PIXE analysis for measuring the trace elements concentration in breast tissue of Iranian

ABSTRACT Background: A powerful and improved technique, Proton Induced X-ray Emission (PIXE) has been performed-yielding the elemental composition of 17 samples of surgically excised malignant and normal tumors of breast tissue. The samples without any further process as thick targets were put on capton foil backing. There are no homogenizing processes. The PIXE spectra analysis was performed using he non-linear least square fitting code AXIL and GUPIX. Materials and Methods: The samples are taken from patients in the wide range of age and are bombarded by 2.0 MeV energy proton beams produced by van de graff accelerator in vacuum. The quantitative comparison between two types of tissues was evaluated by assessing the presence of Calcium, Potassium, Iron, Copper and Zinc, as minor and trace elements. Results: Results in this study indicate that relative values of Cu / Zn, P / K and also Ca and S in benign type were higher than those in malignant type, but the concentration of Fe and Zn in cancerous tissues was significantly higher than those for benign type. Conclusion:Results suggest significant elevation of Zinc in the pathological tissues. Cu/Zn ratio for both type of tissues are evaluated. The results show that this ratio in patients with breast cancer is significantly lower than the normal group. Selenium and Arsenic was not obtained in any of 17 samples. Most of the tissues of benign kind (Fibrocystic and Fibro adenoma) contain Cadmium. Calcium concentration in normal tissues is significantly higher than tumorous tissues

Bioanalytical Approaches to Quantify “Total” and “Free” Therapeutic Antibodies and Their Targets: Technical Challenges and PK/PD Applications Over the Course of Drug Development

The predominant driver of bioanalysis in supporting drug development is the intended use of the data. Ligand-binding assays (LBA) are widely used for the analysis of protein biotherapeutics and target ligands (L) to support pharmacokinetics/pharmacodynamics (PK/PD) and safety assessments. For monoclonal antibody drugs (mAb), in particular, which non-covalently bind to L, multiple forms of mAb and L can exist in vivo, including free mAb, free L, and mono- and/or bivalent complexes of mAb and L. Given the complexity of the dynamic binding equilibrium occurring in the body after dosing and multiple sources of perturbation of the equilibrium during bioanalysis, it is clear that ex vivo quantification of the forms of interest (free, bound, or total mAb and L) may differ from the actual ones in vivo. LBA reagents and assay formats can be designed in principle to measure the total or free forms of mAb and L. However, confirmation of the forms being measured under the specified conditions can be technically challenging. The assay forms and issues must be clearly communicated and understood appropriately by all stakeholders as the program proceeds through the development process. This paper focuses on monoclonal antibody biotherapeutics and their circulatory L that are either secreted as soluble forms or shed from membrane receptors. It presents an investigation into the theoretical and practical considerations for total/free analyte assessment to increase awareness in the scientific community and offer bioanalytical approaches to provide appropriate PK/PD information required at specific phases of drug development

Micro reactors: principles and applications in organic synthesis

Graphical Abstrac