Publications by authors named "Rebecca K Lee"

To determine whether direct observational scores were predictive of the potency of pharmacy students' compounded sterile preparations (CSPs) and to identify any misunderstandings students had regarding individual aseptic technique steps. P1 students performed aseptic techniques during three observational encounters separated by two weeks. Students' performances were evaluated using an observation-based rubric and were subject to potency analysis.

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HIV-1 infection is enhanced by adhesive structures that form between infected and uninfected T cells called virological synapses (VSs). This mode of transmission results in the frequent co-transmission of multiple copies of HIV-1 across the VS, which can reduce sensitivity to antiretroviral drugs. Studying HIV-1 infection of humanized mice, we measured the frequency of co-transmission and the spatiotemporal organization of infected cells as indicators of cell-to-cell transmission in vivo.

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Although the etiology of squamous cell carcinomas of the oral mucosa is well understood, the cellular origin and the exact molecular mechanisms leading to their formation are not. Previously, we observed the coordinated loss of E-cadherin (CDH1) and transforming growth factor beta receptor II (TGFBR2) in esophageal squamous tumors. To investigate if the coordinated loss of Cdh1 and Tgfbr2 is sufficient to induce tumorigenesis in vivo, we developed two mouse models targeting ablation of both genes constitutively or inducibly in the oral-esophageal epithelium.

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We present a study on the surface-enhanced Raman scattering (SERS) properties of Ag nanoparticle island substrates (NIS) and their applications for target oligonucleotide (OND) detection. It has been found that the surface nanostructure of NIS samples can be controlled with a good degree of reproducibility, and a high SERS enhancement can be achieved when the peak extinction wavelength of NIS is tuned to a spectral window (approximately 60 nm) between the excitation wavelength and the scattered Raman wavelength. The highest SERS enhancement was obtained from the NIS substrates with a nominal thickness of 50 A.

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We report the transfection of human hepatocarcinoma (HepG2) cells by femtosecond (fs) laser pulses at 1554 nm. It was found that HepG2 cells could be perforated transiently to admit propidium iodide by that laser. This photoporation was safe, as the membrane resealed itself within a short time and no mitochondrial depolarization was detected.

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We previously showed that polyphyllin D (PD) produced a stronger apoptotic effect in R-HepG2 with multi-drug resistance (MDR) than that in its parent HepG2 cells without MDR. In this study, PD was found to elicit mitochondrial fragmentation in live cells by using total internal reflection fluorescence microscopy (TIRFM). When mitochondria were isolated and treated directly with PD, a stronger swelling, deeper transmembrane depolarization, and more apoptosis-inducing factor (AIF) release were observed from the mitochondria of R-HepG2 than that of HepG2.

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Nuclear tubules (NTs) were found in the nucleus of HeLa cells. Although no function has been ascribed to these structures, our previous data has shown that they are the sites of Ca(2+) release with mitochondria shuttled around. In the present study, we further characterized these NTs through different fluorescent dye-labeling and red fluorescent protein transfection experiments.

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