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  1. Article ; Online: Logical Reduction of Biological Networks to Their Most Determinative Components.

    Matache, Mihaela T / Matache, Valentin

    Bulletin of mathematical biology

    2016  Volume 78, Issue 7, Page(s) 1520–1545

    Abstract: Boolean networks have been widely used as models for gene regulatory networks, signal transduction networks, or neural networks, among many others. One of the main difficulties in analyzing the dynamics of a Boolean network and its sensitivity to ... ...

    Abstract Boolean networks have been widely used as models for gene regulatory networks, signal transduction networks, or neural networks, among many others. One of the main difficulties in analyzing the dynamics of a Boolean network and its sensitivity to perturbations or mutations is the fact that it grows exponentially with the number of nodes. Therefore, various approaches for simplifying the computations and reducing the network to a subset of relevant nodes have been proposed in the past few years. We consider a recently introduced method for reducing a Boolean network to its most determinative nodes that yield the highest information gain. The determinative power of a node is obtained by a summation of all mutual information quantities over all nodes having the chosen node as a common input, thus representing a measure of information gain obtained by the knowledge of the node under consideration. The determinative power of nodes has been considered in the literature under the assumption that the inputs are independent in which case one can use the Bahadur orthonormal basis. In this article, we relax that assumption and use a standard orthonormal basis instead. We use techniques of Hilbert space operators and harmonic analysis to generate formulas for the sensitivity to perturbations of nodes, quantified by the notions of influence, average sensitivity, and strength. Since we work on finite-dimensional spaces, our formulas and estimates can be and are formulated in plain matrix algebra terminology. We analyze the determinative power of nodes for a Boolean model of a signal transduction network of a generic fibroblast cell. We also show the similarities and differences induced by the alternative complete orthonormal basis used. Among the similarities, we mention the fact that the knowledge of the states of the most determinative nodes reduces the entropy or uncertainty of the overall network significantly. In a special case, we obtain a stronger result than in previous works, showing that a large information gain from a set of input nodes generates increased sensitivity to perturbations of those inputs.
    MeSH term(s) Animals ; Computer Simulation ; Fibroblasts/metabolism ; Gene Regulatory Networks ; Humans ; Information Theory ; Mathematical Concepts ; Models, Biological ; Neural Networks, Computer ; Signal Transduction ; Systems Biology
    Language English
    Publishing date 2016-07-14
    Publishing country United States
    Document type Journal Article
    ZDB-ID 184905-0
    ISSN 1522-9602 ; 0007-4985 ; 0092-8240
    ISSN (online) 1522-9602
    ISSN 0007-4985 ; 0092-8240
    DOI 10.1007/s11538-016-0193-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Liquid embolic agents for middle meningeal artery embolization in chronic subdural hematoma: Institutional experience with systematic review and meta-analysis.

    Sioutas, Georgios S / Vivanco-Suarez, Juan / Shekhtman, Oleg / Matache, Irina-Mihaela / Salem, Mohamed M / Burkhardt, Jan-Karl / Srinivasan, Visish M / Jankowitz, Brian T

    Interventional neuroradiology : journal of peritherapeutic neuroradiology, surgical procedures and related neurosciences

    2023  , Page(s) 15910199231183132

    Abstract: Introduction: Chronic subdural hematoma (CSDH) is associated with high recurrence rates. Middle meningeal artery embolization (MMAE) has emerged as a promising treatment option. In this systematic review and meta-analysis, we aimed to assess the safety ... ...

