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Colorectal cancer (CRC) is one of the leading causes of death from cancer in many countries of the world, both in men and women, and these rates are on the rise. The probability of suffering from CRC is about 4–5 % and the risk for developing CRC is associated with personal features or habits such as age, chronic disease history and lifestyle, but in most cases colorectal cancer develops as a result of the degeneration of adenomatous formations or along the jagged path. Immune dysregulation, dysbiosis, and epithelial destruction contribute to colorectal cancer carcinogenesis. The gut microbiota has a relevant role, and dysbiosis situations can induce colonic carcinogenesis through a chronic inflammation mechanism. Some of the bacteria responsible for this multiphase process include Fusobacterium spp., Bacteroides fragilis and enteropathogenic Escherichia coli. moreover, CRC is caused by mutations that target oncogenes, tumour suppressor genes and genes related to DNA repair mechanisms.Considering that the average time for the development of adenocarcinoma from precancer takes about 10 years, changes in the microbiota can be a prospective marker for screening precancerous conditions of the colon, as well as the detection of changes in DNA.The work will discuss the relationship between changes in the microbial composition of the colon with the genetic mutations identified by molecular genetic sequencing.

Introduction: local treatment of metastases is an integral part of colon cancer treatment. However, there is not enough data on the efficacy of surgical resection of metastases in patients with a BRAF gene mutation to recom‑mend this approach in routine practice. We initiated a retrospective multicenter study to assess the incidence of BRAF gene mutations in patients with metastatic colon cancer and to study the efficacy of metastasectomy in this group of patients.Materials and methods: we selected all patients who underwent surgical resection of metastases in various sites from the database of patients with BRAF gene mutations created as a result of a multicenter retrospective study with participation of 7 clinics in the Russian Federation. All 57 patients with RAS gene mutations and 43 patients with wild‑type RAS and BRAF genes who also underwent surgical resection of metastases at any stage of treatment were selected from the register of the Chemotherapy Department No. 2 of the NMRC of Oncology named after N. N. Blokhin for comparative analysis. Disease‑free survival and overall survival were used as primary efficacy criteria.Results: we found 26 patients with BRAF gene mutations who underwent surgical resection of metastases. When comparing disease‑free survival, the worst median was achieved in the group of patients with BRAF gene mutations: 7 months versus 14 months in patients with RAS gene mutations (HR 0.4, 94 % CI 0.23–0.7, P = 0.006); median disease‑free survival was not achieved in the wild‑type RAS and BRAF group (HR 0.2, 95 % CI 0.11–0.45, P The median overall survival in the BRAF gene mutation group was 26 months versus 38 months in the RAS gene mutations group (HR 0.8, 95 % CI 0.33–1.98, P = 0.6) and 49 months in the wtRAS/wtBRAF group (RR 0.46, 95 % CI 0.17–1.24, P = 0.1). Resection of recurrent tumors in patients with metastases in retroperitoneal lymph nodes was associated with extremely low disease‑free survival (2 months); at the same time, disease‑free survival was 7 months after resection of isolated metastases in the liver and 8 months for metastases in the peritoneum.Conclusion: prognosis of patients with a BRAF gene mutation after surgical resection of metastases is worse than in patients with a different mutation phenotype. Nevertheless, literature data, as well as the results of our study, confirm the possibility of performing metastasectomy with careful selection of patients.

Gastrointestinal stromal tumors (GIST) are the most common type of mesenchymal malignancies of the gastrointestinal (GI) tract. Almost 10% of them are originated outside of the GI tract (extra-GIST), while GIST of the greater omentum constitutes about 1% among stromal tumors. More than 80% of GIST have mutations in c-KIT and PDGFRA genes. Herein we demonstrate the case of successful treatment of patient with giant omental GIST with c-KIT exon 11 mutation. 64-years-old woman, was admitted to the Department of abdominal oncology with complaints of shortness of breath and abdominal enlargement in volume. CT-scan revealed a large tumor in the abdominal cavity with tumor size of 543422 cm. The patient underwent left thoraco-abdominal approach. It was found that the tumor was originated from the greater omentum with several metastases located on the peritoneum of the left lateral channel. Resection of the large omentum, splenectomy, liver resection and was done. Postoperative immunohistochemical study showed the expression of CD117, CD34 in tumor cells. Ki-67 index was 1215%. Genetic study revealed c-KIT exon 11 mutation. Treatment with imatinib 400 mg per day was started. Patient has been treated with imatinib for 12 years. On control examination we have found a metastasis in the anterior abdominal wall 3,532,5 cm in diameter. Afterwards we performed resection of anterior abdominal wall with metastasis on 9 November 2017. Immunohistochemical study confirmed metastasis of GIST. The index of tumor proliferation activity (Ki-67) was 45%. Patient prolonged imatinib treatment at the dose of 400 mg per day after operation. No signs of progression have been revealed on control examination 72 months after the operation. 12-year progression-free survival during imatinib treatment is unique in our practice. Moreover, in the case of further progression, we have second and third-line targeted therapy (sunitinib and regorafenib) and surgery treatment in local progression.

