Cellular Flow Cytometric Studies

This review focuses on flow cytometric studies at the single cell level. Currently, flow cytometry is used to analyze DNA content, cell cycle distribution, cellular viability, apoptosis, calcium flux, intracellular pH and expression of cell surface compounds in targeted cell populations. Our criteria for the selection of research papers for this review were focused on those that show current cellular applications of flow cytometry

Assessment of spin-lattice T1 and spin-spin T2 relaxation time measurements in breast cell cultures at 1.5 Tesla as a potential diagnostic tool in vitro

Magnetic resonance imaging (MRI) is a critically important tool in current medicine. This dynamic diagnostic method allows for detailed and accurate imaging of the human body and diagnosis of metabolic changes by magnetic resonance spectroscopy (MRS) assays. Our work presented herein shows measurement of spin-lattice T1 and spin-spin T2 relaxation time as an indicator of changes in cellular morphology. MRI spin-lattice T1 and spin-spin T2 relaxation time measurements are innovative experiments that provide a detailed picture of the biological microenvironment within cell cultures. Here, we used two types of cell cultures: cancerous and healthy breast cells. By measuring spin-lattice T1 and spin-spin T2 relaxation time in cancerous and healthy cell cultures we can detect differences and morphological conditions of both cell lines. A number of observations indicate that MRI can detect differences between cancer and healthy cells. In order to obtain a high density of cells for our cellular MRI study, we grew the cells in 3D geometry. In this paper, we underline the potential of quantitative MRI in vitro for future cellular mapping of drug concentration and drug efficiency in cell culture. We have shown that MRI, which is used often for imaging of anatomy, is also a promising technology for specific morphological measurements of cells

Solid pseudopapillary neoplasm of the pancreas: a case report

This paper presents a case report of a solid pseudopapillary neoplasm (SPN) of the pancreas, a discussion on the clinical-pathological, histopathological, and immunohistochemical picture, and a review of the literature regarding the occurrence of this type of cancer. The case of a 61-year-old woman with the presence of a lithium-cystic lesion of the body and tail of the pancreas was initially assessed by MRI as a pathological mass with the presence of abscesses. Double biopsy under EUS control was non-diagnostic. The patient underwent surgery to remove the body and tail of the pancreas together with the tumour and spleen. Tumour size 15×10×8 cm lithium-cystic, grey-brown, with the presence of numerous calcifications and bone metaplasia, and stones in the pancreatic duct. In the histopathological picture, solid woven with the presence of pseudodimplants and pseudocystic areas with haemorrhages. Positive tests for NSE, vimentin, PR, CD56, and cyclin D1 were obtained in immunohistochemical (IHC) tests. The patient was discharged from the hospital in good general condition and is under gastroenterological control. SPN is a rare cancer with low malignancy. The tumour most often occurs in teenagers or young women. Initially, it runs without ailments, until it is large. Then there is pain, nausea, and fever. The histopathological and cytological picture is suggestive, but it should be supported by research. SPN should be differentiated with neuroendocrine tumours (NENs) and acinar cancer and pancreatoblasoma. SPN generally has a good prognosis. Local relapses and distant metastases are rare

Antioxidant Networks In vivo

Oxygen interacts with cells and can form highly reactive compounds in vivo known as reactive oxygen species (ROS). High levels of ROS can lead to cellular damage, oxidative stress, heart diseases and cancer. Known substances that are capable of halting the physiological process of oxidation in tissue are called antioxidants.This review covers developments in the field of antioxidant chemistry including interactions between antioxidants and ROS, topics about sources and natural occurrences, classification of antioxidants and a discussion of possible mechanisms. We also summarize examples of oxidative stress biomarkers.

Singlet Oxygen Generation on Porous Superhydrophobic Surfaces: Effect of Gas Flow and Sensitizer Wetting on Trapping Efficiency

We describe physical-organic studies of singlet oxygen generation and transport into an aqueous solution supported on superhydrophobic surfaces on which silicon–phthalocyanine (Pc) particles are immobilized. Singlet oxygen (1O2) was trapped by a water-soluble anthracene compound and monitored in situ using a UV–vis spectrometer. When oxygen flows through the porous superhydrophobic surface, singlet oxygen generated in the plastron (i.e., the gas layer beneath the liquid) is transported into the solution within gas bubbles, thereby increasing the liquid–gas surface area over which singlet oxygen can be trapped. Higher photooxidation rates were achieved in flowing oxygen, as compared to when the gas in the plastron was static. Superhydrophobic surfaces were also synthesized so that the Pc particles were located in contact with, or isolated from, the aqueous solution to evaluate the relative effectiveness of singlet oxygen generated in solution and the gas phase, respectively; singlet oxygen generated on particles wetted by the solution was trapped more efficiently than singlet oxygen generated in the plastron, even in the presence of flowing oxygen gas. A mechanism is proposed that explains how Pc particle wetting, plastron gas composition and flow rate as well as gas saturation of the aqueous solution affect singlet oxygen trapping efficiency. These stable superhydrophobic surfaces, which can physically isolate the photosensitizer particles from the solution may be of practical importance for delivering singlet oxygen for water purification and medical devices

Superhydrophobic surfaces as a source of airborne singlet oxygen through free space for photodynamic therapy

