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When resources are limited, the hypocrealean fungus Trichoderma guizhouense can overgrow another hypocrealean fungus Fusarium oxysporum, cause sporadic cell death and arrest growth. A transcriptomic analysis of this interaction shows that T. guizhouense undergoes a succession of metabolic stresses while F. oxysporum responded relatively neutrally but used the constitutive expression of several toxin-encoding genes as a protective strategy. Because of these toxins, T. guizhouense cannot approach it is potential host on the substrate surface and attacks F. oxysporum from above. The success of T. guizhouense is secured by the excessive production of hydrogen peroxide (H2 O2 ), which is stored in microscopic bag-like guttation droplets hanging on the contacting hyphae. The deletion of NADPH oxidase nox1 and its regulator, nor1 in T. guizhouense led to a substantial decrease in H2 O2 formation with concomitant loss of antagonistic activity. We envision the role of NOX proteins in the antagonism of T. guizhouense as an example of metabolic exaptation evolved in this fungus because the primary function of these ancient proteins was probably not linked to interfungal relationships. In support of this, F. oxysporum showed almost no transcriptional response to T. guizhouense Δnox1 strain indicating the role of NOX/H2 O2 in signalling and fungal communication.

Aim: the aim of the present systematic review and meta-analysis was evaluate the levels changes of periodontal pathogens in children during orthodontic treatments. Method: From the electronic databases, PubMed, Cochrane Library, Embase, ISI have been used to perform a systematic literature until September 2020. Therefore, a software program (Endnote X8) has been utilized for managing the electronic titles. Searches were performed with mesh terms. Odds ratio between before and one or three months after treatment with 95% confidence interval (CI), Mantel-Haenszel method were calculated. Random effects were used to deal with potential heterogeneity and I² showed heterogeneity. The Meta analysis and forest plots have been evaluated with the use of a software program available in the market (i.e., Comprehensive Meta-Analysis Stata V16). Result: A total of 46 potentially relevant titles and abstracts were found during the electronic and manual search. Finally, a total of three publications fulfilled the inclusion criteria required for this systematic review. Odds ratio of P.gingivalis was (OR, -0.58 95% CI -1.34, 0.18. P= 0.14) and Odds ratio of T. forsythensis was (OR, -1.44 95% CI -2.16, 0.73. P= 0.00), also odds ratio of P. intermedia was (OR, -1.09 95% CI -2.09, -0.10. P= 0.03). Conclusion: The present systematic review and met analysis showed the levels of periodontal pathogens in children during orthodontic treatments was increased after orthodontic treatments vs before orthodontic treatments. Only no change in P.gingivalis was observed. [ABSTRACT FROM AUTHOR]

A taxonomic description of all castes of Colobopsis explodens Laciny & Zettel, sp. n. from Borneo, Thailand, and Malaysia is provided, which serves as a model species for biological studies on "exploding ants" in Southeast Asia. The new species is a member of the Colobopsis cylindrica (COCY) group and falls into a species complex that has been repeatedly summarized under the name Colobopsis saundersi (Emery, 1889) (formerly Camponotus saundersi). The COCY species group is known under its vernacular name "exploding ants" for a unique behaviour: during territorial combat, workers of some species sacrifice themselves by rupturing their gaster and releasing sticky and irritant contents of their hypertrophied mandibular gland reservoirs to kill or repel rivals. This study includes first illustrations and morphometric characterizations of males of the COCY group: Colobopsis explodens Laciny & Zettel, sp. n. and Colobopsis badia (Smith, 1857). Characters of male genitalia and external morphology are compared with other selected taxa of Camponotini. Preliminary notes on the biology of C. explodens Laciny & Zettel, sp. n. are provided. To fix the species identity of the closely related C. badia, a lectotype from Singapore is designated. The following taxonomic changes within the C. saundersi complex are proposed: Colobopsis solenobia (Menozzi, 1926), syn. n. and Colobopsis trieterica (Menozzi, 1926), syn. n. are synonymized with Colobopsis corallina Roger, 1863, a common endemic species of the Philippines. Colobopsis saginata Stitz, 1925, stat. n., hitherto a subspecies of C. badia, is raised to species level. [ABSTRACT FROM AUTHOR]

