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  1. Article ; Online: SMC5/6 complex-mediated SUMOylation stimulates DNA-protein cross-link repair in Arabidopsis.

    Dvořák Tomaštíková, Eva / Prochazkova, Klara / Yang, Fen / Jemelkova, Jitka / Finke, Andreas / Dorn, Annika / Said, Mahmoud / Puchta, Holger / Pecinka, Ales

    The Plant cell

    2023  Volume 35, Issue 5, Page(s) 1532–1547

    Abstract: DNA-protein cross-links (DPCs) are highly toxic DNA lesions consisting of proteins covalently attached to chromosomal DNA. Unrepaired DPCs physically block DNA replication and transcription. Three DPC repair pathways have been identified in Arabidopsis ( ... ...

    Abstract DNA-protein cross-links (DPCs) are highly toxic DNA lesions consisting of proteins covalently attached to chromosomal DNA. Unrepaired DPCs physically block DNA replication and transcription. Three DPC repair pathways have been identified in Arabidopsis (Arabidopsis thaliana) to date: the endonucleolytic cleavage of DNA by the structure-specific endonuclease MUS81; proteolytic degradation of the crosslinked protein by the metalloprotease WSS1A; and cleavage of the cross-link phosphodiester bonds by the tyrosyl phosphodiesterases TDP1 and TDP2. Here we describe the evolutionary conserved STRUCTURAL MAINTENANCE OF CHROMOSOMEs SMC5/6 complex as a crucial component involved in DPC repair. We identified multiple alleles of the SMC5/6 complex core subunit gene SMC6B via a forward-directed genetic screen designed to identify the factors involved in the repair of DPCs induced by the cytidine analog zebularine. We monitored plant growth and cell death in response to DPC-inducing chemicals, which revealed that the SMC5/6 complex is essential for the repair of several types of DPCs. Genetic interaction and sensitivity assays showed that the SMC5/6 complex works in parallel to the endonucleolytic and proteolytic pathways. The repair of zebularine-induced DPCs was associated with SMC5/6-dependent SUMOylation of the damage sites. Thus, we present the SMC5/6 complex as an important factor in plant DPC repair.
    MeSH term(s) Arabidopsis/genetics ; Arabidopsis/metabolism ; Sumoylation ; DNA Repair/genetics ; DNA Damage ; Proteins/metabolism ; DNA/metabolism ; Cell Cycle Proteins/genetics ; Cell Cycle Proteins/metabolism
    Chemical Substances Proteins ; DNA (9007-49-2) ; Cell Cycle Proteins
    Language English
    Publishing date 2023-01-27
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 623171-8
    ISSN 1532-298X ; 1040-4651
    ISSN (online) 1532-298X
    ISSN 1040-4651
    DOI 10.1093/plcell/koad020
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Book ; Online: List Locally Surjective Homomorphisms in Hereditary Graph Classes

    Dvořák, Pavel / Krawczyk, Monika / Masařík, Tomáš / Novotná, Jana / Rzążewski, Paweł / Żuk, Aneta

    2022  

    Abstract: ... graphs that exclude a fixed graph $F$ as an induced subgraph. We aim to understand for which pairs $(H,F ... from its list. In this paper, we study the complexity of the LLSHom($H$) problem in $F$-free graphs, i.e ... from $V(G)$ to $V(H)$ that is surjective in the neighborhood of each vertex in $G$. In the list locally ...

    Abstract A locally surjective homomorphism from a graph $G$ to a graph $H$ is an edge-preserving mapping from $V(G)$ to $V(H)$ that is surjective in the neighborhood of each vertex in $G$. In the list locally surjective homomorphism problem, denoted by LLSHom($H$), the graph $H$ is fixed and the instance consists of a graph $G$ whose every vertex is equipped with a subset of $V(H)$, called list. We ask for the existence of a locally surjective homomorphism from $G$ to $H$, where every vertex of $G$ is mapped to a vertex from its list. In this paper, we study the complexity of the LLSHom($H$) problem in $F$-free graphs, i.e., graphs that exclude a fixed graph $F$ as an induced subgraph. We aim to understand for which pairs $(H,F)$ the problem can be solved in subexponential time. We show that for all graphs $H$, for which the problem is NP-hard in general graphs, it cannot be solved in subexponential time in $F$-free graphs unless $F$ is a bounded-degree forest or the ETH fails. The initial study reveals that a natural subfamily of bounded-degree forests $F$ that might lead to some tractability results is the family $\mathcal S$ consisting of forests whose every component has at most three leaves. In this case, we exhibit the following dichotomy theorem: besides the cases that are polynomial-time solvable in general graphs, the graphs $H \in \{P_3,C_4\}$ are the only connected ones that allow for a subexponential-time algorithm in $F$-free graphs for every $F \in \mathcal S$ (unless the ETH fails).

