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Advances in rectal cancer: Real-world evidence suggests limited gains in prognosis for elderly patients. Cancer Epidemiol 2023; 86:102440. [PMID: 37572415 DOI: 10.1016/j.canep.2023.102440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 07/26/2023] [Accepted: 08/07/2023] [Indexed: 08/14/2023]
Abstract
BACKGROUND Rectal cancer treatment has improved considerably due to the introduction of total meso-rectal excision, radio-chemotherapy, and high-resolution imaging. The aim of this observational cohort study was to quantify the effectiveness of these advances using high-quality data from a representative cohort of patients. METHODS 20 281 non-metastasized cases retrieved from the Munich Cancer Registry database were divided into three time periods corresponding to before (1988-1997), partial (1998-2007), and full implementation (2008-2019) of clinical advances. Early-onset (<50 yrs.), middle-aged, elderly patient subgroups (> 70 yrs.) were compared. The overall effectiveness of evidence-based guideline adherence was also examined. RESULTS Median survival improved by 1.5 yrs. from the first to the last time period. Relative survival increased from 74.9% (5-yr 95%CI[73.3 - 76.6]) to 79.2% (95%CI[77.8 - 80.5]). The incidence of locoregional recurrences was reduced dramatically by more than half (5-yr 17.7% (95%CI[16.5 - 18.8]); 6.7% (95%CI[6.1 - 7.3])). Gains in 5-yr relative survival were limited to early-onset and middle-aged patients with no significant improvement seen in elderly patients (Female 68.6% [63.9 - 73.3] to 67.6% [64.0 - 71.2]; Male 71.7% [65.9 - 77.4] to 74.0% [70.8 - 77.2]). CONCLUSIONS Real-world evidence suggests that recent treatment advances have lead to an increase in prognosis for rectal cancer patients. However, more effort should be made to improve the implementation of new developments in elderly patients. Especially considering, that these cases represent a growing majority of diagnosed patients.
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Stereotactic radiosurgery and radiotherapy for resected brain metastases: current pattern of care in the Radiosurgery and Stereotactic Radiotherapy Working Group of the German Association for Radiation Oncology (DEGRO). Strahlenther Onkol 2022; 198:919-925. [PMID: 36006436 DOI: 10.1007/s00066-022-01991-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 07/17/2022] [Indexed: 11/25/2022]
Abstract
PURPOSE Preoperative stereotactic radiosurgery (SRS) of brain metastases may achieve similar local control and better leptomeningeal control rates than postoperative fractionated stereotactic radiotherapy (FSRT) in patients treated with elective metastasectomy. To plan a multicentre trial of preoperative SRS compared with postoperative FSRT, a survey of experts was conducted to determine current practice. METHODS A survey with 15 questions was distributed to the DEGRO Radiosurgery and Stereotactic Radiotherapy Working Group. Participants were asked under what circumstances they offered SRS, FSRT, partial and/or whole brain radiotherapy before or after resection of a brain metastasis, as well as the feasibility of preoperative stereotactic radiosurgery and neurosurgical resection within 6 days. RESULTS Of 25 participants from 24 centres, 22 completed 100% of the questions. 24 respondents were radiation oncologists and 1 was a neurosurgeon. All 24 centres have one or more dedicated radiosurgery platform and all offer postoperative FSRT. Preoperative SRS is offered by 4/24 (16.7%) centres, and 9/24 (37.5%) sometimes recommend single-fraction postoperative SRS. Partial brain irradiation is offered by 8/24 (33.3%) centres and 12/24 (50%) occasionally recommend whole-brain irradiation. Two centres are participating in clinical trials of preoperative SRS. SRS techniques and fractionation varied between centres. CONCLUSION All responding centres currently offer postoperative FSRT after brain metastasectomy. Approximately one third offer single-fraction postoperative SRS and four already perform preoperative SRS. With regard to potential co-investigators, 18 were identified for the PREOP‑2 multicentre trial, which will randomise between preoperative SRS and postoperative FSRT.
