Publications by authors named "Andrew Sykes"
Dynamic segmental kinematics of the lumbar spine during diagnostic movements.
Front Bioeng Biotechnol
September 2023
Article Synopsis
- - The study focuses on understanding the connection between pain and the complex factors that influence it through segmental-level kinematics, specifically in the lower spine.
- - Using a new marker set with an optical motion capture system, the research measured 3D movements of the lumbar spine in 28 subjects during 17 different diagnostic movements.
- - Key findings revealed differences in segmental velocities during movements and established a baseline for normal lumbar movement patterns, which is essential for detecting abnormal patterns associated with pain.
Article Synopsis
- There is growing interest in hypofractionated radiotherapy for head and neck cancer, but not enough data to establish a consensus on its use.
- This multicenter study examined outcomes in oropharyngeal squamous cell carcinoma patients treated with either standard or accelerated mildly hypofractionated radiotherapy without chemotherapy.
- Results showed no significant differences in locoregional control, overall survival, or swallowing function between the two treatment schedules, suggesting hypofractionated radiotherapy is a viable option for patients who cannot receive chemotherapy.
A highly selective pyridoxal-based chemosensor for the detection of Zn(ii) and application in live-cell imaging; X-ray crystallography of pyridoxal-TRIS Schiff-base Zn(ii) and Cu(ii) complexes.
Anwar Hussain Kadarkaraisamy Mariappan Dawson C Cork Luke D Lewandowski Prem K Shrestha Andrew G Sykes
RSC Adv
October 2021
Article Synopsis
- - A pyridoxal-based chemosensor was developed by combining TRIS and pyridoxal hydrochloride to create a ligand that selectively detects Zn(ii) ions, which was confirmed through various characterization methods.
- - The sensor demonstrated a significant fluorescence turn-on response when detecting zinc, with 12-fold increased intensity and a low detection limit of 2.77 × 10 M, suitable for use in biological contexts.
- - Studies revealed the ligand forms a stable complex with Zn(ii) ions and is easily reversible with EDTA; additionally, a separate copper(ii) complex was made, showing distinct coordination features.
Article Synopsis
- The study aimed to determine if the pretreatment absolute lymphocyte count (ALC) can help identify oropharyngeal squamous cell carcinoma (OPSCC) patients who might benefit from reducing chemotherapy during treatment.
- Researchers analyzed data from nearly 800 patients undergoing treatment, assessing overall survival (OS) and locoregional control (LRC) based on ALC levels.
- Findings suggested that ALC is a significant predictor of OS and indicates how well patients might respond to adding cisplatin chemotherapy, potentially guiding future treatment de-escalation strategies.
Article Synopsis
- * Seven clinicians tested their ability to outline these muscles on CT scans with and without the atlas, revealing that the atlas significantly improved agreement among clinicians.
- * Results showed that the atlas reduced variability in muscle contouring and could serve as a valuable educational resource for clinicians planning radiotherapy for head and neck cancer patients.
Poor survival rates of patients with tumors arising from or disseminating into the brain are attributed to an inability to excise all tumor tissue (if operable), a lack of blood-brain barrier (BBB) penetration of chemotherapies/targeted agents, and an intrinsic tumor radio-/chemo-resistance. Ataxia-telangiectasia mutated (ATM) protein orchestrates the cellular DNA damage response (DDR) to cytotoxic DNA double-strand breaks induced by ionizing radiation (IR). ATM genetic ablation or pharmacological inhibition results in tumor cell hypersensitivity to IR.
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- The study investigates long-term swallowing outcomes in patients with oropharyngeal carcinoma who underwent chemoradiotherapy at two UK centers, aiming to gather patient-reported results and identify influencing factors.
- After excluding patients needing enteral feeding or those with disease relapse, 201 out of 242 eligible patients completed a swallowing inventory two years post-treatment, revealing a median score indicating varying degrees of swallowing function.
- Findings indicate that many patients experience long-term swallowing dysfunction, particularly those with poor pre-treatment diets or who required feeding tubes, highlighting the need for better management strategies in these groups.
Article Synopsis
- This feasibility study explored the connection between radiation doses to the masticatory muscles and the development of trismus (limited jaw movement) in patients undergoing radiotherapy for oral cavity or oropharyngeal cancers.
