Analysis of metribuzin and its metabolites in livestock products and seafoods by liquid chromatography-tandem mass spectrometry

A method for simultaneous determination of metribuzin (MET) and three metribuzin metabolites in livestock products and seafoods by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. MET and its metabolites were extracted from a sample with acetonitrile, followed by InertSepC18 and BondElut SAX cartridge cleanup. The LC separation was performed on a C18 column using 0.01 mol/L ammonium formate-acetonitrile-methanol (70 :21 : 9) as the mobile phase and MS detection with both positive and negative ion electrospray ionization. The mean recoveries from 10 livestock products and seafoods were generally >60%, and the relative standard deviations were <20%     

Self-Folding Graphene-Based Interface for Brain-Like Modular 3D Tissue (Adv. Funct. Mater. 37/2023)

Electrophysiology of 3D neuronal cultures is of rapidly growing importance for revealing cellular communications associated with neurodevelopment and neurological diseases in their brain-like 3D environment. Despite that the brain also exhibits an inherent modular architecture that is essential for cortical processing, it remains challenging to interface a modular network consisting of multiple 3D neuronal tissues. Here, a self-folding graphene-based electrode array is proposed that enables to reconstruct modular 3D neuronal tissue and investigate firing dynamics among moduli. A graphene-sandwiched parylene-C film self-folds into a cylindrical structure within which living cells can be encapsulated. Culture of encapsulated cells inside the folded graphene enables to spontaneously construct 3D cell aggregates and ensure firm contact between the graphene surface and encapsulated cells. As the inner graphene surface can be utilized as an electrode, the reliable cell–electrode contact allows for long-term electrical recording from multiple 3D aggregates. Additionally, the modular network consisting of multiple 3D aggregates exhibits richer firing patterns than a conventional homogenous 2D network, which demonstrates that the approach enables measurements of firing dynamics in complex 3D neuronal networks. The deformable graphene electrode will be a powerful platform for investigating complex cellular communications in brain-like 3D cultures.     

Status report of the JAERI on-line isotope separator

A mass separator has been connected on line to the 20 MV tandem accelerator at JAERI/Tokai. Using a thermal ion source, decay spectroscopic studies have been carried out for neutron-deficient isotopes in the mass 120–130 region. A study with collinear laser spectroscopy has begun recently. The present paper describes the status of the mass separator facility together with some experimental results.     

Clinical results of combination chemotherapy with cisplatin, vinblastine and bleomycin (pvb) for advanced testicular cancer: evaluation of risk criteria

Between 1982 and 1991, 24 patients with advanced testicular germ cell tumor were treated by combination chemotherapy with cisplatin, vinblastine and bleomycin (PVB). Based on short-term efficacy of the PVB regimen and long-term prognosis in our patients, we evaluated 4 risk criteria proposed by Indiana University, National Cancer Institute (NCI), Memorial Sloan-Kettering Cancer Center (MSKCC) and European Organization for Research and Treatment of Cancer (EORTC). Clinical staging were IIA in 8 patients, IIB in 8, IIIA in 1, IIIB in 5 and IIIC in 2. Metastases included retroperitoneal lymph node in 20 cases (> 5 cm in 10), lung in 6, bone and liver in each 1. Complete response (CR) was obtained in 12 (50%) patients and partial response (PR) in 9 (38%). According to the stage and metastatic site, CR was achieved in 75%, 38% and 38%of the stage IIA, IIB and III tumors, respectively, and in 60% and 50% of retroperitoneal and pulmonary metastases, respectively. However, neither CR nor PR was recognized for live and bone metastases. Prognosis was assessed with a mean followup period of 88.5 months. Although all 12 patients with CR were alive, 4 of the 9 with PR and all patients on whom the drug was ineffective died of cancer. Accuracy in predicting prognosis was 82%, 75%, 74%, and 63% using the MSKCC, Indiana, NCI and EORTC risk criteria, respectively.     

Advanced imaging of carcinoma of the mandibular gingiva

To ascertain whether complete cerebral ischemia-reperfusion activate L-Arg: NO pathway in canine brain, we anestherized nine adult dogs with ketamine and fentayle and randomly divided into two groups. Four dogs were nonischemic control group. Five dogs were complete cerebral ischemia-reperfusion group, they underwent a 18-minute cardiac arrest, and were resusciatation by standard CPR, supported by intensive care for 8 hours. At the end of each experiment, the parietal cortex was assayed for content of Nitrite and NADPH-positive neurons. Compared with the control group, the contents of Nitrite and NADPH-positive neurons of coxtex in complete cerebral ischemia-reperfusion group increased significantly (P < 0.01). The results suggest that complete cerebral ischemia-reperfusion activate the L-Arg: NO pathway in canine brain, and NO may play an important role in cerebral ischemia-reperfusion injury.     

