Non-treated Samples Research Articles

Thermal Conductance of Epoxy/Alumina Interfaces

The interfacial thermal conductance (ITC) between filler and polymer matrix is considered as one of the important factors that limits the thermal conductivity of thermally conductive polymer composites. The effect of two different surface treatments (piranha solution and plasma) on ITC of epoxy/alumina was investigated using Time-domain thermoreflectance method (TDTR). The TDTR results show that compared with non-treated samples, the ITC of samples treated by piranha solution and plasma increased 2.9 times and 3.4 times, respectively. This study provides guidance for improving the thermal conductivity of thermally conductive polymer composites.

Effect of natural green coating materials on the postharvest quality of Prunus salicina Lindl. cv. ‘Shazikongxinli fruit’: A sustainable approach to prevent economic and food loss

The present study was conducted to develop and analyze four different natural materials to explore the green, convenient, and economical storage and fresh-keeping method of the Prunus salicina Lindl. cv. ‘Shazikongxinli’ fruit. Beeswax, grease, resin, and starch were used to prepare different coating materials and applied and analyzed fruit physicochemical parameters, such as fruit decay, weight loss, soluble solids content, titratable acid, ascorbic acid content, reducing sugar content, total phenol, and flavonoid content. The results showed that the four different natural coating preservatives profoundly preserved the freshness quality of Prunus salicina Lindl. cv. ‘Shazikongxinli’ fruit compared to the nontreated samples. In addition, the beeswax and grease-coated fruits showed significantly lower rotting rates (72.87%) and weight loss (4.65%), respectively. Beeswax was also found to maintained soluble solids content (8.50%), titratable acid (0.53%), and ascorbic acid content (3.43 mg/mL) during storage. However, the total phenol content and flavonoid content were significantly lower as 0.71 mg/100 g and 1.57 mg/100 g, respectively, in the beeswax coated fruits compared to control and other treated fruits. This could be one of the protective mechanisms of beeswax coating during storage. Furthermore, the developed green natural preservative method showed excellent results in maintaining the Prunus salicina Lindl. cv. ‘Shazikongxinli’ postharvest quality up to two weeks, providing an alternative green sustainable means of reducing the food and economic losses and possibly replacing the toxic health and environmental effects of using chemical preservatives.

EFFECTS OF HEAT TREATMENT ON SOME CHEMICAL COMPOUND AND MECHANICAL PROPERTIES OF BLACK PINE WOOD

In this study, effects of heat treatment on bending strength, compression strength, chemical compound and solubility of Black pine wood (Pinus nigra J.F.var. seneriana)was examined.For this purpose, Black pine wood samples were kept in temperature of 250°C for 2 hours. Test results of heat-treated Black pine wood and control samples indicated that mechanical characteristics including compression strength and bending strength were affected negatively with heat treatment. Bending strength of heat treated and non-treated test samples were 129 and 76 N.mm-2, respectively. Compression strength of heat treated and non-treated test samples were 53 and 43N.mm-2, resp.In addition, level of extractives, cellulose and hemicellulose decreased while lignin content increased with percentage of 40%. Significant decreases occurred in all chemical solubility values.

Impact of biocontrol microbes on soil microbial diversity in ginger (Zingiber officinale Roscoe).

Bacteria are the most diverse and abundant group of soil organisms that influence plant growth and health. Bacillus and Trichoderma are commonly used as biological control agents (BCA) that directly or indirectly act on soil bacteria. Therefore, it is essential to understand how the applied microbes impact the indigenous microbial community before exploring their activity in the control of soilborne diseases. MiSeq sequencing of the 16S rRNA gene was used to decipher the shift of rhizosphere bacterial community in ginger (Zingiber officinale Roscoe) treated with Bacillus subtilus and Trichoderma harzianum at different concentrations. The dominant phyla in treated and nontreated samples were Proteobacteria, Actinobacteria, Acidobacteria and comprised up to 54.7% of the total sequences. There were significant differences between BCA treated and nontreated samples in the bacteria community. BCA treated plants presented higher bacterial diversity than nontreated and higher dosage of BCA had a larger impact on rhizosphere microbiota, but the 'dose-response relationship' varied in different bacterial groups. Potential biomarkers at genus level were found, such as RB41, Pseudomonas, Nitrospira, Candidatus_Udaeobacter. The combined use of Bacillus subtilus and Trichoderma harzianum could alter bacterial community structure and diversity in rhizosphere soil. BCA-microbes interactions as well as soil microbial ecology should be noticed in plant disease management. © 2021 Society of Chemical Industry.