    Comment: 26 pages, 8 figures
    Keywords Computer Science - Data Structures and Algorithms ; Computer Science - Computational Complexity
    Subject code 511
    Publishing date 2022-02-24
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Sustainable green roofs: a comprehensive review of influential factors.

    Shahmohammad, Mohsen / Hosseinzadeh, Majid / Dvorak, Bruce / Bordbar, Farzaneh / Shahmohammadmirab, Hamid / Aghamohammadi, Nasrin

    Environmental science and pollution research international

    2022  Volume 29, Issue 52, Page(s) 78228–78254

    Abstract: Green roofs have gained much attention as a modern roofing surface due to their potential to deliver many environmental and social benefits. Studies have indicated that different GR designs deliver different ecosystem services, and there are important ... ...

    Abstract Green roofs have gained much attention as a modern roofing surface due to their potential to deliver many environmental and social benefits. Studies have indicated that different GR designs deliver different ecosystem services, and there are important factors that affect GR performance. This article reviewed significant factors that influence GR performance and sustainability. Substrate and drainage layer material choice significantly affects stormwater retention potential, leachate quality, plant survival, and determines GR environmental footprints. Subsequently, type of plants, their form, and kinds used on GRs impact GR ecosystem function. Leaf area is the most studied trait due to its influence on the cooling potential and energy performance. In order to achieve a sustainable GR, it is essential to select the type of plants that have a high survival rate. Perennial herbs, particularly forbs and grass as dominant groups, are heat and drought tolerant, which make them suitable in GR experiment. Furthermore, selecting a suitable irrigation system is as important as two other factors for having a sustainable GR. Irrigation is essential for plant survival, and due to the current pressure on valuable water sources, it is important to select a sustainable irrigation system. This review presents three sustainable irrigation methods: (i) employing alternative water sources such as rainwater, greywater, and atmospheric water; (ii) smart irrigation and monitoring; and (iii) using adaptive materials and additives that improve GR water use. This review sheds new insights on the design of high-performance, sustainable GRs and provides guidance for the legislation of sustainable GR.
    MeSH term(s) Ecosystem ; Conservation of Natural Resources ; Plants ; Water ; Smart Materials
    Chemical Substances Water (059QF0KO0R) ; Smart Materials
    Language English
    Publishing date 2022-10-03
    Publishing country Germany
    Document type Journal Article ; Review
    ZDB-ID 1178791-0
    ISSN 1614-7499 ; 0944-1344
    ISSN (online) 1614-7499
    ISSN 0944-1344
    DOI 10.1007/s11356-022-23405-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Monoterpenoid aryl hydrocarbon receptor allosteric antagonists protect against ultraviolet skin damage in female mice.

    Ondrová, Karolína / Zůvalová, Iveta / Vyhlídalová, Barbora / Krasulová, Kristýna / Miková, Eva / Vrzal, Radim / Nádvorník, Petr / Nepal, Binod / Kortagere, Sandhya / Kopečná, Martina / Kopečný, David / Šebela, Marek / Rastinejad, Fraydoon / Pu, Hua / Soural, Miroslav / Rolfes, Katharina Maria / Haarmann-Stemmann, Thomas / Li, Hao / Mani, Sridhar /
    Dvořák, Zdeněk

    Nature communications

    2023  Volume 14, Issue 1, Page(s) 2728

    Abstract: The human aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that is a pivotal regulator of human physiology and pathophysiology. Allosteric inhibition of AhR was previously thought to be untenable. Here, we identify carvones as ... ...

