118 research outputs found
MIR376A is a regulator of starvation-induced autophagy
Background: Autophagy is a vesicular trafficking process responsible for the degradation of long-lived, misfolded or abnormal proteins, as well as damaged or surplus organelles. Abnormalities of the autophagic activity may result in the accumulation of protein aggregates, organelle dysfunction, and autophagy disorders were associated with various diseases. Hence, mechanisms of autophagy regulation are under exploration.
Methods: Over-expression of hsa-miR-376a1 (shortly MIR376A) was performed to evaluate its effects on autophagy. Autophagy-related targets of the miRNA were predicted using Microcosm Targets and MIRanda bioinformatics tools and experimentally validated. Endogenous miRNA was blocked using antagomirs and the effects on target expression and autophagy were analyzed. Luciferase tests were performed to confirm that 3’ UTR sequences in target genes were functional. Differential expression of MIR376A and the related MIR376B was compared using TaqMan quantitative PCR.
Results: Here, we demonstrated that, a microRNA (miRNA) from the DlkI/Gtl2 gene cluster, MIR376A, played an important role in autophagy regulation. We showed that, amino acid and serum starvation-induced autophagy was blocked by MIR376A overexpression in MCF-7 and Huh-7 cells. MIR376A shared the same seed sequence and had overlapping targets with MIR376B, and similarly blocked the expression of key autophagy proteins ATG4C and BECN1 (Beclin 1). Indeed, 3’ UTR sequences in the mRNA of these autophagy proteins were responsive to MIR376A in luciferase assays. Antagomir tests showed that, endogenous MIR376A was participating to the control of ATG4C and BECN1 transcript and protein levels. Moreover, blockage of endogenous MIR376A accelerated starvation-induced autophagic activity. Interestingly, MIR376A and MIR376B levels were increased with different kinetics in response to starvation stress and tissue-specific level differences were also observed, pointing out to an overlapping but miRNA-specific biological role.
Conclusions: Our findings underline the importance of miRNAs encoded by the DlkI/Gtl2 gene cluster in stress-response control mechanisms, and introduce MIR376A as a new regulator of autophagy
OT Modeling: The Enterprise Beyond IT
Enterprises are composed of an enormous number of elements (e.g., organizational units, human resources, production processes, and IT systems) typically classified in the business or the IT domain. However, some crucial elements do not belong in either group: they are directly responsible for producing and delivering the company’s goods and services and include all the elements that support day to day operations. Collectively, these elements have been called operational technologies (OT) and have been conspicuously excluded from enterprise modeling (EM) approaches which traditionally have focused on the business and IT dimensions. Evidence of this is the absence of OT elements in languages and metamodels for EM. This is in line with the historical division between IT and OT in organizations that has led to information silos, independent teams, and disparate tech- nologies that only recently have started to be reconciled. Considering that OT is critical to most productive organi- zations, and the benefits that EM brings to its understand- ing and improvement, it makes sense to expand EM to include OT. For that purpose, this paper proposes an extension to ArchiMate 3.0 which includes crucial OT elements. On top of that, this paper also proposes an approach to further expand ArchiMate to address specific industries where more specific OT elements are required. This is illustrated in the paper with an extension for the Oil and Gas case that was validated with experts belonging to five companies in the sector
Quantitative analysis and comparison of 3D morphology between viable and apoptotic MCF-7 breast cancer cells and characterization of nuclear fragmentation
Morphological changes in apoptotic cells provide essential markers for defining and detection
of apoptosis as a fundamental mechanism of cell death. Among these changes, the
nuclear fragmentation and condensation have been regarded as the important markers but
quantitative characterization of these changes is yet to be achieved. We have acquired confocal
image stacks of 206 viable and apoptotic MCF-7 cells stained by three fluorescent
dyes. Three-dimensional (3D) parameters were extracted to quantify and compare their differences
in morphology. To analyze nuclear fragmentation, a new method has been developed
