Pro-angiogenic and antibacterial copper containing nanoparticles in PLGA/amorphous calcium phosphate bone nanocomposites

Large bone defects after trauma demand for adequate bone substitutes. Bone void fillers should be antibacterial and pro-angiogenic. One viable option is the use of composite materials like the combination of PLGA and amorphous calcium phosphate (aCaP). Copper stimulates angiogenesis and has antibacterial qualities. Either copper oxide (CuO) nanoparticles (NPs) were therefore added to PLGA/aCaP/CuO in different concentrations (1, 5 and 10 w/w %) or copper-doped tricalcium phosphate NPs (TCP with 2% of copper) were electrospun into PLGA/CuTCP nanocomposites. Bi-layered nanocomposites of PLGA/aCaP with different copper NPs (CuO or TCP) and a second layer of pristine PLGA were fabricated. Two clinical bacterial isolates (Staphylococcus aureus and Staphylococcus epidermidis) were used to assess antibacterial properties of the copper-containing materials. For angiogenesis, the chorioallantoic membrane (CAM) assay of the chicken embryo was performed. The higher the CuO content, the higher were the antibacterial properties, with 10 % CuO reducing bacterial adhesion most effectively. Vessel and cell densities were highest in the 5 % CuO containing scaffolds, while tissue integration was more pronounced at lower CuO content. The PLGA/aCaP/CuO (1 % CuO) behaved similar like PLGA/CuTCP in all angiogenic and antibacterial readouts, based on the same copper fraction. We conclude that CuO NPs or CuTCP NPs are useful components to increase angiogenic properties of nanocomposites and at the same time exhibiting antibacterial characteristics

Investigations on the diagnosis and retroviral aetiology of renal neoplasia in budgerigars (Melopsittacus undulatus)

The high susceptibility of budgerigars (Melopsittacus undulatus) to neoplasia, and specifically renal neoplasia, has often been reported. Further investigations led to a suspicion of a retrovirus as the causative agent for renal neoplasia in budgerigars, but definitive proof has yet to be found. In the present study, 32 budgerigars suspected of having renal neoplasia (based on the clinical presentation) were examined. The objectives were to investigate the use of different diagnostic methods for the ante-mortem diagnosis of this condition and to find more supporting evidence of a retroviral aetiology. The predominant clinical signs observed in budgerigars with renal neoplasia were lameness and absence of deep pain sensation of one leg. Alterations in haematology, plasma chemistry, and urine analyses could not pinpoint the cases of renal neoplasia. Contrast radiography of the intestinal tract proved to be diagnostically more useful compared with plain radiographic studies. Histology confirmed the renal neoplasia as adenocarcinoma. Investigations for virus identification included product-enhanced reverse transcriptase assay and enzyme-linked immunosorbent assay for the detection of avian leucosis virus group-specific antigen. Cell cultures and electron microscopy were performed on a limited number of patients. These investigations could find no presence of an exogenous, replicating retrovirus, neither could viral particles be detected by electron microscopy. Based on the current findings, it can be concluded that there is no evidence of retroviral involvement in the occurrence of renal neoplasia in budgerigars

Improved HIV-1 RNA quantitation by COBAS AmpliPrep/COBAS TaqMan HIV-1 Test, v2.0 using a novel dual-target approach.

BACKGROUND: HIV-1 RNA viral load is a key parameter for reliable treatment monitoring of HIV-1 infection. Accurate HIV-1 RNA quantitation can be impaired by primer and probe sequence polymorphisms as a result of tremendous genetic diversity and ongoing evolution of HIV-1. A novel dual HIV-1 target amplification approach was realized in the quantitative COBAS AmpliPrep/COBAS TaqMan HIV-1 Test, v2.0 (HIV-1 TaqMan test v2.0) to cope with the high genetic diversity of the virus. OBJECTIVES AND STUDY DESIGN: The performance of the new assay was evaluated for sensitivity, dynamic range, precision, subtype inclusivity, diagnostic and analytical specificity, interfering substances, and correlation with the COBAS AmpliPrep/COBAS TaqMan HIV-1 (HIV-1 TaqMan test v1.0) predecessor test in patients specimens. RESULTS: The new assay demonstrated a sensitivity of 20 copies/mL, a linear measuring range of 20-10,000,000 copies/mL, with a lower limit of quantitation of 20 copies/mL. HIV-1 Group M subtypes and HIV-1 Group O were quantified within +/-0.3 log(10) of the assigned titers. Specificity was 100% in 660 tested specimens, no cross reactivity was found for 15 pathogens nor any interference for endogenous substances or 29 drugs. Good comparability with the predecessor assay was demonstrated in 82 positive patient samples. In selected clinical samples 35/66 specimens were found underquantitated in the predecessor assay; all were quantitated correctly in the new assay. CONCLUSIONS: The dual-target approach for the HIV-1 TaqMan test v2.0 enables superior HIV-1 Group M subtype coverage including HIV-1 Group O detection. Correct quantitation of specimens underquantitated in the HIV-1 TaqMan test v1.0 test was demonstrated

Pro-angiogenic and antibacterial copper containing nanoparticles in PLGA/amorphous calcium phosphate bone nanocomposites

Large bone defects after trauma demand for adequate bone substitutes. Bone void fillers should be antibacterial and pro-angiogenic. One viable option is the use of composite materials like the combination of PLGA and amorphous calcium phosphate (aCaP). Copper stimulates angiogenesis and has antibacterial qualities. Either copper oxide (CuO) nanoparticles (NPs) were therefore added to PLGA/aCaP/CuO in different concentrations (1, 5 and 10 w/w %) or copper-doped tricalcium phosphate NPs (TCP with 2% of copper) were electrospun into PLGA/CuTCP nanocomposites. Bi-layered nanocomposites of PLGA/aCaP with different copper NPs (CuO or TCP) and a second layer of pristine PLGA were fabricated. Two clinical bacterial isolates (Staphylococcus aureus and Staphylococcus epidermidis) were used to assess antibacterial properties of the copper-containing materials. For angiogenesis, the chorioallantoic membrane (CAM) assay of the chicken embryo was performed. The higher the CuO content, the higher were the antibacterial properties, with 10 % CuO reducing bacterial adhesion most effectively. Vessel and cell densities were highest in the 5 % CuO containing scaffolds, while tissue integration was more pronounced at lower CuO content. The PLGA/aCaP/CuO (1 % CuO) behaved similar like PLGA/CuTCP in all angiogenic and antibacterial readouts, based on the same copper fraction. We conclude that CuO NPs or CuTCP NPs are useful components to increase angiogenic properties of nanocomposites and at the same time exhibiting antibacterial characteristics.ISSN:2405-844