    Abstract The human aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that is a pivotal regulator of human physiology and pathophysiology. Allosteric inhibition of AhR was previously thought to be untenable. Here, we identify carvones as noncompetitive, insurmountable antagonists of AhR and characterize the structural and functional consequences of their binding. Carvones do not displace radiolabeled ligands from binding to AhR but instead bind allosterically within the bHLH/PAS-A region of AhR. Carvones do not influence the translocation of ligand-activated AhR into the nucleus but inhibit the heterodimerization of AhR with its canonical partner ARNT and subsequent binding of AhR to the promoter of CYP1A1. As a proof of concept, we demonstrate physiologically relevant Ahr-antagonism by carvones in vivo in female mice. These substances establish the molecular basis for selective targeting of AhR regardless of the type of ligand(s) present and provide opportunities for the treatment of disease processes modified by AhR.
    MeSH term(s) Animals ; Female ; Mice ; Aryl Hydrocarbon Receptor Nuclear Translocator/genetics ; Aryl Hydrocarbon Receptor Nuclear Translocator/metabolism ; Cytochrome P-450 CYP1A1/genetics ; Ligands ; Promoter Regions, Genetic ; Receptors, Aryl Hydrocarbon/genetics ; Receptors, Aryl Hydrocarbon/metabolism ; Skin/metabolism ; Skin/radiation effects ; Ultraviolet Rays/adverse effects
    Chemical Substances Aryl Hydrocarbon Receptor Nuclear Translocator (138391-32-9) ; Cytochrome P-450 CYP1A1 (EC 1.14.14.1) ; Ligands ; Receptors, Aryl Hydrocarbon
    Language English
    Publishing date 2023-05-11
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-023-38478-6
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Book ; Online: Parameterized Inapproximability of Independent Set in $H$-Free Graphs

    Dvořák, Pavel / Feldmann, Andreas Emil / Rai, Ashutosh / Rzążewski, Paweł

    2020  

    Abstract: ... alpha(H))}$ algorithm in $H$-free graphs and under Gap-ETH there is no $d/k^{o(1)}$-approximation for $K ... We study the Independent Set (IS) problem in $H$-free graphs, i.e., graphs excluding some fixed ... graph $H$ as an induced subgraph. We prove several inapproximability results both for polynomial-time ...

    Abstract We study the Independent Set (IS) problem in $H$-free graphs, i.e., graphs excluding some fixed graph $H$ as an induced subgraph. We prove several inapproximability results both for polynomial-time and parameterized algorithms. Halld\'orsson [SODA 1995] showed that for every $\delta>0$ IS has a polynomial-time $(\frac{d-1}{2}+\delta)$-approximation in $K_{1,d}$-free graphs. We extend this result by showing that $K_{a,b}$-free graphs admit a polynomial-time $O(\alpha(G)^{1-1/a})$-approximation, where $\alpha(G)$ is the size of a maximum independent set in $G$. Furthermore, we complement the result of Halld\'orsson by showing that for some $\gamma=\Theta(d/\log d),$ there is no polynomial-time $\gamma$-approximation for these graphs, unless NP = ZPP. Bonnet et al. [IPEC 2018] showed that IS parameterized by the size $k$ of the independent set is W[1]-hard on graphs which do not contain (1) a cycle of constant length at least $4$, (2) the star $K_{1,4}$, and (3) any tree with two vertices of degree at least $3$ at constant distance. We strengthen this result by proving three inapproximability results under different complexity assumptions for almost the same class of graphs (we weaken condition (2) that $G$ does not contain $K_{1,5}$). First, under the ETH, there is no $f(k)\cdot n^{o(k/\log k)}$ algorithm for any computable function $f$. Then, under the deterministic Gap-ETH, there is a constant $\delta>0$ such that no $\delta$-approximation can be computed in $f(k) \cdot n^{O(1)}$ time. Also, under the stronger randomized Gap-ETH there is no such approximation algorithm with runtime $f(k)\cdot n^{o(\sqrt{k})}$. Finally, we consider the parameterization by the excluded graph $H$, and show that under the ETH, IS has no $n^{o(\alpha(H))}$ algorithm in $H$-free graphs and under Gap-ETH there is no $d/k^{o(1)}$-approximation for $K_{1,d}$-free graphs with runtime $f(d,k) n^{O(1)}$.

    Comment: Preliminary version of the paper in WG 2020 proceedings
    Keywords Computer Science - Computational Complexity ; F.2
    Subject code 511
    Publishing date 2020-06-18
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Fertility Preservation Practices at Pediatric Oncology Institutions in the United States: A Report From the Children's Oncology Group.

    Frederick, Natasha N / Klosky, James L / Meacham, Lillian / Quinn, Gwendolyn P / Kelvin, Joanne F / Cherven, Brooke / Freyer, David R / Dvorak, Christopher C / Brackett, Julienne / Ahmed-Winston, Sameeya / Bryson, Elyse / Su, H Irene / Chow, Eric J / Levine, Jennifer

    JCO oncology practice

    2023  Volume 19, Issue 4, Page(s) e550–e558

    Abstract: Purpose: Fertility discussions are an integral part of comprehensive care for pediatric, adolescent, and young adult patients newly diagnosed with cancer and are supported by national guidelines. Current institutional practices are poorly understood.: ...