- A total of 20 patients were measured for maximal inter-incisor distance (MID) before and 6 months after starting treatment, while also considering various factors like age and exercise compliance.
- Results indicated that higher radiation doses to specific muscles were linked to worsening trismus, suggesting that keeping doses below 40 Gy might help reduce this side effect in certain cancer patients.
Purpose: The benefit of adding docetaxel, cisplatin and 5-fluorouracil (TPF) induction chemotherapy to chemoradiotherapy (CRT) in head and neck squamous cell carcinoma (HNSCC) remains uncertain. We aimed to investigate whether ICT is well tolerated when given with prophylactic treatment against predicted adverse effects and which patients benefit most.
Methods: A single-centre audit identified 132 HNSCC patients with stage IVa/b neck node-positive disease, prescribed TPF followed by CRT.
Article Synopsis
- The study investigated the effects of hypofractionated accelerated radiotherapy on T2 glottic cancers, focusing on outcomes and late toxicity.
- It treated 112 patients with a specific dose regimen and reported a 67% overall survival rate and 82% local control after five years.
- The findings suggest that hypofractionated treatments improve local control while maintaining low levels of late toxicity, indicating they should be considered as standard care for early glottic laryngeal cancers.
Article Synopsis
- Infractional anatomical changes can affect how well step-and-shoot IMRT and VMAT deliver radiation doses, but their impact on head and neck cancer has not been thoroughly studied.
- A study involving 10 patients undergoing repeat CT scans analyzed and compared the effectiveness of step-and-shoot IMRT versus VMAT in dose delivery and target coverage.
- Results showed that although both techniques had notable dosimetric changes following the second CT scan, there were no significant differences in plan robustness between IMRT and VMAT for the patients in this study.
Improved selectivity for Pb(II) by sulfur, selenium and tellurium analogues of 1,8-anthraquinone-18-crown-5: synthesis, spectroscopy, X-ray crystallography and computational studies.
Kadarkaraisamy Mariappan Madhubabu Alaparthi Mariah Hoffman Myriam Alcantar Rama Vinothini Balasubramanian Andrew G Sykes
Dalton Trans
July 2015
Article Synopsis
- A series of macrocycles with an anthraquinone unit and cyclic polyheteroether chains were synthesized with sulfur, selenium, and tellurium substitutions for use in fluorescence signaling.
- The new compounds exhibited strong green fluorescence when paired with lead ions (Pb(II)) in acetonitrile, showing better selectivity compared to an oxygen version that also interacted with calcium ions (Ca(II)).
- Studies including UV-Visible, luminescence titrations, and single-crystal X-ray analysis confirmed the formation of 1:1 complexes with Pb(II), while cyclic voltammetry and DFT calculations provided insights into the electrochemical properties and energy levels of the compounds.
Article Synopsis
- The study focused on improving loco-regional control in stage II and III head and neck squamous cell carcinoma using an intensified radiation therapy combined with cetuximab, aiming to minimize late normal tissue toxicity.
- In a phase I/II trial with 27 patients, the treatment was generally well-tolerated, with most experiencing acute toxicities like pain and oral mucositis, but only a few had significant late toxicities after 12 months.
- The results indicated promising survival rates and quality of life outcomes, suggesting that this therapy regimen is both effective and safe for the treatment of HNSCC.
Article Synopsis
- The study analyzes the effectiveness of the Smart Probabilistic Image Contouring Engine (SPICE) for automatically defining organs at risk (OARs) in intensity-modulated radiotherapy (IMRT) for head and neck cancer, noting that manual delineation is time-consuming and varies between observers.! -
- While SPICE was found to be less accurate than manual contouring for delineating important structures like parotid and submandibular glands, it did achieve acceptable accuracy levels but failed to save time or improve efficiency in the process.! -
- The authors conclude that enhancements in the accuracy of automatic segmentation tools like SPICE are necessary before they can be reliably used in clinical settings for treating head and neck cancer patients
Article Synopsis
- - A series of (BMI)3LnCl6 crystals were created using lanthanide chloride (LnCl3) dissolved in an ionic liquid called BMICl, focusing on various lanthanides like Sm, Eu, Dy, Er, and Yb.
- - Crystals with combinations of 5% Sm + 95% Gd and 5% Dy + 95% Gd were grown to study how these elements interact through cross-relaxation.