to determine clustering of nuclear voxels in the reconstructed cells due to fluorescence
intensity changes in nuclei of apoptotic cells. The results of these studies reveal that the 3D
morphological changes in cytoplasm and nuclear membranes in apoptotic cells provide sensitive
targets for label-free detection and staging of apoptosis. Furthermore, the clustering
analysis and morphological data on nuclear fragmentation are highly useful for derivation of
optical cell models and simulation of diffraction images to investigate light scattering by
early apoptotic cells, which can lead to future development of label-free and rapid methods
of apoptosis assay based on cell morphology.Open Access Fundin
A Review on the Mechanical Modeling of Composite Manufacturing Processes
© 2016, The Author(s). The increased usage of fiber reinforced polymer composites in load bearing applications requires a detailed understanding of the process induced residual stresses and their effect on the shape distortions. This is utmost necessary in order to have more reliable composite manufacturing since the residual stresses alter the internal stress level of the composite part during the service life and the residual shape distortions may lead to not meeting the desired geometrical tolerances. The occurrence of residual stresses during the manufacturing process inherently contains diverse interactions between the involved physical phenomena mainly related to material flow, heat transfer and polymerization or crystallization. Development of numerical process models is required for virtual design and optimization of the composite manufacturing process which avoids the expensive trial-and-error based approaches. The process models as well as applications focusing on the prediction of residual stresses and shape distortions taking place in composite manufacturing are discussed in this study. The applications on both thermoset and thermoplastic based composites are reviewed in detail
Age- and region-specific hepatitis B prevalence in Turkey estimated using generalized linear mixed models: a systematic review
Toy M, Önder FO, Wörmann T, et al. Age- and region-specific hepatitis B prevalence in Turkey estimated using generalized linear mixed models: a systematic review. BMC infectious diseases. 2011;11(1): 337.BACKGROUND: To provide a clear picture of the current hepatitis B situation, the authors performed a systematic review to estimate the age- and region-specific prevalence of chronic hepatitis B (CHB) in Turkey. METHODS: A total of 339 studies with original data on the prevalence of hepatitis B surface antigen (HBsAg) in Turkey and published between 1999 and 2009 were identified through a search of electronic databases, by reviewing citations, and by writing to authors. After a critical assessment, the authors included 129 studies, divided into categories: 'age-specific'; 'region-specific'; and 'specific population group'. To account for the differences among the studies, a generalized linear mixed model was used to estimate the overall prevalence across all age groups and regions. For specific population groups, the authors calculated the weighted mean prevalence. RESULTS: The estimated overall population prevalence was 4.57, 95% confidence interval (CI): 3.58, 5.76, and the estimated total number of CHB cases was about 3.3 million. The outcomes of the age-specific groups varied from 2.84, (95% CI: 2.60, 3.10) for the 0-14-year olds to 6.36 (95% CI: 5.83, 6.90) in the 25-34-year-old group. CONCLUSION: There are large age-group and regional differences in CHB prevalence in Turkey, where CHB remains a serious health problem
Applying the ALARA concept to the evaluation of vesicoureteric reflux
The voiding cystourethrogram (VCUG) is a widely used study to define lower urinary tract anatomy and to diagnose vesicoureteric reflux (VUR) in children. We examine the technical advances in the VCUG and other examinations for reflux that have reduced radiation exposure of children, and we give recommendations for the use of imaging studies in four groups of children: (1) children with urinary tract infection, (2) siblings of patients with VUR, (3) infants with antenatal hydronephrosis (ANH), and (4) children with a solitary functioning kidney. By performing examinations with little to no radiation, carefully selecting only the children who need imaging studies and judiciously timing follow-up examinations, we can reduce the radiation exposure of children being studied for reflux
Pressure drop of laminar gas flows in a microchannel containing various pillar matrices
