Head and neck cancer is the sixth most common malignancy worldwide, with the relatively low 5-year survival rate, mainly because it is diagnosed at a late stage. Infection with HPV is a well known ...aetiology, which affects the nature of these cancers and patients' survival. Besides, it is considered that the main driving force for this type of cancer could be epigenetics. In this study we aimed to find potential epigenetic biomarkers, by integrating miRNome, methylome, and transcriptome analyses. From the fresh head and neck cancer tissue samples, we chose a group for miRNome, methylome and transcriptome profiling, in comparison to adequate control samples. Bioinformatics analyses are performed in R v4.2.2. Count normalisation and group differential expression for mRNA and the previously obtained miRNA count data was performed with DESeq2 v1.36. Gene set enrichment analysis was performed and visualised using gProfiler2 v0.2.1 Identification of miRNA targets was performed by querying in miRTarBase using multiMiR v1.18.0. Annotation of CpG sites merging into islands was obtained from RnBeads.hg19 v1.28.0. package. For the integrative analysis we performed kmeans clustering using stats v4.2.2 package, using 8-12 clusters and nstart 100. We found that transcriptome analysis divides samples into cancers and controls clusters, with no relation to HPV status or cancer anatomical location. Differentially expressed genes (n = 2781) were predominantly associated with signalling pathways of tumour progression. We identified a cluster of genes under the control of the transcription factor E2F that are significantly underexpressed in cancer tissue, as well as T cell immunity genes and genes related to regulation of transcription. Among overexpressed genes in tumours we found those that belong to cell cycle regulation and vasculature. A small number of genes were found significantly differentially expressed in HPV-positive versus HPV-negative tumours (for example NEFH, ZFR2, TAF7L, ZNF541, and TYMS). In this comprehensive study on an overlapping set of samples where the integration of miRNome, methylome and transcriptome analysis were performed for head and neck cancer, we demonstrated that the majority of genes were associated exclusively with miRNome or methylome and, to a lesser extent, under the control of both epigenetic mechanisms.
Using a combustion synthesis, the range of achievable textures is broader than using conventional synthesis methods and can be controlled more successfully. As a tool allowing the achievement and ...control of desired textures, here we bring about wet chemistry synthesis using aluminium nitrate nonahydrate (ANN) precursor systematically combined with different fuels (amino acids). The amino acids; glycine (G), alanine (A) and asparagine (N) have been specifically selected in order to show the role of gradual increase in their: (1) molar mass, (2) enthalpy of combustion, (3) amine groups content and (4) ratio to ANN. Detailed (micro) structural and thermal characterisations confirm that the nanocrystalline character and thermomechanical stability were not diminished in the course of this synthesis. The conditions leading to development of different morphologies from gels to powders were found to be heavily under the influence of fuel/oxygen ratio, i.e. of the smouldering versus flaming mechanism of the combustion. Higher content of nitrates (predominately from amino-rich amino acids) strongly promoted auto-combustion behaviour. As-derived alumina precursors have been thermally treated at various temperatures (quenched and soaked), to monitor γ- and α-alumina crystallisation, with respect to the development of morphology. Different texture types have been observed, such as porous wormhole, porous and porous expanded flakes. Higher fuel levels promote specific surface increase. This combustion synthesis allows facile tailoring of nanocrystalline γ-alumina with different morphological features, whereas samples having optimal parameters were suitable for catalyst support application on behalf of rapid sorption performance.
Exposure to low levels of a toxic metal lead (Pb) affects human health, and its effect as an endocrine disruptor has been reported. However, the precise role of Pb in endocrine health is still ...unclear because no dose-response relationship has been established for such an effect. The present study aimed to examine blood Pb levels (BLLs) in relation to serum levels of free triiodothyronine (fT3), free thyroxine (fT4), thyroid stimulating hormone (TSH), and insulin in 435 nonoccupationally exposed Serbian subjects (218 women, 217 men, 18–94 years of age, mean age 48). In addition, benchmark dose (BMD) values were calculated for these endocrine endpoints using the PROAST 70.1 software. An explicit dose-response dependency between BLL and TSH, fT3, fT4, testosterone, and insulin serum levels was evident from BMD modelling. The results support the positive association between BLLs and serum insulin levels, with observed dose-response and calculated BMD values of 1.49 and 0.74 μg Pb/dL in males and females, respectively. Collectively, our findings reported potential endocrine-disrupting effects of Pb at the environmental exposure levels experienced by current Serbian population. They also strengthen the notion that the blood Pb threshold level for an endocrine effect is low.
