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Within the frequency range of 30 to 105 Hz and temperatures of 18 to 80 °C, the dielectric properties of linear low-density polyethylene with impurities of flame retardant (20 wt.%) and multilayer carbon nanotubes (1.5 wt.%) were investigated using the oscilloscopic method. This concentration value of carbon nanotubes slightly exceeds the concentration of nanotubes (1%), at which the percolation transition begins for the dependence of the polymer electrical conductivity on the content of nanotubes. It has been shown that the frequency dependence of electrical conductivity can be approximated by two exponential dependences. It has been found that when the sample is cooled, changes in the values of dielectric permittivity and electrical conductivity do not occur in the same way as when heated. The temperature dependences of conductivity for low (10² Hz) and high (104 Hz) frequencies have been obtained. [ABSTRACT FROM AUTHOR]

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Influence of Cu6PS5І nanoparticles on the dielectric properties of planarly oriented 6СВ liquid crystal (LC) is studied in the 10–106-Hz frequency range. Introduction of the nanoparticles is shown to result in an increase of the electric conductivity. Contrary to 6СНВТ LC, the conductivity monotonously depends on the nanoparticles’ concentration. The main reason of the much greater influence of Cu6PS5І nanoparticles on the 6СВ conductivity in comparison with 6СНВТ is related to a greater dissociation coefficient of Cu6PS5І in 6СВ than in 6СНВТ. This is confirmed by the fact that the dipole moment of the 6СВ molecules is greater than that of the 6СНВТ molecules. [ABSTRACT FROM AUTHOR]

Within the frequency range 10...106 Hz, the influence of Cu6PS5I nanoparticles on the dielectric properties of planar oriented liquid crystal 6CHBT has been studied. It has been shown that nanoparticles lead to an increase in conductivity, but the conductivity dependence on concentration is non-monotonic function. It has been suggested that the reason of non-monotonic dependence of conductivity of 6CHBT on the concentration of nanoparticles is significant influence of ion adsorption on the nanoparticle surface and increase in the viscosity of liquid crystal when introducing nanoparticles. [ABSTRACT FROM AUTHOR]

Studied in this work has been the effect of nanoparticles -- magnetite and single-wall carbon nanotubes -- separately and together on the conductivity of nematic liquid crystal 6CHBT dispersed in polyvinyl alcohol. Morphology of these films was analyzed using an electron microscope. When using selected technologyof homogenizing the mixture components, there takes place formation of liquid crystals dispersed in the polymer matrix with the average sizes of liquid-crystal droplets close to 500 nm (nano-PDLC). It has been found that simultaneous introduction of magnetite and nanotubes results in lowering the conductivity of nano-PDLC as compared to the total conductivity of nano-PDLC with each kind of nanoparticles separately. It has been suggested that the main mechanism of this effect lies in formation of deep centers for electron capture by complexes with different types of nanoparticles, which leads to a decrease in electronic conductivity through the polymer matrix. [ABSTRACT FROM AUTHOR]

Objective: Androgen deprivation therapy (ADT) reduces muscle and bone mass, increasing frailty in men with prostate cancer. The liver mediates the whole body anabolic effects of testosterone. Based on first-pass metabolism, liver-targeted testosterone treatment (LTTT) entails oral delivery of a small dose of testosterone that does not raise peripheral blood testosterone levels. LTTT reduces blood urea and stimulates protein anabolism in hypogonadal men and postmenopausal women. We investigated whether LTTT prevents loss of lean and bone mass during ADT., Method: A 6-month, double-blind, placebo-controlled study of testosterone 40 mg/day in 50 men. Primary outcome measures were lean mass and bone mineral content (BMC). Testosterone, urea and prostate-specific antigen (PSA) were monitored. Patients were withdrawn if PSA exceeded 4 ng/mL., Results: 42 patients completed the study. Mean (95% CI) testosterone rose during LTTT but not placebo treatment [∆ 2.2 (1.3-3.0) vs -0.7 (-1.5 to 0.2) nmol/L; P  < 0.01]. Mean PSA level did not change significantly during either treatment. Blood urea fell [∆ -0.4 (-0.9 to -0.1) mmol/L] during LTTT but not placebo [∆ 0.05 (-0.8 to 0.9) mmol/L]. BMC [∆ 49 (5 to 93) g; P  < 0.02] and lean mass [∆ 0.8 (-0.1 to 1.7) kg; P  = 0.04) increased compared to placebo. Five patients on LTTT withdrew from increased PSA levels, all returning to baseline levels., Conclusion: LTTT shows promise as a simple therapy for preventing sarcopenia and bone loss during ADT. LTTT may induce reversible PSA rise in some patients. Further studies are required to optimize LTTT dose in ADT. LTTT has potential application in other catabolic states in men and women., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society.)