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Improvement of functional outcome for patients with newly diagnosed grade 2 or 3 gliomas with co-deletion of 1p/19q - IMPROVE CODEL: the NOA-18 trial. BMC Cancer 2022; 22:645. [PMID: 35692047 PMCID: PMC9190129 DOI: 10.1186/s12885-022-09720-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 05/30/2022] [Indexed: 12/05/2022] Open
Abstract
Background Given the young age of patients with CNS WHO grade 2 and 3 oligodendrogliomas and the relevant risk of neurocognitive, functional, and quality-of-life impairment with the current aggressive standard of care treatment, chemoradiation with PCV, of the tumour located in the brain optimizing care is the major challenge. Methods NOA-18 aims at improving qualified overall survival (qOS) for adult patients with CNS WHO grade 2 and 3 oligodendrogliomas by randomizing between standard chemoradiation with up to six six-weekly cycles with PCV and six six-weekly cycles with lomustine and temozolomide (CETEG) (n = 182 patients per group accrued over 4 years) thereby delaying radiotherapy and adding the chemoradiotherapy concept at progression after initial radiation-free chemotherapy, allowing for effective salvage treatment and delaying potentially deleterious side effects. QOS represents a new concept and is defined as OS without functional and/or cognitive and/or quality of life deterioration regardless of whether tumour progression or toxicity is the main cause. The primary objective is to show superiority of an initial CETEG treatment followed by partial brain radiotherapy (RT) plus PCV (RT-PCV) at progression over partial brain radiotherapy (RT) followed by procarbazine, lomustine, and vincristine (PCV) chemotherapy (RT-PCV) and best investigators choice (BIC) at progression for sustained qOS. An event concerning a sustained qOS is then defined as a functional and/or cognitive and/or quality of life deterioration after completion of primary therapy on two consecutive study visits with an interval of 3 months, tolerating a deviation of at most 1 month. Assessments are done with a 3-monthly MRI, assessment of the NANO scale, HRQoL, and KPS, and annual cognitive testing. Secondary objectives are evaluation and comparison of the two groups regarding secondary endpoints (short-term qOS, PFS, OS, complete and partial response rate). The trial is planned to be conducted at a minimum of 18 NOA study sites in Germany. Discussion qOS represents a new concept. The present NOA trial aims at showing the superiority of CETEG plus RT-PCV over RT-PCV plus BIC as determined at the level of OS without sustained functional deterioration for all patients with oligodendroglioma diagnosed according to the most recent WHO classification. Trial registration Clinicaltrials.govNCT05331521. EudraCT 2018–005027-16.
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MO-0803 External Validation of NTCP-models for Acute Coronary Events after Breast Cancer Radiotherapy. Radiother Oncol 2022. [DOI: 10.1016/s0167-8140(22)02439-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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THE LINE FOCUS X-RAY TUBE: AN X-RAY SOURCE FOR FLASH AND SPATIALLY FRACTIONATED RADIATION THERAPY. Phys Med 2022. [DOI: 10.1016/s1120-1797(22)01595-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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RACE IT - A prospective, single arm, multicenter, phase II-trial to assess safety and efficacy of preoperative RAdiation therapy before radical CystEctomy combined with ImmunoTherapy in locally advanced urothelial carcinoma of the bladder (AB 65/18). Eur Urol 2022. [DOI: 10.1016/s0302-2838(22)00417-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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RADIOBIOLOGICAL MECHANISMS IN MICROBEAM RADIATION THERAPY (MRT). Phys Med 2022. [DOI: 10.1016/s1120-1797(22)01623-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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PH-0439 An innovative strategy in cancer treatment: Proton minibeam radiation therapy. Radiother Oncol 2021. [DOI: 10.1016/s0167-8140(21)07330-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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PO-1169: Influence of localisation of PSMA-positive oligo-metastases on efficacy of metastasis-directed EBRT. Radiother Oncol 2020. [DOI: 10.1016/s0167-8140(21)01187-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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PO-1087 The interaction between miR-221 overexpression and radiosensitivity in mamma carcinoma cell lines. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)31507-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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EP-1522 Radiotherapy with or without antihormonal therapy for PSMA-positive oligorecurrent prostate cancer. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)31942-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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PO-0861 Analysis of nodal and prostatic bed RT in oligorecurrent PC patients treated with PSMA-PETguided RT. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)31281-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Radiotherapy-induced cardiotoxicity in breast cancer patients: New approaches of early detection and prediction based on cardiac imaging and circulating biomarkers (European MEDIRAD EARLY-HEART study). ARCHIVES OF CARDIOVASCULAR DISEASES SUPPLEMENTS 2019. [DOI: 10.1016/j.acvdsp.2018.10.275] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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PO-1047: Cellular responses to focused low LET proton irradiation. Radiother Oncol 2018. [DOI: 10.1016/s0167-8140(18)31357-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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EP-1596: Follow-up of prostate cancer patients receiving 68Ga-PSMA-PET guided dose escalation radiotherapy. Radiother Oncol 2018. [DOI: 10.1016/s0167-8140(18)31905-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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EP-1219: Dosimetric Comparison of Proton RT with Standard of Care Photon RT Techniques in CNS Tumors. Radiother Oncol 2018. [DOI: 10.1016/s0167-8140(18)31529-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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EP-1410: Comparison of neoadjuvant chemoradiation with carboplatin/paclitaxel or CDDP/5-FU for esophageal SCC. Radiother Oncol 2018. [DOI: 10.1016/s0167-8140(18)31719-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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OC-0324: Immune contexture in SCCHN and outcome after chemoradiotherapy in an uni- and multicentric cohort. Radiother Oncol 2018. [DOI: 10.1016/s0167-8140(18)30634-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Design and Commissioning of a Three-Barrel Shattered Pellet Injector for DIII-D Disruption Mitigation Studies. FUSION SCIENCE AND TECHNOLOGY 2017. [DOI: 10.1080/15361055.2017.1333854] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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EP-1418: RandOmized Study Exploring the combination of radioTherapy with Two types of Acupuncture treatment. Radiother Oncol 2017. [DOI: 10.1016/s0167-8140(17)31853-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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PO-1019: Mobile Oncology: Survey with Healthcare Professionals about Telemedicine, mHealth and mobile Apps. Radiother Oncol 2017. [DOI: 10.1016/s0167-8140(17)31455-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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EP-1110: Evaluation of [18F]FET-PET and MRI assessed recurrence pattern in patients with high-grade glioma. Radiother Oncol 2017. [DOI: 10.1016/s0167-8140(17)31546-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract P6-10-02: MHC-II positive breast tumors are more immunogenic and may preferentially select for LAG-3-positive tumor immune infiltrates. Cancer Res 2017. [DOI: 10.1158/1538-7445.sabcs16-p6-10-02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Lymphocyte-activation gene 3 (LAG-3) is a T-cell checkpoint regulator and a current target in immunotherapy trials. LAG-3's main ligand is MHC class II (MHC-II), to which it binds with higher affinity than CD4. Binding of LAG3 to MHC-II antigen-presenting cells negatively regulates cellular proliferation, activation, and homeostasis of T cells, similarly to CTLA-4 and PD-1, suggesting that antibodies targeting LAG-3 may demonstrate similar anti-tumor immune effects.
Hypothesis: We recently reported an association of MHC-II on tumor cells and its involvement in mediating sensitivity to PD-1/PD-L1 monoclonal antibodies. MHC-II demonstrates a strong bimodal expression pattern on tumor cells from a variety of tissues, including those of the breast. In breast cancer patients, tumor-specific MHC-II expression on TNBCs is correlated with a 'hot' immune environment. We hypothesized that 1) MHC-II expression may drive potent anti-tumor immune responses and 2) MHC-II-positive tumors that generate immunotolerance may develop a specific immune checkpoint dependency on LAG-3, since LAG-3 is the inhibitory receptor for MHC-II-mediated antigen presentation.