—We present the results of the laboratory studies on fluid initiated fracture in the samples of porous-fractured rocks that have been initially saturated with a pressure-injected fluid and then tested under increasing fluid pressure in saturated rocks. The tests were conducted at the Geophysical observatory “Borok” of Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences. The laboratory is equipped with electrohydraulic press INOVA-1000. The experiments were conducted on the rock samples with substantially different porosity. The tested samples were made of Buffalo sandstones, granites from the well drilled in a seismically active region and of granites from the well in the Voronezh crystalline massif. The permeability of granite samples was varied by their controlled artificial cracking by successive heating and cooling. The experimental procedure was set up in the following way. A preliminarily dried sample was initially subjected to uniaxial loading in uniform compression (confining pressure). Loading was performed at a constant strain rate until the moment when the growth rate of acoustic emission (AE) activity began to accelerate which indicated that the stress level approaches ultimate strength. Since that, the loading rate was decreased by an order of magnitude, and water was infused into a sample from its top face. The bottom end of a sample was tightly sealed and impermeable to water. After this, the pore pressure in the sample that had got saturated with water to that moment was raised in steps whose amplitudes were varied. The obtained results of the laboratory studies show that the character and intensity of fluid initiation of fracture markedly differ under primary fluid injection into the porous-fractured samples and under the subsequent increases of the pore pressure in the saturated samples. The time delay of acoustic response relative to fluid initiation and the amplitude of the response proved to be larger in the case of water injection into dry samples than in the case of raising the pore pressure in saturated samples. The AE response to the decrease in the pore pressure was also detected in the experiments. The theoretical analysis of fluid propagation in a pore space of an air-filled sample in the model with piston-type air displacement has shown that in the case of water injection into a dry sample, the fluid pressure front propagates more slowly than in the saturated sample.

Objective. To assess the influence of the extent of sclerosing component in the retroperitoneal well-differentiated liposarcoma (WDLPS) on the survival. Material and methods. The retrospective study included 111 patients with primary retroperitoneal WLPS who underwent radical surgical treatment in Federal State Budgetary Institution N.N. Blokhin National Medical Research Center of Oncology. Histological slides of all surgical specimens were reviewed by experienced pathologist and reclassified according to criteria of WHO (2013). Patients were divided into groups depending on the extent of the sclerosing component in the tumor and enrolled in intergroup analysis. We analyzed relationship between extent of the sclerosing component in the tumor and frequency of the pathologically confirmed visceral invasion. Also, we have analyzed the influence of the visceral invasion of WDLPS on the long-term results overall (OS) and recurrence-free (RFS) survival. Results. Pathologically confirmed visceral invasion was revealed in 17% of cases with the sclerosing component less 20%, and in 31% of cases with the sclerosing component more 20%. OS was significantly worse in the group of patients who suffered from WDLPS with visceral invasion than in the group of patients without visceral invasion (p = 0.009; logarithmic criterion). The median OS in the compared groups was 85 (95% CI, 84, 87) and 142 (95% CI, 109, 175) months, the 5-year OS rate was 41% and 86%, respectively. RFS was significantly worse in the group of patients with histologically confirmed visceral invasion than in the group without organ invasion (p = 0.001; logarithmic criterion). Median RFS in the compared groups was 26 (95% CI, 20, 32) and 57 (95% CI, 38, 76) months, 2-year RFS 33% and 85%, respectively. Conclusion. Results of the study demonstrate more aggressive behavior of WDLPS with increasing extent of the sclerosing component. We believe that semi-quantitative counting of sclerosing component in retroperitoneal WDLPS can serve as an effective morphological marker of a less favorable prognosis of the disease.

