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1.
Dermatol Pract Concept ; 14(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38364388

RESUMO

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, I2 = 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.

2.
Biotechnol Adv ; 50: 107770, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33989704

RESUMO

In this review, we argue that there is much to be learned by transferring knowledge from research on lignocellulose degradation to that on plastic. Plastic waste accumulates in the environment to hazardous levels, because it is inherently recalcitrant to biological degradation. Plants evolved lignocellulose to be resistant to degradation, but with time, fungi became capable of utilising it for their nutrition. Examples of how fungal strategies to degrade lignocellulose could be insightful for plastic degradation include how fungi overcome the hydrophobicity of lignin (e.g. production of hydrophobins) and crystallinity of cellulose (e.g. oxidative approaches). In parallel, knowledge of the methods for understanding lignocellulose degradation could be insightful such as advanced microscopy, genomic and post-genomic approaches (e.g. gene expression analysis). The known limitations of biological lignocellulose degradation, such as the necessity for physiochemical pretreatments for biofuel production, can be predictive of potential restrictions of biological plastic degradation. Taking lessons from lignocellulose degradation for plastic degradation is also important for biosafety as engineered plastic-degrading fungi could also have increased plant biomass degrading capabilities. Even though plastics are significantly different from lignocellulose because they lack hydrolysable C-C or C-O bonds and therefore have higher recalcitrance, there are apparent similarities, e.g. both types of compounds are mixtures of hydrophobic polymers with amorphous and crystalline regions, and both require hydrolases and oxidoreductases for their degradation. Thus, many lessons could be learned from fungal lignocellulose degradation.


Assuntos
Lignina , Plásticos , Celulose , Fungos/genética
3.
Environ Microbiol ; 21(8): 2644-2658, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30815928

RESUMO

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.


Assuntos
Fusarium/metabolismo , Peróxido de Hidrogênio/metabolismo , NADPH Oxidases/metabolismo , Trichoderma/metabolismo , Evolução Biológica , Fusarium/crescimento & desenvolvimento , Hifas/crescimento & desenvolvimento , NADPH Oxidases/genética , Oxirredução , Trichoderma/enzimologia , Trichoderma/crescimento & desenvolvimento
4.
Zookeys ; (751): 1-40, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29706783

RESUMO

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.

5.
Biomed Res Int ; 2016: 5435397, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27652264

RESUMO

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.


Assuntos
Aspergillus/química , Nanopartículas Metálicas/química , Prata/química
6.
Environ Microbiol ; 18(2): 580-97, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26118314

RESUMO

Trichoderma guizhouense NJAU 4742 (Harzianum clade) can suppress the causative agent of banana wild disease Fusarium oxysporum f. sp. cubense 4 (Foc4). To identify genes involved in this trait, we used T-DNA insertional mutagenesis and isolated one mutant that was unable to overgrow Foc4 and had reduced antifungal ability. Using the high-efficiency thermal asymmetric interlaced-PCR, the T-DNA was located in the terminator of a neutral metalloprotease gene (encoding a MEROPS family M35 protease), which was named nmp1. The antifungal activity of the mutant was recovered by retransformation with wild-type nmp1 gene. The purified NMP1 (overexpressed in Pichia pastoris) did not inhibit the growth and germination of other fungi in vitro. Its addition, however, partly recovered the antifungal activity of the mutant strain against some fungi. The expression of nmp1 is induced by the presence of fungi and by dead fungal biomass, but the time-course of transcript accumulation following the physical contact depends on mode of interaction: it increases in cases of long-lasting parasitism and decreases if the prey fungus is dead shortly after or even before the contact (predation). We thus conclude that NMP1 protein of T. guizhouense has major importance for mycotrophic interactions and defence against other fungi.


Assuntos
Antifúngicos/metabolismo , Fusarium/patogenicidade , Metaloproteases/genética , Metaloproteases/metabolismo , Trichoderma/genética , Trichoderma/metabolismo , DNA Bacteriano/genética , Musa/microbiologia , Mutagênese Insercional , Pichia/genética , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase , Transformação Genética
7.
Jundishapur J Microbiol ; 8(1): e13720, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25763132

RESUMO

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.

8.
Jundishapur J Microbiol ; 8(1): e12269, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25789120

RESUMO

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.

9.
J Dent (Tehran) ; 10(4): 329-37, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-24396352

RESUMO

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-ß-nepetalactone (55-58%), and 4a-α, 7-ß, 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.

10.
ISRN Pharm ; 2012: 591953, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22779012

RESUMO

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-α,7-α,7a-ß-nepetalactone (55-58%) and 4a-α,7-ß,7a-α-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.

11.
Nat Prod Commun ; 6(8): 1173-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21922929

RESUMO

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.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Óleos Voláteis/química , Óleos de Plantas/química , Satureja/química , Satureja/crescimento & desenvolvimento , Antifúngicos/química , Antifúngicos/farmacologia , Sementes/química
12.
J Microbiol Methods ; 85(3): 233-4, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21443912

RESUMO

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.


Assuntos
Proteínas Hemolisinas/metabolismo , Hemólise , Streptococcus pyogenes/enzimologia , Streptococcus pyogenes/isolamento & purificação , Ágar , Meios de Cultura/química , Humanos , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/microbiologia
13.
J Glob Infect Dis ; 3(4): 357-60, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22223999

RESUMO

CONTEXT: Candida species are opportunistic yeasts that cause infections ranging from simple dermatosis to potentially life-threatening 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.

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