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Polyhydroxybutyrate (PHB) is a bio-based, biodegradable and biocompatible plastic that has the potential to replace petroleum-based plastics. Lignocellulosic biomass is a promising feedstock for industrial fermentation to produce bioproducts such as polyhydroxybutyrate (PHB). However, the pretreatment processes of lignocellulosic biomass lead to the generation of toxic byproducts, such as furfural, 5-HMF, vanillin, and acetate, which affect microbial growth and productivity. In this study, to reduce furfural toxicity during PHB production from lignocellulosic hydrolysates, we genetically engineered Cupriavidus necator NCIMB 11599, by inserting the nicotine amide salvage pathway genes pncB and nadE to increase the NAD(P)H pool. We found that the expression of pncB was the most effective in improving tolerance to inhibitors, cell growth, PHB production and sugar consumption rate. In addition, the engineered strain harboring pncB showed higher PHB production using lignocellulosic hydrolysates than the wild-type strain. Therefore, the application of NAD salvage pathway genes improves the tolerance of Cupriavidus necator to lignocellulosic-derived inhibitors and should be used to optimize PHB production.

89Zr is an emerging radionuclide with promising application in nuclear medicine for the non-invasive diagnosis of various cancers with PET imaging. This paper would discuss optimization efforts in the production of 89Zr carried out at Accelerator Radioisotope Development Team, Korea Atomic Energy Research Institute. Optimized conditions reveal high production yields of 89Zr ~ 37 ± 1.4 MBq/µA using 89Y(p,n)89Zr, ~ 12.7 MeV of proton, and 35 µA using yttrium coin target with indigenously constructed 30 MeV Cyclotron (RFT-30). Besides, the production optimization, quality control, and biological behavior of [89Zr]Zr-oxalate, chloride and, DFO demonstrated promising results.

A novel zeolite imidazole framework-8 (ZIF-8) composite was synthesized as an accelerator, and its effects on the physical properties of epoxies were examined. To prepare the new accelerator, fullerene was oxidized with 3-chloroperoxybenzoic acid under reflux for 5 h in toluene. The dried powder (fullerene oxide, C60(O)n) was reacted with AgNO3 solution to obtain the fullerene oxide-Ag nanoparticle composite C60(O)n–Ag, which was further reacted with ZIF-8 to afford the composite C60(O)n–Ag/ZIF-8. The composite was analyzed by X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, and energy dispersive spectrometry. After the accelerator was added to the epoxy composites, the thermal curing properties were studied using differential scanning calorimetry. The composition was cured at a high temperature for subsequent physical tests, including dynamic mechanical analysis (DMA), transmission electron microscopy, and single overlap adhesion testing. The DMA results showed that the addition of C60(O)n–Ag/ZIF-8 to epoxy compositions resulted in an increase in tan δ by 11.5 °C, compared to that of the composition containing 2-methylimidazole (2MI) accelerator (147.2 °C). Furthermore, the single-lap shear strength test showed that the C60(O)n–Ag/ZIF-8 composition was 9.8% stronger (18.4 MPa) than that with 2MI (16.6 MPa).

Accumulation of triphenylphosphonium (TPP) is normally observed in the mitochondria from the extracellular spaces due to the high difference in plasma membrane potential of the mitochondria. In the cancer cells, the mitochondrial membrane potential gap is higher as compared to that of normal cells resulting in elevated uptake of TPP. Silica nanoparticles (SNPs) being widely developed and used for biomedical applications, in this study, we tried to modify the surface of SNPs with varying amounts of TPP to verify their possible application as a positron emission tomography (PET) agent. The studies confirmed that the high level of TPP loading on the surface of SNPs possess higher positive charge (+ 31.5 mV). Owing to this behavior of plasma membrane potential of cancerous cells the uptake of positively charged SNPs was much higher in tumor cells than that of normal cells which was confirmed by PET imaging.