Laboratory experiments on studying the aftershock regime are carried out with sandstone specimens under different axial loading and uniform compression and constant pore pressure. The aftershock sequences are modeled by the scenario of stepwise increasing axial loading of a specimen with strain control ensuring regular generation of aftershock sequences. The experiments are conducted on intact specimens and on the specimens with preliminarily formed shear macrofractures simulating natural faults. The experiments were conducted with multichannel recording of the acoustic emission (AE) signals which made it possible to locate the AE sources. Several types of the dependence of the acoustic activity relaxation parameters (parameters p and c of the modified Omori law and the Gutenberg–Richter b-value) on the level of acting stresses are revealed. The b-value decreases with the growth of axial stresses at all levels of uniform compression. In the case of fracture on the preexisting fault, the Omori relaxation parameter p increases with the growth of axial stresses whereas parameter c (the time delay before the onset of relaxation) decreases with the growth of axial stresses and increases with the rise of the level of uniform compression. In the case of a fracture of an undamaged specimen, parameter p remains unchanged as the axial stresses grow, whereas parameter c increases slightly. Parameter variations in the case of a complex stress state with both varying deviatoric (differential stresses) and spherical parts (effective pressure) of the stress tensor take on a unified form when expressed in terms of Coulomb stresses. It is hypothesized that the time delay of the aftershock activity relaxation is determined by the kinetics of fracture in accordance with the kinetic concept of strength in solids. This hypothesis is supported by exponential dependence of parameter c on stresses and on the effective strength of the medium revealed in the experiments. Under this hypothesis, the dependences of parameter c on the Coulomb stresses can be unified for different effective strength values with the use of Zhurkov’s formula for durability of materials. The obtained parameter estimates for the dependence of c on strength and stresses suggest that the c value is determined by the difference of the strength and the acting stresses, indicating how far the stress state of the medium is from the critical state corresponding to the ultimate strength.

To evaluate the impact of malignancy grade and the proportion of the dedifferentiated component (DC) in retroperitoneal dedifferentiated liposarcomas (DDLS) on the course and prognosis of the disease.The retrospective study enrolled 74 patients with primary retroperitoneal DDLS who underwent radical surgical treatment in the N.N. Blokhin National Medical Research Center of Oncology, Ministry of Health of Russia. Histological surgery specimens from all cases of DDLS were reexamined and reclassified. According to malignancy grades and the proportion of the dedifferentiated component in the tumor, the patients were divided into the comparison groups included in the intergroup analysis of overall and relapse-free survival (OS and RFS) rates. The authors also analyzed the relationship between the proportion of the dedifferentiated component in DDLS and the frequency of adjacent organ invasion.Patients with a more than 15% dedifferentiated component had significantly lower OS rates than those with a less than 15% one (This investigation suggests that DDLS have a more aggressive course with an increasing proportion of the dedifferentiated component in the tumor. Considering the histological variability in the dedifferentiated component, which is demonstrated in the research and scientific literature, as well as lack of a prognostic impact of histological grade, the authors believe that semi-quantitative assessment of the proportion of the dedifferentiated component in DDLS is able to serve as a simple and efficient morphological marker for the course of the disease and prognosis in retroperitoneal DDLS.Оценка влияния степени злокачественности и доли дедифференцированного компонента в забрюшинных дедифференцированных липосаркомах (ДДЛПС) на течение и прогноз заболевания.В ретроспективное исследование включены 74 пациента с первичными забрюшинными ДДЛПС, которым было произведено радикальное хирургическое лечение в ФГБУ «НМИЦ онкологии им. Н.Н. Блохина» Минздрава России. Выполнены пересмотр и реклассификация гистологических препаратов операционного материала всех случаев ДДЛПС. В зависимости от степени злокачественности и доли дедифференцированного компонента в опухоли больные были разделены на группы сравнения, включенные в межгрупповой анализ общей (ОВ) и безрецидивной (БРВ) выживаемости. Также проанализирована взаимосвязь величины доли дедифференцированного компонента в ДДЛПС и частоты инвазии прилежащих органов.В группе больных с долей дедифференцированного компонента более 15% ОВ была достоверно хуже, чем в группе пациентов с долей такового менее 15% (Заключение. Настоящее исследование свидетельствует о более агрессивном течении ДДЛПС при нарастании доли дедифференцированного компонента в опухоли. Учитывая гистологическую вариабельность дедифференцированного компонента, продемонстрированную в исследовании и научной литературе, а также отсутствие влияния степени злокачественности на прогноз, полагаем, что полуколичественная оценка доли дедифференцированного компонента в ДДЛПС способна служить простым и эффективным морфологическим маркером течения заболевания и прогноза при забрюшинных ДДЛПС.

