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1.
Laryngoscope Investig Otolaryngol ; 8(4): 895-902, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37621289

ABSTRACT

Objective: Cisplatin forms the backbone of systemic chemotherapy treatment for oropharyngeal squamous cell carcinoma (OPSCC). The ideal cisplatin dosing regimen remains yet to be fully defined for achieving optimal efficacy and toxicity profiles in patients with comorbidity. Methods: We retrospectively reviewed oncologic and toxicity data for patients with OPSCC treated at the Michael E. DeBakey Veterans Affairs Medical Center between 2000 and 2020 who initiated curative intent, definitive chemo-radiation with one of three single agent regimens: high dose (HD) cisplatin, low dose (LD) cisplatin or cetuximab. Results: Patients with HPV-associated tumors and nonsmokers demonstrated improved overall and disease-free survival along with locoregional and distant metastatic control regardless of chemotherapy regimen. Regardless of regimen selection, patients which received a cumulative cisplatin dose ≥200 mg/m2 had a lower rate of distant metastasis. The HD regimen resulted in a greater fraction (75% vs. 50%) of patients receiving a cumulative cisplatin dose ≥200 mg/m2 and a comparable measured toxicity burden compared to the LD regimen. Conclusions: Both HD and LD cisplatin regimens can be safely delivered to a Veteran OPSCC patient population which should allow for straightforward application of conclusions drawn from completed and active clinical trials testing cisplatin regimens. Level of Evidence: 4.

2.
Stem Cell Reports ; 18(3): 636-653, 2023 03 14.
Article in English | MEDLINE | ID: mdl-36827975

ABSTRACT

Ancestral SARS coronavirus-2 (SARS-CoV-2) and variants of concern (VOC) caused a global pandemic with a spectrum of disease severity. The mechanistic explaining variations related to airway epithelium are relatively understudied. Here, we biobanked airway organoids (AO) by preserving stem cell function. We optimized viral infection with H1N1/PR8 and comprehensively characterized epithelial responses to SARS-CoV-2 infection in phenotypically stable AO from 20 different subjects. We discovered Tetraspanin-8 (TSPAN8) as a facilitator of SARS-CoV-2 infection. TSPAN8 facilitates SARS-CoV-2 infection rates independently of ACE2-Spike interaction. In head-to-head comparisons with Ancestral SARS-CoV-2, Delta and Omicron VOC displayed lower overall infection rates of AO but triggered changes in epithelial response. All variants shared highest tropism for ciliated and goblet cells. TSPAN8-blocking antibodies diminish SARS-CoV-2 infection and may spur novel avenues for COVID-19 therapy.


Subject(s)
COVID-19 , Influenza A Virus, H1N1 Subtype , Humans , SARS-CoV-2 , Organoids , Tetraspanins/genetics
3.
bioRxiv ; 2021 Jun 02.
Article in English | MEDLINE | ID: mdl-34100012

ABSTRACT

SARS coronavirus-2 (SARS-CoV-2) is causing a global pandemic with large variation in COVID-19 disease spectrum. SARS-CoV-2 infection requires host receptor ACE2 on lung epithelium, but epithelial underpinnings of variation are largely unknown. We capitalized on comprehensive organoid assays to report remarkable variation in SARS-CoV-2 infection rates of lung organoids from different subjects. Tropism is highest for TUBA- and MUC5AC-positive organoid cells, but levels of TUBA-, MUC5A-, or ACE2- positive cells do not predict infection rate. We identify surface molecule Tetraspanin 8 (TSPAN8) as novel mediator of SARS-CoV-2 infection, which is not downregulated by this specific virus. TSPAN8 levels, prior to infection, strongly correlate with infection rate and TSPAN8-blocking antibodies diminish SARS-CoV-2 infection. We propose TSPAN8 as novel functional biomarker and potential therapeutic target for COVID-19.