    Abstract Introduction: Chronic subdural hematoma (CSDH) is associated with high recurrence rates. Middle meningeal artery embolization (MMAE) has emerged as a promising treatment option. In this systematic review and meta-analysis, we aimed to assess the safety and efficacy of MMAE for CSDH using liquid embolic agents and compare them with particles.
    Methods: We systematically reviewed all studies describing MMAE for CSDH with liquid embolic agents, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Additionally, we included a cohort of patients from our institution using liquid and particle embolic agents. Data were analyzed using random-effects proportions and comparisons meta-analysis, and statistical heterogeneity was assessed.
    Results: A total of 18 studies with 507 cases of MMAE with liquid embolic agents (including our institutional experience) were included in the analysis. The success rate was 99% (95% confidence interval [CI]: 98-⁠100%), all complications rate was 1% (95% CI: 0-⁠5%), major complications rate was 0% (95% CI: 0-⁠0%), and mortality rate was 1% (95% CI: 0-⁠6%). The rate of hematoma size reduction was 97% (95% CI: 73-⁠100%), complete resolution 64% (95% CI: 33-⁠87%), radiographic recurrence 3% (95% CI: 1-⁠7%), and reoperation 3% (95% CI: 1-⁠7%). No significant differences in outcomes were found between liquid and particle embolic agents. Sensitivity analyses revealed that liquid embolic agents were associated with lower reoperation rates in upfront MMAE (risk ratio 0.13, 95% CI: 0.02-⁠0.95).
    Conclusion: MMAE with liquid embolic agents is safe and effective for the treatment of CSDH. Outcomes are comparable to particles, but liquids were associated with a decreased risk of reoperation in upfront MMAE. However, further studies are needed to support our findings.
    Language English
    Publishing date 2023-06-15
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 1354913-3
    ISSN 2385-2011 ; 1591-0199 ; 1123-9344
    ISSN (online) 2385-2011
    ISSN 1591-0199 ; 1123-9344
    DOI 10.1177/15910199231183132
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Intraoperative angiography during neurosurgical procedures on patients in prone, three-quarters prone, and park-bench positions: tertiary single-center experience with systematic review and meta-analysis.

    Vivanco-Suarez, Juan / Sioutas, Georgios S / Matache, Irina-Mihaela / Muhammad, Najib / Salem, Mohamed M / Kandregula, Sandeep / Jankowitz, Brian T / Burkhardt, Jan-Karl / Srinivasan, Visish M

    Journal of neurointerventional surgery

    2023  Volume 15, Issue 8, Page(s) 793–800

    Abstract: Background: There is limited evidence about the role and effectiveness of intraoperative angiography (IOA) during neurosurgical procedures with patients in prone, three-quarters prone, and park-bench positions.: Objective: To carry out a systematic ... ...

    Abstract Background: There is limited evidence about the role and effectiveness of intraoperative angiography (IOA) during neurosurgical procedures with patients in prone, three-quarters prone, and park-bench positions.
    Objective: To carry out a systematic review and meta-analysis of the literature to evaluate the safety and efficacy of IOA during neurosurgical procedures.
    Methods: We reviewed (between January 1960 and July 2022) all studies in which IOAs were performed during neurosurgical procedures with patients in either prone, three-quarters prone, or park-bench positions. Additionally, a cohort of patients from our institutional experience was included. Efficacy outcomes were the rate of successful angiography and the rate of surgical adjustment/revision after IOA. Safety outcomes were the rate of angiography-related complications and mortality. Data were analyzed using a random-effects meta-analysis of proportions, and statistical heterogeneity was assessed.
    Results: A total of 26 studies with 142 patients plus 32 subjects from our institution were included in the analysis. The rate of successful intraoperative angiography was 98% (95% CI 94% to 99%; I
    Conclusion: We found that IOA performed with patients in prone, three-quarters prone, and park-bench positions is feasible and safe with a non-negligible rate of intraoperative post-angiographical surgical adjustment/revision. Our findings suggest that the performance of IOA to complement vascular neurosurgical procedures might have a valuable role in favoring patient outcomes.
    MeSH term(s) Humans ; Angiography ; Neurosurgical Procedures/adverse effects ; Neurosurgical Procedures/methods ; Monitoring, Intraoperative/methods
    Language English
    Publishing date 2023-04-17
    Publishing country England
    Document type Meta-Analysis ; Systematic Review ; Journal Article
    ZDB-ID 2514982-9
    ISSN 1759-8486 ; 1759-8478
    ISSN (online) 1759-8486
    ISSN 1759-8478
    DOI 10.1136/jnis-2022-020035
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Identification of Biologically Essential Nodes via Determinative Power in Logical Models of Cellular Processes.

    Pentzien, Trevor / Puniya, Bhanwar L / Helikar, Tomáš / Matache, Mihaela T

    Frontiers in physiology

    2018  Volume 9, Page(s) 1185

    Abstract: A variety of biological networks can be modeled as logical or Boolean networks. However, a simplification of the reality to binary states of the nodes does not ease the difficulty of analyzing the dynamics of large, complex networks, such as signal ... ...

