Development of Absorption and Fluorescence Probes Based on Mouse Model for Molecular Optical Imaging [abstract]

Comparative Medicine - OneHealth and Comparative Medicine Poster SessionIn this work we summarize our collaborative research on a project to develop absorption and fluorescence targeting probes. Several groups from University of Missouri and Harry S. Truman Memorial Veteran's Hospital including Dr. Ma's group, Dr. Yu's group, Dr. Smith's group, Dr. Hoffman's group, and Professor Wynn Volkert have been involved in the project. Our goal is to develop probes based on mouse model for molecular optical imaging. In vivo imaging of targeted fluorescence molecular probes, or molecular imaging, is an emerging field in biomedical imaging. During the past forty years, three dimensional biomedical imaging technologies such as CT and MRI have been extensively used in human health and diseases. However, the human body is a complex and interactive biological system. A fundamental scientific barrier in previous biomedical imaging technologies is their limited ability to study physiological processes in vivo at the cellular and molecular levels. Molecular imaging technologies can overcome this barrier. Optical imaging modalities have the highest sensitivity compared to other imaging techniques. So they are good candidates for molecular imaging. We develop probes for two biomedical optical imaging techniques. The first technique is coherence domain imaging. This technique can be used to monitor interactions between targeted peptide conjugates and cancer cells at a tissue level. It requires absorption properties of the probe for effective molecular imaging. The second technique is fluorescence mediated tomographic imaging using an image-intensified CCD camera. This technique uses fluorescence of the probe for molecular imaging. Dye bombesin conjugates are synthesized for site-specific absorption and fluorescence imaging in human prostate and breast cancer cells. Bombesin (BBN), an amphibian analog to the endogenous ligand, binds to the gastrin releasing peptide receptors (GRPr) with high specificity and affinity. BBN conjugates have a specific significance in cancer detection and therapy due to high over-expression levels of GRPrs in human cancer cells. Previously, we have developed an Alexa Fluor 680 BBN peptide conjugate. This probe can not be used as an absorption probe in near-infrared imaging since its absorption peak is in the visible wavelength range. In addition, long wavelength fluorescence is desired because long wavelength photons can penetrate deeper into tissue when using the conjugates as a fluorescent probe. The new absorption and fluorescent probe we developed is based on the last eight-residues of BBN and labeled with Alexa Fluor 750 through an effective linker. The developed probe, AF750-BetaAla-BBN[7-14]NH2, exhibits optimal pharmacokinetic properties for targeting GRPr over-expressing cancer cells in mice. Absorption spectra have been measured and showed absorption peaks at 690nm, 720nm and 735nm. Fluorescent band is located at 755nm. Fluorescent microscopic imaging of the conjugates in human PC-3 prostate cancer and T-47D breast cancer cells indicated specific uptake and internalization in vitro. In vivo optical and MR imaging was performed in SCID mice bearing human breast and prostate xenografts. In vitro and in vivo studies have demonstrated the effectiveness of the fluorescent probe Alexa Fluor 750-BetaAla-BBN[7-14]NH2 to specifically target GRPr overexpressed cancer tissues

The Multi-Soliton Solutions to The KdV Equation by Hirota Method

The Hirota bilinear method is used to solve the KdV model. As a result, the exact expression of multi-soliton solutions of the KdV equation is obtained

The Applications of ISM Model

The students' interest refers to the knowledge of a positive emotional state, is caused by the motivation to learn, an important factor to promote student learning. Students of weariness largely depend of students' interest. There are many factors that a ect students' interest in learning, both objective factors and subjective factors. The reasons that a ect students learning interest are analyzed by using the interpretative structural modeling (ISM)

A human relevent rat model of breast cancer

Abstract only availableBecause women experience a bewildering array of chemicals, foods and lifestyles, only profound effects on preventing or promoting breast cancer are detectible in human studies. Subtle or delayed effects can be detected in animal models. Mammary tumors in ACI rats share important similarities with the majority of human breast cancers. The link between life time estrogen exposure and breast cancer risk in humans is well established. A high percentage of human breast cancers express ER, are stimulated to grow by the addition of exogenous estrogen, and respond to the antiestrogen tamoxifen. The ACI rat is the only rodent model in which estrogen-sensitive tumors are induced by estrogen. The ACI.COP-Ept2 substrain, derived from the ACI rat, develops mammary tumors similar to those of the ACI rat, but with reduced pituitary hyperplasia. We show that estrogen-induced mammary tumors in ACI.COP-Ept2 express ERα and respond to tamoxifen. Furthermore, tumors express ERβ, progesterone receptor and Her2/neu. The average latency was 183±6 days (n=24) and average tumor burden 1,107±415 mm3. The similarities of ACI.COP-Ept2 tumors to human breast cancers make this a valuable model for determining which of the myriad of lifestyle and diet choices reportedly protecting women from breast cancer actually reduce cancer incidence.Food for the 21st Century Undergraduate Research Program in Nutritional Science