Сравнение эффективности и токсичности афлиберцепта и бевацизумаба в комбинации с режимом FOLFIRI во 2‑й линии лечения пациентов с метастатическим раком толстой кишки: ретроспективный анализ многоцентрового исследования
Objective: to compare the efficacy and toxicity of aflibercept and bevacizumab in combination with fOLfIRI in secondline therapy for patients with metastatic colon cancer.Materials and methods. we performed a retrospective analysis of data on patients with metastatic colon cancer treated in 9 clinics in the Russian federation. The inclusion criteria were as follows: metastatic or locally advanced colon cancer; treatment with bevacizumab or aflibercept plus fOLfIRI in the second-line therapy. The primary outcome measure was progression-free survival (PfS). Secondary outcome measures included objective response rate and incidence of adverse events.Results. A total of 271 patients with metastatic colon cancer who received second-line therapy with bevacizumab (n = 81) or aflibercept (n = 190) between 2014 and 2018 were selected for this study. Study groups were matched for main prognostic signs. The objective response rate was 18.1 % in the bevacizumab group and 20.5 % in the aflibercept group (p = 0.7). The median PfS was 5 months (95 % confidence interval 3.8–6.1) in the aflibercept group and 7 months (95 % confidence interval 0.81–2.1) in the bevacizumab group (hazard ratio 1.4; 95 % confidence interval 0.99–2.1; p = 0.04). multivariate regression analysis demonstrated that the type of the targeted drug independently had no effect on PfS (hazard ratio 1.3; 95 % confidence interval 0.9–1.9; p = 0.2). we observed no statistically significant differences in the incidence of complications of any grades between the groups (58 % vs 72 %, p = 0.1). Patients receiving aflibercept were more likely to develop grade III–Iv arterial hypertension (2 % vs 9.5 %) and diarrhea (0 % vs 5.4 %), whereas thrombotic complications were more common in the bevacizumab group (10 % vs 1.8 %).Conclusion. we observed no significant differences in objective response rate and PfS between patients with metastatic colon cancer receiving bevacizumab or aflibercept in combination with fOLfIRI as second-line therapy. The toxicity profiles were different. Our findings can be used for choosing an optimal targeted drug for second-line treatment.Цель исследования – сравнение эффективности и токсичности афлиберцепта и бевацизумаба в комбинации с режимом fOLfIRI во 2-й линии лечения пациентов с метастатическим раком толстой кишки.Материалы и методы. Проведен ретроспективный анализ базы данных пациентов с метастатическим раком толстой кишки в рамках наблюдательного исследования работы 9 клиник РФ. Критерии включения в исследование: больные метастатическим или местно-распространенным раком толстой кишки; проведение терапии с включением бевацизумаба или афлиберцепта в комбинации с режимом fOLfIRI во 2-й линии лечения. Основной критерий эффективности – выживаемость без прогрессирования (ВбП). дополнительные критерии: частота объективных эффектов, частота развития нежелательных явлений.Результаты. Отобран 271 пациент с метастатическим раком толстой кишки, которым в 2014–2018 гг. проводилась 2-я линия терапия с включением бевацизумаба (n = 81) и афлиберцепта (n = 190). группы статически значимо не различались по основным прогностическим признакам. частота объективных эффектов составила 18,1 % в группе бевацизумаба и 20,5 % в группе афлиберцепта (р = 0,7). медиана ВбП составила 5 мес (95 % доверительный интервал 3,8–6,1) в группе афлиберцепта и 7 мес (95 % доверительный интервал 0,81–2,1) в группе бевацизумаба (отношение рисков 1,4; 95 % доверительный интервал 0,99–2,1; р = 0,04). многофакторный регрессионный анализ не подтвердил независимого влияния характера таргетного препарата на ВбП (отношение рисков 1,3; 95 % дИ 0,9–1,9; р = 0,2). Не отмечено статистически значимых различий в частоте развития осложнений всех степеней (58 % против 72 %, р = 0,1); среди негематологических осложнений артериальная гипертензия III–Iv степени (2 % против 9,5 %) и диарея (0 % против 5,4 %) чаще наблюдались в группе афлиберцепта, тромботические осложнения чаще наблюдались в группе бевацизумаба (10 % против 1,8 %).Выводы. Не отмечено статистически значимых различий между бевацизумабом и афлиберцептом в сочетании с режимом fOLfIRI во 2-й линии терапии пациентов с метастатическим раком толстой кишки ни в отношении достижения объективного эффекта, ни в отношении ВбП. Профили токсических реакций были различными. Полученные данные можно учитывать при выборе таргетного препарата во 2-й линии терапии
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