Laboratory experiments on studying the aftershock regime are carried out on sandstone specimens at different levels of axial loading and uniform compression and at constant pore pressure. The aftershock sequences are modeled by the scenario of stepwise increasing axial loading of a specimen with strain control, which ensures the regular generation of aftershock sequences. The experiments are conducted on intact specimens and on those with preliminarily formed shear macrofractures simulating natural faults. The multichannel recording of the signals of acoustic emission (AE) during the experiments allowed locating the AE sources. Several types of the dependence of the parameters of relaxation of the acoustic activity—parameters p and c of the modified Omori law and the Gutenberg–Richter b-value—on the level of acting stresses are revealed. The b-value decreases with the growth of axial stresses at all levels of uniform compression. In the case of a fracture on the preexisting fault, the Omori relaxation parameter p increases with the growth of axial stresses; parameter c—the time delay before the onset of relaxation—decreases with the growth of axial stresses and increases with the rise of the level of uniform compression. In the case of a fracture of an undamaged specimen, parameter p remains unchanged with the growth of axial stresses, whereas parameter c increases slightly. Parameter variations in the case of a complex stress state with both varying deviatoric (differential stresses) and spherical parts (effective pressure) of the stress tensor take on a unified form when expressed in terms of Coulomb stresses. It is hypothesized that the time delay of the relaxation of the aftershock activity is determined by the kinetics of a fracture in accordance with the kinetic concept of strength in solids. This hypothesis is supported by the exponential dependences of parameter c on stresses and the effective strength of the medium which are revealed in the experiments. Under this hypothesis, based on Zhurkov’s formula for the durability of materials, it is possible to unify the dependences of parameter c on the Coulomb stresses at different effective strength values. The obtained parameter estimates for the dependence of c on strength and stresses suggest that the c value is determined by the difference of the strength and the acting stresses, thus indicating how far the stress state of the medium is from critically corresponding to the ultimate strength.

Based on the earthquake catalog data for the Koyna–Warna region of induced seismicity in western India, the seasonal variations in seismic activity associated with annual fluctuations in the reservoir water level are analyzed over the time span of the entire history of seismological observations in this region. The regularities in the time changes in the structure of seasonal variations are revealed. The seasonal seismic activity is minimal in May–June when the reservoir level is lowest. During the remaining part of the year, the activity has three peaks: the fall peak in September, winter peak in November–December, and spring peak in February–March. The first mentioned peak, which falls in the phase of the water level reaching its maximal seasonal value is considered as the immediate response of the fluid saturated medium to the additional loading under the weight of reservoir water. The two subsequent maxima concur with the decline phase in the reservoir level and are interpreted as the delayed response associated with the changes in the properties of the medium due to water diffusion. It is shown that the intensities of the immediate and delayed responses to the seasonal water level variations both vary with time as does their ratio. The probable factors affecting the variations in the intensity of the seasonal components of the reservoir-induced seismicity are discussed.

Scanning for mutations by DNA melting analysis (DMA) is based on asymmetric PCR followed by the melting of duplexes formed by single-stranded amplicons with TaqMan probes. The method is optimally suited for clinical genetic testing; it is easy to perform, high-throughput, and sensitive. The detection limit of mutant alleles by the DMA method is about 3%, which is much higher than the sensitivity of Sanger sequencing. In addition, the DMA method is realized in a closed-tube format, while 2-h assay is carried out in a single tube without any intermediate or additional procedures thereby minimizing the risk of cross contamination of the samples. The validation of the DMA method was performed by scanning for mutations of clinically significant genes KRAS, NRAS, BRAF, and PIK3CA in 324 DNA samples from tumors of patients with melanoma, colorectal and lung cancer. DNA was isolated either directly from tumor tissues, or from formalin- fixed paraffin-embedded tumor tissues. The detected mutations were verified by Sanger sequencing. The spectra of mutations identified in each tumor type correspond to the literature data and, thus, validate the use of DMA.

