Gold Nanorods as Drug Delivery Vehicles for Rifampicin Greatly Improve the Efficacy of Combating Mycobacterium tuberculosis with Good Biocompatibility with the Host Cells.

TB remains a challenging disease to control worldwide. Nanoparticles have been used as drug carriers to deliver high concentrations of antibiotics directly to the site of infection, reducing the duration of treatment along with any side effects of off-target toxicities after systemic exposure to the antibiotics. Herein we have developed a drug delivery platform where gold nanorods (AuNRs) are conjugated to rifampicin (RF), which is released after uptake into macrophage cells (RAW264.7). Due to the nature of the macrophage cells, the nanoparticles are actively internalized into macrophages and release RF after uptake, under the safety frame of the host cells (macrophage). AuNRs without RF conjugation exhibit obvious antimicrobial activity. Therefore, AuNRs could be a promising antimycobacterial agent and an effective delivery vehicle for the antituberculosis drug Rifampicin for use in tuberculosis therapy.

Phenotypic and molecular typing of tuberculous and nontuberculous Mycobacterium species from slaughtered pigs in Egypt.

A total of 745 slaughtered pigs were examined during routine meat inspection for suspected tuberculous lesions. Specimens from suspected lesions were collected for conventional mycobacteriologic examinations. Suspected mycobacterial colonies were subjected to molecular typing based on the Mycobacterium species-specific intergenic spacer (IGS) target. The study resulted in detection of suspected lesions in 110 (14.8%) carcasses, from which only 67 specimens produced suspected mycobacterial colonies. Conventional examination was only able to identify 56 isolates as Mycobacterium species, which was confirmed by polymerase chain reaction amplification of the IGS target. Interestingly, out of these, 18 and 12 isolates were Mycobacterium tuberculosis and Mycobacterium bovis, respectively. Sequence analysis of IGS resolved the identities of 10 of the 11 conventionally unidentified isolates as being 4 different nontuberculous Mycobacterium species. The last isolate was proposed as a non-Mycobacterium species and was confirmed by its identification as Rhodococcus equi based on the 16S ribosomal DNA sequence analysis. The study described the isolation of Mycobacterium tuberculosis from pigs and revealed high burden of infection with both tuberculous and nontuberculous mycobacterial species among pigs in Egypt. In addition, the study showed the usefulness of IGS sequence analysis as a reliable molecular tool that would be useful for further epidemiologic and public health studies.

Genomic Polymorphism Associated with the Emergence of Virulent Isolates of Mycobacterium bovis in the Nile Delta.

Mycobacterium bovis is responsible for bovine tuberculosis in both animals and humans. Despite being one of the most important global zoonotic disease, data related to the ecology and pathogenicity of bovine tuberculosis is scarce, especially in developing countries. In this report, we examined the dynamics of M. bovis transmission among dairy cattle in the Nile Delta of Egypt. Animals belonging to 27 herds from 7 governorates were tested by the Single Intradermal Comparative Skin Tuberculin (SICST), as a preliminary screen for the presence of bovine tuberculosis. Positive SICST reactors were identified in 3% of the animals spread among 40% of the examined herds. Post-mortem examination of slaughtered reactors confirmed the presence of both pulmonary and/or digestive forms of tuberculosis in > 50% of the examined animals. Targeted and whole-genome analysis of M. bovis isolates indicated the emergences of a predominant spoligotype (SB0268) between 2013-2015, suggesting a recent clonal spread of this isolate within the Nile Delta. Surprisingly, 2 isolates belonged to M. bovis BCG group, which are not allowed for animal vaccination in Egypt, while the rest of isolates belonged to the virulent M. bovis clonal complex European 2 present in Latin America and several European countries. Analysis of strain virulence in the murine model of tuberculosis indicated the emergence of a more virulent strain (MBE4) with a specific genotype. More analysis is needed to understand the molecular basis for successful spread of virulent isolates of bovine tuberculosis among animals and to establish genotype/phenotype association.

Ibuprofen suppresses depressive like behavior induced by BCG inoculation in mice: role of nitric oxide and prostaglandin.

Prostaglandins (PGs) and nitric oxide (NO) may be involved in the pathophysiology of depression. Since NSAIDs decrease PGs and NO production, they may have an antidepressant effect. The aim of the present work was to explore a possible antidepressant action of ibuprofen in the new model of Bacillus Calmette-Guerin (BCG) induced depression. Mice injected with BCG (10(7) CFU/mouse intraperitoneally) showed an increase in the total immobility time during the forced swim test (FST) and the tail suspension test (TST) and an increase in cerebral PGE2 and NO levels. Fluoxetine administered in drinking water at a dose of 80 mg/l, 5 days before BCG and for 2 more weeks resulted in significant decrease in total immobility time during FST and TST and in cerebral PGE2 and NO levels. Both ibuprofen (200 mg/l) and L-NAME (1 g/l) administered in drinking water 24 h before BCG and for 2 more weeks resulted in decrease in the total immobility time during FST and TST and in cerebral PGE2 and NO levels, which was comparable to fluoxetine's effect. On the other hand, l-arginine administered at a dose of 6 g/l in drinking water together with ibuprofen or fluoxetine reversed their effect on FST, TST and cerebral PGE2 and NO levels. Immunohistochemistry showed a decrease in COX-1 and i-NOS immunoreactivity in the CA1 and CA3 areas of the hippocampus following ibuprofen treatment. These results suggest that ibuprofen may have an antidepressant effect through inhibition of PGE2 and NO production, especially in depression secondary to chronic inflammation.