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The chemical composition of the essential oil of Lindera subumbelliflora (Lauraceae) was investigated for the first time. The essential oil was obtained by hydrodistillation and fully characterised by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The antifungal activity of L. subumbelliflora essential oil was tested against Candida albicans and Streptococcus mutans using the broth microdilution assay, whereas the microbial biofilms were determined using a semi-quantitative static biofilm. A total of 28 components (99.6%) were successfully identified, which were characterised by β-eudesmol (14.6%), cis-α-bergamotene (11.0%), α-copaene (8.5%), dodecen-1-ol (8.5%), and (E)-nerolidol (8.3%). The essential oil exhibited activity against Candida albicans and Streptococcus mutans with MIC values of 250 and 500 µg/mL, respectively. The essential oil increased the biofilm of Candida albicans by 38.25%, however, decreased the biofilm of Streptococcus mutans by 47.89% when treated with 500 µg/mL. Thus, the essential oil has a promising application in dentistry via inhibition of the growth of Candida albicans and Streptococcus mutans. However, the antibiofilm activity of the essential oil is only applicable for cariogenic Streptococcus mutans. [ABSTRACT FROM AUTHOR]

Essential oils, a volatile mixture derived from plants, have shown a wide biological activity, and have been used as ancient remedies for the treatment of various diseases. The objective of this study was to investigate the chemical composition and cytotoxicity of the essential oil obtained from Garcinia urophylla leaves collected from Malaysia. Eighteen components were identified using gas chromatography-flame ionisation detection (GC-FID) and gas chromatography/mass spectrometry (GC-MS), which represent 99.9% of the essential oil. The major components were β-caryophyllene (56.2%), α-humulene (26.3%), and α-gurjunene (6.3%). The cytotoxicity of essential oil was evaluated using an MTT assay. The essential oil exhibited cytotoxicity against three cancer cell lines which are HepG2, MCF7, and A549 with the IC50 values of 71.5, 56.2, and 68.5 μg/mL, respectively. To the best of our knowledge, this is the first report on the essential oil composition obtained from Garcinia urophylla, which may have implications on the pharmaceutical and therapeutic applications of Garcinia genus essential oils. [ABSTRACT FROM AUTHOR]

Oral carcinogenesis is preceded by oral diseases associated with inflammation such as periodontitis and oral candidiasis, which are contributed by chronic alcoholism, smoking, poor oral hygiene, and microbial infections. Dysbiosis is an imbalance of microbial composition due to oral infection, which has been reported to contribute to oral carcinogenesis. Therefore, in this review, we summarised the role of probiotics, prebiotics, synbiotics, and postbiotics in promoting a balanced oral microbiome, which may prevent oral carcinogenesis due to oral infections. Probiotics have been shown to produce biofilm, which possesses antibacterial activity against oral pathogens. Meanwhile, prebiotics can support growth and increase the benefit of probiotics. In addition, postbiotics possess antibacterial, anticariogenic, and anticancer properties that potentially aid in oral cancer prevention and treatment. The use of probiotics, prebiotics, synbiotics, and postbiotics for oral cancer management is still limited despite their vast potential, thus, discovering their prospects could herald a novel approach to disease prevention and treatment while participating in combating antimicrobial resistance. [ABSTRACT FROM AUTHOR]

Oral biofilms comprise extracellular polysaccharides and polymicrobial microorganisms. The objectives of the study were to characterize the deer velvet antler (DVA) compounds and their effect on Candida species biofilm formation with the hypothesis that DVA inhibits the biofilm of Candida spp. Liquid Chromatography-Quadrupole Time of Flight-Mass Spectrometry (LC-QTOF-MS) was conducted to characterize the DVA compounds. To study the effect of DVA on biofilm, Candida albicans ATCC MYA-4901 (ALT5), AIDS isolate (ALC2), oral cancer isolate (ALC3), C. dubliniensis ATCC MYA-2975, C. glabrata ATCC 90030 , C. krusei 14   243 , C. lusitaniae ATCC 34449 , C. parapsilosis ATCC 22019, and C. tropicalis ATCC 13803 were inoculated with DVA in separate wells of a 96-well plate containing RPMI-1640 followed by 72 h incubation. A total of 45 compounds were detected in the DVA extract. C. lusitaniae exhibited a higher percentage of biofilm biomass reduction when treated with DVA extract (66.10% ± 5.33), followed by ALC3 (44.12% ± 6.24). However, C. glabrata, C. krusei , and C. parapsilosis showed no reduction in biofilm biomass after being treated with DVA extract. Most Candida strains also exhibited decreased total cell count when treated with DVA extract, except for ALC3 and C. krusei. ALT5 had the lowest total cell count (0.17 × 105 cells/ml) when cultured with DVA extract. In conclusion, DVA extract inhibits Candida spp. biofilm formation except for C. glabrata, C. krusei , and C. parapsilosis. [ABSTRACT FROM AUTHOR]

