Synthesis, In Vitro Testing, and Biodistribution of Surfactant-Free Radioactive Nanoparticles for Cancer Treatment

New forms of cancer treatment, which are effective, have simple manufacturing processes, and easily transportable, are of the utmost necessity. In this work, a methodology for the synthesis of radioactive Gold-198 nanoparticles without the use of surfactants was described. The nuclear activated Gold-198 foils were transformed into H198AuCl4 by dissolution using aqua regia, following a set of steps in a specially designed leak-tight setup. Gold-198 nanoparticles were synthesized using a citrate reduction stabilized with PEG. In addition, TEM results for the non-radioactive product presented an average size of 11.0 nm. The DLS and results for the radioactive 198AuNPs presented an average size of 8.7 nm. Moreover, the DLS results for the PEG-198AuNPs presented a 32.6 nm average size. Cell line tests showed no cytotoxic effect in any period and the concentrations were evaluated. Furthermore, in vivo testing showed a high biological uptake in the tumor and a cancer growth arrest.

Utility of Bioluminescent Homogeneous Nucleotide Detection Assays in Measuring Activities of Nucleotide-Sugar Dependent Glycosyltransferases and Studying Their Inhibitors

Traditional glycosyltransferase (GT) activity assays are not easily configured for rapid detection nor for high throughput screening because they rely on radioactive product isolation, the use of heterogeneous immunoassays or mass spectrometry. In a typical glycosyltransferase biochemical reaction, two products are generated, a glycosylated product and a nucleotide released from the sugar donor substrate. Therefore, an assay that detects the nucleotide could be universal to monitor the activity of diverse glycosyltransferases in vitro. Here we describe three homogeneous and bioluminescent glycosyltransferase activity assays based on UDP, GDP, CMP, and UMP detection. Each of these assays are performed in a one-step detection that relies on converting the nucleotide product to ATP, then to bioluminescence using firefly luciferase. These assays are highly sensitive, robust and resistant to chemical interference. Various applications of these assays are presented, including studies on the specificity of sugar transfer by diverse GTs and the characterization of acceptor substrate-dependent and independent nucleotide-sugar hydrolysis. Furthermore, their utility in screening for specific GT inhibitors and the study of their mode of action are described. We believe that the broad utility of these nucleotide assays will enable the investigation of a large number of GTs and may have a significant impact on diverse areas of Glycobiology research.

Introduction of Interim Storage of SNF in INET

There are three research reactors of different type in Institute of Nuclear and New Energy Technology of Tsinghua University (INET), they are Swimming Pool Shielding Reactor (SPSR), 5MW Nuclear Heating Reactor (NHR-5) and 10MW High Temperature Gas Cooled Reactor (HTR-10). The interim storage facilities for Spent Nuclear Fuel (SNF) are applied in these reactors except NHR-5, the SPSR adopts the wet storage for its SNFs, HTR-10 accepts the dry storage due to the ceramic structure of its SNFs. The practical storage conditions including SNFs features, space distribution, SNFs transportation, shielding measures and the safety analysis results including radioactive activity, shielding effect, the total amount of radioactive product leakage to environment are demonstrated in this paper.

Partial and total thermal neutron capture cross sections for non-destructive assay and transmutation monitoring of 99Tc

SummaryAccurate partial gamma-ray production cross sections were determined for the prompt and radioactive product decay gamma rays following cold neutron capture in

No alpha-lactalbumin-like activity detected in a low molecular mass protein fraction of rat epididymal extract

The same low M(r) protein fraction of epididymal luminal fluid as that studied previously by Hamilton in 1981 was assayed for alpha-lactalbumin (alpha-lac) activity with bovine milk galactosyltransferase (GalTase) as the enzyme source and bovine serum albumin (BSA) to make the total protein concentrations of all the samples in each assay constant. No alpha-lac activity could be detected in this fraction. When glucose was used as an acceptor, radioactivity passing through the ion exchange column used to retain the remaining UDP-galactose did increase with the amount of the proteins of the low M(r) fraction, but this increase was observed not only for samples with an acceptor but also for samples without. The increased radioactive product co-migrated in high-voltage electrophoresis with galactose, not lactose. When GlcNAc was used as an acceptor, the situation was the same, and the increased radioactive product co-migrated with galactose, not LacNAc. No inhibition of bovine milk GalTase activity by the low M(r) proteins was observed. Addition of protein, either BSA or the low M(r) fraction of epididymal luminal fluid, to assay medium that contained no proteins other than GalTase enhanced the GalTase activity both in forming lactose in the presence of glucose and also LacNAc in the presence of GlcNAc. It appears that the earlier reports of alpha-lac-like activity in epididymal fluids and extracts may have been due to the presence of enzymes liberating free galactose from UDP-galactose and/or a stimulatory non-specific effect of the protein in the solutions on the lactose synthesis activity of the GalTase.

Comparative Detoxification of Chlorsulfuron in Leaf Disks and Cell Cultures of Two Perennial Weeds

Phytotoxicity of chlorsulfuron {2-chloro-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino] carbonyl] benzenesulfonamide} in cell cultures of Canada thistle [Cirsium arvense(L.) Scop. # CIRAR] was approximately 30-fold greater than in leafy spurge (Euphorbia esulaL. # EPHES) cultures. Differences in chlorsulfuron phytotoxicity in these two species were attributed to large differences in cellular metabolism of the herbicide. Leafy spurge cells metabolized all of the applied14C-chlorsulfuron within 72 h of treatment, while Canada thistle metabolized less than 2%. Acid hydrolysis of the metabolic products isolated from leaf disks and cell cultures of leafy spurge yielded a radioactive product that cochromatographed with a 2-chlorobenzenesulfonamide standard. Therefore, metabolic transformation occurred on the heterocyclic portion of the molecule. A major metabolite was further characterized as 2-chloro-N-[[4-(hydroxymethyl)-6-methoxy-1,3,5-triazin-2-yl]aminocarbonyl]-benzenesulfonamide by cochromatography with the authentic standard.