diethylethylenediamine in beagles

N,N-Bis(2-mercaptoethyl)-N',N'-diethylenediamine (BMEDA) is used in the preparation of the (188)Re-BMEDA-liposome as a chelator to deliver rhenium 188 into liposomes. Although the safety of the (188)Re-BMEDA-liposome had been established, the use of BMEDA in preparing the liposome is of interest; however, an assessment of its safety is warranted. In this present work, we report on the acute toxicity study of BMEDA in beagles to identify doses causing no adverse effect and doses causing life-threatening toxicity. In a single dose 14-day systemic toxicity study conducted in beagles, BMEDA was without compound-related adverse effects at doses of up to 2mg/kg in a series of clinical observations and clinical pathology examinations. The results of these studies could aid in choosing doses for repeat-dose studies and in the selection of starting doses for Phase 1 human studies.

Exciton photoluminescence in resonant quasi-periodic Thue-Morse quantum wells

This Letter investigates exciton photoluminescence (PL) in resonant quasi-periodic Thue-Morse quantum wells (QWs). The results show that the PL properties of quasi-periodic Thue-Morse QWs are quite different from those of resonant Fibonacci QWs. The maximum and minimum PL intensities occur under the anti-Bragg and Bragg conditions, respectively. The maxima of the PL intensity gradually decline when the filling factor increases from 0.25 to 0.5. Accordingly, the squared electric field at the QWs decreases as the Thue-Morse QW deviates from the anti-Bragg condition.

Combined therapeutic efficacy of 188Re-liposomes and sorafenib in an experimental colorectal cancer liver metastasis model by intrasplenic injection of C26-luc murine colon cancer cells

Rhenium-188 (¹⁸⁸Re) displays abundant intermediate energy β emission and possesses a physical half-life of 16.9 h. Sorafenib is an orally available multikinase inhibitor that targets Raf kinases and vascular endothelial growth factor receptors (VEGFRs). Sorafenib has demonstrated preclinical and clinical activity against several types of tumors, such as renal cell and colorectal carcinoma. In this study, we investigated the efficacy of radiotherapeutics of ¹⁸⁸Re-liposomes combined with sorafenib in a C26-luc metastatic colorectal liver tumour mouse model. Liver metastases were established by intrasplenic injection of C26-luc murine colon cancer cells. Based on the results of the toxicity assessment, an administration dose of 80% the maximum tolerated dose was selected. ¹⁸⁸Re-liposomes were administered on day 1, when metastases of several hundred micrometers in diameter were observed. In the combination therapy group, 10 mg/kg sorafenib (co-developed and co-marketed by Bayer and Onyx Pharmaceuticals as Nexavar) was administered every other day for 1 week and the survival of mice was assessed. The tumor growth was more significantly inhibited in the ¹⁸⁸Re-liposome plus sorafenib group compared with the ¹⁸⁸Re-liposome alone, sorafenib alone and untreated normal saline groups (P=0.0000). Furthermore, ¹⁸⁸Re-liposomes combined with sorafenib achieved higher survival rates compared with the ¹⁸⁸Re-liposome alone, sorafenib alone and untreated normal saline groups (P=0.0000). These results support the use of combined radio-chemotherapy with ¹⁸⁸Re-liposomes plus sorafenib as a viable treatment option in the adjuvant setting for liver metastases of colorectal cancer.