Methods: To determine the functionality of MHC-II in driving anti-tumor immune responses, we constitutively expressed the MHC-II master regulator CIITA in MMTV-neu mouse tumor cells and determined their ability to form tumors in immunocompetent syngeneic hosts. To evaluate the association of MHC-II+ tumors with LAG-3 expression, we evaluated LAG-3-positivity by immunohistochemistry (IHC) in lymphocytic infiltrates in a series of 111 post-NAC TNBC specimens from patients with residual disease remaining after presurgical chemotherapy. Tumor-infiltrating lymphocytes (TILs) were scored by H&E, PD-L1 and MHC-II (HLA-DR) were scored in the stroma and tumor compartments using automated quantitative immunofluorescence (AQUA).
Results: Enforced expression of MHC-II via constitutive expression of CIITA caused rejection in 60% of mice, while only 11% of mice rejected MMTV-neu tumors expressing the vector control (Fisher's exact p=0.04). All rejecting mice were immune to rechallenge with parental (non-CIITA-expressing) MMTV-neu cells, suggesting a memory effector response.
Clinically, 11/102 patients (10.8%) had LAG-3+ immune cells in their tumor. LAG-3+ tumors were strongly correlated with MHC-II positivity in tumor cells (p<0.0001). Presence of LAG-3+ cells also correlated strongly with overall TILs (p<0.0001), and PD-L1 expression on TILs (p<0.02). Since the likelihood of identifying LAG3+ lymphocytes is confounded by the inclusion of poorly-infiltrated tumors, we performed a subset analysis on only those tumors with substantial TILs (>20%). When this subset was analyzed, LAG-3 positivity retained its association with tumor MHC-II expression (p=0.0001), while the association of LAG-3 with stromal PD-L1 was reduced below the level of significance (p=0.052).
Conclusions: MHC-II expression causes increased immune activation in breast cancers, consistent with our previous findings. MHC-II positivity in breast tumors may identify a population with preferential dependence on the LAG-3 checkpoint, which may be important for future immunotherapy trials.
Citation Format: Balko JM, Loi S, Giltnane JM, Combs S, Estrada MV, Sanchez V, Rimm D, Sanders ME, Salgado R, Gomez H, Johnson DB. MHC-II positive breast tumors are more immunogenic and may preferentially select for LAG-3-positive tumor immune infiltrates [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-10-02.
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OC-0445: Patterns of care and outcome analysis of SBRT for liver metastases - a DEGRO database initiative. Radiother Oncol 2016. [DOI: 10.1016/s0167-8140(16)31694-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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EP-1073: Validation of the Heidelberg prognostic reirradiation score in an independent patient cohort. Radiother Oncol 2014. [DOI: 10.1016/s0167-8140(15)31191-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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SP-0327 Current challenges in radiobiology. Radiother Oncol 2014. [DOI: 10.1016/s0167-8140(15)30432-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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4D Treatment Dose Reconstruction for Scanned Ion Beam Therapy. Int J Radiat Oncol Biol Phys 2013. [DOI: 10.1016/j.ijrobp.2013.06.472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Computational design of protein-small molecule interfaces. J Struct Biol 2013; 185:193-202. [PMID: 23962892 DOI: 10.1016/j.jsb.2013.08.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 07/13/2013] [Accepted: 08/07/2013] [Indexed: 02/06/2023]
Abstract
The computational design of proteins that bind small molecule ligands is one of the unsolved challenges in protein engineering. It is complicated by the relatively small size of the ligand which limits the number of intermolecular interactions. Furthermore, near-perfect geometries between interacting partners are required to achieve high binding affinities. For apolar, rigid small molecules the interactions are dominated by short-range van der Waals forces. As the number of polar groups in the ligand increases, hydrogen bonds, salt bridges, cation-π, and π-π interactions gain importance. These partial covalent interactions are longer ranged, and additionally, their strength depends on the environment (e.g. solvent exposure). To assess the current state of protein-small molecule interface design, we benchmark the popular computer algorithm Rosetta on a diverse set of 43 protein-ligand complexes. On average, we achieve sequence recoveries in the binding site of 59% when the ligand is allowed limited reorientation, and 48% when the ligand is allowed full reorientation. When simulating the redesign of a protein binding site, sequence recovery among residues that contribute most to binding was 52% when slight ligand reorientation was allowed, and 27% when full ligand reorientation was allowed. As expected, sequence recovery correlates with ligand displacement.