The use of circulating tumor cells (CTCs) and circulating extracellular vesicles (EVs), such as exosomes, as liquid biopsy-derived biomarkers for cancers have been investigated. CTC enumeration using the CellSearch based platform provides an accurate insight on overall survival where higher CTC counts indicate poor prognosis for patients with advanced metastatic cancer. EVs provide information based on their lipid, protein, and nucleic acid content and can be isolated from biofluids and analyzed from a relatively small volume, providing a routine and non-invasive modality to monitor disease progression. Our pilot experiment by assessing the level of two subpopulations of small EVs, the CD9 positive and CD63 positive EVs, showed that the CD9 positive EV level is higher in plasma from patients with advanced metastatic prostate cancer with detectable CTCs. These data show the potential utility of a particular EV subpopulation to serve as biomarkers for advanced metastatic prostate cancer. EVs can potentially be utilized as biomarkers to provide accurate genotypic and phenotypic information for advanced prostate cancer, where new strategies to design a more personalized therapy is currently the focus of considerable investigation., (© 2017 Wiley Periodicals, Inc.)

Gp600/megalin is an endocytic receptor belonging to the low-density lipoprotein receptor family. Up or down regulation of this protein were observed in certain disease states. To understand the mechanisms that control gp600/megalin gene expression, we cloned and functionally characterized a 738-bp fragment of the 5'-flanking region of rat gp600/megalin gene. A transcription start site was mapped to 33 bp downstream of TAGAAA sequence (TATA-like box). Multiple transcription factor binding sites were identified. Serial 5' deletions and transient transfection assays showed that the deletion fragment containing the Sp1 site proximal to the TATA-like box and a JCV repeat retained 80% of the promoter activity. Individual mutations of the proximal Sp1 site and JCV repeat reduced the promoter activity by 60 and 34% respectively. Double mutations of the proximal Sp1 site and JCV repeat produced a dramatic 80% reduction in the promoter activity. However, deletions and mutations or double mutations of other transcription factor binding sites in the promoter region had a minor effect on the promoter activity. These results indicate that the combination of proximal Sp1 site and the JCV repeat are necessary for activation of gp600/megalin expression. Moreover, Sp1 and Sp3 proteins interacted with the proximal and the distal Sp1 sites in the nuclear extracts of gp600/megalin expressing cell lines. TCF site seems to be involved in negative regulation of this promoter but no nuclear protein(s) were found to bind to this site. In addition, Ap2 site responsible for 28% promoter activity is able to bind two dominant unknown nuclear proteins. This functional characterization of the regulation of gp600/megalin gene is likely to advance the knowledge of the regulation of this gene in health and disease.

70 lonely patients 60-83 years old were examined. Loneliness in the disintegrated first group (54 patients) resulted from the disintegrated family (the patients were early married). The loneliness in the second group was determined by the absence of their own family (16 patients). The main factors leading to loneliness were such diseases as schizophrenia and epilepsy, paranoic disorders of persecutive character directed to the nearest family, hypochondric depression, psychopathic-like disturbances, mental defect, personality disorders in premorbid state. Among social-psychologic factors the following ones had a significance: underestimation of the mental disorders in patients by their relatives, conflicts in the family, the patient's negative orientation to marriage, their deep emotional interrelation with the parents in young and mature age, alcoholism of married couple and special psychopathic features of the relatives. The events relating with the old age (loss of elderly couple), separation with adult children and parents, bad domestic living conditions were of less significance.