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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.

One of the best ways to obtain TiN coatings is through the nitriding process by efficient methods such as dense plasma focus (DPF). The gas composition of the nitrogen environment is a crucial factor affecting the properties of the coating. In this study, three different atmospheres of 100%N2, 50%N2–50%O2, and 75%N2–25%Ar were used to investigate their impact on the mechanical and biological properties of TiN coatings on NiTi substrate. The operating condition that yielded the coating with the highest hardness, as well as the lowest contact angle and Ni ion release, was chosen as the optimum condition. According to the XRD results, TiN was recognized as the dominant phase which causes high hardness and prevents Ni ion release. Moreover, surface analyses determined that the sample coated in 50%N2 composition possessed higher hardness and as a result displayed better mechanical properties. Also, the improved microstructural properties lead to an enhanced coating/substrate adhesion strength. On the other hand, the reaction of TiO2 and TiN lead to the formation of TiN0.6O0.4 ternary compound and for this reason, the 50%N2–50%O2 sample exhibited better performance in preventing the release of the toxic nickel ion compared to the other samples. Finally, due to the presence of TiO2 and TiN0.6O0.4 in the sample surface treated at 50%N2–50%O2, better hydrophilicity was observed compared to other samples. Results confirm that the applied surface modification method is effective in increasing the mechanical and biological properties of the NiTi, where it may open numerous possibilities for efficient use in orthopedic applications. [ABSTRACT FROM AUTHOR]

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]

Currently, researchers turn to natural processes such as using biological microorganisms in order to develop reliable and ecofriendly methods for the synthesis of metallic nanoparticles. In this study, we have investigated extracellular biosynthesis of silver nanoparticles using four Aspergillus species including A. fumigatus, A. clavatus, A. niger, and A. flavus. We have also analyzed nitrate reductase activity in the studied species in order to determine the probable role of this enzyme in the biosynthesis of silver nanoparticles. The formation of silver nanoparticles in the cell filtrates was confirmed by the passage of laser light, change in the color of cell filtrates, absorption peak at 430 nm in UV-Vis spectra, and atomic force microscopy (AFM). There was a logical relationship between the efficiencies of studied Aspergillus species in the production of silver nanoparticles and their nitrate reductase activity. A. fumigatus as the most efficient species showed the highest nitrate reductase activity among the studied species while A. flavus exhibited the lowest capacity in the biosynthesis of silver nanoparticles which was in accord with its low nitrate reductase activity. The present study showed that Aspergillus species had potential for the biosynthesis of silver nanoparticles depending on their nitrate reductase activity. [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]

Nepeta cataria L. is traditionally consumed as a food additive. The effects of three different harvest stages of N. cataria essential oils (EOs) against most common causes of food-borne infections were evaluated by broth microdilution method as recommended by the Clinical and Laboratory Standards Institute (CLSI). The chemical composition of the EOs from N. cataria has been analyzed by gas chromatography/mass spectrometry (GC/MS). The analysis of the EOs indicated that 4a-a,7-a,7a-ß-nepetalactone (55-58%) and 4a-a,7-ß,7a-a-nepetalactone (30-31.2%) were the major compounds of the EOs at all developmental stages. The results showed that the tested EOs exhibited antimicrobial activities against the food-borne pathogens at concentrations of 0.125- 2 µL/mL. Based on these results, the EO of N. cataria can possibly be used in food products as a natural preservative agent [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]

Abstract: The aim of the study was to assess the reliability of human blood agar media (HuBA) in identifying Streptococcus pyogenes by hemolysis analysis. We analyze several factors that might affect the accuracy of HuBA media for microbial analysis, including incubation time, blood group, Rh factor and presence of antistreptolysin-o. [Copyright &y& Elsevier]

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.

Background: Essential Oils (EOs) possess antibacterial properties and represent a natural source to treat infections and prevent food spoilage. Their chemical composition might be affected by the environmental condition and the developmental growth stages of the plant., Objectives: The current study aimed to determine the variations in chemical compositions and antimicrobial activities of the EOs of Ocimum sanctum L. at different stages of harvesting., Materials and Methods: The oils constituents were analyzed by gas chromatography/mass spectrometry (GC/MS). The effects of three different harvest stages of O. sanctum EOs against most common causes of food-borne were evaluated by broth micro-dilution method as recommended by the Clinical and Laboratory Standards Institute (CLSI)., Results: The analysis of the EOs indicated that eugenol was the major compound of the EOs at all developmental stages which reached its maximum level at the second stage. The results showed that the tested EOs exhibited antimicrobial activities against all of the examined pathogens at concentrations of 0.125-32 µL/mL, except Pseudomonas aeruginosa which was only inhibited by high concentrations of the floral budding and full flowering EOs. EO distilled from the second developmental growth stage (floral budding) of O. sanctum exhibited the strongest antibacterial activities against the food borne bacteria., Conclusions: Considering the wide range of antimicrobial activities of the examined EOs, they might have the potential to be used to manage infectious diseases or extend the shelf life of food products.

Background: Anabolic-androgenic steroids (AAS) abuse by the athletes has dramatically increased during the recent decades. These substances might increase the skin lipids and enhance the cutaneous microbial proliferation., Objectives: The current study aimed to investigate the potential side effects of AAS on the bacterial microflora colonization of the bodybuilders` skin., Patients and Methods: The skin samples of 94 male bodybuilders (71 AAS users, 23 non-AAS users) and 46 subjects of the control group, with similar gender and age, were cultured and incubated in both aerobic condition to isolate Staphylococcus aureus and anaerobic condition for Propionibacterium acnes. The isolated bacteria were identified by standard microbiological techniques., Results: The skin lesions were more frequent in the body builders than the controls. Moreover, statistically significant differences were also observed in skin lesions among the AAS users and the non-AAS user athletes. The prevalence of S. aureus and P. acnes in the athletes was higher than that of the control group. In addition, there was a significant difference in distribution of P. acnes between the bodybuilders who used AAS and those who did not., Conclusions: A higher number of bacterial flora was found in the bodybuilders particularly those using AAS in comparison to the controls, which might be due to the influence of these AAS on the skin microflora and transmission of the bacteria through the direct contact of the naked skin with the exercise instruments.

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.

The variations in quantity and quality of essential oils (EOs) from the aerial parts of cultivated Satureja hortensis were determined at different stages of harvesting. The EOs of air-dried samples were obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry (GC/MS). The antimicrobial activity of the EOs was investigated by broth microdilution methods. The amount of EOs (w/w, %) were 2.3, 2.5, 2.0, and 1.8% at floral budding, full flowering, immature fruit, and ripened fruit stages, respectively. gamma-Terpinene was the major compound of the EO at all developmental stages, except the ripened fruit stage when it was replaced by carvacrol (46.4%). The EOs exhibited strong antibacterial activities against the tested bacteria. Moreover, the EOs either inhibited or killed the examined yeasts at concentrations ranging from 0.03-8.0 microL/mL. Considering the wide range of antimicrobial activities of the examined EOs, they might have potential to be used in the management of infective agents.