The Complex Mechanism of the Salmonella typhi Biofilm Formation That Facilitates Pathogenicity: A Review

Salmonella enterica serovar Typhi (S. typhi) is an intracellular pathogen belonging to the Enterobacteriaceae family, where biofilm (aggregation and colonization of cells) formation is one of their advantageous traits. Salmonella typhi is the causative agent of typhoid fever in the human body and is exceptionally host specific. It is transmitted through the fecal-oral route by consuming contaminated food or water. This subspecies is quite intelligent to evade the innate detection and immune response of the host body, leading to systemic dissemination. Consequently, during the period of illness, the gallbladder becomes a harbor and may develop antibiotic resistance. Afterwards, they start contributing to the continuous damage of epithelium cells and make the host asymptomatic and potential carriers of this pathogen for an extended period. Statistically, almost 5% of infected people with Salmonella typhi become chronic carriers and are ready to contribute to future transmission by biofilm formation. Biofilm development is already recognized to link with pathogenicity and plays a crucial role in persistency within the human body. This review seeks to discuss some of the crucial factors related to biofilm development and its mechanism of interaction causing pathogenicity. Understanding the connections between these things will open up a new avenue for finding therapeutic approaches to combat pathogenicity.

The Impact of Micronutrients-Calcium, Vitamin D, Selenium, Zinc in Cardiovascular Health: A Mini Review.

The role of micronutrients in health and disease has increased the curiosity and interest among researchers. The prime focus of this review is the significance of trace elements- calcium, vitamin D, selenium and zinc with cardiovascular health. WHO identified cardiovascular diseases (CVD) as the leading cause of deaths globally. Identifying the risk factors that could be modified and creating new treatment strategies remains to be the main concern for CVD prevention. The data that showed the relationship between trace elements and various ways in which they may contribute to cardiovascular health and disease from clinical trials and observational studies were collected from databases such as PubMed and Embase. Based on these collected data, it shows that either high or low circulating serum levels can be associated with the development of cardiovascular diseases. Micronutrients through diet contribute to improved cardiac health. However, due to our current lifestyle, there is a huge dependency on dietary supplements. Based on the observational studies, it is evident that supplements cause sudden increase in the circulating levels of the nutrients and result in cardiovascular damage. Thus, it is advisable to restrict the use of supplements, owing to the potent risks it may cause. In order to understand the exact mechanism between micronutrients and cardiac health, more clinical studies are required.

Green Synthesis and Characterization of Silver Nanoparticles Using Spondias mombin Extract and Their Antimicrobial Activity against Biofilm-Producing Bacteria.

Multidrug resistant bacteria create a challenging situation for society to treat infections. Multidrug resistance (MDR) is the reason for biofilm bacteria to cause chronic infection. Plant-based nanoparticles could be an alternative solution as potential drug candidates against these MDR bacteria, as many plants are well known for their antimicrobial activity against pathogenic microorganisms. Spondias mombin is a traditional plant which has already been used for medicinal purposes as every part of this plant has been proven to have its own medicinal values. In this research, the S. mombin extract was used to synthesise AgNPs. The synthesized AgNPs were characterized and further tested for their antibacterial, reactive oxygen species and cytotoxicity properties. The characterization results showed the synthesized AgNPs to be between 8 to 50 nm with -11.52 of zeta potential value. The existence of the silver element in the AgNPs was confirmed with the peaks obtained in the EDX spectrometry. Significant antibacterial activity was observed against selected biofilm-forming pathogenic bacteria. The cytotoxicity study with A. salina revealed the LC50 of synthesized AgNPs was at 0.81 mg/mL. Based on the ROS quantification, it was suggested that the ROS production, due to the interaction of AgNP with different bacterial cells, causes structural changes of the cell. This proves that the synthesized AgNPs could be an effective drug against multidrug resistant bacteria.