    Abstract A variety of biological networks can be modeled as logical or Boolean networks. However, a simplification of the reality to binary states of the nodes does not ease the difficulty of analyzing the dynamics of large, complex networks, such as signal transduction networks, due to the exponential dependence of the state space on the number of nodes. This paper considers a recently introduced method for finding a fairly small subnetwork, representing a collection of nodes that determine the states of most other nodes with a reasonable level of entropy. The subnetwork contains the most determinative nodes that yield the highest information gain. One of the goals of this paper is to propose an algorithm for finding a suitable subnetwork size. The information gain is quantified by the so-called determinative power of the nodes, which is obtained via the mutual information, a concept originating in information theory. We find the most determinative nodes for 36 network models available in the online database Cell Collective (http://cellcollective.org). We provide statistical information that indicates a weak correlation between the subnetwork size and other variables, such as network size, or maximum and average determinative power of nodes. We observe that the proportion represented by the subnetwork in comparison to the whole network shows a weak tendency to decrease for larger networks. The determinative power of nodes is weakly correlated to the number of outputs of a node, and it appears to be independent of other topological measures such as closeness or betweenness centrality. Once the subnetwork of the most determinative nodes is identified, we generate a biological function analysis of its nodes for some of the 36 networks. The analysis shows that a large fraction of the most determinative nodes are essential and involved in crucial biological functions. The biological pathway analysis of the most determinative nodes shows that they are involved in important disease pathways.
    Language English
    Publishing date 2018-08-31
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2564217-0
    ISSN 1664-042X
    ISSN 1664-042X
    DOI 10.3389/fphys.2018.01185
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  5. Article ; Online: Difference equation for tracking perturbations in systems of Boolean nested canalyzing functions.

    Dimitrova, Elena S / Yordanov, Oleg I / Matache, Mihaela T

    Physical review. E, Statistical, nonlinear, and soft matter physics

    2015  Volume 91, Issue 6, Page(s) 62812

    Abstract: This paper studies the spread of perturbations through networks composed of Boolean functions with special canalyzing properties. Canalyzing functions have the property that at least for one value of one of the inputs the output is fixed, irrespective of ...

    Abstract This paper studies the spread of perturbations through networks composed of Boolean functions with special canalyzing properties. Canalyzing functions have the property that at least for one value of one of the inputs the output is fixed, irrespective of the values of the other inputs. In this paper the focus is on partially nested canalyzing functions, in which multiple, but not all inputs have this property in a cascading fashion. They naturally describe many relationships in real networks. For example, in a gene regulatory network, the statement "if gene A is expressed, then gene B is not expressed regardless of the states of other genes" implies that A is canalyzing. On the other hand, the additional statement "if gene A is not expressed, and gene C is expressed, then gene B is automatically expressed; otherwise gene B's state is determined by some other type of rule" implies that gene B is expressed by a partially nested canalyzing function with more than two variables, but with two canalyzing variables. In this paper a difference equation model of the probability that a network node's value is affected by an initial perturbation over time is developed, analyzed, and validated numerically. It is shown that the effect of a perturbation decreases towards zero over time if the Boolean functions are canalyzing in sufficiently many variables. The maximum dynamical impact of a perturbation is shown to be comparable to the average impact for a wide range of values of the average sensitivity of the network. Percolation limits are also explored; these are parameter values which generate a transition of the expected perturbation effect to zero as other parameters are varied, so that the initial perturbation does not scale up with the parameters once the percolation limits are reached.
    MeSH term(s) Models, Theoretical
    Language English
    Publishing date 2015-06
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1550-2376
    ISSN (online) 1550-2376
    DOI 10.1103/PhysRevE.91.062812
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  6. Article ; Online: What Is Different in Acute Hematologic Malignancy-Associated ARDS? An Overview of the Literature.

    Cotorogea-Simion, Mihail / Pavel, Bogdan / Isac, Sebastian / Telecan, Teodora / Matache, Irina-Mihaela / Bobirca, Anca / Bobirca, Florin-Teodor / Rababoc, Razvan / Droc, Gabriela

    Medicina (Kaunas, Lithuania)

    2022  Volume 58, Issue 9

    Abstract: Background and ... ...

    Abstract Background and Objectives
    MeSH term(s) Hematologic Neoplasms/complications ; Humans ; Leukemic Infiltration/complications ; Leukemic Infiltration/pathology ; Leukostasis/complications ; Leukostasis/pathology ; Lung/pathology ; Lung Diseases ; Respiratory Distress Syndrome/etiology ; Respiratory Distress Syndrome/therapy
    Language English
    Publishing date 2022-09-03
    Publishing country Switzerland
    Document type Journal Article ; Review
    ZDB-ID 2188113-3
    ISSN 1648-9144 ; 1010-660X
    ISSN (online) 1648-9144
    ISSN 1010-660X
    DOI 10.3390/medicina58091215
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  7. Article ; Online: Operator self-similar processes on Banach spaces

    Mihaela T. Matache / Valentin Matache

    Journal of Applied Mathematics and Stochastic Analysis, Vol

    2006  Volume 2006

    Abstract: Operator self-similar (OSS) stochastic processes on arbitrary Banach spaces are considered. If the family of expectations of such a process is a spanning subset of the space, it is proved that the scaling family of operators of the process under ... ...