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WE-G-500-06: Offline PET/CT Imaging of Scanned Proton and Carbon Ion Beams: Initial Clinical Experience for Different Tumour Sites. Med Phys 2013. [DOI: 10.1118/1.4815639] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Diffusions-gewichtete Bildgebung (DWI) in Kombination mit Dual-Energy CT (DECT) im Therapiemonitoring nach Schwerionentherapie bei Patienten mit hepatozellulärem Karzinom (HCC). ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Long-term Results and Patient Self-reported Outcome in Patients Treated With Fractionated Stereotactic Radiation Therapy (FSRT) or Stereotactic Radiosurgery (SRS) for Acoustic Neuroma. Int J Radiat Oncol Biol Phys 2012. [DOI: 10.1016/j.ijrobp.2012.07.516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Comparison of Photon Versus Carbon Irradiation in Pancreatic Cancer. Int J Radiat Oncol Biol Phys 2012. [DOI: 10.1016/j.ijrobp.2012.07.1832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Exploring Symmetry as an Avenue to the Computational Design of Large Protein Domains. J Am Chem Soc 2011. [DOI: 10.1021/ja210593m] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
It has been demonstrated previously that symmetric, homodimeric proteins are energetically favored, which explains their abundance in nature. It has been proposed that such symmetric homodimers underwent gene duplication and fusion to evolve into protein topologies that have a symmetric arrangement of secondary structure elements--"symmetric superfolds". Here, the ROSETTA protein design software was used to computationally engineer a perfectly symmetric variant of imidazole glycerol phosphate synthase and its corresponding symmetric homodimer. The new protein, termed FLR, adopts the symmetric (βα)(8) TIM-barrel superfold. The protein is soluble and monomeric and exhibits two-fold symmetry not only in the arrangement of secondary structure elements but also in sequence and at atomic detail, as verified by crystallography. When cut in half, FLR dimerizes readily to form the symmetric homodimer. The successful computational design of FLR demonstrates progress in our understanding of the underlying principles of protein stability and presents an attractive strategy for the in silico construction of larger protein domains from smaller pieces.
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Effect of Carbon Ion Irradiation on Human Papillomavirus (HPV) 16 Positive Cervical Keratinocytes. Int J Radiat Oncol Biol Phys 2011. [DOI: 10.1016/j.ijrobp.2011.06.1296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Generation and Validation of a Prognostic Score to Predict Outcome after Re-irradiation of Recurrent Glioma. Int J Radiat Oncol Biol Phys 2011. [DOI: 10.1016/j.ijrobp.2011.06.466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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A conserved asparagine residue in transmembrane segment 1 (TM1) of serotonin transporter dictates chloride-coupled neurotransmitter transport. J Biol Chem 2011; 286:30823-30836. [PMID: 21730057 DOI: 10.1074/jbc.m111.250308] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Na(+)- and Cl(-)-dependent uptake of neurotransmitters via transporters of the SLC6 family, including the human serotonin transporter (SLC6A4), is critical for efficient synaptic transmission. Although residues in the human serotonin transporter involved in direct Cl(-) coordination of human serotonin transport have been identified, the role of Cl(-) in the transport mechanism remains unclear. Through a combination of mutagenesis, chemical modification, substrate and charge flux measurements, and molecular modeling studies, we reveal an unexpected role for the highly conserved transmembrane segment 1 residue Asn-101 in coupling Cl(-) binding to concentrative neurotransmitter uptake.