The conducting polymer polypyrrole thin film was galvanostatically polymerized on stainless steel substrate for the supercapacitor electrode. The electrochemical stability of the electrode was monitored each 30 days of aging up to 90 days. The FTIR analysis showed an increase in intensity of the absorption peaks, especially high growth of the carbonyl peaks after 90 days of aging. The electrochemical capacitance degradation of the electrode was studied using cyclic voltammetric and galvanostatic charge/discharge analysis in 1 M Na2SO4 electrolyte, which showed ~ 53% of fading in the initial specific capacitance value after 90 days. Further, the electrochemical degradation of polypyrrole electrodes was analyzed in detail using electrochemical impedance spectroscopy. The analysis showed a large increase in the internal resistance and low-power deliverability of the electrode with respect to aging as the main reasons for the degradation of specific capacitance of the polypyrrole electrode.

In biological applications of nanoparticles, the control of physicochemical properties such as size, shape, and surface charge enables the improvement of their ability for cancer target. In addition, it can be tracked by labeling in these nanoparticles with medical radionuclides for detection of cancer. Here, we report novel chelator-free direct-labeling of hierarchical hematite nanoclusters with 89Zr (89Zr-IONCs) through hydrothermal reaction to develop biocompatible radiolabeled nanoparticle which is effective for tracking cancer cells. Characterization of 89Zr-IONCs revealed that the zirconium ions were tightly bound inside hematite crystals with intervals of glutamic acid absorbed on their surfaces having spindle shape with a mean width of 180 nm and length of 80 nm. This method showed promising radiolabeling yield and labeling stability in biological environments which was ≥ 99%. Their high colloidal stability in serum was considerably maintained for the span of a week by the formation of protein corona with the hematite nanoclusters. For the result of biological evaluations, cytotoxicity assay provides evidence of the high biocompatibility of the product. The elevated in vitro cellular uptake of 89Zr-IONCs for the CT-26 and A549 cells was observed. Furthermore, we found that the spindle shape of 89Zr-IONCs was more effective for cell internalization compared with round shape due to the extended interfacial surface area with a cell membrane when their endocytosis is started. Our one-pot synthesized 89Zr-incorporated hematite nanoclusters show the promising approach for a simple and highly stable chelator-free radiolabeling system, which exploits the non-toxic potential carrier to target cancer cells.

Biomimetic nanoparticles (NPs) have been actively studied for their biological compatibility due to its distinguished abilities viz. long-term circulation, low toxicity, ease for surface modification, and its ability to avoid phagocytosis of NPs by macrophages. Coating the NPs with a variety of cell membranes bearing the immune control proteins increases drug efficacy while complementing the intrinsic advantages of the NPs. In this study, efforts were made to introduce oxophilic radiometal 89Zr with hollow mesoporous silica nanospheres (HMSNs) having abundant silanol groups and were bioengineered with red blood cell membrane (Rm) having cluster of differentiation 47 (CD47) protein to evaluate its long-term in vivo behavior. We were successful in demonstrating the increased in vivo stability of synthesized Rm-camouflaged, 89Zr-labelled HMSNs with the markedly reduced 89Zr release. Rm camouflaged 89Zr-HMSNs effectively accumulated in the tumor by avoiding phagocytosis of macrophages. In addition, re-injecting the Rm isolated using the blood of the same animal helped to overcome the immune barrier. This novel strategy can be applied extensively to identify the long-term in vivo behavior of nano-drugs while enhancing their biocompatibility.

