Duchenne muscular dystrophy (DMD), caused by mutations in the dystrophin gene, is characterized by progressive muscle weakness. Even though DMD manifests first in skeletal muscle, heart failure is a major cause of death in late-stage DMD. To get insights into DMD-associated cardiomyopathy, we performed a proteome analysis of myocardium from a genetically engineered porcine DMD model resembling clinical and pathological hallmarks of human DMD. To capture DMD progression, samples from 2-day-and 3-month-old animals were analyzed. Dystrophin was absent in all DMD samples, and components of the dystrophinassociated protein complex were decreased, suggesting destabilization of the cardiomyocyte plasma membrane and impaired cellular signaling. Furthermore, abundance alterations of proteins known to be associated with human cardiomyopathy were observed. Compared with data from skeletal muscle, we found clear evidence that DMD progression in myocardium is not only slower than in skeletal muscle but also involves different biological and biochemical pathways.

Antibacterial potential of metallic silver nanoparticles (AgNPs) is considered to be influenced by their size and stability. In this study, the stable AgNPs capped with poly (4-styrenesulfonic acid-co-maleic acid) or PSSMA were successfully synthesized by using a chemical reduction method. The PSSMA-stabilized AgNPs (PSSMA-AgNPs) were characterized and tested for antibacterial activity against eight bacterial strains. Transmission electron microscopic studies showed that PSSMA-AgNPs were monodisperse spherical particles with an average size of 5.21 nm. From bacterial growth curve studies, PSSMA-AgNPs exhibited an antibacterial effect on Gram-positive bacteria (Staphylococcus aureus ATCC 25923, Staphylococcus aureus ATCC 6538p, Staphylococcus aureus ATCC 43300, Staphylococcus epidermidis ATCC 12228 and Bacillus subtilis ATCC 6633) and Gram-negative bacteria (Escherichia coli ATCC 25922, Enterobacter aerogenes ATCC 13048 and Pseudomonas aeruginosa ATCC 27853). Moreover, the Gram-negative bacteria were found to be more susceptible to the AgNPs.

Background While silver nanoparticles (AgNPs) are increasingly attractive as an antibacterial agent in many applications, the effect of AgNPs on bacterial protein profiles, especially AgNPs stabilized by polymeric molecules, is not well understood. Objectives To investigate the changes in bacterial protein patterns by AgNPs capped with poly (4-styrenesulfonic acid-co-maleic acid) (AgNPs-PSSMA) polymer toward Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922. Methods The growth of bacteria after incubated with AgNPs-PSSMA for different time intervals was determined by optical density at 600 nm. Their protein patterns were observed using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and the proteomic analysis of extracted proteins was determined by liquid chromatography-tandem mass spectrometry (LC–MS/MS). Results AgNPs-PSSMA was able to inhibit the growth of both S. aureus and E. coli cells. The treated bacterial cells expressed more proteins than the untreated cells as seen from SDS-PAGE study. Nanosilver (NS) caused the upregulation of metabolic gene, waaA, in S. aureus cells. For E. coli cells, the upregulated proteins were metabolic genes (srlB, fliE, murD) and other genes dealt with DNA replication (dinG), DNA–RNA transcription (yrdD), RNA– protein translation (rplD), molecular transport (sapF), and signal transduction (tdcF). Conclusions The antibacterial effect of AgNPs-PSSMA may arise by changing the bacterial proteins and thus interfering with the normal cell function.

Silver nanoparticles (AgNPs) are of considerable interest for medical application due to their antimicrobial activity. However, only a limited number of natural polymers have been reported as colloidal stabilizers for AgNPs. This study aimed to synthesize AgNPs using hydrocolloids, alginate and carrageenan, as stabilizers. Hydrocolloid-capped AgNPs were synthesized by two methods: M1, a reductive sodium borohydride (NaBH4) method, and M2, a microwave assisted reduction method. The synthesized AgNPs were characterized for surface plasmon resonance (SPR), size, surface charge and morphology. From the results, AgNPs stabilized by alginate (al-AgNPs) and carrageenan (ca-AgNPs) were able to be synthesized by methods M1 and M2. The SPR absorption peak around 400 nm of AgNPs represented the formation of rather spherical particles. The AgNPs formed by method M1were narrower in size distribution than that of AgNPs formed by method M2. Laser doppler electrophoresis (LDE) showed negative surface charges of al-AgNPs and ca-AgNPs because the anionic hydrocolloid polymers consist of carboxylic acid (alginate) and sulfate (carrageenan). Conclusively, AgNPs can be successfully formed and stabilized by alginate and carrageenan. Hydrocolloid-capped AgNPs are stable due to the electrostatic repulsion and steric stabilization of such polymers.