261 research outputs found

    Применение генетического алгоритма в задачах адаптации структур данных

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    Представлена разработанная схема адаптации структур данных в оперативной памяти. Для поиска адаптированной структуры данных предложено применение генетического алгоритма. Определены его особенности. Для растровых изображений с соответствующими заголовками выполнены экспериментальные исследования временной эффективности адаптированных структур данных, времени сходимости генетического алгоритма и условия целесообразности применения адаптации.Представлена розроблена схема адаптації структур даних в оперативній пам’яті. Для пошуку адаптованої структури даних запропоновано застосування генетичного алгоритму. Визначені його особливості. Для растрових зображень з відповідними заголовками виконані експериментальні дослідження часової ефективності адаптованих структур даних, часу збіжності генетичного алгоритму та умови доцільності застосування адаптації.The developed scheme of data structures adaptation in memory is given. To search for an adapted data structure, genetic algorithm is proposed and its characteristics are defined. For raster images with the appropriate headings, experimental studies of the time efficiency of adapted data structures, the convergence time of the genetic algorithm and conditions for feasibility of adapting are performed

    Loss of expression of FANCD2 protein in sporadic and hereditary breast cancer

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    Fanconi anemia (FA) is a recessive disorder associated with progressive pancytopenia, multiple developmental defects, and marked predisposition to malignancies. FA is genetically heterogeneous, comprising at least 12 complementation groups (A–M). Activation of one of the FA proteins (FANCD2) by mono-ubiquitination is an essential step in DNA damage response. As FANCD2 interacts with BRCA1, is expressed in proliferating normal breast cells, and FANCD2 knockout mice develop breast tumors, we investigated the expression of FANCD2 in sporadic and hereditary invasive breast cancer patients to evaluate its possible role in breast carcinogenesis. Two tissue microarrays of 129 and 220 sporadic breast cancers and a tissue microarray containing 25 BRCA1 germline mutation-related invasive breast cancers were stained for FANCD2. Expression results were compared with several clinicopathological variables and tested for prognostic value. Eighteen of 96 (19%) sporadic breast cancers and two of 21 (10%) BRCA1-related breast cancers were completely FANCD2-negative, which, however, still showed proliferation. In the remaining cases, the percentage of FANCD2-expressing cells correlated strongly with mitotic index and percentage of cells positive for the proliferation markers Ki-67 and Cyclin A. In immunofluorescence double staining, coexpression of FANCD2 and Ki-67 was apparent. In survival analysis, high FANCD2 expression appeared to be prognostically unfavorable for overall survival (p = 0.03), independent from other major prognosticators (p = 0.026). In conclusion, FANCD2 expression is absent in 10–20% of sporadic and BRCA1-related breast cancers, indicating that somatic inactivating (epi)genetic events in FANCD2 may be important in both sporadic and hereditary breast carcinogenesis. FANCD2 is of independent prognostic value in sporadic breast cancer

    Закономерности распределения аномальных концентраций гелия в палеозойских отложениях Донбасса

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    Підвищені концентрації гелію у вільних і розчинених газах у вугільно-породному масиві Донбасу приурочені до зон зчленування Донбасу з Приазовським і Воронезьким кристалічними масивами і Головної антикліналі. Диз'юнктивні тектонічні порушення глибокого закладення служили, ймовірно, шляхами транзиту гелію від кристалічних порід фундаменту в палеозойські відклади Донбасу, і підвищений вміст гелію може служити індикатором шляхів транзиту газів з глибоких горизонтів Донецького вугільного басейну.Elevated concentrations of helium in free and dissolved gases in coal-rock mass of the Donets Coal Basin are confined to the junction zones of the Donets Coal Basin with the Priazovie and Voronezh crystalline core-areas and Glavnaya (Principal) Anticline. Deep-laid disjunctive dislocations were probably the ways for transit of helium from crystalline basement rocks into Paleozoic deposits of the Basin. Elevated concentrations of helium can also serve as indicators of the ways for transit of gases from deep levels of the Donets Coal Basin

    Expression of hypoxia-inducible factor-1α and cell cycle proteins in invasive breast cancer are estrogen receptor related

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    BACKGROUND: The transcription factor hypoxia-inducible factor-1 (HIF-1) is a key regulator of the cellular response to hypoxia. Previous studies showed that concentrations of its subunit HIF-1α, as a surrogate for HIF-1 activity, are increased during breast carcinogenesis and can independently predict prognosis in breast cancer. During carcinogenesis, the cell cycle is progressively deregulated, and proliferation rate is a strong prognostic factor in breast cancer. In this study we undertook a detailed evaluation of the relationships between HIF-1α and cell cycle-associated proteins. METHODS: In a representative estrogen receptor (ER) group of 150 breast cancers, the expression of HIF-1α, vascular endothelial growth factor, the ER, HER-2/neu, Ki-67, cyclin A, cyclin D(1), p21, p53, and Bcl-2 was investigated by immunohistochemistry. RESULTS: High concentrations (5% or more) of HIF-1α were associated with increased proliferation as shown by positive correlations with Ki-67 (P < 0.001) and the late S–G2-phase protein cyclin A (P < 0.001), but not with the G1-phase protein cyclin D(1). High HIF-1α concentrations were also strongly associated with p53 positivity (P < 0.001) and loss of Bcl-2 expression (P = 0.013). No association was found between p21 and HIF-1α (P = 0.105) in the whole group of patients. However, the subgroup of ER-positive cancers was characterized by a strong positive association between HIF-1α and p21 (P = 0.023), and HIF-1α lacked any relation with proliferation. CONCLUSION: HIF-1α overexpression is associated with increased proliferation, which might explain the adverse prognostic impact of increased concentrations of HIF-1α in invasive breast cancer. In ER-positive tumors, HIF-1α is associated with p21 but not against proliferation. This shows the importance of further functional analysis to unravel the role of HIF-1 in late cell cycle progression, and the link between HIF-1, p21, and ER

