Settlement of Soil Reinforced with Vertical Fiberglass Micro-Piles

This article is dedicated to investigating the properties of soil after its reinforcement with fiberglass elements through large-scale laboratory plate-load tests of various samples that varied in the numbers and lengths of the reinforcing elements. The investigation of the vertical elements considered the diameter increase at the bottom toe by using widening washers. The results were compared relative to each other and to the theoretical calculation results. The theoretical calculations for the settlements were undertaken based on the authors’ proposed method. The method considers the number, shape, area and material of the strengthening elements using a pre-proposed reinforcement area factor µ. This pre-established factor was calculated with reference to the elements’ geometry—the diameter of the vertical elements and the bottom’s washer diameter—which determined the reinforcement area. A comparison between the reinforced and reference soft sandy soil samples indicated a 25% increase in the deformation modulus after the reinforcement process at a pressure of 25 kPa. Samples with µ ranging from 1.20 to 1.43 were 55–65% stiffer than samples with µ equal to 0.69 at a pressure of 100 kPa. The comparative analysis of the calculated results and the actual laboratory PLT test results was adequate for use for further development.     

Influenza B: Prospects for the Development of Cross-Protective Vaccines

In this review, we analyze the epidemiological and ecological features of influenza B, one of the most common and severe respiratory infections. The review presents various strategies for cross-protective influenza B vaccine development, including recombinant viruses, virus-like particles, and recombinant proteins. We provide an overview of viral proteins as cross-protective vaccine targets, along with other updated broadly protective vaccine strategies. The importance of developing such vaccines lies not only in influenza B prevention, but also in the very attractive prospect of eradicating the influenza B virus in the human population.     

Differential scanning calorimetric study of antibiotic distamycin A binding with chromatin within isolated rat liver nuclei

Context: Natural oligopeptide antibiotic distamycin A (Dst) biosynthesized by Streptomyces distallicus is traditionally used in medical practice as an anti-inflammatory and antitumour drug.

Objective: Dst was investigated for its effect on the structural components of native chromatin directly within isolated rat liver nuclei in the presence of physiologically significant cations (magnesium or spermine and spermidine).

Materials and methods: Differential scanning calorimetry (DSC) was used to study the Dst action at molar ratio Dst/DNA?=?0.1 and 0.15?mM Dst on the melting profile of nuclei suspension in different conditions.

Results: Results showed that the thermodynamic parameters of control nuclei in the presence of polyamines or Mg^2+?were different. The incubation of nuclei with Dst raised transition temperatures of relaxed (peak II) and topologically constrained DNA (peak III) by 6–8?°C and decreased by 2–4?°C that of core-histones (peak I). The total excess transition enthalpy (ΔH_exc) in buffer with polyamines (24.7?kJ/mol DNA nucleotides) increased by1.5 times versus control but in buffer with Mg²⁺, the value of ΔH_exc (35.8?kJ/mol DNA nucleotides) remained unchanged.

Conclusions: The association of Dst with chromatin in the nucleus weakens histone-DNA contacts and causes additional strengthening of interaction between two complementary DNA chains. Our results contribute towards validation of DSC to test drug ability to modulate chromatin structure in the physiological environment and to clarify the mechanism of these modulations.     

Genetic stability of Brucella abortus S19 and RB51 vaccine strains by multiple locus variable number tandem repeat analysis (MLVA16)

The aims of the present study were (i) to assess the in vitro genetic stability of S19 and RB51 Brucella abortus vaccines strains and (ii) to evaluate the ability of multiple-locus variable-number tandem repeat (VNTR) analysis (MLVA) as a tool to be used in the quality control of live vaccines against brucellosis. Sixty-three batches of commercial S19 (n = 53) and RB51 (n = 10) vaccines, produced between 2006 and 2009, were used in this study. S19 and RB51 vaccines were obtained from, respectively, seven and two different manufacturers. Ten in vitro serial passages were performed on reference strains and on selected batches of commercial vaccines. All batches, reference strains and strains of serial passages were typed by the MLVA16. The results demonstrated that B. abortus S19 and RB51 vaccine strains are genetically stable and very homogeneous in their respective groups. Anyway, batches of S19 from one manufacturer and batches of RB51 from another presented genotypes distincts from the reference vaccine strains. In both cases, differences were found on locus Bruce07, which had addition of one repeat unit in the case of S19 batches and the deletion of one repeat unit in the case of RB51 batches. In summary, MLVA16 proved to be a molecular tool capable of discriminating small genomic variations and should be included in in vitro official tests.     