Electrochemical Behavior of a Stainless Steel Superficially Modified with Nitrogen by Three-dimensional Ion Implantation

Martensitic-grade stainless steels are widely used in diverse industrial and surgical applications, despite their natural tendency to suffer local and uniform corrosion when continuously exposed to aggressive operation conditions. In order to enhance their surface properties, this paper characterized the performance, in saline solutions, of AISI 420 stainless steel, which was surface-modified by three-dimensional ion implantation using electrochemical techniques. The surface of the samples was implanted with ionized nitrogen particles with an energy of 10 keV, varying the implantation time between 30 and 90 minutes. After the surface treatment, the samples were exposed to a NaCl 3% (w/w) aqueous solution for 21 days. Tafel extrapolation, linear polarization resistance, and electrochemical impedance spectroscopy tests were performed, with the purpose of quantifying the effect of the ion implantation technique against electrochemical corrosion. To establish a comparison, the same tests were also performed on non-treated samples. The results indicated an increase in the corrosion potential, polarization resistance, and a decrease in the current density of implanted samples, thus demonstrating that, by delaying corrosive activity, traditional ion implantation offers better protection against electrochemical corrosion in AISI 420 stainless steel samples implanted with nitrogen.

Investigating the effect of organic acids on the survival of Listeria monocytogenes and Escherichia coli O157:H7 in Atlantic salmon stored at 4 ± 1°C

The aim of this study was to investigate the effect of ascorbic, citric and lactic acid (1% and 5%) on the survival of Listeria monocytogenes and Escherichia coli O157:H7 inoculated on fresh Atlantic salmon stored at 4 ± 1°C. In this study, in general, L. monocytogenes and E. coli O157: H7 population in samples treated with organic acids were significantly lower than in non-treated fish samples. The most effective (p < .05), organic acid in reducing L. monocytogenes and E. coli O157:H7 population was 5% lactic acid. The results of this study showed that with increasing organic acid concentration, organic acid treatments exhibited significant (p < .05) antimicrobial effect. As a result, the treatment of salmon fish with organic acids may be an effective application to control L. monocytogenes and E. coli O157: H7 in terms of food safety. Novelty Impact Statement In this study, it has been observed that different types and concentrations of organic acids have different antimicrobial effects. Organic acids have a high potential for use in the food industry, as they are both cheap and easily applicable. Organic acid applications may have potential in reducing the risks in salmon contaminated with L. monocytogenes and E. coli O157: H7, which pose a threat to food safety and human health.

The Effect of Ethanol Treatment on the Quality of a New Table Grape Cultivar It 681-30 Stored at Low Temperature and after a 7-Day Shelf-Life Period at 20 °C: A Molecular Approach.

Despite the fact that many studies have examined the effectiveness of different gaseous postharvest treatments applied at low temperature to maintain table grape quality, the use of ethanol vapor has hardly been investigated. Thus, this work has studied the effectiveness of ethanol vapor-generating sachets in the maintenance of It 681–30 table grape quality, a new cultivar, during storage at low temperature and after the shelf-life period at 20 °C. To this end, various quality assessments have been carried out and the effect of the ethanol treatment on the expression of different genes (phenylpropanoids, transcription factors, PRs, and aquaporins) was determined. The results indicated that the application of ethanol vapor reduced the total decay incidence, weight loss, and the rachis browning index in It 681–30 grapes stored at 0 °C and after the shelf-life period at 20 °C, as compared to non-treated samples. Moreover, the modulation of STS7 and the different PR genes analyzed seems to play a part in the molecular mechanisms activated to cope with fungal attacks during the postharvest of It 681–30 grapes, and particularly during the shelf-life period at 20 °C. Furthermore, the expression of aquaporin transcripts was activated in samples showing higher weight loss. Although further work is needed to elucidate the role of ethanol in table grape quality, the results obtained in this work provide new insight into the transcriptional regulation triggered by ethanol treatment.

