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  1. Article: Known components of the immunoglobulin A:T mutational machinery are intact in Burkitt lymphoma cell lines with G:C bias.

    Xiao, Zheng / Ray, Madhumita / Jiang, Chuancang / Clark, Alan B / Rogozin, Igor B / Diaz, Marilyn

    Molecular immunology

    2007  Volume 44, Issue 10, Page(s) 2659–2666

    Abstract: ... in various DNA repair proteins implicated in A:T mutation and found a previously unappreciated bias at G:C ... The basis for mutations at A:T base pairs in immunoglobulin hypermutation and defining how AID ... that introduces A:T mutations. Additionally, we asked if any of the known components of the A:T mutation machinery ...

    Abstract The basis for mutations at A:T base pairs in immunoglobulin hypermutation and defining how AID interacts with the DNA of the immunoglobulin locus are major aspects of the immunoglobulin mutator mechanism where questions remain unanswered. Here, we examined the pattern of mutations generated in mice deficient in various DNA repair proteins implicated in A:T mutation and found a previously unappreciated bias at G:C base pairs in spectra from mice simultaneously deficient in DNA mismatch repair and uracil DNA glycosylase. This suggests a strand-biased DNA transaction for AID delivery which is then masked by the mechanism that introduces A:T mutations. Additionally, we asked if any of the known components of the A:T mutation machinery underscore the basis for the paucity of A:T mutations in the Burkitt lymphoma cell lines, Ramos and BL2. Ramos and BL2 cells were proficient in MSH2/MSH6-mediated mismatch repair, and express high levels of wild-type, full-length DNA polymerase eta. In addition, Ramos cells have high levels of uracil DNA glycosylase protein and are proficient in base excision repair. These results suggest that Burkitt lymphoma cell lines may be deficient in an unidentified factor that recruits the machinery necessary for A:T mutation or that AID-mediated cytosine deamination in these cells may be processed by conventional base excision repair truncating somatic hypermutation at the G:C phase. Either scenario suggests that cytosine deamination by AID is not enough to trigger A:T mutation, and that additional unidentified factors are required for full spectrum hypermutation in vivo.
    MeSH term(s) Adenosine Triphosphate/genetics ; Animals ; Burkitt Lymphoma/genetics ; Cell Line, Tumor ; Cytidine Deaminase/metabolism ; Cytidine Triphosphate/genetics ; DNA Mismatch Repair ; DNA Repair Enzymes/genetics ; Guanosine Triphosphate/genetics ; Humans ; Mice ; Mutation ; Nucleotides/genetics ; Somatic Hypermutation, Immunoglobulin/genetics ; Thymine Nucleotides/genetics
    Chemical Substances Nucleotides ; Thymine Nucleotides ; Cytidine Triphosphate (65-47-4) ; Guanosine Triphosphate (86-01-1) ; Adenosine Triphosphate (8L70Q75FXE) ; AICDA (activation-induced cytidine deaminase) (EC 3.5.4.-) ; Cytidine Deaminase (EC 3.5.4.5) ; DNA Repair Enzymes (EC 6.5.1.-) ; thymidine 5'-triphosphate (QOP4K539MU)
    Language English
    Publishing date 2007-04
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Intramural
    ZDB-ID 424427-8
    ISSN 1872-9142 ; 0161-5890
    ISSN (online) 1872-9142
    ISSN 0161-5890
    DOI 10.1016/j.molimm.2006.12.006
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: The G-to-T point mutation in codon 34 of the factor XIII gene and the risk of pre-eclampsia.

    Clark, Peter / Freeman, Dilys J / Streja, Elani / Sattar, Naveed / Walker, Isobel D / Greer, Ian A

    Blood coagulation & fibrinolysis : an international journal in haemostasis and thrombosis

    2003  Volume 14, Issue 2, Page(s) 155–157

    Abstract: A G-to-T point mutation in exon 2 of the FXIII A-subunit gene results in a leucine rather ... of cases. In subjects heterozygous for the T genotype (GT) the relative risk of pre-eclampsia was 0.7 [95 ... confidence interval (CI95 ) 0.4-1.1] when compared with the GG genotype. For subjects homozygous for the T allele ...