A superhydrophobic (SH) sandwich system has been developed to enable "contact-free" airborne singlet oxygen (1O2) delivery to a water droplet. The contact-free feature means that the sensitizer is physically separated from the droplet, which presents opportunities for photodynamic therapy (PDT). Trapping of airborne 1O2 in a H2O droplet residing on a lower SH surface was monitored with 9,10-anthracene dipropionate dianion by varying distances to an upper 1O2-generating surface. Short distances of 20 μm efficiently delivered airborne 1O2 to the droplet in single-digit picomolar steady-state concentrations. Delivery decreases linearly with distance, but 50% of the 1O2 steady-state concentration is trapped at a distance of 300 μm from the generating surface. The 1270 nm luminescence intensity was measured within the SH sandwich system, confirming the presence of airborne 1O2. Physical quenching of 1O2 to ground-state 3O2 by the water droplet itself and both physical and chemical quenching of 1O2 by the water droplet containing the trap 9,10-anthracene dipropionate dianion are observed. Unlike a majority of work in the field of PDT with dissolved sensitizers, where 1O2 diffuses short (hundreds of nanometers) distances, we show the delivery of airborne 1O2 via a superhydrophobic surface is effective through air in tenths of millimeters distances to oxidize an organic compound in water. Our results provide not only potential relevance to PDT but also surface bacterial inactivation processes.Fil: Aebisher, David. University Of Rzeszow; PoloniaFil: Bartusik-Aebisher, Dorota. University Of Rzeszow; PoloniaFil: Belh, Sarah J.. City University of New York; Estados UnidosFil: Ghosh, Goutam. City University of New York; Estados UnidosFil: Durantini, Andres Matías. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; ArgentinaFil: Liu, Yang. City University of New York; Estados UnidosFil: Xu, QianFeng. City University of New York; Estados UnidosFil: Lyons, Alan M.. City University of New York; Estados UnidosFil: Greer, Alexander. City University of New York; Estados Unido

Trastuzumab-dendrimer-fluorine drug delivery system

Breast cancer is the most frequently occurring cancer in women worldwide with more than one million new cases diagnosed each year. The objective of this study was to develop a Trastuzumab-dendrimer-fluorine drug delivery system by covalent attachment of Trastuzumab to a fluorinated PAMAM-G5 dendrimer. The Trastuzumab-dendrimer-fluorine drug delivery system was used to treat MCF-7 with Her-2 overexpression. The use of PAMAM-G5, which bears 128 primary amine surface groups, enables covalent attachment of both antibody and fluorinated functional groups for enhancement of cellular uptake. Thus, Trastuzumab was covalently attached to fluorinated PAMAM-G5 dendrimers and used as a vehicle for drug delivery to three dimensional (3D) cultured cells. The efficiency of Trastuzumab-dendrimer-fluorine drug delivery system binding to Her-2 receptors was measured by cell viability. The Trastuzumab-dendrimer-fluorine drug delivery system was found to have a higher efficiency in the treatment of Her-2 overexpressing MCF-7 cells than Trastuzumab alone. The incorporation of 19F by addition of heptafluorobutyric acid anhydride (HFAA) to PAMAM-G5 increased lipophilicity and hydrophobicity of drug delivery system

Application of 19F magnetic resonance to study the efficacy of fluorine labeled drugs in the three-dimensional cultured breast cancer cells

The cellular monitoring of tumor response to treatments is important for drug discovery and drug development in cancer therapy. We studied efficacy of Herceptin, a common breast cancer drug conjugated with a fluorine organic compound, perfluoro-15-crown-5-ether (PFCE) which easily forms biocompatible emulsions. Three new pharmaceutical forms of Herceptin, Herceptin/PFCE, Herceptin/PFCE/Lipoplex and Herceptin/PFCE/HydraLink were synthesized for the ex vivo study of their efficacy in breast cancer treatment. The emulsions were administered to 109 cells mL-1 of HER-2 positive human adenocarcinoma (MCF-7) cells and the same amount of human mammary epithelial cells (HMEC) cultured in three-dimensional (3D) geometry using hollow fiber bioreactor (HFB) device. Following drugs administration ex vivo, fluorine-19 magnetic resonance imaging (19F MRI) was applied for cells imaging to measure their viability and to study drug efficacy over 72 h. To ensure optimum drug tracking, HydraLink was used to provide stable binding affinity of emulsified Herceptin to receptor while cationic lipid (Lipofectamine) was used to enhance lipophilicity of the emulsions. After 72 h of treatment with Herceptin, Herceptin/PFCE, Herceptin/PFCE/Lipoplex and Herceptin/PFCE/HydraLink the viability of cells was 54 \ub1 2%, 49 \ub1 3%, 43 \ub1 5% and 42 \ub1 1%, respectively, as compared with control 93 \ub1 2%. The efficacy (EC50) of Herceptin conjugated with emulsions was found to be 970 \ub1 13 \u3bcg mL-1 for Herceptin/PFCE, 645 \ub1 11 \u3bcg mL-1 for Herceptin/PFCE/Lipoplex, 678 \ub1 7 \u3bcg mL-1 for Herceptin/PFCE/HydraLink and 1000 \ub1 3 \u3bcg mL-1 for Herceptin. The results show that fluorine emulsions improved the efficacy of Herceptin and 19F signal intensity changes validated drug efficiency. The significant correlations between duration of treatments and MCF-7 cells viability were observed. While we studied breast cancer cells, the fluorine emulsions could be applied for treatment of other cancer cells overexpressing HER-2.Peer reviewed: YesNRC publication: Ye