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Y95 and E444 interaction required for high-affinity S-citalopram binding in the human serotonin transporter. ACS Chem Neurosci 2011; 2:75-81. [PMID: 22778858 DOI: 10.1021/cn100066p] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Accepted: 10/11/2010] [Indexed: 11/28/2022] Open
Abstract
The human serotonin (5-hydroxytryptamine, 5-HT) transporter (hSERT) is responsible for the reuptake of 5-HT following synaptic release, as well as for import of the biogenic amine into several non-5-HT synthesizing cells including platelets. The antidepressant citalopram blocks SERT and thereby inhibits the transport of 5-HT. To identify key residues establishing high-affinity citalopram binding, we have built a comparative model of hSERT and Drosophila melanogaster SERT (dSERT) based on the Aquifex aeolicus leucine transporter (LeuT(Aa)) crystal structure. In this study, citalopram has been docked into the homology model of hSERT and dSERT using RosettaLigand. Our models reproduce the differential binding affinities for the R- and S-isomers of citalopram in hSERT and the impact of several hSERT mutants. Species-selective binding affinities for hSERT and dSERT also can be reproduced. Interestingly, the model predicts a hydrogen bond between E444 in transmembrane domain 8 (TM8) and Y95 in TM1 that places Y95 in a downward position, thereby removing Y95 from a direct interaction with S-citalopram. Mutation of E444D results in a 10-fold reduced binding affinity for S-citalopram, supporting the hypothesis that Y95 and E444 form a stabilizing interaction in the S-citalopram/hSERT complex.
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P1.075 Effects of non-contact boxing training on spatiotemporal gait parameters in persons with Parkinson's disease: a case series. Parkinsonism Relat Disord 2009. [DOI: 10.1016/s1353-8020(09)70197-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Impact of the New WHO Classification on Decision-making for Radiation Therapy in Patients with Atypical and Anaplastic Meningiomas. Int J Radiat Oncol Biol Phys 2009. [DOI: 10.1016/j.ijrobp.2009.07.309] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Somatosensory cortical activation identified by functional MRI in preterm and term infants. Neuroimage 2009; 49:2063-71. [PMID: 19854281 DOI: 10.1016/j.neuroimage.2009.10.038] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Revised: 09/03/2009] [Accepted: 10/13/2009] [Indexed: 10/20/2022] Open
Abstract
Functional MRI (fMRI) has not previously been used systematically to investigate brain function in preterm infants. We here describe statistically robust and reproducible fMRI results in this challenging subject group using a programmable somatosensory stimulus synchronized with MR image acquisition which induced well-localized positive blood oxygen level dependent (BOLD) responses contralateral to the side of the stimulation in: 11 preterm infants (median post menstrual age 33 weeks and 4 days, range 29+1 to 35+3); 6 control infants born at term gestational age; and 18 infants born preterm (median gestational age at birth 30 weeks and 5 days, range 25+4 to 36+0) but studied at term corrected gestational age. Bilateral signals were identified in 8 of the ex-preterm infants at term age. Anatomical confirmation of appropriate activations was provided with diffusion tensor imaging (DTI) based tractography which identified connecting pathways from the regions of activation through the ipsilateral corticospinal tracts and posterior limb of the internal capsule. These results demonstrate that it is possible to reliably identify positive BOLD signals in the infant brain and that fMRI techniques can also be applied in the study of preterm infants.
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Mass transfer in long pellet guiding systems at ASDEX upgrade and JET. FUSION ENGINEERING AND DESIGN 2003. [DOI: 10.1016/s0920-3796(03)00226-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Abstract
Ascorbic acid positively affects the synthesis of collagen, the most abundant extracellular protein. The mechanism by which ascorbate mediates the increased synthesis is debated. One recent hypothesis suggests that ascorbic acid induces an increase in lipid peroxidation and that this increase, in some manner, up-regulates collagen gene expression. Evidence is presented that indicate increases in lipid peroxidation [thiobarbituric acid (TBA)-reactive material] is coincidental to collagen increases in ascorbate-treated cells, not a causal factor. Thus, cell impermeable iron chelators totally abolish ascorbate-mediated lipid peroxidation but do not affect collagen synthesis in the least. Decreases in TBA-reactive products seen at higher ascorbate levels (indicative of the well known pro- to antioxidant conversion of ascorbate in vitro) are paralleled by decreases in collagen synthesis. The decrease seen in collagen is completely reversed by treatment of the cell cultures with superoxide dismutase and catalase while the measure of lipid peroxidation is unaffected by coincubation with these antioxidant enzymes. Additionally, incubation conditions used to measure ascorbate induction of TBA-reactive material (buffers vs media, adherent vs detached cells) were found to be very important and results support the thesis that lipid peroxidation and collagen synthesis can be dissociated. While these results do not rule out a role for lipid mediators in regulating collagen synthesis at some level, they suggest this mechanism need not be involved for collagen increases seen in ascorbic acid-treated cells.