    Abstract Purpose: Fertility discussions are an integral part of comprehensive care for pediatric, adolescent, and young adult patients newly diagnosed with cancer and are supported by national guidelines. Current institutional practices are poorly understood.
    Methods: A cross-sectional survey was distributed to 220 Children's Oncology Group member institutions regarding fertility discussion practices. Descriptive statistics were calculated for all variables. The association between specific practices and selected outcomes on the basis of sex was examined via multivariable logistic regression.
    Results: One hundred forty-four programs (65.5%) returned surveys. Of these, 65 (45.1%) reported routine discussions of fertility with all female patients and 55 (38.5%) all male patients (
    Conclusion: Despite recommended guidelines, fertility discussions with patients/families before treatment initiation are not routine at Children's Oncology Group institutions. Standard criteria to determine which options should be offered to patients are more common for males than females.
    MeSH term(s) Adolescent ; Young Adult ; Humans ; Male ; Female ; Child ; United States ; Fertility Preservation ; Cross-Sectional Studies ; Semen ; Medical Oncology ; Neoplasms/complications ; Neoplasms/therapy
    Language English
    Publishing date 2023-02-10
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 3028198-2
    ISSN 2688-1535 ; 2688-1527
    ISSN (online) 2688-1535
    ISSN 2688-1527
    DOI 10.1200/OP.22.00349
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Immune activation by microbiome shapes the colon mucosa: Comparison between healthy rat mucosa under conventional and germ-free conditions.

    Čaja, Fabián / Stakheev, Dmitry / Chernyavskiy, Oleksander / Křížan, Jiří / Dvořák, Jiří / Rossmann, Pavel / Štěpánková, Renata / Makovický, Peter / Makovický, Pavol / Kozáková, Hana / Vannucci, Luca

    Journal of immunotoxicology

    2021  Volume 18, Issue 1, Page(s) 37–49

    Abstract: Germ-free animals (GF) are those without a microbiome since birth. This particular biological model has become one of special interest with the growing evidence of importance of the microbiome in the life, development, adaptation, and immunity of humans ... ...

    Abstract Germ-free animals (GF) are those without a microbiome since birth. This particular biological model has become one of special interest with the growing evidence of importance of the microbiome in the life, development, adaptation, and immunity of humans and animals in the environments in which they live. Anatomical differences observed in GF compared with conventionally-reared animals (CV) has given rise to the question of the influence of commensal microflora on the development of structure and function (even immunological) of the bowel. Only recently, thanks to achievements in microscopy and associated methods, structural differences can be better evaluated and put in perspective with the immunological characteristics of GF vs. CV animals. This study, using a GF rat model, describes for the first time the possible influence that the presence of commensal microflora, continuously stimulating mucosal immunity, has on the collagen scaffold organization of the colon mucosa. Significant differences were found between CV and GF mucosa structure with higher complexity in the CV rats associated to a more activated immune environment. The immunological data suggest that, in response to the presence of a microbiome, an effective homeostatic regulation in developed by the CV rats in healthy conditions to avoid inflammation and maintain cytokine levels near the spontaneous production found in the GF animals. The results indicated that collagen scaffold adapted to the immune microenvironment; therefore, it is apparent that the microbiome was able to condition the structure of the colon mucosa.
    MeSH term(s) Animals ; Colon ; Germ-Free Life ; Immunity, Mucosal ; Intestinal Mucosa ; Microbiota ; Rats
    Language English
    Publishing date 2021-03-05
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2205064-4
    ISSN 1547-6901 ; 1547-691X
    ISSN (online) 1547-6901
    ISSN 1547-691X
    DOI 10.1080/1547691X.2021.1887412
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Angiogenesis: update 2005.

    Dvorak, H F

    Journal of thrombosis and haemostasis : JTH

    2005  Volume 3, Issue 8, Page(s) 1835–1842

    Abstract: Angiogenesis has critical roles in normal vascular development and in important pathologies including cancer, wound healing and inflammation. This brief article will review the angiogenic response induced by the vascular permeability factor/vascular ... ...

