Resistances to benzalkonium chloride of bacteria dried with food elements on stainless steel surface

To confirm the importance of washing food sediments from the surface of food-related environments, we examined resistances against benzalkonium chloride of pathogenic bacterial (Escherichia coli O26, Pseudomonas aeruginosa and Staphylococcus aureus) cells dried and adhered on stainless steel dishes with milk, beef gravy or tuna gravy. Suspensions (0.1 ml) of these bacteria (8-9 log cfu/ml) were put on a 5 cm ? stainless steel dish and dried at room temperature (20-24 °C) for 90 min in a bio-clean bench with ventilation. Though these bacteria suspended with distilled water decreased 30-40 fold during the drying period, milk and the gravies protected the bacteria. Without the food elements, the adhered E. coli and Stap. aureus were decreased from 6 to<2 log cfu/dish by 0.5 mg/ml benzalkonium chloride (BKC) for 10 min treatment. Although Ps. aeruginosa showed resistance to BKC, the adhered cells were inactivated by 2.0 mg/ml BKC. However, the bactericidal effect disappeared by the food elements, particularly with milk, even at 1.0 and/or 2.0 mg/ml BKC levels. The protective efficiency of milk on bacteria disappeared if washed with water.     

Simple preprocessing method for multi-determination of 235 pesticide residues in cooked ingredients of foods by GC/MS and LC/MS/MS

A simple preprocessing method was developed for multiresidue determination of pesticides in processed agricultural products. Residues were extracted from homogenized samples with acetonitrile in a glass centrifuge tube, followed by salting-out and partitioning with n-hexane. Co-extractives were removed by means of mini-column clean up. Analysis was performed by GC/MS and LC/MS/MS. The prepared sample solutions were examined for matrix effects. Matrix effects had both positive and negative effects on quantitative value. Calibration was achieved by preparing matrix-matched calibration standards to counteract the matrix effects. Of the 235 pesticides spiked at 0.05 or 0.10 microg/g (Method GC), 0.025 or 0.05 microg/g (Method LC) into 8 foods (garlic paste, diced green sweet pepper, green peas paste, celery paste, sweet potato paste, dried adzuki beans, boiled bamboo shoots, tomato paste), recoveries of 214 pesticides were between 50 and 100% and the coefficient of variation was below 20%. This method is useful as a multi-residue analysis method for screening of pesticides in foods.     

Effect of sesamin on mitochondrial and peroxisomal β-oxidation of arachidonic and eicosapentaenoic acids in rat liver

The effects of dietary sesamin on the hepatic metabolism of arachidonic (AA) and eicosapentaenoic (EPA) acids, were investigated with respect to their β-oxidation and secretion as triacylglycerol (TG). For 2 wk, rats were fed three types of dietary oils: (i) corn oil (control) group; (ii) FPA group: FPA ethyl esters/rapeseed oil=2∶3; (iii) AA group: AA ethyl esters/palm oil/perilla oil=2∶2∶1, with or without 0.5% (w/w) of sesamin. Dietary sesamin significantly increased the activities of hepatic mitochondrial and peroxisomal fatty acid oxidation enzymes (mitochondrial carnitine acyltransferase I, acyl-CoA dehydrogenase, and peroxisomal acyl-CoA oxidase). Dietary FPA increased mitochondrial carnitine acyltransferase I and peroxisomal acyl-CoA oxidase. Dietary AA, however, had an effect on peroxisomal acyl-CoA oxidase only. In whole liver and the TG fraction, EPA and AA concentrations were significantly increased by dietary EPA and AA, respectively, and were decreased by dietary sesamin. In hepatic mitochondria and peroxisomes, EPA concentration was increased by dietary EPA, but AA was not changed by dietary AA. The addition of dietary sesamin to the EPA-supplemented diet significantly decreased the EPA concentration compared to concentrations found with consumption of dietary EPA alone. These results suggest that sesamin increased β-oxidation enzyme activities and reduced hepatic EPA and AA concentrations by degradation. The stimulating effect of sesamin on β-oxidation, however, was more significant in the EPA group than in the AA group. Hepatic AA concentration was altered by the joint effect of sesamin through esterification into TG and the stimulation of β-oxidation.     

