Results of the study of intestine biocenosis in children

Department of Surgery № 2 with the course of pediatric surgery, Odessa National Medical University, Odessa, Ukraine, The 6th International Medical Congress for Students and Young Doctors, May 12-14, 2016Introduction. Changes in intestinal microbiocenosis play an important role in the development of functional disorders of the digestive tract in children. The aim of the study was to determine the diagnostic value of bacteriological studies of intestinal dysbiosis. Patients and methods. We performed a retrospective analysis of 127 results of fecal survey on dysbiosis in children aged 1 to 17 years with impaired bowel function, that turned to the Odessa Regional Children's Clinical Hospital in 2014-2015. Results. According to our research, more of the analysis on dysbiosis was conducted in patients of younger age group of 1 to 3 years ─ 68,8% of all cases. In the same age group, 81.4% examinationed children were bacteriological signs of dysbiosis of transient nature. There was a seasonal correlation of the research, since 44.8% of analyzes were carried out in the period from February to April, due to an increase in functional disorders of the digestive tract in children during this period. For the majority ofpatients (78.6%) fecal dysbiosis has been performed in occasion of functional disorders of the gastrointestinal tract. The most common conditional pathogens St. Aureus were detected in the youngest age groups: from 1 year up to 3 years ─ at 44.2%; 4 to 7 years old children ─ 42,3%. On the second place were sown fungi of the genus Candida and other yeast in 38.6% of patients, as well mainly in young children. On the third place - E.cloaceae (11,02%) and lactosonegative (10,8%) Escherichia, then Kl. Pneumoniae 9,4%, P.aeruginosa in 2.36% of patients, respectively. The remaining microorganisms disembarked in single cases. Results of analyzes, unfortunately, were ready on day 10, when was advanced clinical remission in patients and there was no need for a correction of infringements. Conclusions. Violation of intestinal microbiocenosis is most characteristic for young children, is rarely correlated with clinical data and is transient. Are most commonly defined conditional Pathogens St.Aureus and fungi of the genus Candida. However, the diagnostic value of the study is reduced due to the timing of the tests

The distribution of TP53 gene polymorphisms in chronic lymphocytic leukemia patients, sufferers of chornobyl nuclear power plant accident

Previous analyses in a cohort of Chornobyl cleanup workers revealed significantly increased radiation-related risk for all leukemia types, including chronic lymphocytic leukemia (CLL). Numerous investigations emphasized the significance of genetic susceptibility to the radiation carcinogenesis. The aim of the work was to study the distribution of TP53 single nucleotide polymorphisms (SNPs) in CLL patients exposed to ionizing radiation (IR) due to Chornobyl nuclear power plant accident and estimate their impact on disease development. Materials and Methods: The TP53 exonic and intronic SNPs were analyzed in 236 CLL patients by polymerase chain reaction and direct sequencing. The main group included 106 IR exposed CLL patients and the control group was composed of 130 IR non-exposed CLL patients. Results: Nineteen TP53 SNPs were found in the observed CLL cohort. No significant differences were found between the main and the control groups, but increased frequencies of T/T rs12947788 + G/G rs12951053 homozygotes and rs146340390 C/T variants were found among IR-exposed CLL patients compared with healthy Europeans (data from the 1000 Genomes Project). Rare nucleotide substitution rs146340390 (c.665C>T) was found only in the main group. These features were primarily typical for the most affected group of IR-exposed patients, namely, cleanup workers engaged in emergency works in the 2nd quarter of 1986. Conclusion: These preliminary findings don’t contradict the assumption on possible influence of IR on CLL development via the p53-dependent pathway. This article is a part of a Special Issue entitled “The Chornobyl Nuclear Accident: Thirty Years After”

TP53 codon 72 single nucleotide polymorphism in chronic lymphocytic leukemia

Defects in the tumor suppressor gene TP53 are known to be important in chronic lymphocytic leukemia (CLL) and TP53 inactivation is associated with a particularly aggressive form of the disease. The single nucleotide polymorphism in the TP53 gene at codon 72 (rs1042522), results in amino acid substitution influencing apoptotic potential of TP53 protein. The aim of the study was to evaluate the association of the TP53 codon 72 polymorphism and incidence of TP53 mutations in CLL patients. Methods: 261 CLL samples were analyzed by polymerase chain reaction and direct sequencing for TP53 mutations and single nucleotide polymorphism. Results: The 72Pro/Pro genotype was associated with an increased incidence of TP53 mutations in previously treated patients (OR = 2.503; 95% CI 1.142–5.487; р = 0.001). Conclusion: This study revealed that the TP53 codon 72 polymorphism may be used as a risk factor for incidence of TP53 mutations in CLL. Key Words: chronic lymphocytic leukemia, TP53 mutations, single nucleotide polymorphism

Analysis of the 3′UTR region of the NOTCH1 gene in chronic lymphocytic leukemia patients