Foods provide a natural and perfect medium for bacteria and fungi to multiply and growth. Awareness of people of synthetic additives and preservatives in food processing has led food industries to search for natural additives with a broad spectrum of antimicrobial activities. The chemical compositions of the essential oils (EOs) distilled from threeSaturejaspp. have been analyzed by gas chromatography-mass spectrometry (GC-MS). The antimicrobial activities of the EOs against microorganisms causing food-borne infections were determined by the broth micro-dilution method as recommended by the Clinical and Laboratory Standards Institute (CLSI). Analysis of the EOs showed that phenolic compound including thymol and carvacrol are the main components of the EOs. Inhibition studies indicated that the tested EOs entirely inhibited the growth of tested fungi at concentrations of less than 0.062 μl/mL. Moreover, the oils exhibited significant bacteriostatic and bactericidal activities against Gram-positive and Gram-negative bacteria at concentrations ranging from 0.031–1 μL/mL. Considering the wide range of antimicrobial activities of the examined EOs, they might have potential to be used in food industry as a natural preservative agent and to extend the shelf life of products. [ABSTRACT FROM AUTHOR]

Along with the popularity of raw sprouts in the food baskets, the outbreaks associated with the consumption of the contaminated sprouts increased. In the present study, the antibacterial effect of the essential oil of Satureja khuzistanica in reducing the Escherichia coli O157: H7 population on alfalfa seeds prior to sprouting was evaluated. The essential oil ( EO) was analyzed by gas chromatography/mass spectrometry. Alfalfa seeds were inoculated with E. coli O157: H7. The inoculated seeds were then treated with different concentrations of the essential oil of S. khuzistanica. The surviving populations of E. coli O157: H7 were enumerated by direct plating of the seeds on tryptic soy agar. The oil was rich in carvacrol. Direct surface-plating on selective media showed the treatment resulted in a significant ( P ≤ 0.05) reduction of E. coli O157: H7 population in a dose-dependent manner. Increasing the washing time revealed a significant effect on reduction of E. coli O157: H7 population. The considerable antibacterial activity of the oil might be due to the high concentration of carvacrol. As the S. khuzistanica EO did not adversely affect alfalfa seed germination and had a strong antibacterial activity, the oil might be used as a natural antimicrobial product to overcome bacterial contamination of sprouts without compromising the viability. Practical Application During the past decades, existing of chemical antibacterial has become increasingly unpopular in food industries. Consumers presume that these chemicals are threats to human health, because of their carcinogenicity, allergenicity, toxicity and environmental contaminations. For these reasons, nowadays, using of organic products is becoming more popular. Moreover, many foodborne pathogens are genetically adapted to synthetic antimicrobial compounds, thereby reducing the efficacy of such preventatives. It has been known that EOs have antimicrobial activities, rendering these natural products as good alternatives to synthetic bactericides. S. khuzistanica, with high concentration of carvacrol which is classified as GRAS (generally regarded as safe), could be one of these potential alternatives. This antimicrobial property favors its application in food industries as a reasonably safe agent. The confirmed antibacterial activities of S. khuzistanica, recommends its possible application in the field of food preservation for prolonging the shelf life of sprouts during postharvest and marketing processes. [ABSTRACT FROM AUTHOR]

Nosocomial pathogens are associated with increased hospital stay lengths and mortality rates. Increasing resistance to antibiotics makes the treatment of these infections more difficult. Novel antimicrobial compounds derived from natural sources may be useful for addressing antiobiotic resistance. The objective of this study is to determine the chemical composition and antimicrobial activities of essential oils from Myrtus communis L. (Myrtaceae) leaves against pathogens causing nosocomial infections. The chemical composition of essential oil from M. communis leaves was analysed by gas chromatography-mass spectrometry (GC-MS). The antimicrobial activity of the essential oil against bacteria and fungi was evaluated by broth micro-dilution as per the Clinical and Laboratory Standards Institute (CLSI) methods. GC-MS analysis revealed that the major constituents of the essential oil were α-pinene (39.2%), 1,8-cineole (22.0%), and linalool (18.4%). The essential oil exhibited antimicrobial activity against all Gram positive and Gram negative bacteria with MICs in the range of 0.5-32 μL/mL and 8-64 μL/mL, respectively. MICs for the tested clinical and standard fungi were in the range of 0.03-16 μL/mL. The essential oil exhibited strong antibacterial and antifungal activities against all the causative agents of nosocomial infections examined, particularly against strains with antibiotic resistance. The essential oil from M. communis leaves is a potential source of novel antimicrobial agents for the treatment of nosocomial infections. [ABSTRACT FROM AUTHOR]