Qualitative assessment of compost engendered from municipal solid waste and green waste by indexing method

The present study aims at quantification of the quality of three varieties of composts made from municipal solid waste, green waste and combined waste by critically evaluating their physicochemical attributes, effect on soil fertility and metal pollution risk. Each waste type was treated with effective micro-organisms to compare the compost quality using Quality Control Indices. The effect of microbial consortia on the wastes was prominent resulting in decreased pH levels and increased electrical conductivity. C/N ratio ranged between 14-24 for waste composts without microbial treatment, and 8-11 for microbial treated wastes. The fertility parameter was observed to be more in microbial treated waste composts. Also, heavy metals concentration in waste compost without effective microbial treatment was higher than the types given EM. Based on the fertility and clean indices, the treated and untreated municipal solid waste and combined waste compost belonged to class RU-1 and class D, respectively. Moreover, compost prepared from treated and untreated green waste belonged to classes B and C respectively. In general, the prepared CW and GW composts have medium to high fertilizing potential and are fit for domestic as well as commercial use. However, MSW compost is not fit for agricultural purposes as it didn’t improve soil fertility to a greater extent but can be used as a soil conditioner in limited quantity as it can cause metal toxicity. For this reason, proper segregation of inputs at the start of a composting process is necessary to improve its quality before being put to agricultural use as any unbalanced or unchecked content of mixed waste will affect the overall compost quality.

Fabrication and Characterization of Silk Fibroin-Based Nanofibrous Scaffolds Supplemented with Gelatin for Corneal Tissue Engineering

Tissue engineering is a promising approach to overcome the severe worldwide shortage of healthy donor corneas. In this work, we have developed a silk-gelatin composite scaffold using electrospinning and permeation techniques to achieve the properties comparable to cornea analog. In particular, we present the fabrication and comparative evaluation of the novel gelatin sheets consisting of silk fibroin nanofibers, which are prepared using silk fibroin (SF) (in formic acid) and SF (in aqueous) electrospun scaffolds, for its suitability as corneal stromal analogs. All the fabricated samples were treated with ethanol vapor (T) to physically crosslink the silk nanofibers. Micro/nano-scale features of the fabricated scaffolds were analyzed using scanning electron microscopy micrographs. Fourier transform infrared spectroscopy revealed characteristic peaks of polymeric functional groups and modifications upon ethanol vapor treatment. Transparency of the scaffolds was determined using UV-visible spectra. Among all the fabricated samples, the gelatin-permeated SF (in formic acid; T) scaffold showed the highest level of transparency, i.e., 77.75 ± 2.3%, which is similar to that of the native cornea (∼70%–90% [variable with age group]) with healthy acute vision. Contact angle of the samples was studied to estimate the hydrophilicity of the scaffolds. All the scaffolds except non-treated SF (in aqueous; NT) were found to be significantly stable up to 14 days when incubated in phosphate buffered saline at 37°C. Treated samples showed significantly better stability, both physically and microscopically, in comparison to nontreated samples. Proliferation and viability assays of rabbit corneal fibroblast cells (SIRC) and mouse fibroblast cells (L929 RFP) when cultured on fabricated scaffolds revealed remarkable cellular compatibility with gelatin-permeated SF (in formic acid; T) scaffolds compared to SF (in aqueous; T). Unlike other reports in the existing literature, this work presents the design and development of a nanofibrous silk-gelatin composite that exhibits acceptable transparency, cellular biocompatibility, as well as improved mechanical stability comparable to that of native cornea. Therefore, we anticipate that the fabricated novel scaffold is likely to be a good candidate for corneal tissue construct. Moreover, among the fabricated scaffolds, the outcomes depict gelatin-permeated SF (in formic acid; T) composite scaffold to be a better candidate as a corneal stromal analog that carries properties of both the silk and gelatin, i.e., optimal transparency, better stability, and enhanced cytocompatibility.