Deregulation of NOTCH1-signalling pathway is common in chronic lymphocytic leukemia (CLL). The most of studies are focused on detection of the hotspot c.7541_7542delCT NOTCH1 mutations in exon 34, while studies of mutations in the 3′UTR region are rare. The aims of work were to evaluate the frequencies of mutations in the 3′UTR region of the NOTCH1 gene (9:136,495553-136,495994) in Ukrainian CLL patients, the distribution of rs3124591 genotypes located in that area, and association of NOTCH1 mutations with structure of B-cell receptor. Materials and Methods: Detection of mutations in the 3′UTR region of the NOTCH1 was performed by direct sequencing in 87 previously untreated CLL patients (from the total group of 237 CLL patients) with unmutated immunoglobulin heavy-chain variable (UM IGHV) genes and without mutations in hotspot regions of TP53, SF3B1, and exon 34 of NOTCH1 genes. Results: Mutations in the 3′UTR region of the NOTCH1 were revealed in three of 87 CLL patients (3.4%). Two cases with non-coding mutations were related to subset #1 of stereotyped B-cell receptors, and one case belonged to stereotyped subset #28a. Analysis with inclusion of 30 UM IGHV cases with previously detected c.7544_7545delCT mutations revealed that the frequency of UM IGHV genes of I phylogenetic clan (except IGHV1-69) was significantly increased, and the frequency of UM IGHV3 and IGHV4 genes, on the contrary, was reduced in NOTCH1-mutated cases comparing with NOTCH1-unmutated cases (p = 0.002) and the general group (p = 0.013). SNP rs3124591 did not affect the risk of CLL and survival parameters of the patients. At the same time, differences were found in the frequency of IGHV gene usage and in the structure of HCDR3 in carriers of individual genotypes. Conclusion: The frequency of NOTCH1 mutations in 3′UTR region was low. Our findings confirmed current data on the association between the structure of the B-cell receptor and the appearance of NOTCH1 mutations. Some features of HCDR3 structure were identified in carriers of TT and CC genotypes of rs3124591. Key Words: NOTCH1 mutations, 3′UTR region of the NOTCH1, rs3124591, IGHV genes

Detection of notch1 c.7544_7545deICT mutation in chronic lymphocytic leukemia using conventional and real-time polymerase chain reaction

Aim: To evaluate real-time polymerase chain reaction (PCR) assay system for detection of NOTCH1 c.7541_754delCT mutation in chronic lymphocytic leukemia (CLL) patients. Material and Methods: A total of 325 CLL patients were included in the study. Screening for NOTCH1 c.7544_7545delCT was performed using conventional PCR-based amplification refractory mutation system (ARMS) method. All 33 samples harboring c.7544_7545delCT allele and 5 negative cases as control were submitted to real-time PCR. Results: Specificity and sensitivity of two PCR techniques were comparable. NOTCH1 c.7544_7545delCT mutation was found by ARMS in 10.1% of CLL patients, which is consistent with the data of other studies. However, the results of ARMS PCR in a minority of cases (2.15%) were doubtful and required reinvestigation. Real-time PCR, being less time-consuming, showed advantage in the assessment of the amplification’s specificity (using the melting curve analysis). It also allows the quantitative assessment of NOTCH1-mutated clone. Conclusion: NOTCH1 c.7544_7545delCT mutation resulting in removal of the C-terminal PEST domain, deregulation of NOTCH1-dependent signaling pathways, has negative influence on prognosis of CLL and efficiency of therapy with anti-CD20 monoclonal antibodies. Real-time PCR allows the fast and reliable detection of c.7544_7545delCT mutation and can be used for the screening of this molecular lesion in CLL patients

Formation of Bose–Einstein magnon condensate via dipolar and exchange thermalization channels

Thermalization of a parametrically driven magnon gas leading to the formation of a Bose–Einstein condensate at the bottom of a spin-wave spectrum was studied by time- and wavevector-resolved Brillouin light scattering spectroscopy. Two distinct channels of the thermalization process related on dipolar and exchange parts of a magnon gas spectrum are clearly determined. It has been found that the magnon population in these thermalization channels strongly depends on applied microwave pumping power. The observed magnon redistribution between the channels is caused by the downward frequency shift of the magnon gas spectrum due to the decrease of the saturation magnetization in the course of injection of parametrically pumped magnons

A Statistical Study on Photospheric Magnetic Nonpotentiality of Active Regions and Its Relationship with Flares during Solar Cycles 22-23