    Abstract Angiogenesis has critical roles in normal vascular development and in important pathologies including cancer, wound healing and inflammation. This brief article will review the angiogenic response induced by the vascular permeability factor/vascular endothelial growth factor (VPF/VEGF) family of proteins and particularly VEGF-A, thought to be the single most important angiogenic factor. It will also review the steps and mechanisms by which VEGF-A induces the formation of new blood vessels and will provide an initial classification of the abnormal blood vessels that form in pathological angiogenesis. Finally, it will touch on the exciting relationships that are emerging between angiogenesis and the hemostatic and nervous systems.
    MeSH term(s) Animals ; Blood Coagulation ; Cell Proliferation ; Endothelial Growth Factors/metabolism ; Humans ; Models, Biological ; Neovascularization, Pathologic ; Neovascularization, Physiologic ; Signal Transduction ; Vascular Endothelial Growth Factor A/metabolism
    Chemical Substances Endothelial Growth Factors ; Vascular Endothelial Growth Factor A
    Language English
    Publishing date 2005-07-08
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S. ; Review
    ZDB-ID 2112661-6
    ISSN 1538-7836 ; 1538-7933
    ISSN (online) 1538-7836
    ISSN 1538-7933
    DOI 10.1111/j.1538-7836.2005.01361.x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Bidirectional Modulation of the Voltage-Gated Sodium (Nav1.6) Channel by Rationally Designed Peptidomimetics.

    Dvorak, Nolan M / Wadsworth, Paul A / Wang, Pingyuan / Chen, Haiying / Zhou, Jia / Laezza, Fernanda

    Molecules (Basel, Switzerland)

    2020  Volume 25, Issue 15

    Abstract: Disruption of protein:protein interactions (PPIs) that regulate the function of voltage-gated ... ...

    Abstract Disruption of protein:protein interactions (PPIs) that regulate the function of voltage-gated Na
    MeSH term(s) Allosteric Regulation ; Binding Sites ; Drug Design ; Fibroblast Growth Factors/chemistry ; Fibroblast Growth Factors/metabolism ; HEK293 Cells ; Humans ; Hydrophobic and Hydrophilic Interactions ; Models, Molecular ; Molecular Docking Simulation ; Molecular Structure ; NAV1.6 Voltage-Gated Sodium Channel/chemistry ; NAV1.6 Voltage-Gated Sodium Channel/metabolism ; Peptidomimetics/chemical synthesis ; Peptidomimetics/chemistry ; Peptidomimetics/pharmacology ; Protein Binding/drug effects ; Protein Structure, Secondary
    Chemical Substances NAV1.6 Voltage-Gated Sodium Channel ; Peptidomimetics ; SCN8A protein, human ; fibroblast growth factor 14 ; Fibroblast Growth Factors (62031-54-3)
    Language English
    Publishing date 2020-07-24
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 1413402-0
    ISSN 1420-3049 ; 1431-5165 ; 1420-3049
    ISSN (online) 1420-3049
    ISSN 1431-5165 ; 1420-3049
    DOI 10.3390/molecules25153365
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: The Berlin 2016 process: a summary of methodology for the 5th International Consensus Conference on Concussion in Sport.

    Meeuwisse, Willem H / Schneider, Kathryn J / Dvořák, Jiří / Omu, Onutobor Tobi / Finch, Caroline F / Hayden, K Alix / McCrory, Paul

    British journal of sports medicine

    2017  Volume 51, Issue 11, Page(s) 873–876

    Abstract: The purpose of this paper is to summarise the methodology for the 5th International Consensus Conference on Concussion in Sport. The 18 months of preparation included engagement of a scientific committee, an expert panel of 33 individuals in the field of ...

    Abstract The purpose of this paper is to summarise the methodology for the 5th International Consensus Conference on Concussion in Sport. The 18 months of preparation included engagement of a scientific committee, an expert panel of 33 individuals in the field of concussion and a modified Delphi technique to determine the primary questions to be answered. The methodology also involved the writing of 12 systematic reviews to inform the consensus conference and submission and review of scientific abstracts. The meeting itself followed a 2-day open format, a 1-day closed expert panel meeting and two additional half day meetings to develop the Concussion Recognition Tool 5 (Pocket CRT5), Sport Concussion Assessment Tool 5 (SCAT5) and Child SCAT5.
    Language English
    Publishing date 2017-06
    Publishing country England
    Document type Journal Article
    ZDB-ID 600592-5
    ISSN 1473-0480 ; 0306-3674
    ISSN (online) 1473-0480
    ISSN 0306-3674
    DOI 10.1136/bjsports-2017-097569
    Database MEDical Literature Analysis and Retrieval System OnLINE

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