Abstract 980: Preclinical evaluation of mps1 inhibition in uterine leiomyosarcoma

Abstract Background: Uterine leiomyosarcoma (Ut-LMS) is the commonest malignant mesenchymal tumor arising from the uterus. It is aggressive and the prognosis is dismal. To-date, no specific oncogenic drivers have been identified. Conventional adjuvant therapy and immunotherapy are ineffective and treatment largely remains surgical. MPS1 kinase is vital in spindle assembly checkpoint which safeguards the faithful segregation of chromosomes. Its inactivation leads to mitotic defects and induces mitotic catastrophe. Compare with normal tissue, MPS1 has shown to be overexpressed in Ut-LMS. Method: The Ut-LMS cell lines SK-UT-1 and SKN were treated with a MPS1 inhibitor. RT-qPCR was performed to analyze mRNA expression levels of Spindle Assembly Checkpoint-related genes. Cells were seeded in 96-well plates and treated with MPS1 inhibitor for 4 days. Sulforhodamine B stain was used to labelled viable cells. IC50 of different cell lines was determined by SRB assay. Cell cycle analysis was done after 2 days treatment by propidium iodide staining. Apoptosis study was done after 3 days treatment by AnnexinV/PI apoptotic assay. Flow cytometry was used to analyze PI assay and AnnexinV/PI apoptotic assay. Immunofluorescence staining of centromere, α-tubulin and DAPI was used to label kinetochore, mitotic spindles and DNA. Cells with chromosome missegregation were counted in treated and non-treated samples. Ut-LMS cell lines SKN was injected subcutaneously in Balb/c nude mice and MPS1 inhibitor was administrated through oral gavage daily, tumor weight was record and tumor size was estimated by caliper. Results: The Spindle Assembly Checkpoint-related genes MPS1, CDC20, MAD2L1, BUB1, BUB1B, and KNL1 were found to be overexpressed. SRB assays had shown that there was growth inhibition of both cell lines in a concentration-dependent manner with IC50 values ranged between 40-65 nM. An increase in aneuploidy cells was demonstrated by PI assay, which suggested that MPS1 inhibitor disrupted cell cycle and induced aneuploidy. The inhibitor also induced apoptosis as demonstrated an increase in AnnexinV+/PI+ cells. Chromosome missegregation was demonstrated in double-thymidine block synchronized anaphase cells with immunofluorescence staining. Micronuclei were also identified in tetraploid cells. In a preliminary in vivo study, MPS1 inhibitor was shown to reduce tumor growth in xenograft models. Conclusion: Our preclinical results indicated that MPS1 inhibitor was an effective treatment in Ut-LMS as a single agent by causing chromosome missegregation, mitotic catastrophe, genomic instability and cell death. Further evaluation of its use in combination with other pharmacological agents is in progress. Citation Format: Ho Shing Wong, Hok Yeung H. Lee, Ka Yu Tse, Tak Wah Mak, Philip PC Ip. Preclinical evaluation of mps1 inhibition in uterine leiomyosarcoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 980.

Comparison of low energy and high energy electron beam treatments on sensory and chemical properties of seeds

Consumption of fresh and minimally processed foods such as seeds as a part of a healthy diet is a trend. Unfortunately, fat-rich seeds are often contaminated with pathogenic microorganisms and face frequent product recalls. Electron beams have been applied as a microbial decontamination measure for decades. Conventionally high energy electron beams (HEEB) are being used, whereas low energy electron beams (LEEB, <300 keV) have only recently been introduced to the food industry and more studies are needed. Electron beam treatment has several advantages over other decontamination technologies. The treatment is non-thermal, chemical-free, water-free, and does not use radioactive substances. The effect of electron beams on the sensory and chemical properties of seeds has not been widely studied. This study assessed LEEB and HEEB treated pumpkin and flax seeds immediately after treatments, and after three months of storage. The seeds’ sensory profiles were altered after both treatments when compared with non-treated samples, with a higher dose leading to a greater level of alteration. However, the sensory profile of LEEB treated seeds was similar to the non-treated seeds whereas HEEB treated seeds differed from both. The storage period of three months further increased the observed differences between the samples. LEEB and HEEB treatments seemed to cause lipid degradation as the content of volatile aldehydes was increased. This effect was more profound in HEEB treated samples. The data presented in this study shows that LEEB as a microbial reduction solution has great potential to preserve the chemical and sensory properties of nutritious seeds.

Low-Temperature Virus vB_EcoM_VR26 Shows Potential in Biocontrol of STEC O26:H11.