A rock behavior experiment with uniaxial compression revealed the effect of acoustic activity in loaded fluid-saturated Berea sandstone samples in response to an electric current. It is established that it is substantially intensified in periods of the current impact and decreases after its cut-off. The current impact also results in a growth of radial deformation indicating an increase in the sample volume. The effect of acoustic activation increases in response to increased heat emitted by the electric current during its flow through the sample, which allows the discovered effect to be explained by initiation of its destruction due to thermal expansion of the fluid in rock interstices and fissures.

Background. At the present time results of some pediatric protocols (FAB/LMB96 with and without rituximab, B-NHL-BFM90/95, B-NHL-2004m) were published but prognostic and diagnostic significance of markers, such as: C-MYC, STAT3, pSTAT3, TRAF1 expression, C-MYC gene rearrangement and amplification in childhood large B-cell lymphomas with mediastinum involvement is unknown. In this article there were presented results of treatment childhood large B-cell lymphomas with mediastinum involvement according to protocols IDM-NHL-BFM90, B-NHL-BFM 95 ± rituximab in view of morpho-immunological tumor’s features.Design/Methods. From 1994 to 2015 twenty two pediatric patients with large B-cell lymphomas with mediastinum involvement were included in trials IDM-NHL-BFM90, B-NHL-BFM 95 ± rituximab. Male/female ratio was 1/2. Median age - 12.2±0.6 years (range from 5 till 18). Median of age was 13.5 years. Stage III-IV, R3-R4 risk groups were revealed in all patients (100%). GCB/non-GCB DLBCL subtypes were assessed by Hans and Visco-Young immunohistochemical algorithms. Cutoff values of 40% for MYC, 70% for BCL2, 20% for STAT3, 50% for pSTAT3tyr705, TRAF1, TNFAIP2 were established. MYC gene rearrangement and amplification were assessed by FISH using locus-specific MYC (8q24) tricolor breakapart probe and MYC (8q24) SE8 control probe.Results. According to the data of this clinical trial there were revealed distinctive features of molecular portrait childhood primary mediastinal (thymic) large B-cell lymphoma that include: CD20 expression in all patients, high frequency of CD23, CD30, C-MYC, PAX5, TRAF1, TNFAIP2 expression, absence of CD10, pSTAT3tyr705 expression, low frequency of IgM expression, absence of C- MYC gene rearrangement and/or amplification despite the level of C-MYC expression more 70%, high activity of JAK2-JMJD2C epigenetic regulation of pSTAT3tyr705 independent C-MYC expression. There is the tendency to the formation of molecular portrait of childhood diffuse large B-cell lymphoma with mediastinum involvement: CD20 expression in all patients, non-GCB variant, high frequency of C-MYC expression, C-MYC gene rearrangement, absence of CD23, TRAF1, TNFAIP2 expression, low frequency of CD30 expression.Using protocol B-NHL-BFM 95 plus rituximab we have achieved high level of relapse-free survival in patients with large B-cell lymphomas with mediastinum involvement. There is not revealed any influence of investigated markers (CD23, CD30, C-MYC) on overall survival, event-free survival and relapse-free survival.Conclusion. Number of patients in this study is not enough to estimate authentic prognostic significance of these markers but high-intensive B-NHL-BFM95 + rituximab chemotherapy showed good therapeutic effect in our patients. This study will be continued.

This review provides information on the definition of febrile seizures in children, presents modern data on the dependence of the genetic predisposition to IL-Ιβ gene mutations and development of febrile seizures in children. Purpose of the review is analysis of available publications devoted to the study of the role of IL-Ιβ polymorphism in the development of febrile seizures in children. The literature search included available full-text publications in Russian and English databases. It was found that febrile seizures are characteristic for children from 6 months to 3 years. The causes of seizures still serve as a subject of debate. Family history of febrile seizures in the development is most important risk factor. Positive family history can be detected in 25-40% of patients. Components of the immune response may play a role in the pathogenesis of febrile seizures. One factor is a pro-inflammatory cytokine gene polymorphism of interleukin-ΐβ (IL-Ιβ). The analysis of the literature demonstrates the need for a detailed study of the genetic causes of febrile seizures in children, especially in patients with a positive family history.

