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1.
World J Microbiol Biotechnol ; 40(1): 6, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37932532

RESUMO

Urinary tract infections (UTIs) are a significant cause of morbidity in healthcare systems and are prominently associated with applying urethral catheters, particularly in surgeries. Polyvinyl chloride (PVC) is extensively utilized in the fabrication of catheters. Biofilms, complex polymeric constructions, provide a protective milieu for cell multiplication and the enhancement of antibiotic resistance. Strategies to counteract biofilm development on medical apparatuses' surfaces incorporate antimicrobial agents such as N,N-dodecyl, and methyl polyethylenimine (DMPEI). This research endeavored to characterize the morphology of PVC and PVC-DMPEI surfaces utilizing Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) and to gauge hydrophobicity through contact angle measurements. Employing Escherichia coli, Staphylococcus aureus, and Candida albicans in adhesion assays enabled the assessment of DMPEI's efficacy in preventing microbial adherence to PVC. Butanol successfully solubilized 2 mg.mL-1 DMPEI without altering the PVC structure. SEM results substantiated the formation of a DMPEI layer on the PVC surface, which led to decreased surface roughness, as validated by AFM, and increased hydrophilicity, as demonstrated by contact angle evaluations. E. coli, S. aureus, and C. albicans exhibited significant adhesion reduction, 89.3%, 94.3%, and 86.6% on PVC-DMPEI surfaces. SEM visualizations confirmed reduced cellular colonization on PVC-DMPEI and highlighted considerable morphological modifications in E. coli. Consequently, DMPEI films effectively minimize the adhesion of E. coli, S. aureus, and C. albicans on PVC surfaces. DMPEI, with its potential as a protective coating for innovative medical devices, promises to inhibit biofilm adherence effectively.


Assuntos
Escherichia coli , Polietilenoimina , Polietilenoimina/farmacologia , Staphylococcus aureus , Catéteres , Biofilmes , Candida albicans
2.
Insects ; 14(9)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37754694

RESUMO

Euwallacea perbrevis, the tea shot-hole borer (TSHB), is an invasive ambrosia beetle that vectors several fungal pathogens that cause Fusarium branch dieback in avocado trees in southern Florida. This study assessed the potential of four commercial products containing the entomopathogenic fungus Beauveria bassiana (Bb) for managing adult TSHB beetles. Formulated products containing Bb strains to which adult beetles were exposed were BioCeres WP, BotaniGard WP, BotaniGard ES, and Velifer ES. Controls consisted of water only and BotaniGard ES and Velifer ES supernatant with spores removed. Acquisition of spores by adult beetles dipped in product suspensions with 2.5 ± 0.1 × 106 spores/mL was assessed. Survival time of beetles after residual exposure to the Bb-based products in an in vivo avocado bark plug bioassay was determined. Production of Bb spores on beetles after being dipped in product suspensions and placed in a moistened bark-plug assay with water only was assessed. Significantly more spores were acquired by beetles exposed to Velifer ES and BotaniGard ES than beetles exposed to the other fungal products. Beetles exposed to Velifer ES and BotaniGard ES died faster (6-8 days) compared to beetles dipped in the other fungal products (10-11 days) and controls (12 days). Percentage of mycosis was highest with beetles exposed to Velifer ES (63%). Spore production on cadavers of beetles dipped in Velifer ES (20 ± 6.4 × 105 spores/cadaver) was the highest among all treatments, whereas it was the lowest on cadavers of beetles dipped in BotaniGard ES (1 ± 0.2 × 105 spores/cadaver). All Bb-based products, especially Velifer ES, demonstrated potential to manage TSHB populations under laboratory conditions. These Bb-based fungal products should be tested under field conditions to confirm these laboratory results.