Shiga toxin-producing Escherichia coli (STEC) O26:H11 is an emerging foodborne pathogen of growing concern. Since current strategies to control microbial contamination in foodstuffs do not guarantee the elimination of O26:H11, novel approaches are needed. Bacteriophages present an alternative to traditional biocontrol methods used in the food industry. Here, a previously isolated bacteriophage vB_EcoM_VR26 (VR26), adapted to grow at common refrigeration temperatures (4 and 8 °C), has been evaluated for its potential as a biocontrol agent against O26:H11. After 2 h of treatment in broth, VR26 reduced O26:H11 numbers (p < 0.01) by > 2 log10 at 22 °C, and ~3 log10 at 4 °C. No bacterial regrowth was observed after 24 h of treatment at both temperatures. When VR26 was introduced to O26:H11-inoculated lettuce, ~2.0 log10 CFU/piece reduction was observed at 4, 8, and 22 °C. No survivors were detected after 4 and 6 h at 8 and 4 °C, respectively. Although at 22 °C, bacterial regrowth was observed after 6 h of treatment, O26:H11 counts on non-treated samples were >2 log10 CFU/piece higher than on phage-treated ones (p < 0.02). This, and the ability of VR26 to survive over a pH range of 3–11, indicates that VR26 could be used to control STEC O26:H11 in the food industry.

Rituximab Activates NOTCH1 Signaling in CLL Cells and Induces Changes in the Cytokine Repertoire Favoring a Tumor-Protective Microenvironment

IntroductionThe addition of the anti-CD20 monoclonal antibody (mAb) rituximab to chemotherapy improves responses in almost all chronic lymphocytic leukemia (CLL) patients, with the exception of those having NOTCH1 mutations. The reasons for this are largely unknown.NOTCH1 is a cell surface receptor releasing its intracellular domain (NICD) upon activation. The NICD is a transcription factor and NOTCH1 mutations in CLL lead to longer lasting transcription factor activity.We studied the effects of rituximab on NOTCH1 receptor activity and aimed to identify mechanisms of resistance towards chemoimmunotherapy based on NOTCH1 signaling.Material & MethodsFreshly isolated peripheral blood mononuclear cells from CLL patients attending St. Bartholomew's Hospital, London were enriched for CD19 positive cells by negative selection using EDTA free buffer. Cells were treated with mAbs for various time periods. Whole protein lysates were obtained after 15, 30 and 60 min of mAb treatment; RNA was isolated after 150 min. NICD was semi-quantitatively assessed by western blot and NICD target gene expression, such as expression of HES1, was quantified by TaqMan® probe-based quantitative PCR. Global gene expression profiling was done using Affymetrix® Human Gene ST 2.0 Arrays on 3 biological replicates of treated and non-treated samples each deriving from the same patient.ResultsCLL cells freshly isolated from peripheral blood showed low NOTCH1 signaling activity. Following in-vitro treatment of cells with rituximab for 15, 30 or 60 min we observed NOTCH1 receptor activation with NICD release in a time-dependent manner, regardless of NOTCH1 mutation status. We used appropriate controls to distinguish whether NOTCH1 activation was associated with CD20 engagement and/or Fcγ-receptor (FcγR) IIB binding. Trastuzumab was used as an isotype control and led to stronger NOTCH1 activation than F(ab')2 fragments of rituximab, suggesting that NICD release mainly occurs upon engagement of FcγRIIB.In line with this, in-vitro treatment of cells with rituximab was followed by up-regulated expression of NICD target genes such as HES1 . Global gene expression analysis when maximum HES1 gene expression was observed revealed 139 up-regulated and 124 down-regulated probesets in an analysis comparing rituximab treated with non-treated samples (fold-change ≥1.5; p-value ≤0.05) with the majority being non-coding RNAs. Only 28 differentially regulated probesets were actually coding for known genes. Gene set enrichment analysis against the curated genesets of the MSigDB collection (C2) identified 9 enriched genesets (false discovery rate <25%), mainly related to cytokine secretion.The two most up-regulated genes were CCL2 and CCL4 with fold-changes of 6.5 and 3.2, respectively (p<0.001). The gene locus of CCL2 was previously identified as a direct NICD target and CCL2 and CCL4 were both shown to be produced by CLL cells. Numerous studies have linked CCL2 and CCL4 with the recruitment of tumor-protective immune cells such as tumor associated macrophages and T-cell subsets thereby changing the composition of the tumor microenvironment.While wild-type NICD induced only short-lived gene expression changes after transient NOTCH1 activation, mutant NICD elicited more sustained changes. Since NOTCH1 activation following rituximab binding is likely to be temporary, we hypothesise that expression changes of cytokines such as CCL2 and CCL4 last long enough only in NOTCH1 mutant CLL to induce profound changes in the tumor microenvironment.ConclusionIn summary, our data shows for the first time that rituximab binding to CLL cells can activate NOTCH1 signaling and influence the cells' transcriptome. We believe that NOTCH1 induced changes to the cytokine repertoire contribute to the formation of a tumor-protective microenvironment and that the extent of this is dependent on the durability of NICD's transcription factor activity, which is prolonged in NOTCH1 mutant CLL.In ongoing studies we are testing the effects of ofatumumab and obinutuzumab on NOTCH1 signaling and we are using sequential samples taken before and after anti-CD20 mAb infusion to define the extent to which rituximab can influence NOTCH1 signaling in-vivo. We also aim to characterise the cellular composition of the CLL microenvironment with regard to NOTCH1 mutation status and NOTCH1 activity. DisclosuresGribben:Kite: Honoraria; Karyopharm: Honoraria; Acerta: Honoraria; Pharmacyclics: Honoraria; Celgene: Honoraria; TG Therapeutics: Honoraria; Abbvie: Honoraria; Janssen: Honoraria; Genentech/Roche: Honoraria.