    Abstract A G-to-T point mutation in exon 2 of the FXIII A-subunit gene results in a leucine rather than valine at amino acid position 34 of the factor XIII molecule. The presence of leucine has been associated with a reduced risk of both arterial and venous thrombosis. We examined the prevalence of this point mutation in 102 cases of pre-eclampsia and 208 matched control subjects, as inherited and acquired risk factors for arterial and venous thrombosis are associated with an increased risk of pre-eclampsia. The GT genotype was observed in 38% of controls and 29.4% of cases and the TT genotype was observed in 6.7% of controls and 5.9% of cases. In subjects heterozygous for the T genotype (GT) the relative risk of pre-eclampsia was 0.7 [95% confidence interval (CI95 ) 0.4-1.1] when compared with the GG genotype. For subjects homozygous for the T allele the relative risk for pre-eclampsia was 0.8 (CI95 0.3-2.1) when compared with the GG genotype. The risk associated with the T allele in the heterozygous and homozygous forms compared with the GG genotype was 0.7 (CI95 0.4-1.1). We conclude that the presence of leucine at this site is not associated with a protection against pre-eclampsia to the magnitude of that reported in other thrombotic disease.
    MeSH term(s) Adult ; Alleles ; Amino Acid Substitution ; Codon/genetics ; Factor XIII/genetics ; Female ; Gene Frequency ; Genotype ; Humans ; Leucine/genetics ; Odds Ratio ; Point Mutation ; Pre-Eclampsia/genetics ; Pregnancy ; Risk Factors ; Valine/genetics
    Chemical Substances Codon ; Factor XIII (9013-56-3) ; Leucine (GMW67QNF9C) ; Valine (HG18B9YRS7)
    Language English
    Publishing date 2003-01-28
    Publishing country England
    Document type Journal Article
    ZDB-ID 1033551-1
    ISSN 0957-5235
    ISSN 0957-5235
    DOI 10.1097/00001721-200302000-00006
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Special Issue in Honor of Professor Mary Garson AM.

    Blanchfield, Joanne T / Nonato, Maribel G / Clark, Richard J

    Journal of natural products

    2023  Volume 86, Issue 3, Page(s) 473–474

    Language English
    Publishing date 2023-03-22
    Publishing country United States
    Document type Editorial
    ZDB-ID 304325-3
    ISSN 1520-6025 ; 0163-3864
    ISSN (online) 1520-6025
    ISSN 0163-3864
    DOI 10.1021/acs.jnatprod.3c00088
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Integrative Analysis of Differentially Expressed Genes in Time-Course Multi-Omics Data with MINT-DE.

    Xue, Hao / Delbare, Sofie Y N / Wells, Martin T / Basu, Sumanta / Clark, Andrew G

    Research square

    2024  

    Abstract: Background: Time-course multi-omics experiments have been highly informative for obtaining a comprehensive understanding of the dynamic relationships between molecules in a biological process, especially if the different profiles are obtained from the ... ...

    Abstract Background: Time-course multi-omics experiments have been highly informative for obtaining a comprehensive understanding of the dynamic relationships between molecules in a biological process, especially if the different profiles are obtained from the same samples. A fundamental step in analyzing time-course multi-omics data involves selecting a short list of genes or gene regions ("sites") that warrant further study. Two important criteria for site selection are the magnitude of change and the temporal dynamic consistency. However, existing methods only consider one of these criteria, while neglecting the other.
    Results: In our study, we propose a framework called MINT-DE (
    Conclusions: These findings suggest the effectiveness of MINT-DE in selecting sites that are both differentially expressed within at least one assay and temporally related across assays. This highlights the potential of MINT-DE to identify biologically important sites for downstream analysis and provide a complementarity of sites that is neglected by existing methods.
    Language English
    Publishing date 2024-01-01
    Publishing country United States
    Document type Preprint
    DOI 10.21203/rs.3.rs-3806701/v1
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: N-Cα Bond Cleavage Catalyzed by a Multinuclear Iron Oxygenase from a Divergent Methanobactin-like RiPP Gene Cluster.

    Chioti, Vasiliki T / Clark, Kenzie A / Ganley, Jack G / Han, Esther J / Seyedsayamdost, Mohammad R

    Journal of the American Chemical Society

    2024  Volume 146, Issue 11, Page(s) 7313–7323

    Abstract: DUF692 multinuclear iron oxygenases (MNIOs) are an emerging family of tailoring enzymes involved in the biosynthesis of ribosomally synthesized and post-translationally modified peptides (RiPPs). Three members, MbnB, TglH, and ChrH, have been ... ...

