Streptococcus Mutans: A Potential Risk Factor in Recurrent Hemorrhagic Stroke

Importance of microbial amphiphiles: interaction potential of biosurfactants, amyloids, and other exo-polymeric-substances

Microorganisms produce a diverse group of biomolecules having amphipathic nature (amphiphiles). Microbial amphiphiles, including amyloids, bio-surfactants, and other exo-polymeric substances, play a crucial role in various biological processes and have gained significant attention recently. Although diverse in biochemical composition, these amphiphiles have been reported for common microbial traits like biofilm formation and pathogenicity due to their ability to act as surface active agents with active interfacial properties essential for microbes to grow in various niches. This enables microbes to reduce surface tension, emulsification, dispersion, and attachment at the interface. In this report, the ecological importance and biotechnological usage of important amphiphiles have been discussed. The low molecular weight amphiphiles like biosurfactants, siderophores, and peptides showing helical and antimicrobial activities have been extensively reported for their ability to work as quorum-sensing mediators. While high molecular weight amphiphiles make up amyloid fibers, exopolysaccharides, liposomes, or magnetosomes have been shown to have a significant influence in deciding microbial physiology and survival. In this report, we have discussed the functional similarities and biochemical variations of several amphipathic biomolecules produced by microbes, and the present report shows these amphiphiles showing polyphyletic and ecophysiological groups of microorganisms and hence can `be replaced in biotechnological applications depending on the compatibility of the processes.

The Bond Strength and Antibacterial Activity of the Universal Dentin Bonding System: A Systematic Review and Meta-Analysis

Streptococcus mutans (S. mutans) is a group of viridans mostly located in oral flora among the wide and biodiverse biofilm. It plays a significant role not only in caries formation but also triggering intracerebral haemorrhage. The durable and stable bond interface, besides bacteria elimination, is one of the crucial factors influencing the resin composite restoration performance. This study aimed to evaluate universal adhesives (UAs) with regard to in vitro bond strength to dentin, and the inhibition of the S. mutans growth and compare them with UAs modified with antimicrobial agents through a systematic review and meta-analysis. Two reviewers performed a literature search up to April 2021 in 5 electronic databases: PubMed MedLine, Scielo, ISI Web of Science, Scopus, and EMBASE. Only in vitro studies reporting the effect of modifying UAs with antimicrobial agents on the bond strength to dentin and/or on the inhibition of the S. mutans were included. Analyses were carried out using Review Manager Software version 5.3.5 (The Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, Denmark). The methodological quality of each in vitro study was evaluated following the parameters of a previous systematic review. A total of 1716 potentially relevant publications were recognized. After reviewing the title and abstract, 16 studies remained in the systematic review. From these, a total of 3 studies were included in the meta-analysis. Since data from the studies included in the antimicrobial outcome included zero values, they could not be meta-analysed. Including 0 values in the analysis will lead to several biases in the analysis, so these data were discarded. The antibacterial effect against S. mutans of UAs modified with antimicrobial agents was higher than the non-modified adhesive systems. Within the limitations of the present study, the bond strength of UAs to dentin could be improved by using antimicrobial agents. The UAs modified with antibacterial agents showed a decrease in the viability of S. mutans biofilm, among the adhesives tested. However, there are not enough valid data on antibacterial properties of modified UAs; therefore, more well-designed research on these materials is needed.

Rapid detection of the Streptococcus mutans cnm gene by loop-mediated isothermal amplification

This study investigated a method using loop-mediated isothermal amplification (LAMP) for the rapid detection of cnm-positive Streptococcus mutans (S. mutans) associated with cerebral microhemorrhage. LAMP amplified the cnm gene plasmid vector, but not human or microbial genomic DNA. The cnm DNA of the cnm-positive S. mutans strain was detected in saliva without DNA extraction after 1 day of culture. This method resulted in a cnm-positive rate of 26.4% in 102 samples, which was higher than that obtained with conventional PCR. In conclusion, LAMP may be used for the detection of cnm-positive S. mutans in a large number of samples.

Use of Virtual Rehabilitation to Improve the Symmetry of Body Temperature, Balance, and Functionality of Patients with Stroke Sequelae

Background

Stroke rehabilitation that is based on the patients' needs, experiences, and priorities requires extensive knowledge and skills to capture and integrate the perspectives of the subject.

Purpose

The objective of this study was to evaluate the acute effect of an occupational therapy protocol associated with virtual reality (VR) on the symmetry of body temperature (BTP), balance, and functionality of patients with stroke sequelae.

Methods

Ten patients (69.84 ± 7.55 years) diagnosed with stroke between 2 and 10 years earlier were evaluated during clinical care sessions integrated with VR games. Associated with games, all patients were stimulated to use both upper and lower limbs and distribute body weight symmetrically, and perceptual stimuli of body-half training, alignment, postural control, and balance were given. The variables of thermography (temperature [°C] and body asymmetry) of the upper and lower limbs, balance (Berg scale), and functionality were analyzed before and after the test.

Results

BTP was reduced in the 4 upper and lower limb body regions of interest: the right arm (p = 0.024, Cohen's d = 1.02), previous direct hand (p = 0.034, Cohen's d = 1.22), right back hand (p = 0.003, Cohen's d = 1.85) and Left (p = 0.013, Cohen's d = 0.92), right thigh (p = 0.035, Cohen's d = 1.32), and left thigh (p = 0.047, Cohen's d = 0.92). The mean of the bilateral asymmetry variation of the arm in the anterior position at the pre test was classified according to the level of attention monitoring (which means that the asymmetry rate is above normal), changing its state at the end of the intervention to normal. There was an increase in the functional independence score (p = 0.015, Cohen's d = 0.50) and in the static and dynamic balance function (p = 0.001, Cohen's d = 0.07).

Conclusion

VR associated with occupational therapeutic planning can amplify and potentiate neurological recovery following stroke.