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Background: Alzheimer’s disease (AD) is a neurodegenerative disorder involving memory. The present study aimed at evaluating the effects of encapsulated diphtheria toxoid (DT) on behavioral learning impairment, and XBP1 mRNA splicing in AD. Methods: A DT-loaded nanoparticle (NP) carrier was prepared using the ionic gelation method. Sixty-three rats were divided into nine groups: (1) healthy, (2–4) sham, and (5–9) AD models: (5) AD was induced by intracerebroventricular injection of amyloid beta (Aß) 1-42. (6) The rats received a subcutaneous diphtheria vaccine only 28 days before Aß injection. (7) The rats received an intranasal diphtheria vaccine, in group 8, induced by administering empty chitosan NPs. 9) it was induced by administering chitosan NPs carrying DT. Morris water maze (MWM) test was used to examine the animals’ learning and memory. Also, X-box binding protein 1 (XBP-1) mRNA gene splicing was studied in the hippocampus by reverse-transcription polymerase chain reaction (RT-PCR). Results: For the first time, chitosan NPs were prepared with an average diameter size of 40 nm and the effectiveness of approximately 70% during DT encapsulation. In comparison with the healthy group, the AD models exhibited significant impairment of learning and memory (P?<?0.05), while DT-administrated animals showed significant improvements in learning and memory impairment (P?<?0.05). XBP-1 mRNA gene splicing was only detected in an untreated AD group, while encapsulated DT completely inhibited splicing. Conclusion: The therapeutic effects of DT chitosan NPs against learning and memory impairment were observed in this study, and XBP1 mRNA splicing was reported in the animal models.

Mupirocin is a topical antibiotic for methicillin-resistant Staphylococcus aureus(MRSA) decolonization in hospital settings and nursing homes and is used as a highly effective antibiotic against MRSA. In this study, we aimed to evaluate the frequency of high-level mupirocin-resistant (HLMR) strains among the MRSA subtypes. A total of 188 clinical MRSA isolates were collected from 2011 to 2014, and their susceptibility to antimicrobial agents and vancomycin resistance was evaluated using disc diffusion method and micro-dilution method, respectively. Furthermore, the presence of mecA, SSCmec, mupA and mupB was assessed by PCR. All isolates were multi-drug resistant (MDR) but 2 strains (1.06%) were resistant to mupirocin. Minimum inhibitory concentration (MIC) of vancomycin for 8 strains (4.7%) was higher than 2 μg/ml. Of 188 isolates, 188 (100%), 64 (34.04%), 8 (4.3%), 150 (79.8%), 26 (13.8%), 2 (1.06) and 2 (1.06%) isolates possessed mecA, SCCmec types I, II, III, IV, mupA and mupB genes, respectively. Our data showed that despite infection control policy enforced by health care committee, the rate of mupirocin resistance among MRSA strains is continuously rising.