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  1. Article ; Online: Fragmentation of 5-fluorouridine induced by low energy (< 12 eV) electrons: insights into the radiosensitization of DNA.

    Wierzbicka, Paulina / Abdoul-Carime, Hassan / Kopyra, Janina

    Physical chemistry chemical physics : PCCP

    2024  Volume 26, Issue 11, Page(s) 8761–8766

    Abstract: 5-Fluorouracil is now routinely used in chemo- and radiotherapy. Incorporated within DNA, the molecule is bound to the sugar backbone, forming the 5-fluorouridine sub-unit investigated in the present work. For the clinical usage of the latter, no ... ...

    Abstract 5-Fluorouracil is now routinely used in chemo- and radiotherapy. Incorporated within DNA, the molecule is bound to the sugar backbone, forming the 5-fluorouridine sub-unit investigated in the present work. For the clinical usage of the latter, no information exists on the mechanisms that control the radiosensitizing effect at the molecular level. As low energy (< 12 eV) electrons are abundantly produced along the radiation tracks during cancer treatment using beams of high energy particles, we study how these ballistic secondary electrons damage the sensitizing molecule. The salient result from our study shows that the
    MeSH term(s) Electrons ; DNA/chemistry ; Radiation-Sensitizing Agents/chemistry ; DNA Damage ; Thymidine ; Fluorouracil ; Uridine/analogs & derivatives
    Chemical Substances 5-fluorouridine (4K0M952561) ; DNA (9007-49-2) ; Radiation-Sensitizing Agents ; Thymidine (VC2W18DGKR) ; Fluorouracil (U3P01618RT) ; Uridine (WHI7HQ7H85)
    Language English
    Publishing date 2024-03-13
    Publishing country England
    Document type Journal Article
    ZDB-ID 1476244-4
    ISSN 1463-9084 ; 1463-9076
    ISSN (online) 1463-9084
    ISSN 1463-9076
    DOI 10.1039/d3cp04745h
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Fragmentation of the DNA Lesion 8-oxo-Guanine by Low-Energy Electrons.

    Vetritti, Leonardo / Kopyra, Janina / Wierzbicka, Paulina / Varella, Márcio T do N

    The journal of physical chemistry. A

    2023  Volume 127, Issue 36, Page(s) 7470–7478

    Abstract: 8-oxo-Guanine is a mutagenic lesion produced by reactions involving reactive oxygen species and guanine in DNA. Its production induces mispairing between the canonical nucleobases during DNA replication such that various types of cancers are associated ... ...

    Abstract 8-oxo-Guanine is a mutagenic lesion produced by reactions involving reactive oxygen species and guanine in DNA. Its production induces mispairing between the canonical nucleobases during DNA replication such that various types of cancers are associated with the DNA lesion. Since radiation therapy is used in some cases, the interaction of low-energy electrons with 8-oxo-guanine can in turn produce other reactive species, which in principle could have either a detrimental or protective effect on the organism. Motivated by these facts, we report a comparative experimental study of electron-induced fragmentation of guanine and 8-oxo-guanine, along with a theoretical study of the π* shape resonances and bound anion states, which may trigger those dissociation reactions. The electron-induced fragmentation of 8-oxo-guanine is remarkably distinct from the native form. More complex reactions were observed for the oxidized species, which may produce several anion fragments at very low energies (∼0 eV). The dehydrogenated parent anion, which is already a minor fragment in guanine, was completely suppressed in 8-oxo-guanine. The calculated thermodynamical thresholds also suggest that NH
    MeSH term(s) Electrons ; DNA ; Guanine ; Mutagenesis ; Reactive Oxygen Species
    Chemical Substances DNA (9007-49-2) ; Guanine (5Z93L87A1R) ; Reactive Oxygen Species
    Language English
    Publishing date 2023-09-03
    Publishing country United States
    Document type Journal Article
    ISSN 1520-5215
    ISSN (online) 1520-5215
    DOI 10.1021/acs.jpca.3c03704
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Energy-Selective Decomposition of Organometallic Compounds by Slow Electrons: The Case of Chloro(dimethyl sulfide)gold(I).

    Kopyra, Janina / Rabilloud, Franck / Wierzbicka, Paulina / Abdoul-Carime, Hassan

    The journal of physical chemistry. A

    2021  Volume 125, Issue 4, Page(s) 966–972

    Abstract: Gold-containing compounds offer many applications in nanoscale materials science, and electron-beam methods are versatile for shaping nanostructures. In this study, we report the energy-selective fragmentation of chloro(dimethyl sulfide)gold(I) (ClAuS( ... ...