Context: Candida species are opportunistic yeasts that cause infections ranging from simple dermatosis to potentially lifethreatening fungemia. The emergence of resistance to antifungal drugs has been increased in the past two decades. Aim: the present study we determined to find out the susceptibility profiles of clinical isolates of Candida species against four antifungal drugs, including amphotericin B, ketoconazole, fluconazole and itraconazole. Materials and Methods: Antifungal susceptibility testing of the yeasts was done in accordance with the proposed guidelines for antifungal disk diffusion susceptibility testing of yeasts based on the CLSI document M44-A. Results: A total of 206 yeast isolates were assessed. Among the evaluated Candida species, the highest rates of resistance to ketoconazole were seen in Candida glabrata (16.6%) and Candida albicans (3.2%). Susceptibility and intermediate response to fluconazole were seen in 96.6% and 3.4% of the Candida isolates, respectively. A total of 19 (9.2%) yeast isolates showed petite phenomenon including 11 C. glabrata, 3 C. albicans, 2 Candida dubliniensis and one isolate of each Candida krusei and Candida parapsilosis. Conclusion: The high number of petite mutation in the isolated yeasts should be seriously considered since it may be one of the reasons of antifungal treatment failure. [ABSTRACT FROM AUTHOR]

Introduction: Recurrent aphthous stomatitis (RAS) is a prevalent ulcerative condition affecting oral mucosa., Objectives: A systematic review and meta-analysis was performed to compare the level of neutrophil to lymphocyte ratio (NLR) between individuals with RAS and those who are healthy., Methods: A systematic search for relevant publications before June 21, 2022, was conducted using Web of Science, PubMed, and Scopus. The results were presented as the standardized mean difference (SMD) with a 95% confidence interval (CI), and a random-effects model was used to calculate pooled effects due to the presence of significant heterogeneity. Quality assessment was performed using the Newcastle-Ottawa scale., Results: Overall, 13 article with were included in the analysis. NLR was higher among patients with RAS compared to healthy controls (SMD = 0.50, 95% CI = -0.20 to 0.79, P = 0.001, I 2 = 91.5%). In the subgroup analysis based on the study design, it was found that retrospective studies showed higher levels of NLR in patients with RAS compared to healthy controls (SMD = 0.62, 95% CI= 0.16 to 1.08, P < 0.01), but these results were not applied to prospective studies (SMD = 0.35, 95% CI = -0.03 to 0.74, P < 0.07)., Conclusion: Elevated neutrophil to lymphocyte ratio revealed crosstalk between systematic inflammation and RAS.

Objectives: Over the past two decades, there has been a growing trend in using oral hygienic products from natural resources such as essential oils and plant extracts. Nepeta cataria L. is a member of the mint family (Labiatae) with several medicinal properties. The objective of this study was to determine the chemical composition and antimicrobial activities of essential oils (EOs) from N. cataria leaves against pathogens causing oral infections., Materials and Methods: The chemical composition of EOs from N. cataria was analyzed by gas chromatography/mass spectrometry (GC/MS). The antimicrobial activity of the essential oil was evaluated by broth micro-dilution in 96 well plates as recommended by the Clinical and Laboratory Standards Institute (CLSI) methods. The plates were incubated at 30°C for 24-48 h (fungi) or at 37°C for 24 h (bacteria)., Results: The analysis of the EOs indicated that 4a-α, 7-α, 7a-β-nepetalactone (55-58%), and 4a-α, 7-β, 7a-α-nepetalactone (30-31.2%) were the major compounds of the EOs at all developmental stages. The tested EOs exhibited antimicrobial activities against the tested bacteria at concentrations of 0.125-4 μL/mL. Moreover, the oils entirely inhibited the growth of Candida species at a concentration less than 1 μL/mL., Conclusion: Based on these results, the EO of N. cataria can possibly be used as an antimicrobial agent in the treatment and control of oral pathogens.