    Abstract DUF692 multinuclear iron oxygenases (MNIOs) are an emerging family of tailoring enzymes involved in the biosynthesis of ribosomally synthesized and post-translationally modified peptides (RiPPs). Three members, MbnB, TglH, and ChrH, have been characterized to date and shown to catalyze unusual and complex transformations. Using a co-occurrence-based bioinformatic search strategy, we recently generated a sequence similarity network of MNIO-RiPP operons that encode one or more MNIOs adjacent to a transporter. The network revealed >1000 unique gene clusters, evidence of an unexplored biosynthetic landscape. Herein, we assess an MNIO-RiPP cluster from this network that is encoded in Proteobacteria and Actinobacteria. The cluster, which we have termed
    MeSH term(s) Oxygenases/genetics ; Protein Processing, Post-Translational ; Peptides/chemistry ; Multigene Family ; Catalysis ; Imidazoles ; Oligopeptides
    Chemical Substances methanobactin ; Oxygenases (EC 1.13.-) ; Peptides ; Imidazoles ; Oligopeptides
    Language English
    Publishing date 2024-03-07
    Publishing country United States
    Document type Journal Article
    ZDB-ID 3155-0
    ISSN 1520-5126 ; 0002-7863
    ISSN (online) 1520-5126
    ISSN 0002-7863
    DOI 10.1021/jacs.3c11740
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Addressing Circadian Disruptions in Visually Impaired Paralympic Athletes.

    Anderson, Travis / Adams, William M / Burns, Geoffrey T / Post, Eric G / Baumann, Sally / Clark, Emily / Cogan, Karen / Finnoff, Jonathan T

    International journal of sports physiology and performance

    2024  Volume 19, Issue 2, Page(s) 212–218

    Abstract: Purpose: Transmeridian travel is common for elite athletes participating in competitions and training. However, this travel can lead to circadian misalignment wherein the internal biological clock becomes desynchronized with the light-dark cycle of the ... ...

    Abstract Purpose: Transmeridian travel is common for elite athletes participating in competitions and training. However, this travel can lead to circadian misalignment wherein the internal biological clock becomes desynchronized with the light-dark cycle of the new environment, resulting in performance decrement and potential negative health consequences. Existing literature extensively discusses recommendations for managing jet lag, predominantly emphasizing light-based interventions to synchronize the internal clock with the anticipated time at the destination. Nevertheless, visually impaired (VI) athletes may lack photoreceptiveness, diminishing or nullifying the effectiveness of this therapy. Consequently, this invited commentary explores alternative strategies for addressing jet lag in VI athletes.
    Conclusions: VI athletes with light perception but reduced visual acuity or visual fields may still benefit from light interventions in managing jet lag. However, VI athletes lacking a conscious perception of light should rely on gradual shifts in behavioral factors, such as meal timing and exercise, to facilitate the entrainment of circadian rhythms to the destination time. Furthermore, interventions like melatonin supplementation may prove useful during and after travel. In addition, it is recommended that athlete guides adopt phase-forward or phase-back approaches to synchronize with the athlete, aiding in jet-lag management and optimizing performance.
    MeSH term(s) Humans ; Jet Lag Syndrome ; Para-Athletes ; Melatonin ; Circadian Rhythm ; Athletes
    Chemical Substances Melatonin (JL5DK93RCL)
    Language English
    Publishing date 2024-01-02
    Publishing country United States
    Document type Journal Article
    ISSN 1555-0273
    ISSN (online) 1555-0273
    DOI 10.1123/ijspp.2023-0267
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Transmission of Spinach Downy Mildew via Seed and Infested Leaf Debris.

    Klosterman, Steven J / Clark, Kelley J / Anchieta, Amy G / Kandel, Shyam L / Mou, Beiquan / McGrath, Margaret T / Correll, James C / Shishkoff, Nina

    Plant disease

    2024  , Page(s) PDIS06231225RE

    Abstract: Spinach downy mildew, caused by the obligate oomycete ... ...

    Abstract Spinach downy mildew, caused by the obligate oomycete pathogen
    Language English
    Publishing date 2024-03-26
    Publishing country United States
    Document type Journal Article
    ZDB-ID 754182-x
    ISSN 0191-2917
    ISSN 0191-2917
    DOI 10.1094/PDIS-06-23-1225-RE
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Projected decrease in trail access in the Arctic.

    Ford, J D / Clark, D G / Copland, L / Pearce, T / Harper, S L

    Communications earth & environment

    2023  Volume 4, Issue 1, Page(s) 23

    Abstract: Transportation systems in northern Canada are highly sensitive to climate change. We project how access to semi-permanent trails on land, water, and sea ice might change this century in Inuit Nunangat (the Inuit homeland in northern Canada), using CMIP6 ... ...

