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Author(s):  
Shyam L. Kandel ◽  
Rubaiya Jesmin ◽  
Brian M. Mack ◽  
Rajtilak Majumdar ◽  
Matthew K. Gilbert ◽  
...  

Aspergillus flavus is an opportunistic pathogen of oilseed crops such as maize, peanut, cottonseed, and tree nuts and produces carcinogenic secondary metabolites known as aflatoxins during seed colonization. Aflatoxin contamination not only reduces the value of the produce but also is a health hazard to humans and animals. Previously, we observed inhibition of A. flavus aflatoxin biosynthesis upon exposure to the marine bacterium, Vibrio gazogenes (Vg). In this study, we used RNA sequencing to examine the transcriptional profiles of A. flavus treated with both live and heat-inactivated dead Vg and control samples. Fungal biomass, total accumulated aflatoxins, and expression profiles of genes constituting secondary metabolite biosynthetic gene clusters were determined at 24, 30, and 40 h after treatment. Statistically significant reductions in total aflatoxins were detected in Vg-treated samples as compared to control samples at 40 h. But no statistical difference in fungal biomass was observed upon these treatments. The Vg treatments were most effective on aflatoxin biosynthesis as was reflected in significant downregulation of majority of the genes in the aflatoxin gene cluster including the aflatoxin pathway regulator gene, aflR. Along with aflatoxin genes, we also observed significant downregulation in some other secondary metabolite gene clusters including cyclopiazonic acid and aflavarin, suggesting that the treatment may inhibit other secondary metabolites as well. Finally, a weighted gene correlation network analysis identified an upregulation of ten genes that were most strongly associated with Vg-dependent aflatoxin inhibition and provide a novel start-point in understanding the mechanisms that result in this phenomenon.


2022 ◽  
Author(s):  
Mehran Dehghanian ◽  
Ghafour Yarahmadi ◽  
Reyhaneh Sadat Sandoghsaz ◽  
Farimah Shamsi ◽  
Ali Khodadadian ◽  
...  

Abstract Objective: Endometriosis is a female reproductive system disease in which endometrial tissue are found in other women organs. Various factors are effective in the development of endometriosis and due to the interaction of genetics and environmental factors, this disease is a multifactorial disease. MAPK/ERK and PI3K/Akt/mTOR pathways are activated by growth factors and steroid hormones and known as two important pathways involved in the processes of growth, proliferation and survival of endometriosis cells. Raps, monomeric GTPase of Ras family, are able to activate these pathways independently of Ras. The goal of our study was to evaluated the expression level of Rap1GAP and Epac1 gene, as two important RapGAPs (GTPase-activating proteins) and RapGEFs (guanine nucleotide exchange factors) respectively, in endometriosis tissues and normal endometrium tissues.Materials and Methods: In this study, 15 samples of women without signs of endometriosis were taken as control samples, 15 ectopic and 15 eutopic samples were taken from women with endometriosis using laparoscopic surgery. The expression of Epac1 and Rap1GAP genes was investigated by Real-time PCR technique and results were analysis by One-Way ANOVA test.Results: Epac1 upregulated significantly in ectopic tissues compared to eutopic and control tissues (Their P-value were <0.0001). Rap1GAP expression was lower in ectopic tissues compared to control samples (P-value was 0.003) and eutopic tissues (P-value was 0.001).Conclusion: Based on these results, it may be concluded that changes in the expression of the Rap1GAP and Epca1 genes may play role in the pathways involved in the pathogenesis, displacement, and migration of endometriosis cells.


2022 ◽  
Author(s):  
Samuel Katz ◽  
Haining Chen ◽  
David Fields ◽  
Erin Beirne ◽  
Phoebe Keyes ◽  
...  

Photoproducts can be formed rapidly in the initial phase of a marine oil spill. However, their toxicity is not well understood. In this study, oil was irradiated, chemically characterized, and tested for toxicity in three copepod species (A. tonsa, T. longicornis, C.finmarchicus). Irradiation led to a depletion of polycyclic aromatic hydrocarbons (PAHs) and n-alkanes in oil residues, along with an enrichment in aromatic and aliphatic oil photoproducts. Target lipid model-based calculations of PAH toxic units (TU-PAH) predicted that PAH toxicities were lower in water accommodated fractions (WAFs) of irradiated oil residues (“irradiated WAFs”) than in WAFs of dark-control samples (“dark WAFs”). In contrast, biomimetic extraction (BE) measurements showed increased bioaccumulation potential of irradiated WAFs compared to dark WAFs, mainly driven by photoproducts present in irradiated oil. In line with the BE results, copepod mortality increased in response to irradiated WAFs compared to dark WAFs. Low copepod toxicities were observed for WAFs produced with photooxidized oil slicks collected during the Deepwater Horizon oil spill. The results of this study suggest that while oil photoproducts have the potential to be a significant source of copepod toxicity, the water solubility of these products might mitigate their toxicity at sea.