A statistical study is carried out on the photospheric magnetic nonpotentiality in solar active regions and its relationship with associated flares. We select 2173 photospheric vector magnetograms from 1106 active regions observed by the Solar Magnetic Field Telescope at Huairou Solar Observing Station, National Astronomical Observatories of China, in the period of 1988-2008, which covers most of the 22nd and 23rd solar cycles. We have computed the mean planar magnetic shear angle (\bar{\Delta\phi}), mean shear angle of the vector magnetic field (\bar{\Delta\psi}), mean absolute vertical current density (\bar{|J_{z}|}), mean absolute current helicity density (\bar{|h_{c}|}), absolute twist parameter (|\alpha_{av}|), mean free magnetic energy density (\bar{\rho_{free}}), effective distance of the longitudinal magnetic field (d_{E}), and modified effective distance (d_{Em}) of each photospheric vector magnetogram. Parameters \bar{|h_{c}|}, \bar{\rho_{free}}, and d_{Em} show higher correlation with the evolution of the solar cycle. The Pearson linear correlation coefficients between these three parameters and the yearly mean sunspot number are all larger than 0.59. Parameters \bar{\Delta\phi}, \bar{\Delta\psi}, \bar{|J_{z}|}, |\alpha_{av}|, and d_{E} show only weak correlations with the solar cycle, though the nonpotentiality and the complexity of active regions are greater in the activity maximum periods than in the minimum periods. All of the eight parameters show positive correlations with the flare productivity of active regions, and the combination of different nonpotentiality parameters may be effective in predicting the flaring probability of active regions.Comment: 20 pages, 5 figures, 4 tables, accepted for publication in Solar Physic

Особенности генетического полиморфизма HLA-антигенов при приобретенной апластической анемии у детей

This study presents the genetic polymorphism of HLA-antigens in acquired aplastic anemia (AAA) in 147 children (85 boys и 62 girls) aged 1 to 18 with. The control group is consisted of 1700 umbilical cord blood samples of healthy newborns. The genetic polymorphism of HLA was studied in groups of children with AAA, divided by gender and age. Our results revealed distinction in HLA-markers of predisposition and sustainability to AAA. Possible differences in factors of immunogenetic predisposition suggest different mechanisms involved in the development of the disease in different groups of children and reconsider the existing model of the pathogenesis of AAA.В статье представлены результаты исследования генетического полиморфизма HLA-антигенов при приобретенной апластической анемии (ПАА) у 147 детей в возрасте от 1 до 18 лет. Контрольная группа была представлена 1700 образцами пуповинной крови условно здоровых новорожденных детей. Анализ полученных данных позволил выявить отличающиеся у детей разного пола и возраста HLA-маркеры предрасположенности и протекции к ПАА. Вероятное различие в факторах иммуногенетической предрасположенности позволяет предположить участие разных механизмов в развитии заболевания у разных групп детей и по-новому рассматривать уже имеющиеся модели патогенеза ПАА

The Renormalization Effects in the Microstrip-SQUID Amplifier

The peculiarities of the microstrip-DC SQUID amplifier caused by the resonant structure of the input circuit are analyzed. It is shown that the mutual inductance, that couples the input circuit and the SQUID loop, depends on the frequency of electromagnetic field. The renormalization of the SQUID parameters due to the screening effect of the input circuit vanishes when the Josephson frequency is much greater than the signal frequency.Comment: 11 pages, 2 figure

Probing the Role of Magnetic-Field Variations in NOAA AR 8038 in Producing Solar Flare and CME on 12 May 1997

We carried out a multi-wavelength study of a CME and a medium-size 1B/C1.3 flare occurring on 12 May 1997. We present the investigation of magnetic-field variations in the NOAA Active Region 8038 which was observed on the Sun during 7--16 May 1997. Analyses of H{\alpha} filtergrams and MDI/SOHO magnetograms revealed continual but discrete surge activity, and emergence and cancellation of flux in this active region. The movie of these magnetograms revealed two important results that the major opposite polarities of pre-existing region as well as in the emerging flux region (EFR) were approaching towards each other and moving magnetic features (MMF) were ejecting out from the major north polarity at a quasi-periodicity of about ten hrs during 10--13 May 1997. These activities were probably caused by the magnetic reconnection in the lower atmosphere driven by photospheric convergence motions, which were evident in magnetograms. The magnetic field variations such as flux, gradient, and sunspot rotation revealed that free energy was slowly being stored in the corona. The slow low-layer magnetic reconnection may be responsible for this storage and the formation of a sigmoidal core field or a flux rope leading to the eventual eruption. The occurrence of EUV brightenings in the sigmoidal core field prior to the rise of a flux rope suggests that the eruption was triggered by the inner tether-cutting reconnection, but not the external breakout reconnection. An impulsive acceleration revealed from fast separation of the H{\alpha} ribbons of the first 150 seconds suggests the CME accelerated in the inner corona, which is consistent with the temporal profile of the reconnection electric field. In conclusion, we propose a qualitative model in view of framework of a solar eruption involving, mass ejections, filament eruption, CME, and subsequent flare.Comment: 8 figures, accepted for publication in Solar Physic