Melatonin and Metformin Failed to Modify the Effect of Dacarbazine in Melanoma

Lessons Learned

• Melatonin did not increase the efficacy of systemic chemotherapy in melanoma.
• Metformin did not increase the efficacy of systemic chemotherapy in melanoma.

     

Nanocrystalline TiO2 doped by small amount of pre-synthesized colloidal CdS nanoparticles for photocatalytic degradation of 1,2,4-trichlorobenzene

The chemical stability and hydrophobic nature of chloroarenes make them a persistent environmental hazard. Modeling of 1,2,4-trichlorobenzene (1,2,4-TCB) degradation in alcohol-water solution under UV irradiation was carried out with the aim of probing how the 1,2,4-TCB might behave in the environment. The photocatalytic activity of both bare TiO₂ and TiO₂ doped by colloidal CdS nanoparticles synthesized by the sol-gel method has been investigated in the processes of 1,2,4-TCB photodegradation in the aqueous protic solvent. Non-sensitized TiO₂ cannot be regarded as catalyst for the 1,2,4-TCB photodecomposition. On the contrary, the CdS/TiO₂ composite accelerated the 1,2,4-TCB photodegradation process. The concentration of CdS/TiO₂ was shown to effect on the 1,2,4-TCB photolysis mechanisms, which resulted in the quantitative ratios of the 1,2,4-TCB photolysis products.     

Body weight is not always a good predictor of longevity in mice

There have been some observations that low body weight and a low level of some hormones (e.g. IGF-1) during the first half of life are predictors of longer life in mice. However, contradictions in the available data on the biomarkers of aging and predictors of longevity have shown that the research in these fields has become a controversial pursuit. In our study we addressed the following questions: (i) Can particular physiological parameters (body weight, food intake, estrus function, body temperature, incidence of chromosome aberrations in bone marrow cells) measured at the age of 3 and 12 months be a predictor of longevity and the rate of tumor development in five strains of mice? (ii) Can a heavy body weight at the age of 3 and 12 months be a predictor of longevity and high tumor risk in five strains of mice? Mice of five strains-CBA, SHR, SAMR, SAMP and transgenic HER-2/neu (FVB/N)-were under observation from the age of 2-3 months until natural death. Body weight and temperature, food consumption, and estrous cycle were longitudinally studied in all animals. Tumors discovered at autopsy were studied morphologically. We calculated the life span's parameters (mean, maximum, mortality rate, mortality rate doubling time) as well as their correlation with other parameters studied. The longest living CBA mice have the lowest body weight at the ages of 3 and 12 months, the lowest food consumption, body temperature, incidence of chromosome aberrations and spontaneous tumor incidence. In comparison with all other mouse strains they also have the latest disturbances in estrus function and highest body weight gain. The shortest living transgenic HER-2/neu mice have the lowest weight at the ages of 12 months, the lowest body weight gain, maximal body temperature, the most rapid disturbances in estrus function and the highest incidence of chromosome aberrations and tumor incidence in comparison to all other mouse strains. Our findings have shown that heavier body weight at the age of 12 months is a predictor of longevity in female CBA and SAMP mice but not in SHR, SAMR and HER-2/neu mice. Excessive body weight at the ages of 3 or 12 months is not a predictor of increased tumor risk in the strains studied. In general, the existence and direction of a significant correlation between body weight and life span depends upon the animals' age and genotype.