Role of a corona field application in the physicochemical properties of stored strawberries

Grey mould disease caused by the fungus Botrytis cinerea Pers is widely distributed on strawberries as the dominant postharvest disease. Therefore, fruits have been treated using a pin-to-plate corona electrical field at a high voltage electric field (HVEF) intensity of 3.61, 4.56, and 5.13 kV·cm&lt;sup&gt;–1&lt;/sup&gt; for 60 minutes. The result revealed that the corona discharge demolished the B. cinerea growth using 20 kV·cm&lt;sup&gt;–1&lt;/sup&gt; for 10 min in the Petri dishes. In addition, the treated strawberries at 4.56 kV·cm&lt;sup&gt;–1&lt;/sup&gt; had an average infection rate of 23.33% compared with non-treated samples rate of 45.33%. The HVEF-treated samples showed significantly lower mass losses. The analysis of variance showed that the HVEF did not significantly affect the total soluble solids content, pH, titratable acidity, and softness; however, the lower acidity affected the Botrytis cinerea growth. No significant differences were observed among the mean values in the colour change parameters and colour difference for 4.56 kV·cm&lt;sup&gt;–1&lt;/sup&gt; compared with the control, while the lightness was significantly higher. The result show that the corona electrical field was able to demolish the B. cinerea growth, and an electric field intensity at 4.56 kV·cm&lt;sup&gt;–1&lt;/sup&gt; was found to extend the strawberries' cold storage and to lead to a lower mass loss.

Antimicrobial activity of MccJ25(G12Y) against gram-negative foodborne pathogens in vitro and in food models

The use of bacteriocins is a promising alternative to improve food security through the biocontrol of food pathogens and spoilage microorganisms. Gram-negative produced microcin J25(G12Y), known as (MccJ25(G12Y)) is a variant of the well-studied and characterized antimicrobial peptide, microcin J25 (MccJ25). In the present work, we explored the activity of this microcin against Gram-negative bacteria linked to foodborne diseases.We evaluated the in vitro antimicrobial activity of MccJ25(G12Y) in solid medium against a collection of pathogenic and food-altering strains and studied its activity and stability in meat and dairy food systems. We show that MccJ25(G12Y) exhibited the same in vitro antimicrobial spectrum as its parental microcin (MccJ25) against different Gram-negative foodborne pathogens and spoilage strains. We highlight that low concentrations of MccJ25(G12Y) between 0.45 and 29.4 μM were able to inhibit a substantial number of pathogens, including Salmonella, Escherichia, Shigella and Enterobacter genus. We also demonstrate the antimicrobial effectiveness of the peptide against Escherichia coli O157:H7 NCTC 12900, Enterobacter cloacae CECT 194, and Salmonella enterica CECT 4396 in fish and beef burgers and yogurt. MccJ25(G12Y) was added or not to food matrices inoculated with the foodborne pathogens at 105 CFU/g or mL. Afterward, food products were stored at 4 °C and selective media for the specific enumeration were used to determine the antimicrobial susceptibility of each pathogen to MccJ25(G12Y). The viability of the three pathogens was significantly reduced in the different food biological environments. In yogurt, the peptide decreased E. coli numbers on day 5 by about 4 log 10 CFU/mL as compared to non-treated samples. For S. enterica and E. cloacae no viable cells were detected at the end of the treatment. Adding MccJ25(G12Y) to fish burgers decreased E. cloacae numbers during storage 2 log10 CFU/g on the first day, reaching a difference of about 5 log 10 CFU/g after 10 days compared to non-treated control. Finally, the peptide decreased E. coli O157:H7 numbers on the beef burgers samples during storage on day 10 by about 3 log 10 CFU/g as compared to non-treated samples. The stability analysis demonstrated that MccJ25(G12Y) is capable of remaining active in these food matrices for a considerable time during the storage at refrigeration temperatures. These results reinforce the studies on the potential applicability of this microcin as a biopreservative in the food industry.

