No abstract

The present study aimed to prepare and characterize anti EGFR monoclonal antibody (mab) conjugated Gemcitabine loaded PLGA nanoparticles for their selective delivery to pancreatic cells and evaluation of the systems in vitro. It was observed that direct covalent coupling of antibodies to glutaraldehyde activated nanoparticles is an appropriate method to achieve cell-type specific drug carrier systems based on polymeric nanoparticles that have potential to be applied for targeted chemotherapy in EGFR positive cancer.

The aim of the present study was the direct covalent coupling of the epidermal growth factor receptor (EGFR)-specific monoclonal antibody (mAb) to the surface of poly(lactide)-co-glycolide (PLGA)-polyethylene glycol (PEG) nanoparticles in order to achieve a cell type-specific drug carrier system against pancreatic cancer. The PLGA-PEG-NH2 diblock copolymer was synthesized by coupling reaction via amide linkage between PEG-diamine and activated PLGA. PLGA and PLGA-PEG-NH2 nanoparticles loaded with gemcitabine were prepared using the double-emulsion solvent evaporation method. PLGA-PEG immunonanoparticles were prepared by glutaraldehyde mediated cross-linking method. The conjugated antibody was analysed by transmission electron microscopy and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (PAGE) analysis. Cell viability study was performed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and cell uptake study was performed on fluorescein isothiocyanate-loaded formulations using confocal microscopy. The PAGE results indicated that mAb integrity was remained intact in the formulations after conjugation. Biological activity was confirmed under cell culture conditions: antibody-conjugated nanoparticles showed specific targeting to EGFR-overexpressing MIA PaCa-2 cell lines as shown in fluorescence image using confocal microscopy. The obtained data provide the basis for the development of stable and biologically active carrier systems for direct targeting of tumour cells using antibody-conjugated PLGA-PEG nanoparticles. Direct covalent coupling of antibodies to nanoparticles using glutaraldehyde as a cross-linker is an appropriate method to achieve cell type-specific drug carrier systems based on PLGA-PEG nanoparticles and the anti-EGFR-decorated PLGA-PEG nanoparticles have potentials to be applied for targeted chemotherapy against EGFR positive cancers.

Our data suggests that trained first-year medical students can effectively teach a point of care ultrasound course to healthcare professional students within four weeks in Tanzania. Future investigation into the level of long-term knowledge retention, impact of ultrasound training on knowledge of human anatomy and diagnostic capabilities, and how expansion of an ultrasound curriculum has impacted access to care in rural Tanzania is warranted.

The screen-and-treat model for the identification and treatment of precancerous cervical lesions is an effective public health intervention with the potential to impact women by providing the tools and education needed by local healthcare professionals. However, limitations common to resource-poor settings, such as continuity of funding, loss to follow-up and transportation costs, remain barriers to sustainability.