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•An explicit dose-response dependency between hormone and BLL was evident.•Derived BMDLs for insulin were 1.49 (males) and 0.74 μg Pb/dL (females).•Pb threshold established for its endocrine effects might be very low.•The results provide new insight into human health risk assessment of low Pb exposure.
The catalytic activity and properties of hydrothermally derived nanocrystalline ceria, as well as ceria doped substitutionally by 10 mol. % of Mn, Fe, Co, Ni, Cu and Zn, were investigated.
It was ...determined that in the course of synthesis and under the synthesis conditions applied Mn, Cu and Zn enter the ceria crystal lattice, while for other investigated metals additional crystal phases appear. The presence of a foreign cation did not affect the ceria crystallite size, particle size or specific surface area. Nanocatalysts with crystallite and particle sizes close to 5 nm and with specific surface area around 200 m2 g-1 were prepared. However, except for Mn, a negative influence of dopants on coarsening resistance has been observed. Doping with Cu and Mn significantly enhanced the ceria catalytic activity, slight improvement was observed for samples with Zn and Fe, while samples with Ni and Co showed a decreased catalytic activity.
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•Mn, Cu and Zn enter the ceria lattice, while for Fe, Co and Ni additional crystal phases appear.•Ceria with crystallite size of ~5 nm and specific surface area between 180 and 202 m2 g−1 was obtained.•Negative influence of dopants on sintering resistance has been observed.•Lattice expansion of doped samples have been observed for thermally treated samples.•Doping with Cu and Mn enhance ceria catalytic activity for toluene oxidation process.
Lowering the constitutive domains of semiconducting oxides to the nano-range has recently opened up the possibility of added benefit in the research area of sensing materials, in terms both of ...greater specific surface area and pore volume. Among such nanomaterials, ceria has attracted much attention; therefore, we chemically derived homogeneous ceria nanoparticle slurries. One set of samples was tape-casted onto a conducting glass substrate to form thin-films of various thicknesses, thereby avoiding demanding reaction conditions typical of physical depositions, while the other was pressed into pellets. Structural and microstructural features, along with electrical properties and derivative humidity-sensing performance of ceria thin-films and powders pressed into pellets, were studied in detail. Particular attention was given to solid-state impedance spectroscopy (SS-IS), under controlled relative humidity (RH) from 30%-85%, in a wide temperature and frequency range. Moreover, for the thin-film setup, measurements were performed in surface-mode and cross-section-mode. From the results, we extrapolated the influence of composition on relative humidity, the role of configuration and thin-film thickness on electrical properties, and derivative humidity-sensing performance. The structural analysis and depth profiling both point to monophasic crystalline ceria. Microstructure analysis reveals slightly agglomerated spherical particles and thin-films with low surface roughness. Under controlled humidity, the shape of the conductivity spectrum stays the same along with an increase in RH, and a notable shift to higher conductivity values. The relaxation is slow, as the thickness of the pellet slows the return of conductivity values. The increase in humidity has a positive effect on the overall DC conductivity, similar to the temperature effect for semiconducting behavior. As for the surface measurement setup, the thin-film thickness impacts the shape of the spectra and electrical processes. The surface measurement setup turns out to be more sensitive to relative humidity changes, emphasized with higher RH, along with an increase in thin-film thickness. The moisture directly affects the conductivity spectra in the dispersion part, i.e., on the localized short-range charge carriers. Moisture sensitivity is a reversible process for thin-film samples, in contrast to pellet form samples.
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