Lactic fermentation of grain sorghum: effect of variety and pretreatment on the production of lactic acid and biomass.

Grain sorghum is a viable feedstock for lactic acid fermentation; however, tannins contained in some varieties affect the efficiency of hydrolysis and fermentation. This work objective was to assess the effect of pre-treatment of grain sorghum on the production of lactic acid and biomass after fermentation. Sorghum varieties with low, medium, and high tannins were pretreated, enzymatically hydrolyzed, and fermented with Lactobacillus casei. The pre-treatments consisted of cooking the grains in lime, cooking in plain water, and no treatment (control). Pretreated sorghum flours were hydrolyzed using thermostable α-amylase from Bacillus licheniformis and amyloglucosidase from Aspergillus niger. Lime pre-treatment showed a significant improvement in protein content, digestibility, and lactic acid production after fermentation, in relation to the non-treated samples. Although differences were not significant for low and medium tannins, lime treatment increase lactic acid production for the cooked-in-lime high-tannin sorghum in relation to the control. For this sorghum/treatment combination, the lactic acid production was 138 g/L, with a volumetric productivity of 1.57 g/L·h and 85/100 g yield based on initial starch, which is equivalent to 69 g of lactic acid per 100 g of sorghum d.b.

Z-scores for comparative analyses of spermatogonial numbers throughout human development

To normalize age-dependent effects on standardized measures of spermatogonial quantity such as the number of spermatogonia per tubular cross-section (S/T) or fertility index. Published quantitative histologic data on human spermatogonial numbers were used to create Z-scores for reference means and tested on archived testicular tissue samples. Retrospective cohort study. The sample cohort comprised testicular samples from 24 boys with cancer diagnosis and 10 with Klinefelter syndrome, as part of the fertility preservation programs NORDFERTIL and Androprotect, as well as archived histologic samples from 35 prepubertal boys with acute lymphoblastic leukemia and 20 testicular biobank samples. None. Z-score values for S/T and fertility index on the basis of morphology and germ cell-specific markers (MAGEA4 and/or DDX4) were calculated, and the impact of cancer therapy exposure and genetic disorders on Z-score values was evaluated. The Z-scores for S/T values in the nontreated samples (-2.08 ± 2.20, n = 28) and samples treated with nonalkylating agents (-1.90 ± 2.60, n = 25) were comparable within ±3 standard deviations of the reference mean value but differed significantly from samples exposed to alkylating agents (-12.14 ± 9.20, n = 22) and from patients with Klinefelter syndrome (-11.56 ± 4.89, n = 8). The Z-scores for S/T were correlated with increasing cumulative exposure to alkylating agents (r = -0.7020). The Z-score values for S/T allow for the quantification of genetic and cancer treatment-related effects on testicular tissue stored for fertility preservation, facilitating their use for patient counseling.

Fluorescence lifetime imaging microscopy and time-resolved anisotropy of nanomaterial-induced changes to red blood cell membranes