The paper describes a clinical case of the rare tumor renal cell carcinoma associated with Xp11 translocations involving the TFE3 gene in a 53-year-old male patient. It provides the detailed characteristics of current diagnostic techniques.Представлено описание клинического случая редкой опухоли - почечно-клеточного рака, ассоциированного с Хр11-транслокацией гена TFE3 у пациента 53 лет. Дана развернутая характеристика современных методов диагностики.

A functional diagram of the inventory of land reclamation networks in St. Petersburg is proposed. Its main element is geo-information systems of visualization of geo-data, filled in on the basis of cartographic materials, topographic tablets, the results of satellite imagery and aerial photography, the results of field surveys of open and closed land reclamation systems. The advantage of the proposed approach is to reduce the laboriousness of work on the inventory of ameliorative network, the definition of its functional purpose and technical condition. The results of the inventory are presented in a single geo-information complex, which allows online access to any cartographic and attribute data.

The high resolution melting analysis (HRMA) is a new highly efficient method for genotyping and mutation scanning. HRMA is conducted immediately after PCR in closed-tube format, which enables the high throughput of the method. However, the closed-tube format makes HRMA dependent on the conditions of PCR and, thus, limits its capabilities. The open-tube format, which we have already developed (postamplification shortening of amplicons and optimized composition of ion medium), is applicable to the scanning of mutations of the K-RAS oncogene in tumor tissue and formalin-fixed paraffin-embedded samples. It is found that the open-tube format of DNA melting significantly increases the sensitivity of finding mutant alleles when using instruments both with and without an HRMA module. The higher sensitivity of the DNA melting compared to “Sanger” sequencing allows one to decrease the number of false-negative results of the mutation test, which is highly important for some forms of cancer.

Scanning for mutations by DNA melting analysis (DMA) is based on asymmetric PCR followed by the melting of duplexes formed by single-stranded amplicons with TaqMan probes. The method is optimally suited for clinical genetic testing; it is easy to perform, high-throughput, and sensitive. The detection limit of mutant alleles by the DMA method is about 3%, which is much higher than the sensitivity of Sanger sequencing. In addition, the DMA method is realized in a closed-tube format, while 2-h assay is carried out in a single tube without any intermediate or additional procedures thereby minimizing the risk of cross contamination of the samples. The validation of the DMA method was performed by scanning for mutations of clinically significant genes KRAS, NRAS, BRAF, and PIK3CA in 324 DNA samples from tumors of patients with melanoma, colorectal and lung cancer. DNA was isolated either directly from tumor tissues, or from formalin-fixed paraffin-embedded tumor tissues. The detected mutations were verified by Sanger sequencing. The spectra of mutations identified in each tumor type correspond to the literature data and, thus, validate the use of DMA.

High resolution melting analysis (HRMA) using special "saturating" fluorescent dyes is a new and very effective approach to genotyping and mutation scanning. HRMA, which is carried out usually just after PCR without any intermediate manipulations (the "closed tube" format), is simple and high-throughput method excluding sample cross-contaminations. The "closed tube" format makes, however, HRMA dependent on PCR mixes and, as such, limits its capability. The "open tube" format (post-PCR amplicon shortening and optimization of the ionic medium) proposed by us earlier, although somewhat more laborious, significantly increases sensitivity of the method and makes it possible to scan mutations in the short amplicons using conventional SYBR Green I dye and a standard (not adapted specifically for HRMA) real-time PCR instrument. Detection of mutant K-RAS in DNA of clinical specimens (tumor tissues, formalin-fixed paraffin-embedded samples) reveals equal, at least, sensitivity of this method as compared with the HRMA and much higher as compared with Sanger sequencing. The problem of false-negative results in mutation scanning of K-RAS, which is highly important in some forms of cancer, is discussed.