It is estimated that 48% of children globally and over 70% of those in Malaysia suffer from early childhood caries (ECC). This review aimed to systematically gather studies on ECC and determine key factors associated with it using bibliometric analysis. The "early childhood caries" keyword was searched in the Scopus database. A total of 1,984 articles were selected based on the selection criteria. Author, country, document and keyword analysis was done using VOSviewer 1.6.19. The United States is the leading country in ECC research. The bibliometric analysis of keywords showed seven clusters and the keywords were further ranked according to the risk factors. Dental care was the main key factor of ECC, followed by microbiome, diet and socioeconomic. This insight highlights the emphasis on understanding and addressing issues related to dental care practices in the context of preventing and managing ECC. It is a disease of multifactorial aetiology. Hence, prevention might still be the best way forward. [ABSTRACT FROM AUTHOR]

Individuals with a history of coronavirus disease 2019 (COVID-19) exhibit memory immunity acquired during natural infection. However, a decline in immunity after infection renders these individuals vulnerable to re-infection, in addition to a higher risk of infection with new variants. This systematic review examined related studies to elucidate the antibody response in these infected individuals after messenger ribonucleic acid (mRNA) vaccination. Hence, the focus of this review was to ascertain differences in the concentration of binding and neutralising antibodies of previously infected individuals in comparison to those of infection-naïve individuals after administration of two doses of mRNA vaccination through available case-control and cohort studies. Positive reverse transcriptase-polymerase chain reaction (RT-PCR) test or detectable anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies at the baseline in included studies showed categorisation of infected and uninfected individuals. This review utilised three online databases: PubMed, Scopus and Cochrane with the following keywords: (COVID-19 OR 'Coronavirus Disease 2019' OR SARS-CoV-2) AND Immun* AND (Pfizer OR BioNTech OR BNT162b2 OR Comirnaty OR Moderna OR mRNA-1273) from January 2019 to July 2021. Following the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocol (PRISMA-P) 2020 guidelines and assessment based on the Crowe Critical Appraisal Tool (CCAT), we included 13 related qualified papers of observational studies discerning the binding and neutralising antibody concentrations of infected and uninfected individuals after administration of mRNA vaccines, such as the BNT162b2 and mRNA-1273 vaccine. The mRNA vaccines induced robust binding and neutralising antibody responses in both groups. However, infected individuals showed induction of higher antibody responses in a shorter time compared to uninfected individuals. Hence, a single dose of mRNA vaccination for infected individuals may be sufficient to reach the same level of antibody concentration as that observed in uninfected individuals after receiving two doses of vaccination. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has had a significant impact globally. Healthcare workers (HCWs) were forced to work with uncertainties about the virus, extended working hours, and increasing cases. It is known that stress causes immunosuppression, and salivary IgA (sIgA) is the immune marker most strongly related to work stress. However, the relationship between stress level, COVID-19 fear, and immunosuppression was unknown. The study investigated the relationship between COVID-19-related fear and stress of the sIgA level. A cross-sectional study was conducted among 109 staff nurses in SASMEC, Kuantan, Pahang. Stratified randomised sampling was done for selection of participants. The PSS-10 and FCV -19S-M Questionnaires were administered to objectively assess stress and fear, followed by non-invasive saliva sample collection. Quantitative measurement of IgA level was done using an Enzyme- linked Immunosorbent Assay Kit (ELISA) for sIgA. Pearson correlation test and coefficient of determination (R2) were applied. 86% of participants were female, 83% were aged between 26-45 years old, 75% were married, 95% had worked for more than 1 year, and 68% worked in high-risk stations. The majority of the participants scored moderate severity in terms of perceived stress (84%) and fear level (61%), and the mean sIgA level was 3.96ng/mL. Further analysis showed no linear correlation between stress and fear with salivary IgA levels. Conclusion: HCWs are inevitably exposed to high stress, especially during the pandemic, not just work-related stress and COVID exposure but also other demographic and situational factors. Though the current study revealed moderate stress and fear levels among the staff nurses with no significant association between salivary IgA and stress and fear, further study should examine other factors such as coping skills, working environment, and protective factors that may modify perceived stress and, subsequently, immunological response. [ABSTRACT FROM AUTHOR]