Immunotherapy for the Treatment of Squamous Cell Carcinoma: Potential Benefits and Challenges

Melanoma and nonmelanoma skin cancers (NMSCs) are recognized as among the most common neoplasms, mostly in white people, with an increasing incidence rate. Among the NMSCs, squamous cell carcinoma (SCC) is the most prevalent malignancy known to affect people with a fair complexion who are exposed to extreme ultraviolet radiation (UVR), have a hereditary predisposition, or are immunosuppressed. There are several extrinsic and intrinsic determinants that contribute to the pathophysiology of the SCC. The therapeutic modalities depend on the SCC stages, from actinic keratosis to late-stage multiple metastases. Standard treatments include surgical excision, radiotherapy, and chemotherapy. As SCC represents a favorable tumor microenvironment with high tumor mutational burden, infiltration of immune cells, and expression of immune checkpoints, the SCC tumors are highly responsive to immunotherapies. Until now, there are three checkpoint inhibitors, cemiplimab, pembrolizumab, and nivolumab, that are approved for the treatment of advanced, recurrent, or metastatic SCC patients in the United States. Immunotherapy possesses significant therapeutic benefits for patients with metastatic or locally advanced tumors not eligible for surgery or radiotherapy to avoid the potential toxicity caused by the chemotherapies. Despite the high tolerability and efficiency, the existence of some challenges has been revealed such as, resistance to immunotherapy, less availability of the biomarkers, and difficulty in appropriate patient selection. This review aims to accumulate evidence regarding the genetic alterations related to SCC, the factors that contribute to the potential benefits of immunotherapy, and the challenges to follow this treatment regime.     

Trajectories of fluid particles in a periodic water wave

We compute trajectories of fluid particles in a water wave that propagates with a constant shape at a constant speed. The Stokes drift, which asserts that fluid particles are pushed forward by a wave, is proved using a new method. Numerical examples with various gravity and surface tension coefficients are presented.     

Mechanical and scratch behaviors of polyrotaxane-modified poly(methyl methacrylate)

The mechanical and scratch behaviors of polyrotaxane (PR) modified poly(methyl methacrylate) (PMMA) were investigated. PR is a necklace-like supramolecule with rings threaded onto a linear backbone chain that is capped by bulky end groups. Cyclodextrin (CD) serves as the ring structure and can be functionalized to induce specific interactions with the hosting polymer matrix. To systematically investigate the effect of CD functionalization on the mechanical properties of PMMA, PR with polycaprolactone (PCL) grafted chains on CD, and PR with methacrylate functional groups at the terminal of the PCL grafted chains on CD were chosen for this study. Tensile and compressive true stress–strain tests, ASTM scratch test, and coefficient of friction measurements were conducted to fundamentally understand how PR influences the mechanical and scratch behaviors of PMMA. Additionally, dielectric relaxation spectroscopy and dynamic mechanical analysis were conducted to explore how PR influences the relaxation dynamics of PMMA. The above findings suggest that the methacrylate functional group on PR induces favorable molecular interactions with PMMA matrix, leading to enhanced molecular cooperativity during deformation, which in turn improves tensile and compressive properties and achieves greatly improved scratch resistance.     

Crystallographic and Microstructural Studies of Lath Martensitic Steel During Tensile Deformation

Significant crystallographic refinement was observed in the as-quenched lath martensitic steel during tensile deformation up to a strain of 20 pct. Crystallographic investigation by electron backscattering diffraction analysis coupled with the use of crystal plasticity model confirmed that the activation behavior of slip systems is inhomogeneous even within each martensite block. In particular, the activation behavior of slip systems is initially affected by the initial crystal orientation; however, the effect becomes negligible with increasing deformation. In addition, slip systems parallel to the lath plane are preferentially activated during elongation. Our results indicate that the nonuniform crystal rotation within individual blocks is induced not only by grain interaction phenomena but also by the anisotropic activity of slip systems. These are key factor that determines the grain refinement behavior in the as-quenched lath martensitic steel during deformation.     