Cooperative ion-transfer of copper(II)-1,10-phenanthroline-trifluoroacetylacetone complex across a water/1,2-dichloroethane interface

The cooperative ion-transfer, the facilitated ion-transfer of metal ion with several kinds of ligands, has been studied by a potential-scan cyclic voltammetry and a current-scan polarography at the water/1,2-dichloroethane (DCE) interface using a system which involves copper(II), 1,10-phenanthroline (phen), and 1,1,1-trifluoroacetylacetone (HTAA). Although under the condition of [Cu²⁺] > [phen] in the aqueous phase no wave appears, a new wave has been observed by dissolving HTAA in the organic phase. This wave shows quasi-reversible characteristics and the reversibility increases with an increase in [HTAA]. From the analysis of the voltammetric peak ratio, it has been concluded that the cooperative ion-transfer follows the slow formation of Cu(phen)TAA⁺ at the interface and that the species transferred is also Cu(phen)TAA⁺. Furthermore, at [HTAA] > 1.0 × 10⁻³ M, a second anodic wave begins to appear at a higher potential than the first wave, without any corresponding cathodic wave, and this ion-transfer may be followed by very irreversible chemical reactions including interfacial adsorption. Comparing the results of cyclic voltammography and polarography, some interesting phenomena have been also pointed out and mechanisms of the quasi-reversible cooperative ion-transfer have been elucidated in detail.     

Study of phase separation in blends of silk fibroin and sodium alginate in solution and in solid state

Silk fibroin (SF) and sodium alginate (SA) are natural polymers with many applications as biomaterials. It is possible to make blends with them in order to improve their properties. Those blends are partially miscible; therefore, understanding the mechanism and phase equilibrium of this system is important to better understand the interaction between these natural polymers. This work analyzed the mechanism of phase separation of SF and SA blends with different composition in solution and in the solid state (as membranes) using small angle light scattering with a He-Ne laser. Polymer interaction and conformation were investigated by Fourier-Transform Infrared Spectroscopy with Attenuated Total Reflectance (FTIR-ATR) and X-Ray Diffraction (XRD), and membrane morphology was analyzed by Scanning Electron Microscopy (SEM). SEM images showed interpenetrated globules in the matrix. Light scattering profile for blends in solution and in the solid state showed a peak of intensity suggesting that phase separation occurs by spinodal decomposition.     

Twitter-aided decision making: a review of recent developments

Twitter is one of the largest online platforms where people exchange information. In the first few years since its emergence, researchers have been exploring ways to use Twitter data in various decision making scenarios, and have shown promising results. In this review, we examine 28 newer papers published in last five years (since 2016) that continued to advance Twitter-aided decision making. The application scenarios we cover include product sales prediction, stock selection, crime prevention, epidemic tracking, and traffic monitoring. We first discuss the findings presented in these papers, that is how much decision making performance has been improved with the help of Twitter data. Then we offer a methodological analysis that considers four aspects of methods used in these papers, including problem formulation, solution, Twitter feature, and information transformation. This methodological analysis aims to enable researchers and decision makers to see the applicability of Twitter-aided methods in different application domains or platforms.

     

NIR reflectance spectroscopic analysis of the FA composition in sesame (<Emphasis Type="Italic">Sesamum indicum</Emphasis> L.) seeds

The feasibility of using NIR reflectance spectroscopy to estimate the FA composition of sesame seed (Sesamum indicum L.) samples from the National Institute of Crop Science of Japan and from Myanmar was examined. Multiple linear-regression analyses of NIR sepctral data and chemical data for whole seeds were carried out to develop calibration equations for predicting the proportion of each of the four major FA in sesame seeds from the total FA composition. The SE of prediction (SEP) was 0.616% for palmitic acid, 0.348% for stearic acid, 1.051% for oleic acid, and 0.826% for linoleic acid. This NIR method provides a simple, rapid, and nondestructive means of estimating the FA composition of sesame seeds for breeding selection, regardless of the color of the sesame seed coats. However, the proportions of palmitic and stearic acids could not be reliably measured because their SEP were almost as great as the SD of their concentrations in the set of prediction samples. The relationship between NIR spectral patterns and the FA composition of sesame seeds also was examined. The correlation coefficient calculated for the standardized second-derivative NIR spectral readings at 1708 nm and the percentages of linoleic acid was −0.830. A rough estimate of the proportion of linoleic acid in the total FA composition of sesame seeds could be obtained even with single sesame seeds, except for those with a black coat, based on NIR spectral pattern analysis using the wavelength assignments of linoleic acid.