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Studies on the inhibition of collagen synthesis in fibroblasts treated with paraquat. Arch Biochem Biophys 1993; 306:267-71. [PMID: 8215414 DOI: 10.1006/abbi.1993.1510] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Paraquat (methyl viologen) is an industrial herbicide which upon entering many cell types can be enzymatically reduced and in the presence of oxygen, subsequently generate the superoxide radical anion (O2-). This is its mode of toxicity in many of these cells. In vivo, it has been shown to preferentially accumulate in lung tissue, leading to tissue destruction and marked fibrosis. Collagen accumulation has also been noted in paraquat-treated lung slices in vitro. In studies designed to investigate these effects, it has been found, unexpectedly, that paraquat inhibits collagen synthesis in isolated fibroblasts. This inhibition is not due to overt cellular toxicity nor to inhibition of prolyl hydroxylase (directly or by cofactor depletion). While this effect could be unique to paraquat, it may be relevant to a more generalized role for free radicals in regulating collagen synthesis at the level of the individual cell.
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Abstract
Ultraviolet radiation damage to the skin is due, in part, to the generation of reactive oxygen species. Vitamin C (L-ascorbic acid) functions as a biological co-factor and antioxidant due to its reducing properties. Topical application of vitamin C has been shown to elevate significantly cutaneous levels of this vitamin in pigs, and this correlates with protection of the skin from UVB damage as measured by erythema and sunburn cell formation. This protection is biological and due to the reducing properties of the molecule. Further, we provide evidence that the vitamin C levels of the skin can be severely depleted after UV irradiation, which would lower this organ's innate protective mechanism as well as leaving it at risk of impaired healing after photoinduced damage. In addition, vitamin C protects porcine skin from UVA-mediated phototoxic reactions (PUVA) and therefore shows promise as a broad-spectrum photoprotectant.
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Analysis of idiotypic and anti-idiotypic antibodies as models of receptor and ligand. Clin Chem 1988; 34:1676-80. [PMID: 2901298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Antibodies to small bioactive ligands and peptides may mimic the binding characteristics of the natural receptor; in turn, the anti-idiotypic antibodies generated against the binding sites of such anti-ligand antibodies may mimic some aspects of small bioactive ligands and peptides. Among the several levels of investigation of such antibody-receptor networks are (a) the quantitative structure-activity relationships of ligand binding to antibody as compared with natural receptor; (b) the molecular modeling of antibody-receptor binding sites and the genomic basis for such structures; and (c) the characteristics of the molecular mimicry exhibited by "mimetopes" on anti-idiotypic antibodies. To illustrate the analysis encountered at each of these levels, we discuss here antibody and anti-idiotypic systems that are directed to small neuroactive ligands and their receptors.
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Abstract
Abstract
Antibodies to small bioactive ligands and peptides may mimic the binding characteristics of the natural receptor; in turn, the anti-idiotypic antibodies generated against the binding sites of such anti-ligand antibodies may mimic some aspects of small bioactive ligands and peptides. Among the several levels of investigation of such antibody-receptor networks are (a) the quantitative structure-activity relationships of ligand binding to antibody as compared with natural receptor; (b) the molecular modeling of antibody-receptor binding sites and the genomic basis for such structures; and (c) the characteristics of the molecular mimicry exhibited by "mimetopes" on anti-idiotypic antibodies. To illustrate the analysis encountered at each of these levels, we discuss here antibody and anti-idiotypic systems that are directed to small neuroactive ligands and their receptors.
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Prescription of psychotropic drugs in Eastern Kentucky. THE JOURNAL OF THE KENTUCKY MEDICAL ASSOCIATION 1972; 70:25-7. [PMID: 4400259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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