Publications by authors named "Colin K Hill"

A hybrid of radiotherapy and photodynamic therapy (PDT) has been proposed in previously reported studies. This approach utilizes scintillating nanoparticles to transfer energy to attached photosensitizers, thus generating singlet oxygen for local killing of malignant cells. Its effectiveness strongly depends upon the scintillation yield of the nanoparticles.

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CexLa1-xF3 nanoparticles have been proposed for use in nanoscintillator-photosensitizer systems, where excitation of nanoparticles by ionizing radiation would result in energy transfer to photosensitizer molecules, effectively combining the effects of radiotherapy and photodynamic therapy. Thus far, there have been few experimental investigations of such systems. This study reports novel synthesis methods for water-dispersible Ce0.

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The renin-angiotensin system (RAS) plays an important role in wound repair; however, little is known pertaining to RAS expression in response to thermal injury and the combination of radiation plus burn injury (CRBI). The purpose of this study was to test the hypothesis that thermal injury modifies expression of RAS components and CRBI delayed this up-regulation of RAS. Skin from uninjured mice was compared with mice receiving local thermal injury or CRBI (injury site).

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The ability of the liver to regenerate is crucial to protect liver function after injury and during chronic disease. Increases in hepatocyte growth factor (HGF) in liver sinusoidal endothelial cells (LSECs) are thought to drive liver regeneration. However, in contrast to endothelial progenitor cells, mature LSECs express little HGF.

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Background & Aims: Damage to hepatic sinusoidal endothelial cells (SECs) initiates sinusoidal obstruction syndrome (SOS), which is most commonly a consequence of myeloablative chemoirradiation or ingestion of pyrrolizidine alkaloids such as monocrotaline (Mct). This study examines whether SECs are of bone marrow origin, whether bone marrow repair can be a determinant of severity of liver injury, and whether treatment with progenitor cells is beneficial.

Methods: Mct-treated female rats received infusion of male whole bone marrow or CD133(+) cells at the peak of sinusoidal injury.

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Although moderate to high-dose ionizing radiation exposure is an established risk factor for breast cancer, the effect of low-dose radiation exposure has not been clarified by epidemiological data. We evaluated the effect of low-dose radiation from medical procedures on risk of breast cancer overall and by joint estrogen and progesterone receptor (ER/PR) status in 1,742 population-based case patients aged 20-49 years and 441 control subjects identified from neighbourhoods of case patients in Los Angeles County. After excluding radiation exposures in the 5 years prior to case's diagnosis or control's initial household contact date we found an elevated breast cancer risk among women who reported having had multiple chest X-rays (Ptrend=0.

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Upregulation of the cAMP/protein kinase A (PKA) pathway has been shown to result in decreased proliferation, increased differentiation, and subsequent apoptosis of malignant glioma cells. Conventional cAMP analogs, however, are difficult to use in a clinical setting. Therefore, we investigated the effects of rolipram, a drug that has undergone clinical trials as an antidepressant and has also been proposed as a treatment for multiple sclerosis.

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