Liquid Nonlinear Oscillations in the U-Tube System

Dynamics of oscillation processes in a siphon U-tube is studied for the system of connected vessels filled with homogeneous liquid. The equations and phase paths describing the motion of viscous and non-viscous liquids are given, oscillation frequencies are considered. Oscillations are nonlinear in general case, but they turn into linear by setting specific parameter values of the system. Phase portraits are obtained and their dependences on parameters of the system are analyzedfor both linear and non-linear cases

Development and Validation of WECC Variable Speed Wind Turbine Dynamic Models for Grid Integration Studies

This paper describes reduced-order, simplified wind turbine models for analyzing the stability impact of large arrays of wind turbines with a single point of network interconnection

Features of the cellular and stromal-vascular component of the microenvironment of carcinoma of the larynx with different degrees of differentiation

Microenvironment of tumor is the meaningful index of the state of antitumoral immune answer and important description of tumor progression. Generally known, that a degree of embryonization (malignantness), histological type and expressed of lymphoplasmacytic infiltration of stroma of different tumors, are the objective and qualificatory tests of malignantness, along with such clinical and anatomical factors, as localization and stage of process. Depending on the degree of embryonization of cancer of larynx there are substantial distinctions in composition, quantitative correlation and localization of components of cellular infiltration in relation to a tumor. The features of 'geography* of vascular river-bed, closeness of his distribution are educed, the estimation of fibred component of microenvironment zone is conducted.Параканкрозное микроокружение опухоли является значимым показателем состояния противоопухолевого иммунного ответа и важной характеристикой опухолевой прогрессии. Общеизвестно, что степень дифференцировки опухоли, её гистологический тип и выраженность лимфоплазмоцитарной инфильтрации стромы различных опухолей являются объективными и определяющими критериями злокачественности, наряду с такими клинико-анатомическими факторами, как-локализация и стадия процесса. В зависимости от степени дифференцировки карциномы гортани наблюдаются существенные различия в составе, количественном соотношении и локализации компонентов клеточного инфильтрата по отношению к опухоли. Выявлены особенности «географии» сосудистого русла, плотности его распределения, проведена оценка волокнистого компонента параканкрозной зоны

Structural features of the process of formation of neutrophilic granulocytes networks extracellular DNA at a meeting with larynx carcinoma tumor cells

Neutrophilic granulocytesas a permanent structure in the tumor microenvironment play an ambiguous role in oncogenesis. In response to microbial and non-microbial stimuli neutrophils actively formed in the extracellular space net-like structures composed of nucleic acids and enzymes-neutrophil extracellular trap. We have observed that in tumor tissue near the larynx carcinoma tumor cells spread diffusely and clusters of extracellular DNA.Нейтрофильные гранулоциты, являясь постоянной структурой в микроокружении опухолей, играют неоднозначную роль в онкогенезе. В ответ на микробные и немикробные стимулы нейтрофилы активно формируют во внеклеточном пространстве сетеподобные структуры, состоящие из нуклеиновых кислот и ферментов - нейтрофильные внеклеточные ловушки. Нами было замечено, что в ткани опухоли карциномы гортани рядом с опухолевыми клетками диффузно и скоплениями распределяется внеклеточная ДНК

Features of the lymphocytic microenvironment in metastatic uveal melanoma

Aim of the study. Compare the lymphocytic microenvironment of primary uveal melanomas and distant metastases (to the liver).Цель исследования — сравнить лимфоцитарное микроокружение первичных увеальных меланом и отдаленных метастазов (в печень)

Role of Operon aaoSo-mutT in Antioxidant Defense in Streptococcus oligofermentans

Previously, we have found that an insertional inactivation of aaoSo, a gene encoding L-amino acid oxidase (LAAO), causes marked repression of the growth of Streptococcus oligofermentans. Here, we found that aaoSo and mutT, a homolog of pyrophosphohydrolase gene of Escherichia coli, constituted an operon. Deletion of either gene did not impair the growth of S. oligofermentans, but double deletion of both aaoSo and mutT was lethal. Quantitative PCR showed that the transcript abundance of mutT was reduced for 13-fold in the aaoSo insertional mutant, indicating that gene polarity derived from the inactivation of aaoSo attenuated the expression of mutT. Enzymatic assays were conducted to determine the biochemical functions of LAAO and MutT of S. oligofermentans. The results indicated that LAAO functioned as an aminoacetone oxidase [47.75 nmol H2O2 (min·mg protein)–1]; and MutT showed the pyrophosphohydrolase activity, which removed mutagens such as 8-oxo-dGTP. Like paraquat, aaoSo mutations increased the expression of SOD, and addition of aminoacetone (final concentration, 5 mM) decreased the mutant’s growth by 11%, indicating that the aaoSo mutants are under ROS stress. HPLC did reveal elevated levels of cytoplasmic aminoacetone in both the deletion and insertional gene mutants of aaoSo. Electron spin resonance spectroscopy showed increased hydroxyl radicals in both types of aaoSo mutant. This demonstrated that inactivation of aaoSo caused the elevation of the prooxidant aminoacetone, resulting the cellular ROS stress. Our study indicates that the presence of both LAAO and MutT can prevent endogenous metabolites-generated ROS and mutagens. In this way, we were able to determine the role of the aaoSo-mutT operon in antioxidant defense in S. oligofermentans

View on the role of neutrophiles extracellular DNA as a component of the microenvironment of tumor in the process of carcinogenesis