With the use of engineered nano-materials (ENM) becoming more prevalent, it is essential to determine potential human health impacts. Specifically, the effects on biological lipid membranes will be important for determining molecular events that may contribute to both toxicity and suitable biomedical applications. To better understand the mechanisms of ENM-induced hemolysis and membrane permeability, fluorescence lifetime imaging microscopy (FLIM) was performed on human red blood cells (RBC) exposed to titanium dioxide ENM, zinc oxide ENM, or micron-sized crystalline silica. In the FLIM images, changes in the intensity-weighted fluorescence lifetime of the lipophilic fluorescence probe Di-4-ANEPPDHQ were used to identify localized changes to membrane. Time-resolved fluorescence anisotropy and FLIM of RBC treated with methyl-ß-cyclodextrin was performed to aid in interpreting how changes to membrane order influence changes in the fluorescence lifetime of the probe. Treatment of RBC with methyl-ß-cyclodextrin caused an increase in the wobble-in-a-cone angle and shorter fluorescence lifetimes of di-4-ANEPPDHQ. Treatment of RBC with titanium dioxide caused a significant increase in fluorescence lifetime compared to non-treated samples, indicating increased membrane order. Crystalline silica also increased the fluorescence lifetime compared to control levels. In contrast, zinc oxide decreased the fluorescence lifetime, representing decreased membrane order. However, treatment with soluble zinc sulfate resulted in no significant change in fluorescence lifetime, indicating that the decrease in order of the RBC membranes caused by zinc oxide ENM was not due to zinc ions formed during potential dissolution of the nanoparticles. These results give insight into mechanisms for how these three materials might disrupt RBC membranes and membranes of other cells. The results also provide evidence for a direct correlation between the size, interaction-available surface area of the nano-material and cell membrane disruption.

CHANGES IN GROSS CALORIFIC VALUE OF THERMALLY TREATED SCOTS PINE (PINUS SYLVESTRIS L.) AND SESSILE OAK (QUERCUS PETRAEA L.) WOOD AND THEIR EXPLANATION USING FTIR SPECTROSCOPY

Scots pine (Pinus sylvestris L.) and Sessile oak (Quercus petraea L.) wood were thermally treated in an oven at the temperatures of 160°C, and 200°C under atmospheric pressure in the presence of air for 3 and 9 hrs. The mass loss and gross calorific value were determined. Non-treated wood samples achieved a gross calorific value of 22 193 J.g-1 for pine wood and 19 277 J.g-1 for oak wood. Whereas the calorific value of pine wood with increasing severity of treatment decreased, in the case of oak it increased. The mass loss increased with increasing treatment severity by both wood species. Mentioned differences in pine and oak wood behaviour using ATR-FTIR spectroscopy were explained. In the case of pine wood with increasing temperature and time of exposure a decrease of resin acids was observed. This may be contributed to decrease in GCV. In the case of oak wood, mainly at temperature of 200°C the degradation of hemicelluloses was observed that results in relative increasing in the lignin content with followed increase in the GCV.

Developing near infrared spectroscopy models for predicting chemistry and responses to stress in Pinus radiata (D. Don)

Incorporating chemical traits in breeding requires the estimation of quantitative genetic parameters, especially the levels of additive genetic variation. This requires large numbers of samples from pedigreed populations. Conventional wet chemistry procedures for chemotyping are slow, expensive and not a practical option. This study focuses on the chemical variation in Pinus radiata, where the near infrared (NIR) spectral properties of the needles, bark and roots before and after exposure to methyl jasmonate (MJ) and artificial bark stripping (strip) treatments were investigated as an alternative approach. The aim was to test the capability of NIR spectroscopy to (i) discriminate samples exposed to MJ and strip assessed 7, 14, 21 and 28 days after treatment from untreated samples, and (ii) quantitatively predict individual chemical compounds in the three plant parts. Using principal components analysis (PCA) on the spectral data, we differentiated between treated and untreated samples for the individual plant parts. Based on partial least squares–discriminant analysis (PLS-DA) models, the best discrimination of treated from non-treated samples with the smallest root mean square error cross-validation (RMSECV) and highest coefficient of determination (r2) was achieved in the fresh needles (r2 = 0.81, RMSECV= 0.24) and fresh inner bark (r2 = 0.79, RMSECV = 0.25) for MJ-treated samples 14 days and 21 days after treatment, respectively. Using partial least squares regression, models for individual compounds gave high (r2), residual predictive deviation (RPD), lab to NIR error (PRL) or range error ratio (RER) for fructose (r2 = 0.84, RPD = 1.5, PRL = 0.71, RER = 7.25) and glucose (r2 = 0.83, RPD = 1.9, PRL = 1.14, RER = 8.50) and several diterpenoids. This provides an optimistic outlook for the use of NIR spectroscopy-based models for the larger-scale prediction of the P. radiata chemistry needed for quantitative genetic studies.