    Adjacent thoracic lymph node metastases originating from two separate primary cancers: case report

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    Reported is an unusual case of adjacent thoracic lymph nodes demonstrating metastases from two different primary malignancies. A 51 year-old woman with a previous history of bilateral breast cancer underwent a radical gastro-oesophagectomy for adenocarcinoma of the lower third of the oesophagus. The resection specimen demonstrated breast and oesophageal metastases in adjacent thoracic lymph nodes. Mechanisms for this phenomenon, including the known local immune suppression on lymphoid cells by oesophageal carcinoma cells, are discussed

    Nanobody-targeted photodynamic therapy induces significant tumor regression of trastuzumab-resistant HER2-positive breast cancer, after a single treatment session

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    Rationale: A substantial number of breast cancer patients with an overexpression of the human epidermal growth factor receptor 2 (HER2) have residual disease after neoadjuvant therapy or become resistant to trastuzumab. Photodynamic therapy (PDT) using nanobodies targeted to HER2 is a promising treatment option for these patients. Here we investigate the in vitro and in vivo antitumor efficacy of HER2-targeted nanobody-photosensitizer (PS) conjugate PDT. Methods: Nanobodies targeting HER2 were obtained from phage display selections. Monovalent nanobodies were engineered into a biparatopic construct. The specificity of selected nanobodies was tested in immunofluorescence assays and their affinity was evaluated in binding studies, both performed in a panel of breast cancer cells varying in HER2 expression levels. The selected HER2-targeted nanobodies 1D5 and 1D5-18A12 were conjugated to the photosensitizer IRDye700DX and tested in in vitro PDT assays. Mice bearing orthotopic HCC1954 trastuzumab-resistant tumors with high HER2 expression or MCF-7 tumors with low HER2 expression were intravenously injected with nanobody-PS conjugates. Quantitative fluorescence spectroscopy was performed for the determination of the local pharmacokinetics of the fluorescence conjugates. After nanobody-PS administration, tumors were illuminated to a fluence of 100 J∙cm-2, with a fluence rate of 50 mW∙cm-2, and thereafter tumor growth was measured with a follow-up until 30 days. Results: The selected nanobodies remained functional after conjugation to the PS, binding specifically and with high affinity to HER2-positive cells. Both nanobody-PS conjugates potently and selectively induced cell death of HER2 overexpressing cells, either sensitive or resistant to trastuzumab, with low nanomolar LD50 values. In vivo, quantitative fluorescence spectroscopy showed specific accumulation of nanobody-PS conjugates in HCC1954 tumors and indicated 2 h post injection as the most suitable time point to apply light. Nanobody-targeted PDT with 1D5-PS and 1D5-18A12-PS induced significant tumor regression of trastuzumab-resistant high HER2 expressing tumors, whereas in low HER2 expressing tumors only a slight growth delay was observed. Conclusion: Nanobody-PS conjugates accumulated selectively in vivo and their fluorescence could be detected through optical imaging. Upon illumination, they selectively induced significant tumor regression of HER2 overexpressing tumors with a single treatment session. Nanobody-targeted PDT is therefore suggested as a new additional treatment for HER2-positive breast cancer, particularly of interest for trastuzumab-resistant HER2-positive breast cancer. Further studies are now needed to assess the value of this approach in c

    A conceptual approach to enhance the well-being of elderly people

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    The number of elderly people living alone is increasing. Consequently, a lot of research works have been addressing this issue in order to propose solutions that can enhance the quality of life of elderly people. Most of them have been concerned in dealing with objective issues such as forgetfulness or detecting falls. In this paper, we propose a conceptual approach of a system that intends to enhance the daily sense of user’s well-being. For that, our proposal consists in a system that works as a social network and a smartwatch application that works unobtrusively and collects the user’s physiological data. In addition, we debate how important features such as to detect user’s affective states and to potentiate user’s memory could be implemented. Our study shows that there are still some important limitations which affect the success of applications built in the context of elderly care and which are mostly related with accuracy and usability of this kind of system. However, we believe that with our approach we will be able to address some of those limitations and define a system that can enhance the well-being of elderly people and improve their cognitive capabilities.The work presented in this paper has been developed under the EUREKA - ITEA3 Project PHE (PHE-16040), and by National Funds through FCT (Fundação para a Ciência e a Tecnologia) under the projects UID/EEA/00760/2019 and UID/CEC/00319/2019 and by NORTE-01-0247-FEDER-033275 (AIRDOC - “Aplicação móvel Inteligente para suporte individualizado e monitorização da função e sons Respiratórios de Doentes Obstrutivos Crónicos ”) by NORTE 2020 (Programa Operacional Regional do Norte)
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