    Abstract Operator self-similar (OSS) stochastic processes on arbitrary Banach spaces are considered. If the family of expectations of such a process is a spanning subset of the space, it is proved that the scaling family of operators of the process under consideration is a uniquely determined multiplicative group of operators. If the expectation-function of the process is continuous, it is proved that the expectations of the process have power-growth with exponent greater than or equal to 0, that is, their norm is less than a nonnegative constant times such a power-function, provided that the linear space spanned by the expectations has category 2 (in the sense of Baire) in its closure. It is shown that OSS processes whose expectation-function is differentiable on an interval (s0,∞), for some s0≥1, have a unique scaling family of operators of the form {sH:s>0}, if the expectations of the process span a dense linear subspace of category 2. The existence of a scaling family of the form {sH:s>0} is proved for proper Hilbert space OSS processes with an Abelian scaling family of positive operators.
    Keywords Science ; Q ; Mathematics ; QA1-939
    Subject code 510
    Language English
    Publishing date 2006-01-01T00:00:00Z
    Publisher Hindawi Publishing Corporation
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: Operator self-similar processes on Banach spaces

    Mihaela T. Matache / Valentin Matache

    Journal of Applied Mathematics and Stochastic Analysis, Vol

    2006  Volume 2006

    Keywords Science ; Q ; Mathematics ; QA1-939
    Language English
    Publishing date 2006-01-01T00:00:00Z
    Publisher Hindawi Publishing Corporation
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article: Microstructural and Tensile Properties Anisotropy of Selective Laser Melting Manufactured IN 625.

    Condruz, Mihaela Raluca / Matache, Gheorghe / Paraschiv, Alexandru / Frigioescu, Tiberius Florian / Badea, Teodor

    Materials (Basel, Switzerland)

    2020  Volume 13, Issue 21

    Abstract: The present study was focused on the assessment of microstructural anisotropy of IN 625 manufactured by selective laser melting (SLM) and its influence on the material's room temperature tensile properties. Microstructural anisotropy was assessed based ... ...

    Abstract The present study was focused on the assessment of microstructural anisotropy of IN 625 manufactured by selective laser melting (SLM) and its influence on the material's room temperature tensile properties. Microstructural anisotropy was assessed based on computational and experimental investigations. Tensile specimens were manufactured using four building orientations (along
    Language English
    Publishing date 2020-10-28
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2487261-1
    ISSN 1996-1944
    ISSN 1996-1944
    DOI 10.3390/ma13214829
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Advancements in dendritic cell vaccination: enhancing efficacy and optimizing combinatorial strategies for the treatment of glioblastoma.

    Subtirelu, Robert C / Teichner, Eric M / Ashok, Arjun / Parikh, Chitra / Talasila, Sahithi / Matache, Irina-Mihaela / Alnemri, Ahab G / Anderson, Victoria / Shahid, Osmaan / Mannam, Sricharvi / Lee, Andrew / Werner, Thomas / Revheim, Mona-Elisabeth / Alavi, Abass

    Frontiers in neurology

    2023  Volume 14, Page(s) 1271822

    Abstract: Glioblastomas (GBM) are highly invasive, malignant primary brain tumors. The overall prognosis is poor, and management of GBMs remains a formidable challenge, necessitating novel therapeutic strategies such as dendritic cell vaccinations (DCVs). While ... ...

    Abstract Glioblastomas (GBM) are highly invasive, malignant primary brain tumors. The overall prognosis is poor, and management of GBMs remains a formidable challenge, necessitating novel therapeutic strategies such as dendritic cell vaccinations (DCVs). While many early clinical trials demonstrate an induction of an antitumoral immune response, outcomes are mixed and dependent on numerous factors that vary between trials. Optimization of DCVs is essential; the selection of GBM-specific antigens and the utilization of
    Language English
    Publishing date 2023-10-31
    Publishing country Switzerland
    Document type Journal Article ; Review
    ZDB-ID 2564214-5
    ISSN 1664-2295
    ISSN 1664-2295
    DOI 10.3389/fneur.2023.1271822
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