4.
Environ Pollut ; 264: 114633, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32388295

ABSTRACT

A study was conducted to quantify the abundance of plastic pollution in the gastrointestinal tracts in birds of prey. Data was collected from all birds retrieved from the Audubon Center for Birds of Prey in central Florida, USA from January to May 2018. Individuals were either dead prior to reaching the Center or died within 24 h of arrival with no food consumed during captivity. Sixty-three individuals representing eight species were dissected to extract the gastrointestinal (GI) tract from the esophagus to the large intestine. Microplastics were found in the GI tracts in all examined species and in all individual birds. The overall mean number (±S.E.) of microplastics for species of bird of prey in central Florida was 11.9 (±2.8), and the overall mean number of microplastics per gram of GI tract tissue was 0.3 (±0.1). A total of 1197 pieces of plastic were recorded. Microfibers accounted for 86% of total plastics followed by microfragments (13%), macroplastics (0.7%) and microbeads (0.3%). Most fibers were either clear or royal blue in color. Micro-Fourier-transform infrared spectroscopy (µ-FTIR) found that processed cellulose was the most common polymer identified in birds (37%), followed by polyethylene terephthalate (16%) and a polymer blend (4:1) of polyamide-6 and poly(ethylene-co-polypropylene) (11%). Two bird species, Buteo lineatus (red-shouldered hawk, n = 28) and Pandion haliaetus (osprey, n = 16), were sufficiently abundant to enable statistical analyses. Microplastics were significantly more abundant per gram in the gastrointestinal tract tissue of B. lineatus, that consumes small mammals, snakes, and amphibians, than in fish-feeding P. haliaetus (ANOVA: p = 0.013). If raptors in terrestrial food webs have higher densities of microplastics than aquatic top predators, then it potentially could be due to a combination of direct intake of plastics and indirect consumption via trophic transfer.


Subject(s)
Gastrointestinal Tract/chemistry , Water Pollutants, Chemical/analysis , Animals , Birds , Environmental Monitoring , Florida , Microplastics , Plastics
6.
AAPS J ; 16(2): 221-5, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24395373

ABSTRACT

The L1 Global Harmonization Team provides recommendations specifically for run acceptance of ligand binding methods used in bioanalysis of macromolecules in support of pharmacokinetics. The team focused on standard curve calibrators and quality controls for use in both pre-study validation and in-study sample analysis, including their preparation and acceptance criteria. The team also considered standard curve editing and the concept of total error.


Subject(s)
Macromolecular Substances/analysis , Practice Guidelines as Topic , Validation Studies as Topic , Quality Control
7.
Oncol Rep ; 24(4): 1049-58, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20811688

ABSTRACT

Angiogenesis inhibitors may enhance the effects of low dose (metronomic) chemotherapy. However, there is a wide range of novel angiogenesis inhibitors which must be tested in combinations with oral chemotherapy agents to assess the anti-endothelial and anti-cancer effects. This preliminary testing is most suited to high throughput in vitro models, rather than clinical trials. We aimed to establish an in vitro model and test the anti-endothelial and anti-cancer effects of the multi-kinase inhibitor sorafenib when used as a single agent and in combination with oral chemotherapy agents used at low concentrations. Micro-vascular endothelial cells and 3 cancer cell lines were utilised and an extended treatment strategy (96 h) was employed in order to mimic a continuous low dose anti-angiogenic chemotherapy regimen. Sorafenib significantly enhanced the anti-endothelial effect of low dose etoposide, paclitaxel and temozolomide. Sorafenib also significantly enhanced the anti-cancer effect of low dose etoposide, paclitaxel and temozolomide in SK-MEL-2 melanoma cells, producing an additive effect on inhibition of cell growth in all cases. These combinations appear to be the most promising for in vivo pre-clinical studies, with a view to testing in melanoma patients as a continuous dosing strategy, due to the in vitro additive inhibitory effect on growth seen in both endothelial and cancer cells.


