A Method to Record the Surface Temperature Distribution of the Skin as a Safe and Ergonomic Approach to Diagnosis and Monitoring in Breast Cancer

Biophysics - Abstract—This article discusses the relevant results on early and safe detection of breast cancer with a thermal volume tomography (TVT) device produced in Russia. The device...     

How electron interference can be used in probing the surface of minute bioobjects and in fast reading of polynucleotides

A method is proposed for examining the surface of small biological objects such as macromolecules and their complexes. Based on interference of low-energy electrons, it allows constructing analogs of optical holograms but with a resolution on the order of interatomic distances. A set of such holograms obtained at different electron energies can provide sufficient information for identifying the surface groups of the object. Thus the method can be used for fast reading of e.g. polynucleotide sequences.     

Many-worlds interpretation of quantum theory and fundamental problems of biophysics

The main aspects connected with the many-worlds interpretation of quantum theory are discussed in the article. A possible relation of the interpretation with fundamental biological problems is emphasized. The context of the many-worlds interpretation is discussed in the frames of the so-called “wave function reduction” problem. Thus, some difficulties that arise when we try to imagine how a wave function is reduced in the many-worlds interpretation, are focused on. It is shown that explanations suggested by now as to how the “wave function reduction” happens cannot claim to be the final answer to this question, even though they are not formally contradictory.     

Reparative and neoplastic spheroid cellular structures and their mathematical model

Spheroid cell structures in the cell cultures have been described and are used for studying cell-cell and cell-matrix interactions. At the same time, spheroid cell structure participation in the repair and development of cancer in vivo remains unexplored. The aim of this study was to investigate the cellular composition of spherical structures and their functional significance in the repair of squamous epithelium in human papilloma virus-associated cervical pathology - chronic cervicitis and cervical intraepithelial neoplasia 1–3 degree, and also construct a mathematical model to explain the development and behavior of such spheroid cell structure.     

Fatty Acid- and Cholesterol Transporter Protein Expression along the Human Intestinal Tract

Background

Protein distribution profiles along the human intestinal tract of transporters involved in the absorption of cholesterol and long-chain fatty acids (LCFA) have been scarcely evaluated.

Methodology/Principal Findings

In post-mortem samples from 11 subjects, intestinal transporter distribution profiles were determined via Western Blot. Differences in transporter protein levels were statistically tested using ANOVA and Tukey''s Post Hoc comparisons. Levels in all segments were expressed relative to those in duodenum. Except for ABCG5 and FATP4, levels (mean±SEM) were the highest in the ileum. For ABCA1, ileal levels (1.80±0.26) differed significantly from those in duodenum (P = 0.049) and proximal colon (0.92±0.14; P = 0.029). ABCG8 levels in ileum (1.91±0.30) differed from those in duodenum (P = 0.041) and distal colon (0.84±0.22; P = 0.010) and jejunum (1.64±0.26) tended to be higher than distal colon (0.84±0.22; P = 0.087). Ileal NPC1L1 levels (2.56±0.51) differed from duodenum levels (P = 0.019) and from distal colon (1.09±0.22; P = 0.030). There was also a trend (P = 0.098) for higher jejunal (2.23±0.37) than duodenal NPC1L1 levels. The levels of ABCG5 did not correlate with those of ABCG8. FAT/CD36 levels in ileum (2.03±0.42) differed from those in duodenum (P = 0.017), and proximal and distal colon (0.89±0.13 and 0.97±0.15 respectively; P = 0.011 and P = 0.014). FABPpm levels in ileum (1.04±0.13) differed from proximal (0.64±0.07; P = 0.026) and distal colon (0.66±0.09; P = 0.037).

Conclusions/Significance

The distribution profiles showed a bell-shape pattern along the GI-tract with the highest levels in ileum for ABCA1, ABCG8, NPC1L1, FATCD36 and FABPm, suggesting a prominent role for ileum in transporter-mediated uptake of cholesterol and LCFAs.     

DNA sequencing using specific long-range interaction between macromolecules

On the basis of the theory of specific long-range interaction between long molecules, an approach has been elaborated for «fast reading» of nucleotide sequences in one DNA molecule. First, a stretching force is applied to the molecule that causes its unwinding from B-form to S-form. Then, the molecule is placed in the stretched state on a support. After this, the electrostatic potential is estimated in a space along the DNA filament. The information obtained is sufficient for deducing the nucleotide sequence. Another approach to the «reading» of information reduces to measurement of the deformation of filament elements induced by the electric field from the electrode that stretches the filament by an alternating current applied.     

Regulation of glycogen metabolism in rat respiratory muscles during exercise

The effect of prolonged exercise on the glycogen level in the respiratory muscles (diaphragm--D, external intercostal--IE and internal--II) has been studied in four groups of rats: 1-control, 2-fasted for 24 h, 3-treated with nicotinic acid and 4-treated with propranolol. There was a sharp reduction in glycogen level in each muscle after 30 min exercise in the control and fasted groups. Exercise till exhaustion further lowered the glycogen level in D in the control group and in IE and II in the fasted group. In the fasted group, the level of glycogen in each muscle, at rest, and after 30 min exercise, and in IE and II muscles after exercise till exhaustion was lower than in the control group. Nicotinic acid did not affect the glycogen level either at rest or during exercise as compared with the control group. Propranolol increased the glycogen level in the muscles at rest and during 30 min exercise. It partially prevented glycogen mobilization in D and IE and fully in II during exercise till exhaustion. In the control group, 24 and 48 h after exercise till exhaustion, the level of glycogen in each muscle exceeded the resting control value. It is concluded that exercise-induced glycogen metabolism in the respiratory muscles differs in some respects from that in the limb or heart muscles.     

Bactericidal activities of the cationic steroid CSA-13 and the cathelicidin peptide LL-37 against Helicobacter pylori in simulated gastric juice

Background  

The worldwide appearance of drug-resistant strains of H. pylori motivates a search for new agents with therapeutic potential against this family of bacteria that colonizes the stomach, and is associated with adenocarcinoma development. This study was designed to assess in vitro the anti-H. pylori potential of cathelicidin LL-37 peptide, which is naturally present in gastric juice, its optimized synthetic analog WLBU2, and the non-peptide antibacterial agent ceragenin CSA-13.     

Long-range interactions between macromolecules in ordered media

The results of theoretical calculations of interactions between macromolecules dissolved in ordered media such as liquid crystals and biological membranes (lipid bilayers) are reviewed. Expressions for the potentials of interactions between macromolecules of different shape incorporated into nematic liquid crystals, thin films, and lipid mono- and bilayers were derived. In addition to exact expressions, simple evaluating formulae are given. The two-dimensional "gas" of macromolecules swimming on the membrane was considered, and the expression of state for this "gas" was derived. It was shown that in the "gas", phase transitions accompanied by the formation of two-dimensional clusters may occur. The estimates of critical density at which these transitions occur are given.