In recent years, concurrent chemoradiotherapy (CCRT) has become a standard treatment modality for patients with locally advanced esophageal cancer. On the other hand, there is no international consensus regarding an accurate definition of the clinical target volume (CTV). This study evaluated the clinical outcomes in patients with locally advanced esophageal cancer treated definitively with either (ENI) elective nodal irradiation or (IFI) involved-field irradiation. Retrospective analysis of the treatment results for patients with locally advanced esophageal cancer between 2001.5 and 2013.5 was carried out. The eligible patients had T2-4N0-2M0 biopsy-proven squamous cell carcinoma (SCC) of the esophagus and were treated with a curative aim. Patients treated with surgery or radiotherapy alone were excluded. The gross tumor volume (GTV) was delineated based on the FDG-PET CT scans. Patients treated with ENI received radiotherapy on the supraclavicular or celiac area as the clinical target volume (CTV). For IFI planning, CTV is defined as a 3-cm superoinferior margin and a 1-cm lateral margin from the GTV. The 3-year progression-free survival, overall survival and patterns of the failures were analyzed. A total of 99 patients who completed CCRT were eligible for the analysis. Of the patients, 50 patients had ENI and 49 patients had IFI. The age, gender and staging were similar in both groups. The median follow-up was 21 months. Both groups showed a similar overall survival (p = 0.293). On the other hand, although not statistically significant, the IFI group showed a tendency for lower 3-year progression-free survival rates, particularly the non-surgery group (25 vs. 46 %, p = 0.075). The cumulative failure rates were significantly lower in the ENI group than in the IFI group. (35 vs. 56 %, p = 0.04). Definitive CCRT with ENI did not improve the survival and disease control for patients with esophageal SCC. The omission of ENI was associated with a higher failure rate, but it did not affect the survival time. PET-CT-guided involved-field irradiation is a reasonable option for most locally advanced thoracic esophageal cancer but needs caution for patients who will not undergo surgery.

We designed a 68Ga labeled Fe3O4 nano-biocomposite for dual applications as diagnostic imaging agent in positron emission tomography (PET)/magnetic resonance imaging (MRI). The nano-biocomposites (68GaNHFCNP) were fabricated via surface modified iron oxide nanoparticles and NOTA as bi-functional chelating agent with 68Ga isotopes from 68Ge/68Ga generator. The structure and morphological properties of nano-biocomposite was characterized by XRD, TEM and IR analysis. 68GaNHFCNPs exhibits very low cytotoxicity and high cellular uptake upon SK-BR-3 and CT-26 cell lines. The advantages of high biocompatibility, magnetism and cell uptake make this composite promising as a potential probe of PET/MRI for effective detection of cancer.

Thioflavin-T (ThT) is a benzothiazole dye that exhibits enhanced fluorescence upon binding to beta-amyloid (Aβ) plaques and is commonly used in the diagnosis of Alzheimer’s disease (AD). In this study, the ThT analogs were designed and synthesized, and screening was conducted for the detection of Aβ 40 fibrils in vitro. Among these compounds, 2-(2′-methoxy-4′-methylaminophenyl)benzoxazole (2) meets two critical requirements for an imaging agent: high its higher fluorescent responsiveness and stronger binding affinity than those of ThT. This compound showed the highest binding affinity with a dissociation constant of 3.27 ± 0.29 μM, and selectively stained Aβ aggregated in SHSY5Y neuroblastoma cells. This finding demonstrates the compound’s potential use as a brain-imaging agent for AD studies.

We retrospectively evaluated the relationship between the response of lung lesions and distant progression-free survival (DPFS) after radiosurgery in patients with brain metastases. A total of 47 consecutive patients were treated with radiosurgery for brain metastases. Distant progression was defined as a new enhancing intracranial tumor or leptomeningeal enhancement noted on follow-up magnetic resonance imaging. Progression of lung lesions was defined as follows: (1) a 20% increase in the summed diameter of the target lesions; (2) an absolute increase of 5 mm when the summed diameter was very small; or (3) detection of new lesions in the lung. Distant progression after radiosurgery was observed for twenty-one (44.7%) patients; we observed development of new distant metastases in nine patients, development of leptomeningeal seeding in eight patients, and combined failure of distant progression and local control failure in four patients. Forty-two (89.4%) patients had lung lesions at the time of radiosurgery, and progression of their lung lesions during the post-radiosurgery follow-up period was observed for 18 (38.3%) of these. The median DPFS was 7.00 months (95% CI, 6.153-7.847). Actuarial DPFS 3, 6, and 12 months after radiosurgery was 81.5, 61.3, and 36.7%, respectively. In multivariate analysis, only the criterion progression of lung lesions reached statistical and independent significance (P = 0.021, OR = 3.372, 95% CI, 1.200-9.480). The response of lung lesions after radiosurgery is likely to be a good predictor of DPFS after radiosurgery in patients with brain metastases.