One of the important features of malignant neoplasms is their Autonomous growth, adjustable locally produced by factors which include the factors of «microenvironment» tumors, produced by tumor cells and cells in the stroma. Neutrophil granulocytes, being a permanent structure in the palette of the «microenvironment» tumors play a different role in oncogenes. In response to microbial and anmikrobial incentives neutrophils actively shape in the extracellular space setuptable structure consisting of nucleic acids and enzymes - neutrophil extracellular nets. It was noticed, that in the tumor tissue, breast carcinoma near the tumor cells is diffuse and clusters distributed free cell DNA.Одной из важных особенностей злокачественных новообразований является их автономный рост, регулируемый локально продуцируемыми факторами, к которым относят «факторы микроокружения» опухолей, продуцируемые как самими опухолевыми клетками, так и клетками окружающей их стромы. Нейтрофильные гранулоциты, являясь постоянной структурой в «палитре микроокружения» опухолей, играют неоднозначную роль в онкогенезе. В ответ на микробные и немикробные стимулы нейтрофилы активно формируют во внеклеточном пространстве сетеподобные структуры, состоящие из нуклеиновых кислот и ферментов - нейтрофильные внеклеточные ловушки. Нами было замечено, что в ткани опухоли карциномы молочной железы рядом с опухолевыми клетками диффузно и скоплениями распределяется внеклеточная ДНК

The process of forming autological neutrophil extracellular networks dna at a meeting with the tumor cells of breast carcinoma association with tumor grade and receptor status of a tumor

Tumor microenvironment is an important component of tumor progression. Breast cancer is currently the most common malignancy in women. Neutrophilic granulocytes, as a permanent structure in the 'palette microenvironment' tumors, play a different role in oncogenesis. The aim of the study was to compare the formation of networks of extracellular DNA autologous neutrophils in around cancer area and intratumoral areas in invasive breast carcinomas nonspecific type luminal A and luminal В type HER2 negative. With a change in the phenotype of carcinomas and malignancy of luminal A type to В type luminal determined by reducing the amount of extracellular DNA chains formed by the neutrophils as the exposed, twining and tumor cells, and preferably the latter.Микроокружение опухоли является важным компонентом опухолевой прогрессии. Рак молочной железы сегодня является самой распространенной злокачественной опухолью у женщин. Нейтрофильные гранулоциты, являясь постоянной структурой в «палитре микроокружения» опухолей, играют неоднозначную роль в онкогенезе. Целью исследования явилось сравнение образования сетей внеклеточной ДНК аутологичными нейтрофилами микроокружения в параканкрозной и интратуморальной зонах в инвазивных карциномах молочной железы неспецифического типа люминального типа А и люминального типа В HER2 негативного. С изменением злокачественности и фенотипа карциномы от люминального типа А к люминальному типу В определяется уменьшение количества внеклеточных сетей ДНК, сформированных нейтрофилами, как свободнолежащих, так и оплетающих опухолевые клетки, причем преимущественно последних

Cell cycle checkpoint status in human malignant mesothelioma cell lines: response to gamma radiation

Knowledge of the function of the cell cycle checkpoints in tumour cells may be important to develop treatment strategies for human cancers. The protein p53 is an important factor that regulates cell cycle progression and apoptosis in response to drugs. In human malignant mesothelioma, p53 is generally not mutated, but may be inactivated by SV40 early region T antigen (SV40 Tag). However, the function of p53 has not been investigated in mesothelioma cells. Here, we investigated the function of the cell cycle checkpoints in six human mesothelioma cell lines (HMCLs) by studying the cell distribution in the different phases of the cell cycle by flow cytometry, and expression of cell cycle proteins, p53, p21WAF1/CIP1 and p27KIP1. In addition, we studied p53 gene mutations and expression of SV40 Tag. After exposure to γ-radiation, HMCLs were arrested either in one or both phases of the cell cycle, demonstrating a heterogeneity in cell cycle control. G1 arrest was p21WAF1/CIP1- and p53-dependent. Lack of arrest in G1 was not related to p53 mutation or binding to SV40 Tag, except in one HMCL presenting a missense mutation at codon 248. These results may help us to understand mesothelioma and develop new treatments

Absence of mutation of the p73 gene localized at chromosome 1p36.3 in hepatocellular carcinoma

Accumulating evidence has demonstrated that aberration of the p53 tumour-suppressor gene is one of the pivotal genetic events in hepatocellular carcinogenesis. Recent reports suggest that the product of hepatitis B virus (HBV) interacts with p53 and that the hepatitis C virus (HCV) core protein reduces p53 expression. A novel p73 gene, which is related to p53, has recently been identified and mapped to chromosome 1p36.3, which is a locus of multiple tumour-suppressor genes for many cancers, including hepatocellular carcinoma (HCC) and neuroblastoma. Here, we investigated mRNA expression, allelotype and mutation of p73 in 48 HCCs obtained from untreated patients. Reverse transcriptase polymerase chain reaction (RT-PCR) revealed that p73 mRNA was expressed ubiquitously at low levels in all the tumour tissues, as well as in the adjacent normal liver tissues. The frequency of p73 loss of heterozygosity was observed in 20% of HCCs, but PCR-single strand conformation polymorphism (SSCP) analysis showed no mutations in the 48 tumours except for three types of polymorphisms. These results suggest that p73 may play a role in hepatocellular carcinogenesis in a different manner from a Knudson two-hit model. The regulatory mechanism of interaction between p73 and hepatitis viruses remains to be determined. © 1999 Cancer Research Campaig