    Abstract Gold-containing compounds offer many applications in nanoscale materials science, and electron-beam methods are versatile for shaping nanostructures. In this study, we report the energy-selective fragmentation of chloro(dimethyl sulfide)gold(I) (ClAuS(CH
    Language English
    Publishing date 2021-01-25
    Publishing country United States
    Document type Journal Article
    ISSN 1520-5215
    ISSN (online) 1520-5215
    DOI 10.1021/acs.jpca.0c09988
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Impact of autofluorescence for detection of parathyroid glands during thyroidectomy on postoperative parathyroid hormone levels: parallel multicentre randomized clinical trial.

    Bergenfelz, Anders / Barczynski, Marcin / Heie, Anette / Muth, Andreas / Passler, Christian / Schneider, Max / Wierzbicka, Paulina / Konturek, Alexander / Brauckhoff, Katrin / Elf, Anna-Karin / Dahlberg, Jakob / Hermann, Michael

    The British journal of surgery

    2023  Volume 110, Issue 12, Page(s) 1824–1833

    Abstract: Background: Techniques for autofluorescence have been introduced to visualize the parathyroid glands during surgery and to reduce hypoparathyroidism after thyroidectomy.: Methods: This parallel multicentre RCT investigated the use of Fluobeam® LX to ... ...

    Abstract Background: Techniques for autofluorescence have been introduced to visualize the parathyroid glands during surgery and to reduce hypoparathyroidism after thyroidectomy.
    Methods: This parallel multicentre RCT investigated the use of Fluobeam® LX to visualize the parathyroid glands by autofluorescence during total thyroidectomy compared with no use. There was no restriction on the indication for surgery. Patients were randomized 1 : 1 and were blinded to the group allocation. The hypothesis was that autofluorescence enables identification and protection of the parathyroid glands during thyroidectomy. The primary endpoint was the rate of low parathyroid hormone (PTH) levels the day after surgery.
    Results: Some 535 patients were randomized, and 486 patients received an intervention according to the study protocol, 246 in the Fluobeam® LX group and 240 in the control group. Some 64 patients (26.0 per cent) in the Fluobeam® LX group and 77 (32.1 per cent) in the control group had low levels of PTH after thyroidectomy (P = 0.141; relative risk (RR) 0.81, 95 per cent c.i. 0.61 to 1.07). Subanalysis of 174 patients undergoing central lymph node clearance showed that 15 of 82 (18 per cent) in the Fluobeam® LX group and 31 of 92 (33 per cent) in the control group had low levels of PTH on postoperative day 1 (P = 0.021; RR 0.54, 0.31 to 0.93). More parathyroid glands were identified during operation in patients who had surgery with Fluobeam® LX, and fewer parathyroid glands in the surgical specimen on definitive histopathology. No specific harm related to the use of Fluobeam® LX was reported.
    Conclusion: The use of autofluorescence during thyroidectomy did not reduce the rate of low PTH levels on postoperative day 1 in the whole group of patients. It did, however, reduce the rate in a subgroup of patients. Registration number: NCT04509011 (http://www.clinicaltrials.gov).
    MeSH term(s) Humans ; Parathyroid Glands/surgery ; Thyroidectomy/adverse effects ; Thyroidectomy/methods ; Parathyroid Hormone ; Hypoparathyroidism/etiology ; Hypoparathyroidism/prevention & control ; Lymph Nodes ; Postoperative Complications/etiology ; Postoperative Complications/prevention & control ; Postoperative Complications/surgery ; Hypocalcemia/etiology
    Chemical Substances Parathyroid Hormone
    Language English
    Publishing date 2023-09-27
    Publishing country England
    Document type Randomized Controlled Trial ; Multicenter Study ; Journal Article
    ZDB-ID 2985-3
    ISSN 1365-2168 ; 0263-1202 ; 0007-1323 ; 1355-7688
    ISSN (online) 1365-2168
    ISSN 0263-1202 ; 0007-1323 ; 1355-7688
    DOI 10.1093/bjs/znad278
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    Uk I Zs.66: Show issues Location:
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  5. Article ; Online: Experimental and Theoretical Studies of Dissociative Electron Attachment to Metabolites Oxaloacetic and Citric Acids.

