Publications by authors named "G V P Chandramouli"

Purpose: In this study, we compared two triarylmethyl (TAM) spin probes, Ox071 and Ox063 for their efficacy in measuring tissue oxygen levels under hypoxic and normoxic conditions by R *-based EPR oximetry.

Methods: The R * dependencies on the spin probe concentration and oxygen level were calibrated using deoxygenated 1, 2, 5, and 10 mM standard solutions and 2 mM solutions saturated at 0%, 2%, 5%, 10%, and 21% of oxygen. For the hypoxic model, in vivo imaging of a MIA PaCa-2 tumor implanted in the hind leg of a mouse was performed on successive days by R *-based EPR oximetry using either Ox071 or Ox063.

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Pancreatic ductal adenocarcinomas (PDACs) form hypovascular and hypoxic tumors, which are difficult to treat with current chemotherapy regimens. Gemcitabine (GEM) is often used as a first-line treatment for PDACs but has issues with chemoresistance and penetration in the interior of the tumor. Evofosfamide, a hypoxia-activated prodrug, has been shown to be effective in combination with GEM, although the mechanism of each drug on the other has not been established.

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Purpose: PEGylated human hyaluronidase (PEGPH20) enzymatically depletes hyaluronan, an important component of the extracellular matrix, increasing the delivery of therapeutic molecules. Combinations of chemotherapy and PEGPH20, however, have been unsuccessful in Phase III clinical trials. We hypothesize that by increasing tumor oxygenation by improving vascular patency and perfusion, PEGPH20 will also act as a radiosensitization agent.

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Endometrial cancer (EC) is a common and deadly cancer in women and novel therapeutic approaches are urgently needed. Polyamines (putrescine, spermidine, spermine) are critical for mammalian cell proliferation and MYC coordinately regulates polyamine metabolism through ornithine decarboxylase (ODC). ODC is a MYC target gene and rate-limiting enzyme of polyamine biosynthesis and the FDA-approved anti-protozoan drug α-difluoromethylornithine (DFMO) inhibits ODC activity and induces polyamine depletion that leads to tumour growth arrest.

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The nitroxide, Tempol, prevents obesity related changes in mice fed a high fat diet (HFD). The purpose of this study was to gain insight into the mechanisms that result in such changes by Tempol in female C3H mice. Microarray methodology, Western blotting, bile acid analyses, and gut microbiome sequencing were used to identify multiple genes, proteins, bile acids, and bacteria that are regulated by Tempol in female C3H mice on HFD.

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