Are CD44⁺/CD24⁻ cells the assumed cancer stem cells in breast cancer?

Identification and characterization of the population of cancer stem cells (CSC) depends on several cellular markers, which combination is specific for the phenotype of CSC in the corresponding tumor. Several markers of CSC have already been identified in breast cancer (BC), but there are no universal indicators that could specifically identify the CSC in BC. Aims: To determine the validation of the CSC model for cell surface markers such as CD44 and CD24 and their clinical significance. Materials and Methods: Primary tumor samples of 45 patients with invasive BC without chemotherapy prior to surgery exposure were examined in paraffin blocks. CD44 and CD24 antigens expression was evaluated by the percentage of positive cells using different chromogens and the MultiVision detection system by immunohistochemical method. In this research the evaluation was determined by the following criteria: (-), negative — expression in < 10% of tumor cells; (+), positive — expression in ≥10% of cells. The same scoring system was applied for the expression of CD44⁺/CD24⁻. Results: 62.2% of investigated patients are patients older than 50 years and most of them with stage II of disease (71.0%) and luminal tumor subtypes (68.9%). We analysed the expression of CD44, CD24 and CD44⁺/CD24⁻ for different patients with dividing them into two groups. The group A consists of patients with unfavorable prognosis (relapses and metastases have occurred in the first three years after diagnosis), and the group B — with a favourable prognosis (the development of metastases after three years). Median disease-free survival in the group A is 19 months, in the group B — 46 months. The difference between the overall survival (OS) curves in the groups A and B is statistically significant (p < 0.001), the risk of death was higher in the group A (hazard ratio (HR) 5.9; confidence interval (CI) 2.3–15.2). The content of CD44 cells did not differ statistically between groups A and B (p = 0.18), but there was a tendency for increasing in OS with the existence of CD44+ cells (p = 0.056). The distribution of the expression of CD24 marker did not differ between the groups (p = 0.36) as well as the OS curves (p = 0.59). Analysis of the expression of CD44+/CD24⁻ which were considered as possible CSC, revealed a paradoxical increase (p = 0.03) of the frequency in patients of the group B (40.9%) compared to the group A (8.7%). Nevertheless, the comparison of the clinical outcomes did not reveal a statistically significant difference in the survival curves in the groups with existence and absence of CD44⁺/CD24⁻ expression (p = 0.08). The analysis showed the increasing of the risk of worse clinical outcomes in the cases of expression absence of CD44⁺/CD24⁻ (HR 2.8; CI 1.1–6.8). Conclusions: As a result of our research, the analysis of the quantity of assumed stem cells of the BC, which were identified by immunohistochemistry as CD44 and CD24 cells, failed to detect a statistically significant relation between groups of patients with different prognosis, and the identification of their expression is not enough for the characteristics of CSC. The obtained data demonstrating the worst clinical outcome in the cases of absence of CD44⁺/CD24⁻ expression apparently require further investigations and the validation of the immunohistochemical method with the determination of the cut-off line in defining of CD44 and CD24 status

Nucleation and Growth in Nanosystems: Some New Concepts

Review covers some new concepts in theory and modelling of the initial stages of solid-state reactions in thin films, multilayers, nanoparticles, and bulk nanocrystalline materials. The following topics are included: possibility of oscillatory ordering and nucleation in the sharp concentration gradient; criteria of suppression/growth of stable and metastable phases at the nucleation stage; possible nucleation modes in sharp concentration gradient and their competition; competitive nucleation and decomposition in small volumes; criteria of unambiguous choosing the parameters of discontinuous precipitation based on the balance and maximum production of the entropy; formation of nanostructure under uniaxial compression of single-crystalline alloy.Обзор содержит набор некоторых новых концепций в теории и моделировании начальных стадий твердофазных реакций в тонких пленках, мультислоях, наночастицах и в объеме нанокристаллических материалов. Обсуждаются следующие темы: возможность осцилляционного упорядочения и зародышеобразования в поле градиента концентрации; критерий подавления/роста стабильных и метастабильных фаз на стадии зародышеобразования; возможность различных мод зародышеобразования в поле градиента концентрации и их конкуренция; конкурентное зародышеобразование и распад в малых объемах; критерий однозначного выбора параметров ячеистого распада, основанный на балансе и максимуме производства энтропии; формирование наноструктур под воздействием одноосного сжатия монокристаллического сплаваОгляд містить набір деяких нових концепцій в теорії і моделюванні початкових стадій твердофазних реакцій у тонких плівках, мультишарах, наночастинках та в об’ємі нанокристалічних матеріалів. Обговорено наступні теми: можливість осциляційного впорядкування і зародкоутворення в полі градієнта концентрації; критерій пригнічення/росту стабільних і метастабільних фаз на стадії зародкоутворення; можливість різних мод зародкоутворення в полі градієнта концентрації та їх конкуренція; конкурентне зародкоутворення і розпад в малих об’ємах; критерій однозначного вибору параметрів коміркового розпаду, що базується на балансі та максимумі виробництв

The COMPASS Experiment at CERN

The COMPASS experiment makes use of the CERN SPS high-intensitymuon and hadron beams for the investigation of the nucleon spin structure and the spectroscopy of hadrons. One or more outgoing particles are detected in coincidence with the incoming muon or hadron. A large polarized target inside a superconducting solenoid is used for the measurements with the muon beam. Outgoing particles are detected by a two-stage, large angle and large momentum range spectrometer. The setup is built using several types of tracking detectors, according to the expected incident rate, required space resolution and the solid angle to be covered. Particle identification is achieved using a RICH counter and both hadron and electromagnetic calorimeters. The setup has been successfully operated from 2002 onwards using a muon beam. Data with a hadron beam were also collected in 2004. This article describes the main features and performances of the spectrometer in 2004; a short summary of the 2006 upgrade is also given.Comment: 84 papes, 74 figure

Optimization methods for correcting the duration of the anovulatory period of cattle

Post-calving anestrus leads to serious economic losses and is the reason for the animal culling. Deficiency of estrogen and hypofunctional state of the ovaries due to negative energy balance, as well as violations of the timing of postpartum involution of the uterus are considered the leading causes of an extended anovulatory period in fresh cows. A comparison was made of the therapeutic efficacy of Ovsynch scheme and Ovariovit preparation when used in first heifers with post-calving anestrus against the background of ovarian hypofunction. When using Ovsynch scheme, the fertility of the first insemination was 50%; estrous cyclicity recovered in 80% of first heifers. When using Ovariovit, the fertility of the first insemination was 60%; the estrous cycle was restored in 100% of first heifers