2022 ◽  
Author(s):  
Yoo-Jin Ha ◽  
Jisoo Kim ◽  
Seungseok Kang ◽  
Junhan Kim ◽  
Se-Young Jo ◽  
...  

Abstract The rapid advances in sequencing and analysis technologies have enabled the accurate detection of diverse forms of genomic variants, including germline, somatic, and mosaic mutations. However, unlike for the former two mutations, the best practices for mosaic variant calling still remain chaotic due to the technical and conceptual difficulties faced in evaluation. Here, we present our benchmark of nine feasible strategies for mosaic variant detection based on a systematically designed reference standard that mimics mosaic samples, with 390,153 control positive and 35,208,888 negative single-nucleotide variants and insertion–deletion mutations. We identified the condition-dependent strengths and weaknesses of the current strategies, instead of a single winner, regarding variant allele frequencies, variant sharing, and the usage of control samples. Moreover, feature-level investigation directs the way for immediate to prolonged improvements in mosaic variant calling. Our results will guide researchers in selecting suitable calling algorithms and suggest future strategies for developers.


Polymers ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 208
Author(s):  
Hongli Li ◽  
Yan Feng ◽  
Peng Zhang ◽  
Mingwei Yuan ◽  
Minglong Yuan

The effect of novel antimicrobial peptides (AMPs) and antimicrobial peptide microspheres (AMS) on the physicochemical and microbial quality of Tricholoma matsutake wild edible mushrooms was investigated. In the experiments, 1.0 g/L, 0.5 g/L of AMS, and 1.0 g/L AMPs were used as preservatives. Mushrooms coated with 1.0 g/L and 0.5 g/L of AMS as a preservative had better physicochemical and sensory qualities than did mushrooms coated with 1.0 g/L of AMPs. In the experiment, 1.0 g/L of blank microspheres without cathelicidin-BF-30 (PLGA-1.0) and distilled water was used as the control. Samples with these two treatments had minimal changes in texture, weight loss, total bacteria count, and sensory attributes. Research results suggests that the use of AMS can maintain the quality of Tricholoma matsutake wild edible mushrooms and could extend the postharvest life to 20 d.


2022 ◽  
Vol 12 ◽  
Author(s):  
Liangcai Xu ◽  
Bo Peng ◽  
Yuxiang He ◽  
Yujun Cui ◽  
Qinghua Hu ◽  
...  

Purpose: To investigate and characterize the putative Elizabethkingia anophelis contaminant isolated from throat and anal swab samples of patients from three fever epidemic clusters, which were not COVID-19 related, in Shenzhen, China, during COVID-19 pandemic.Methods: Bacteria were cultured from throat (n = 28) and anal (n = 3) swab samples from 28 fever adolescent patients. The isolated bacterial strains were identified using matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF/MS) and the VITEK2 automated identification system. Nucleic acids were extracted from the patient samples (n = 31), unopened virus collection kits from the same manufacturer as the patient samples (n = 35, blank samples) and from unopened throat swab collection kits of two other manufacturers (n = 22, control samples). Metagenomic sequencing and quantitative real-time PCR (qPCR) detection were performed. Blood serum collected from patients (n = 13) was assessed for the presence of antibodies to E. anophelis. The genomic characteristics, antibiotic susceptibility, and heat resistance of E. anophelis isolates (n = 31) were analyzed.Results: The isolates were identified by MALDI-TOF/MS and VITEK2 as Elizabethkingia meningoseptica. DNA sequence analysis confirmed isolates to be E. anophelis. The patients’ samples and blank samples were positive for E. anophelis. Control samples were negative for E. anophelis. The sera from a sub-sample of 13 patients were antibody-negative for isolated E. anophelis. Most of the isolates were highly homologous and carried multiple β-lactamase genes (blaB, blaGOB, and blaCME). The isolates displayed resistance to nitrofurans, penicillins, and most β-lactam drugs. The bacteria survived heating at 56°C for 30 min.Conclusion: The unopened commercial virus collection kits from the same manufacturer as those used to swab patients were contaminated with E. anophelis. Patients were not infected with E. anophelis and the causative agent for the fevers remains unidentified. The relevant authorities were swiftly notified of this discovery and subsequent collection kits were not contaminated. DNA sequence-based techniques are the definitive method for Elizabethkingia species identification. The E. anophelis isolates were multidrug-resistant, with partial heat resistance, making them difficult to eradicate from contaminated surfaces. Such resistance indicates that more attention should be paid to disinfection protocols, especially in hospitals, to avoid outbreaks of E. anophelis infection.


2021 ◽  
Vol 4 (4) ◽  
pp. 239-248
Author(s):  
Mehmet Fatih Şahan ◽  
Fatih Ali Öncel ◽  
İsmail Ünsal

This study investigated the effect of fiber ratio on the impact behavior of polypropylene fiber reinforced concrete cube and beam samples. Plain concrete mixtures for control samples and polypropylene fiber-reinforced concrete mixtures with fiber ratios of %0.22, %0.44, and %0.66 by volume were prepared. An instrumented drop-weight impact system was used for the dynamic tests. Static compression tests, three-point bending tests, and impact tests were performed on beam samples (with the dimension of 100×100×500 mm). Static compression and impact tests were performed on cube samples (with the size of 100 mm). It was observed that the fracture properties of polypropylene fiber reinforced concrete for both cube and beam samples were better than the control samples under impact. The crack width in the beams under the impact decreased with the increase in polypropylene fiber ratio. The cube and beam concrete samples reinforced with polypropylene fibers absorbed the impact energy better than the control samples.