    Abstract Transportation systems in northern Canada are highly sensitive to climate change. We project how access to semi-permanent trails on land, water, and sea ice might change this century in Inuit Nunangat (the Inuit homeland in northern Canada), using CMIP6 projections coupled with trail access models developed with community members. Overall trail access is projected to diminish, with large declines in access for sea ice trails which play a central role for Inuit livelihoods and culture; limits to adaptation in southern regions of Inuit Nunangat within the next 40 years; a lengthening of the period when no trails are accessible; and an unequal distribution of impacts according to the knowledge, skills, equipment, and risk tolerance of trail users. There are opportunities for adaptation through efforts to develop skillsets and confidence in travelling in more marginal environmental conditions, which can considerably extend the envelope of days when trails are accessible and months when this is possible. Such actions could reduce impacts across emissions scenarios but their potential effectiveness declines at higher levels of global warming, and in southern regions only delays when sea ice trails become unusable.
    Language English
    Publishing date 2023-02-03
    Publishing country England
    Document type Journal Article
    ISSN 2662-4435
    ISSN (online) 2662-4435
    DOI 10.1038/s43247-023-00685-w
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Modeled Vegetation Community Trajectories: Effects from Climate Change, Atmospheric Nitrogen Deposition, and Soil Acidification Recovery.

    McDonnell, T C / Clark, C M / Reinds, G J / Sullivan, T J / Knees, B

    Environmental advances

    2023  Volume 9, Page(s) 1–13

    Abstract: Forest understory plant communities in the United States harbor most of the vegetation diversity of forests and are often sensitive to changes in climate and atmospheric deposition of nitrogen (N). As temperature increases from human-caused climate ... ...

    Abstract Forest understory plant communities in the United States harbor most of the vegetation diversity of forests and are often sensitive to changes in climate and atmospheric deposition of nitrogen (N). As temperature increases from human-caused climate change and soils recover from long term atmospheric deposition of N and sulfur (S), it is unclear how these important ecosystem components will respond. We used the newly developed US-PROPS model - based on species response functions for over 1,500 species - to evaluate the potential impacts of atmospheric N deposition and climate change on species occurrence probability for a case study in the forested ecosystems of the Great Smoky Mountains National Park (GRSM), an iconic park in the southeastern United States. We evaluated six future scenarios from various combinations of two potential recoveries of soil pH (no change, +0.5 pH units) and three climate futures (no change, +1.5, +3.0 deg C). Species critical loads (CLs) of N deposition and projected responses for each scenario were determined. Critical loads were estimated to be low (< 2 kg N/ha/yr) to protect all species under current and expected future conditions across broad regions of GRSM and these CLs were exceeded at large spatial extents among scenarios. Northern hardwood, yellow pine, and chestnut oak forests were among the most N-sensitive vegetation map classes found within GRSM. Potential future air temperature conditions generally led to decreases in the maximum occurrence probability for species. Therefore, CLs were considered "unattainable" in these situations because the specified level of protection used for CL determination (i.e., maximum occurrence probability under ambient conditions) was not attainable. Although some species showed decreases in maximum occurrence probability with simulated increases in soil pH, most species were favored by increased pH. The importance of our study is rooted in the methodology described here for establishing regional CLs and for evaluating future conditions, which is transferable to other national parks in the U.S. and in Europe where the original PROPS model was developed.
    Language English
    Publishing date 2023-03-26
    Publishing country England
    Document type Journal Article
    ISSN 2666-7657
    ISSN (online) 2666-7657
    DOI 10.1016/j.envadv.2022.100271
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: The value of virtual biobanks for transparency purposes with respect to reagents and samples used during test development and validation.

    Watson, J W / Clark, G / Williams, D T

    Revue scientifique et technique (International Office of Epizootics)

    2021  Volume 40, Issue 1, Page(s) 253–259

    Abstract: Biobanks represent a valuable resource in many areas of biomedical research and development. They function as repositories for well-documented and well-characterised biological material that can be used as the basis for this work. Virtual biobanks ... ...

    Abstract Biobanks represent a valuable resource in many areas of biomedical research and development. They function as repositories for well-documented and well-characterised biological material that can be used as the basis for this work. Virtual biobanks amplify the availability of this resource by linking multiple biobanks via a single interface. Test development and validation is an essential process that helps to provide confidence in diagnostic test results and, by extension, the disease and health status of animal populations demonstrated by such results. The quality of the development and validation pathway can be enhanced by the use of well-characterised material for standards and validation panels. Virtual biobanks represent a powerful mechanism for enhancing access to such material, and allow other parties to both have greater confidence in the work done, and to be able to repeat it themselves, as required.
    MeSH term(s) Animals ; Biological Specimen Banks ; Biomedical Research ; Indicators and Reagents
    Chemical Substances Indicators and Reagents
    Language English
    Publishing date 2021-06-04
    Publishing country France
    Document type Journal Article
    ZDB-ID 792125-1
    ISSN 1608-0637 ; 0253-1933
    ISSN (online) 1608-0637
    ISSN 0253-1933
    DOI 10.20506/rst.40.1.3222
    Database MEDical Literature Analysis and Retrieval System OnLINE

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