- - The crystals share a monoclinic structure with specific coordination involving six chloride ions around the lanthanides and nine BMI cations, and their spectral properties indicate they mirror the lanthanide environment present in solution.
Selective fluorescence sensing of copper(II) and water via competing imine hydrolysis and alcohol oxidation pathways sensitive to water content in aqueous acetonitrile mixtures.
Kadarkaraisamy Mariappan Madhubabu Alaparthi Gerald Caple Vinothini Balasubramanian Mariah M Hoffman Andrew G Sykes
Inorg Chem
March 2014
Article Synopsis
- * The system produces intense yellow fluorescence in the presence of copper(II) ions, functioning as a selective fluorescence sensor, while a green-fluorescent intermediate forms in the presence of water.
- * In high-water environments, the reaction pathway shifts, with the oxidation of a secondary alcohol occurring faster than the hydrolysis of the hydrazone, ultimately resulting in the same anthraquinone product; dioxygen also significantly impacts fluorescence emission by quenching it.
Article Synopsis
- - The study investigates the use of sorafenib, a multikinase inhibitor, to treat advanced adenoid cystic carcinoma (ACC), which has poor chemotherapy response rates and limited success with targeted agents.
- - In a phase II trial, 23 patients were treated daily with sorafenib, resulting in median progression-free survival of 11.3 months and overall survival of 19.6 months, with 6-month and 12-month PFS rates of 69.3% and 46.2%.
- - Sorafenib was found to have modest effectiveness in ACC but was associated with significant side effects, leading to the conclusion that it is not recommended for further evaluation based on its limited benefits and high toxicity.
Article Synopsis
- Selective reduction of an anthracenone-quinoline imine derivative using sodium borohydride results in an anthracen-9-ol derivative, confirmed by various spectroscopic methods.
- Introduction of metal ions like Zn(II) and Cu(II) causes significant changes in the compound's properties, with Zn(II) leading to fluorophore formation and Cu(II) prompting color changes and imine hydrolysis.
- This compound acts as both a chemosensor for reversible interactions with Zn(II) and a chemodosimeter for irreversible reactions with Cu(II), requiring the presence of a coordinating Lewis base such as quinoline for effectiveness with Cu(II).
Article Synopsis
- A zinc porphyrin compound with acrylic acid at its meso position has been studied.
- It shows an energy conversion efficiency of 5.1%.
- This suggests it could be a promising and affordable option for use in dye-sensitized solar cells.
Article Synopsis
- - Reduction of imine-anthracenone compounds leads to the formation of secondary alcohols while keeping the external imine group intact.
- - The presence of Zn(II) ions triggers a unique metal-mediated reaction that converts imine compounds into enamine forms.
- - This process introduces a novel fluorescence detection method specifically for Zn(II), which hasn't been documented before.
catena-Poly[1-butyl-3-methyl-imidazolium [[dichlorido(methanol-κO)(propan-2-ol-κO)lanthanate(III)]-di-μ-chlorido]].
Acta Crystallogr Sect E Struct Rep Online
March 2012
Article Synopsis
- - The compound studied is composed of a 1-butyl-3-methyl-imidazolium (BMI(+)) cation and a specific anion featuring a lanthanate ion, which is coordinated with chlorido, methanol, and propan-2-ol molecules.
- - The lanthanum (La(III)) ion has an unusual eight-coordinate structure, connected in chains via chlorine atoms, with additional coordination from methanol and propan-2-ol, leading to unique hydrogen bonding interactions.
- - The arrangement of the anions within the structure forms a special pattern within the triclinic unit cell, centered around the La(2)Cl(2) coordination environment, contributing to the overall stability
Di-μ-pivalato-κO,O':O';κO:O,O'-bis-[(methanol-κO)bis-(2,2,6,6-tetra-methylhepta-ne-3,5-dionato)praseo-dymium(III)].
Acta Crystallogr Sect E Struct Rep Online
November 2011
Article Synopsis
- * The two Pr(III) ions are connected by oxygen atoms from the pivalate anions, maintaining a distance of 4.273 Å between them.
- * There are intra-molecular hydrogen bonds present between the methanol and thd(-) ligands, linking the two symmetry-related Pr(III) ions.