Viruses ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 61
Author(s):  
Emanuele Montomoli ◽  
Giovanni Apolone ◽  
Alessandro Manenti ◽  
Mattia Boeri ◽  
Paola Suatoni ◽  
...  

The massive emergence of COVID-19 cases in the first phase of pandemic within an extremely short period of time suggest that an undetected earlier circulation of SARS-CoV-2 might have occurred. Given the importance of this evidence, an independent evaluation was recommended by the World Health Organization (WHO) to test a subset of samples selected on the level of positivity in ELISA assays (positive, low positive, negative) detected in our previous study of prepandemic samples collected in Italy. SARS-CoV-2 antibodies were blindly retested by two independent centers in 29 blood samples collected in the prepandemic period in Italy, 29 samples collected one year before and 11 COVID-19 control samples. The methodologies used included IgG-RBD/IgM-RBD ELISA assays, a qualitative micro-neutralization CPE-based assay, a multiplex IgG protein array, an ELISA IgM kit (Wantai), and a plaque-reduction neutralization test. The results suggest the presence of SARS-CoV-2 antibodies in some samples collected in the prepandemic period, with the oldest samples found to be positive for IgM by both laboratories collected on 10 October 2019 (Lombardy), 11 November 2019 (Lombardy) and 5 February 2020 (Lazio), the latter with neutralizing antibodies. The detection of IgM and/or IgG binding and neutralizing antibodies was strongly dependent on the different serological assays and thresholds employed, and they were not detected in control samples collected one year before. These findings, although gathered in a small and selected set of samples, highlight the importance of harmonizing serological assays for testing the spread of the SARS-CoV-2 virus and may contribute to a better understanding of future virus dynamics.


Vestnik MGTU ◽  
2021 ◽  
Vol 24 (4) ◽  
pp. 428-440
Author(s):  
A. A. Tumashov ◽  
A. S. Gavrilov ◽  
O. V. Chugunova ◽  
O. Yu. Bulygina

The search for equivalent flavoring sugar substitutes of a non-sugar nature is an urgent direction in the development of the technology of flour confectionery products. In the course of research, a gingerbread recipe has been developed with a partial replacement of the prescription sugar with a 15 % solution of sucralose in glycerin, which most closely correspond to the organoleptic characteristics (taste, smell, texture) of traditional flour confectionery products. The results of the organoleptic evaluation of coded prototypes of gingerbread with the involvement of experts have shown that a decrease in sugar concentration by 25 % does not lead to a statistically significant change in organoleptic parameters in comparison with control samples. Substitution of more than 30 % sugar leads to an increase in the plasticity of the dough complicating the operation of the dosing mechanisms; at the same time, the taste of the products changes (these changes are noted during the tasting assessment); their consistency becomes denser. In the process of research, the stability of the quantitative and qualitative properties of gingerbread during storage has been proved. Experimental samples of gingerbread with 25 % reduced sugar content retain all the indicators established by GOST for their storage for 90 days without statistically significant changes. The decomposition of sucralose in the manufacture of the dough is 0.1 %, in the baking process - 2.6 %, during storage for 120 days - 6.7 % (of the loaded product). The developed recipe allows enterprises to expand the range of confectionery products with reduced sugar content.


2021 ◽  
Vol 13 (4) ◽  
pp. 457-464
Author(s):  
Sergey V. Vasin ◽  
◽  
Azat M. Nizametdinov ◽  
Viacheslav A. Sergeev ◽  
Michael S. Efimov ◽  
...  

The results of the study of the effect of the permanent magnetic field of a neodymium magnet on the polymerization process and the electrophysical characteristics of polyvinyl alcohol (PVA) films with the inclusion of multi-walled carbon nanotubes (MWCNTs) are presented. When studying the morphology of films using a scanning electron microscope, it was found that nanocomposite films with a thickness of 30 microns, cured in the presence of a magnetic field with the direction of the magnetic induction vector perpendicular to the surface of the films, have a homogeneous structure, while a significant number of MWCNTs agglomerations are observed in control samples of films. Measurements of the conductivity of films in the direction of the MWCNTs orientation at direct and alternating current showed that the conductivity of films obtained in a magnetic field significantly (by almost two orders of magnitude) exceeds the conductivity of control samples. The obtained results are analyzed on the basis of known models of electrical conductivity of nanocomposites with oriented MWCNTs. The degree of orientation of the MWCNTs during the curing of films in a magnetic field is estimated, taking into account the increase in the viscosity of the nanocomposite during the curing process.


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