In the NEtwork MObility (NEMO) environment, mobile networks can form a nested structure. In nested mobile networks that use the NEMO Basic Support (NBS) protocol, pinball routing problems occur because packets are routed to all the home agents of the mobile routers using nested tunneling. In addition, the nodes in the same mobile networks can communicate with each other regardless of Internet connectivity. However, the nodes in some mobile networks that are based on NBS cannot communicate when the network is disconnected from the Internet. In this paper, we propose a route optimization scheme to solve these problems. We introduce a new IPv6 routing header named “destination-information header” (DH), which uses DH instead of routing header type 2 to optimize the route in the nested mobile network. The proposed scheme shows at least 30% better performance than ROTIO and similar performance improvement as DBU in inter-route optimization. With respect to intra-route optimization, the proposed scheme always uses the optimal routing path. In addition, the handover mechanism in ROAD+ outperforms existing schemes and is less sensitive to network size than other existing schemes.

The exact mechanism of rheumatoid arthritis (RA) is unclear, but a combination of genetic, environmental and hormonal factors is thought to be involved. This study examined the progressive arthritic reaction of murine type II collagen-induced arthritis (CIA), a representative animal model of RA. Arthritic reactions, including inflammation and bone erosion were examined using an objective non-invasive method. Two scoring systems were used to evaluate changes in cutaneous inflammation and bone erosion during RA progression. The severity of inflammation was evaluated by visual scoring of erythema and edema, while the degree of bone erosion was quantified by macroradiographical erosion analysis of specific bones. A significant difference was observed in both visual (P = 0.0001, n = 7) and radiographic (P < 0.0001, n = 7) examinations for the RA group as compared to the control. The relationship between inflammatory change and erosive change in bone showed a significant positive correlation, r = 0.9550 (P < 0.0001, n = 7). The overall rate of asymmetry was 25.23% in both fore- and hindpaws. The results generated from these experiments show that murine CIA is a promising model for elucidating the mechanism of RA. In addition, the results of this study may be used for monitoring RA progression as well as screening therapy efficacy in the joint pathology.

Background We performed dosimetric comparisons between proton beam therapy and intensity modulated radiotherapy (IMRT) of intracranial germ cell tumors (ICGCTs) arising in various locations of the brain. Materials IMRT, passively scattered proton therapy (PSPT), and spot scanning proton therapy (SSPT) plans were performed for four different target volumes: the whole ventricle (WV), pineal gland (PG), suprasellar (SS), and basal ganglia (BG). Five consecutive clinical cases were selected from the patients treated between 2011 and 2014 for each target volume. Total 20 cases from the 17 patients were included in the analyses with three overlap cases which were used in plan comparison both for the whole ventricle and boost targets. The conformity index, homogeneity index, gradient index, plan quality index (PQI), and doses applied to the normal substructures of the brain were calculated for each treatment plan. Results The PQI was significantly superior for PSPT and SSPT than IMRT for ICGCTs in all locations (median; WV: 2.89 and 2.37 vs 4.06, PG: 3.38 and 2.70 vs 4.39, SS: 3.92 and 2.49 vs 4.46, BG: 3.01 and 2.49 vs 4.45). PSPT and SSPT significantly reduced the mean dose, and the 10 and 15 Gy dose volumes applied to the normal brain compared with IMRT (p ≤ 0.05). PSPT and SSPT saved significantly greater volumes of the temporal lobes and hippocampi (p

The Korea Atomic Energy Research Institute (KAERI) has launched a decommissioning program of the uranium conversion plant. The sludge waste, which was generated during the operation of the plant and stored in the lagoon, was characterized for the development of the treatment process. The physical properties were measured and chemical compositions and radiological properties analyzed. The main compounds of the sludge were ammonium nitrate, sodium nitrate, calcium nitrate, and calcium carbonate. All heavy radioactive elements such as uranium, thorium and 226Ra were precipitated and deposited at the bottom, and were not dissolved in the concentrated nitrate solution. A possible flow-scheme for processing is presented.