IL-7 induces proliferation, variable cytokine-producing ability and IL-2 responsiveness in naive CD4+ T-cells from human cord blood

It is a basic assumption of the breakage-and-reunion theory that the majority of open chromatid breaks seen at metaphase are the residue of unrejoined primary breaks that have neither restituted nor rejoined illegitimately to form exchange aberrations. If Chinese hamster chromosomes with BrdU sister-chromatid differentiation are irradiated, and chromatid aberrations scored from G2 cells, some 15-20% of open breaks show a colour-jump at the point of discontinuity, indicating a two-lesion intrachange origin. Since we see complete forms of several intrachanges whose incomplete forms will also look like breaks, but devoid of a colour-jump, it appears that a substantial proportion of observed breaks are intrachange derived. Experiments to date show that the colour-jump proportion is constant, irrespective of radiation dose, radiation quality, BrdU concentration and hamster cell origin. It is the same for the very low "spontaneous' breaks found in control samples. Restriction endonucleases (RE) can be introduced into cells by various poration methods, and are highly efficient at producing all types of aberrations. This is taken as strong evidence that DNA dsb are significant lesions triggering aberrations. One might anticipate, therefore, that observed breaks will be predominantly unrejoined dsb, and the proportion of colour-jump break correspondingly low. We tested this supposition using three RE; Alu 1, a blunt-end cutter, Sau3A 1, a cohesive-end cutter, both with a short life-time in vivo, and Mbo 1, an isoschizomer of Sau3A 1, which has a long cutting life-time in vivo. Although there were differences in absolute yields of breaks, and of relative frequencies of aberration types recovered, the proportion of colour-jump breaks was as high as that in a parallel X-ray experiment, and fell well within the range encountered in all our previous experiments. It is difficult to reconcile this universal constancy of colour-jump breaks with the expectations of breakage-and-reunion theory, where the occurrence of two-break events must be a treatment variable. Rather, our results suggest that most open breaks are secondary, resulting from a regular intrachange processing mechanism.     

Characterization of a photocatalytic reaction in a continuous‐flow recirculation reactor system

A continuous‐flow recirculation mode, generally called a recycle mode, is known to be practically meaningless except when the reactant is separated from the product at the reactor exit or when the reaction is autocatalytic, because when simply circulating a small amount of the fluid containing a reactant, the reactant concentration in this mode is lowered due to mixing of the fluid at the reactor entrance, leading to a decrease in the conversion at the reactor exit. This mode may, however, be meaningful in photocatalytic reactions with very large film‐diffusional resistance. To indicate the validity of this estimation, therefore, characteristics of a continuous‐flow recirculation reactor have been investigated both theoretically and experimentally. As a result, it is found that by increasing the circulation flow rate the conversion and productivity in this reactor is higher than that in a continuous‐flow reactor because the film‐diffusional resistance is remarkably reduced. Copyright © 2006 Society of Chemical Industry     

Effect of ultrafiltration during cardiopulmonary bypass for pediatric cardiac surgery

The effect of ultrafiltration during cardiopulmonary bypass (CPB) was evaluated for correcting ventricular septal defects with associated pulmonary hypertension in patients less than 18 months old. Interleukin (IL)-6 and IL-8 concentrations in the blood, ultrafiltrate, and urine were measured. The blood IL-6 concentration increased to 128.4+/-20.2 pg/ml by the end of surgery, which is lower than the concentration seen in adult patients (273.1+/-48.2 pg/ml, p < 0.02). The blood IL-8 concentration was not significantly different than that of adults. The total amounts of excreted IL-6 in the ultrafiltrate and urine during CPB were 11.5+/-0.32 pg/kg and 0.32+/-0.07 pg/kg, respectively (p < 0.05). The total amounts of excreted IL-8 in the ultrafiltrate and urine were 4.64+/-0.69 pg/kg and 1.92+/-0.56 pg/kg, respectively (p < 0.05). No differences were seen in these values for excretion between children and adults. We conclude that ultrafiltration during CPB in pediatric patients is more effective in removing proinflammatory cytokines than in adults and more effective than renal filtration alone.