Embeddings Among Toruses and Meshes

Toruses and meshes include graphs of many varieties of topologies, with lines, rings, and hypercubes being special cases. Given a d-dimensional torus or mesh G and a c-dimensional torus or mesh H of the same size, we study the problem of embedding G in H to minimize the dilation cost. For increasing dimension cases (d \u3c c) in which the shapes of G and H satisfy the condition of expansion, the dilation costs of our embeddings are either 1 or 2, depending on the types of graphs of G and H. These embeddings a,re optimal except when G is a torus of even size and H is a mesh. For lowering dimension cases (d \u3e c) in which the shapes of G and H satisfy the condition of reduction, the dilation costs of our embeddings depend on the shapes of G and H. These embeddings, however, are not optimal in general. For the special cases in which G and H are square, the embedding results above can always be used to construct embeddings of G in H: these embeddings are all optimal for increasing dimension cases in which the dimension of H is divisible by the dimension of G, and all optimal to within a constant for fixed values of d and c for lowering dimension cases. Our main analysis technique is based on a generalization of Gray code for radix-2 (binary) numbering system to similar sequences for mixed-radix numbering systems

Variational Iteration Method for Solving the Generalized Degasperis-Procesi Equation

We introduce the variational iteration method for solving the generalized Degasperis-Procesi equation. Firstly, according to the variational iteration, the Lagrange multiplier is found after making the correction functional. Furthermore, several approximations of un+1(x,t) which is converged to u(x,t) are obtained, and the exact solutions of Degasperis-Procesi equation will be obtained by using the traditional variational iteration method with a suitable initial approximation u0(x,t). Finally, after giving the perturbation item, the approximate solution for original equation will be expressed specifically

Revisiting Cardassian Model and Cosmic Constraint

In this paper, we revisit the Cardassian model in which the radiation energy component is included. It is important for early epoch when the radiation cannot be neglected because the equation of state (EoS) of the effective dark energy becomes time variable. Therefore, it is not equivalent to the quintessence model with a constant EoS anymore. This situation was almost overlooked in the literature. By using the recent released Union2 557 of type Ia supernovae (SN Ia), the baryon acoustic oscillation (BAO) from Sloan Digital Sky Survey and the WiggleZ data points, the full information of cosmic microwave background (CMB) measurement given by the seven-year Wilkinson Microwave Anisotropy Probe observation, we constrain the Cardassian model via the Markov Chain Monte Carlo (MCMC) method. A tight constraint is obtained: $n= -0.0479_{- 0.0732- 0.148}^{+ 0.0730+ 0.142}$ in $1,2\sigma$ regions. The deviation of Cardassian model from quintessence model is shown in CMB anisotropic power spectra at high l's parts due to the evolution of EoS. But it is about the order of 0.1% which cannot be discriminated by current data sets. The Cardassian model is consistent with current cosmic observational data sets.Comment: 6 pages, 5 figures, match the published versio

Visualization study on the instabilities of phase-change heat transfer in a flat two-phase closed thermosyphon

This paper presents systematic experiments and visualization on the instabilities of phase-change heat transfer for water, ethanol and acetone in a flat evaporator of a two phase closed system, respectively. The effects of the heat flux, filling ratio, coolant temperature and working fluid type on the instabilities and their mechanisms have been systematically investigated. The experimental results show that the instabilities of phase-change heat transfer are strongly related to the corresponding heat transfer modes. The instabilities of temperature and heat transfer coefficient (HTC) of the evaporator are mainly caused by the bubble behaviours, the physical properties and the operation pressures. Natural convection, intermittent boiling and fully developed nucleate boiling are the main heat transfer modes in the present study. The condensate droplets may affect the instabilities due to inducing periodic boiling at lower heat fluxes. The maximum standard deviations of the evaporator temperature and vapor pressure fluctuations can reach 3.1 °C and 0.8 kPa respectively during the intermittent boiling. There is no intermittent boiling regime for ethanol and acetone in the present study. Therefore, no instability phenomena of nucleate boiling with ethanol and acetone are observed in the present study