Subject(s)
Angiogenesis Inhibitors/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Benzenesulfonates/administration & dosage , Endothelial Cells/drug effects , Neovascularization, Pathologic/drug therapy , Pyridines/administration & dosage , Cell Line, Tumor , Cell Proliferation/drug effects , Dacarbazine/administration & dosage , Dacarbazine/analogs & derivatives , Drug Administration Schedule , Etoposide/administration & dosage , Humans , In Vitro Techniques , Niacinamide/analogs & derivatives , Paclitaxel/administration & dosage , Phenylurea Compounds , Sorafenib , Temozolomide
8.
Proteomics ; 8(2): 234-6, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18203275

ABSTRACT

Fifty postgraduate and postdoctoral delegates from all over Europe attended the week-long '1st European Summer School on Proteomic Basics' in Kloster Neustift in the Italian South Tyrol in August 2007. Invited proteomics experts gave tutorial lectures on Proteomics techniques with an emphasis on sample preparation, protein separation and purification in the first of an annual series of Proteomics Summer Schools funded by the EU and the Volkswagen Stiftung.


Subject(s)
Proteomics/education , Animals , Chromatography, Liquid , Humans , Mass Spectrometry , Proteins/isolation & purification , Proteomics/methods , Students
9.
Acta Oncol ; 46(8): 1169-77, 2007.
Article in English | MEDLINE | ID: mdl-17851838

ABSTRACT

UNLABELLED: The effects of 'metronomic' or extended chemotherapy dosing schedules (ECS) are mediated through poorly understood anti-angiogenic mechanisms. ECS combined with biological anti-angiogenic agents have produced promising pre-clinical results. MATERIALS AND METHODS: We have expanded the list of agents with an in vitro ECS profile to include the methylating agent temozolomide (Temodal) and the anti-mitotic agent estramustine (Estracyt). These agents were also combined with a specific anti-angiogenic inhibitor IMC-1C11 and a non-specific agent with anti-angiogenic properties, Compound 5h. The in vitro HUVEC ECS model system was optimised and cell proliferation assays undertaken. RESULTS: As a single agent, estramustine inhibited endothelial cell proliferation with an IC50 of 4.5 microM and was active at 10-33% of the maximum tolerated dose (MTD) from clinical schedules, whilst temozolomide had IC50 of 6.6 microM and was active at 1-6% of MTD. In combination, significant synergy was seen with IMC-1C11 in combination with either drug, whilst modest additive effects were observed with Compound 5h. None of the combinations resulted in significant cytotoxicity or apoptosis. DISCUSSION: The results show that ECS of temozolomide and estramustine can be significantly enhanced when combined with specific anti-angiogenic inhibitors in an in vitro HUVEC system.


Subject(s)
Antibodies/administration & dosage , Dacarbazine/analogs & derivatives , Drug Administration Schedule , Endothelial Cells/drug effects , Estramustine/administration & dosage , Umbilical Veins/drug effects , Vascular Endothelial Growth Factor Receptor-2/immunology , Antibodies, Monoclonal/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Cell Proliferation/drug effects , Cells, Cultured , Dacarbazine/administration & dosage , Dose-Response Relationship, Drug , Drug Synergism , Endothelial Cells/physiology , Humans , Paclitaxel/administration & dosage , Temozolomide , Time Factors , Umbilical Veins/growth & development
10.
Analyst ; 128(10): 1218-21, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14667155

ABSTRACT

The FT-Raman spectra of five epilithic lichen taxa growing on dolomite and magnesium-rich carbonate rocks have been analysed and interpreted for the key molecular marker bands associated with calcium oxalate monohydrate (whewellite), calcium oxalate dihydrate (weddelite) and magnesium oxalate dihydrate. From the results, it can be concluded that the biomineral product of lichen biodeterioration involves the calcareous part of the substratum only; no trace of magnesium oxalate has been found in the Raman spectra. Two of the species, Lecanora sulfurea and Aspicilia calcarea, produce calcium oxalate monohydrate exclusively, but Dirina massiliensis f. sorediata, D. massiliensis f. massiliensis and Tephromela atra produce significant quantities of the dihydrate. An explanation is advanced for the exclusive accumulation of calcium oxalate into the lichen thallus despite the significant presence of magnesium ions.


Subject(s)
Lichens/chemistry , Oxalates/analysis , Calcium Oxalate/analysis , Geologic Sediments , Lichens/metabolism , Spectrum Analysis, Raman/methods
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