The paper gives the results of investigating the cultured tissues from patients with breast cancer (BC) and those with neuroblastoma, by applying both the traditional studies and molecular genetic techniques (FISH). The cultures from the patients with neuroblastoma represented as three cell types--N, S, and I. There are certain similarities between the cell composition in the culture medium and the histological structure of the tumor. Mature neoplasms of the ganglioneuroma type contain S-type cells only while intermediate type I cells are a predominant element of immature neuroblastomas. The presence of a considerable number of I cells in the explants appears to suggest a poor prognosis even when the tumor has a comparatively mature structure as a whole. The results of FISH on explant cells presented a means of detecting a broad range of points that are not recorded on histologic specimens--amplification on the metaphase plate, localization of an amplified product, amplification on one chromosome, and double acentric chromosomes. The results of cultivation of BC cells are difficult to systematize although they offer the advantage of performing the FISH reaction. The authors recommend that the tissue culture method should be more extensively used in the day-to-day diagnostic work of pathology laboratories.

Twenty samples of benign pigmented neoplasms of the skin, including 9 intradermal nevi and 11 complex ones, were investigated. Fluorescence in situ hybridization was used to detect the copy number of the RREB1 (6p25), MYB (6q23), and CCND1 (11q13) genes. Analysis of the findings revealed no significant changes characteristic of melanoma in the nevi. However, the authors established that there was a direct correlation between the copy number of the MYB and RREB1 genes and that the amount of the MYB gene most frequently deviated from the normal values. In addition, a relationship was found between the number of MYB gene copies and the depth of the epidermal layer. In cases of an intradermal nevus, the copy numbers of the CCND1 and MYB genes were shown to vary more greatly than in cases of a complex nevus.

Spatial and temporal patterns of acoustic emission (AE) were studied. A pre-fractured cylinder of granite was loaded in a triaxial machine at 160 MPa confining pressure until stick-slip events occurred. The experiments were conducted at a constant strain rate of 10−7 s−1 that was modulated by small-amplitude sinusoidal oscillations with periods of 175 and 570 seconds. Amplitude of the oscillations was a few percent of the total load and was intended to simulate periodic loading observed in nature (e.g., earth tides or other sources). An ultrasonic acquisition system with 13 piezosensors recorded acoustic emissions that were generated during deformation of the sample. We observed a correlation between AE response and sinusoidal loading. The effect was more pronounced for higher frequency of the modulating force. A time-space spectral analysis for a “point” process was used to investigate details of the periodic AE components. The main result of the study was the correlation of oscillations of acoustic activity synchronized with the applied oscillating load. The intensity of the correlated AE activity was most pronounced in the “aftershock” sequences that followed large-amplitude AE events. We suggest that this is due to the higher strain-sensitivity of the failure area when the sample is in a transient, unstable mode. We also found that the synchronization of AE activity with the oscillating external load nearly disappeared in the period immediately after the stick-slip events and gradually recovered with further loading.

The paper presents preliminary results of a study of the diagnosis of urinary bladder cancer by fluorescence in situ hybridization (FISH). Specific chromosomal aberrations are shown to be detectable in both proper tumor tissue and urine from patients with urinary bladder cancer; and the pattern of these changes coincides. FISH may identify cells with genetic disorders in urine long before the clinical symptoms of a recurrence occur.

In the solution of problems of submillimeter astronomy it often becomes necessary to record signals from a broad spectrum using a nonselective radiometric apparatus whose receivers are also broad-band. At the same time it is always desirable to obtain information on the spectral composition of the radiation received. Obviously the problem of spectral analysis can be solved in this case by placing in front of the receiver changeable, relatively narrowband elements (band-pass filters) which transmit radiation in different sections of the selected range.

Determination of the level of tetanus immunity in different age groups of a population is important in relation to the results of mass immunization of the population with vaccines containing tetanus toxoid.In this study, the level of tetanus antitoxin in sera from 1053 inhabitants of 6 villages in Bosnia and Herzegovina was determined by means of the passive haemagglutination test. The results show that children from 1 to 14 years of age regularly immunized with DT and DTP vaccines possessed a high level of immunity against tetanus (geometric mean antitoxin titre/=0.8 IU/ml) and were protected against tetanus in 80-95% of cases. The adult inhabitants (men and women over 29 years of age) were not sufficiently protected against tetanus, the concentrations of antitoxin in their sera being equal to or greater than 0.01 IU/ml in less than 50% of cases.