    Kopyra, Janina / Wierzbicka, Paulina / Tulwin, Adrian / Thiam, Guillaume / Bald, Ilko / Rabilloud, Franck / Abdoul-Carime, Hassan

    International journal of molecular sciences

    2021  Volume 22, Issue 14

    Abstract: In this contribution the dissociative electron attachment to metabolites found in aerobic organisms, namely oxaloacetic and citric acids, was studied both experimentally by means of a crossed-beam setup and theoretically through density functional theory ...

    Abstract In this contribution the dissociative electron attachment to metabolites found in aerobic organisms, namely oxaloacetic and citric acids, was studied both experimentally by means of a crossed-beam setup and theoretically through density functional theory calculations. Prominent negative ion resonances from both compounds are observed peaking below 0.5 eV resulting in intense formation of fragment anions associated with a decomposition of the carboxyl groups. In addition, resonances at higher energies (3-9 eV) are observed exclusively from the decomposition of the oxaloacetic acid. These fragments are generated with considerably smaller intensities. The striking findings of our calculations indicate the different mechanism by which the near 0 eV electron is trapped by the precursor molecule to form the transitory negative ion prior to dissociation. For the oxaloacetic acid, the transitory anion arises from the capture of the electron directly into some valence states, while, for the citric acid, dipole- or multipole-bound states mediate the transition into the valence states. What is also of high importance is that both compounds while undergoing DEA reactions generate highly reactive neutral species that can lead to severe cell damage in a biological environment.
    MeSH term(s) Anions/chemistry ; Anions/metabolism ; Citric Acid/chemistry ; Citric Acid/metabolism ; Electrons ; Gases/chemistry ; Models, Theoretical ; Oxaloacetic Acid/chemistry ; Oxaloacetic Acid/metabolism ; Quantum Theory
    Chemical Substances Anions ; Gases ; Citric Acid (2968PHW8QP) ; Oxaloacetic Acid (2F399MM81J)
    Language English
    Publishing date 2021-07-18
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2019364-6
    ISSN 1422-0067 ; 1422-0067 ; 1661-6596
    ISSN (online) 1422-0067
    ISSN 1422-0067 ; 1661-6596
    DOI 10.3390/ijms22147676
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  6. Article: Current overview of extrinsic and intrinsic factors in etiology and progression of inflammatory bowel diseases.

    Sobczak, Marta / Fabisiak, Adam / Murawska, Natalia / Wesołowska, Ewelina / Wierzbicka, Paulina / Wlazłowski, Marcin / Wójcikowska, Marta / Zatorski, Hubert / Zwolińska, Marta / Fichna, Jakub

    Pharmacological reports : PR

    2014  Volume 66, Issue 5, Page(s) 766–775

    Abstract: Inflammatory bowel diseases (IBD) are chronic, relapsing disorders affecting gastrointestinal (GI) tract and associated with intestinal mucosa damage and inflammation. The principal therapeutic goals in IBD include control of the intestinal inflammation ... ...

    Abstract Inflammatory bowel diseases (IBD) are chronic, relapsing disorders affecting gastrointestinal (GI) tract and associated with intestinal mucosa damage and inflammation. The principal therapeutic goals in IBD include control of the intestinal inflammation and treatment of the major symptoms, mainly abdominal pain and diarrhea. Current therapeutic strategies for IBD rely on the use of non-specific anti-inflammatory agents and immunosuppressive drugs (e.g. aminosalicylates, monoclonal antibodies, and antibiotics), which cause severe side effects, and - in a significant number of patients - do not induce long-term benefits. In this review, we summarize the epidemiology and the most important risk factors of IBD, including genetic, immunological and environmental. Our main focus is to discuss pharmacological targets for current and future treatments of IBD.
    MeSH term(s) Abdominal Pain/drug therapy ; Abdominal Pain/etiology ; Animals ; Anti-Inflammatory Agents/adverse effects ; Anti-Inflammatory Agents/therapeutic use ; Diarrhea/drug therapy ; Diarrhea/etiology ; Disease Progression ; Drug Design ; Genetic Predisposition to Disease ; Humans ; Immunosuppressive Agents/adverse effects ; Immunosuppressive Agents/therapeutic use ; Inflammatory Bowel Diseases/drug therapy ; Inflammatory Bowel Diseases/epidemiology ; Inflammatory Bowel Diseases/physiopathology ; Risk Factors
    Chemical Substances Anti-Inflammatory Agents ; Immunosuppressive Agents
    Language English
    Publishing date 2014-04-29
    Publishing country Switzerland
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 2186248-5
    ISSN 1734-1140
    ISSN 1734-1140
    DOI 10.1016/j.pharep.2014.04.005
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    Zs.A 861: Show issues Location:
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