3.
Front Microbiol ; 14: 1110474, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937297

RESUMO

Introduction: Ambrosia beetles maintain strict associations with specific lineages of fungi. However, anthropogenic introductions of ambrosia beetles into new ecosystems can result in the lateral transfer of their symbionts to other ambrosia beetles. The ability of a Florida endemic ambrosia beetle, Xyleborus bispinatus, to feed and establish persistent associations with two of its known symbionts (Raffaelea subfusca and Raffaelea arxii) and two other fungi (Harringtonia lauricola and Fusarium sp. nov.), which are primary symbionts of invasive ambrosia beetles, was investigated. Methods: The stability of these mutualisms and their effect on the beetle's fitness were monitored over five consecutive generations. Surface-disinfested pupae with non-developed mycangia were reared separately on one of the four fungal symbionts. Non-treated beetles (i.e., lab colony) with previously colonized mycangia were used as a control group. Results: Xyleborus bispinatus could exchange its fungal symbionts, survive, and reproduce on different fungal diets, including known fungal associates and phylogenetically distant fungi, which are plant pathogens and primary symbionts of other invasive ambrosia beetles. These changes in fungal diets resulted in persistent mutualisms, and some symbionts even increased the beetle's reproduction. Females that developed on Fusarium sp. nov. had a significantly greater number of female offspring than non-treated beetles. Females that fed solely on Harringtonia or Raffaelea symbionts produced fewer female offspring. Discussion: Even though some ambrosia beetles like X. bispinatus can partner with different ambrosia fungi, their symbiosis under natural conditions is modulated by their mycangium and possibly other environmental factors. However, exposure to symbionts of invasive beetles can result in stable partnerships with these fungi and affect the population dynamics of ambrosia beetles and their symbionts.

4.
Biomolecules ; 12(1)2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-35053245

RESUMO

Euwallacea perbrevis is an ambrosia beetle that vectors fungal pathogens causing Fusarium dieback in Florida avocado trees. Current monitoring lures contain quercivorol, a fungus-produced volatile, but the exact attractant is unknown since lures contain a mixture of p-menth-2-en-1-ol isomers and both α- and ß-phellandrene. This study used pure cultures of six symbiotic fungi isolated from E. perbrevis to document volatile emissions and determine the relative attraction of symbionts in binary choice assays. In a comparative test, headspace solid-phase microextraction followed by gas chromatography-mass spectroscopy was used to identify and quantify emissions from 3-week-old cultures. In a temporal study, Super-Q collection followed by gas chromatography-flame ionization detection was used to measure cis- and trans-p-menth-2-en-1-ol emissions for three months. A total of 15 compounds were detected, with monoterpene hydrocarbons and oxygenated monoterpenoids predominating. Only trans-p-menth-2-en-1-ol was common to all six symbionts. Peak levels of both isomers were observed at day 7, then gradually declined over a 90 day period. In choice tests, avocado sawdust disks inoculated with Fusarium sp. nov. were the most attractive. This symbiont produced only two volatiles, trans-p-menth-2-en-1-ol and limonene. The combined results indicate that trans-p-menth-2-en-1-ol is the primary female attractant emitted from symbiotic fungi, but limonene may be a secondary attractant of E. perbrevis.


Assuntos
Besouros , Fusarium , Persea , Gorgulhos , Animais , Besouros/microbiologia , Feminino , Chá
6.
Ann Gastroenterol ; 34(4): 582-587, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34276199

RESUMO

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP) is frequently performed in the prone or supine position. We compared the technical success and other outcomes between these positions. METHODS: This was a retrospective cohort study using the Clinical Outcomes Research Initiative database. Demographics, procedure and fluoroscopy time, visualization of main structures, and technical success rates were compared between the supine and prone positions. Univariate and multivariate regressions were performed to adjust for age, sex, ethnicity and clinical setting. RESULTS: A total of 21,090 patients who underwent ERCP were included, of whom 1769 (8.4%) were supine and 19,321 (91.6%) were prone. The common bile duct (CBD) was visualized and cannulated in 89.1% of supine vs. 91.4% of prone positions (P=0.017), while the ampulla was visualized in 97.1% of supine vs. 97.7% of prone (P=0.414). The ERCP was incomplete in 10% of supine vs. 5% of prone cases (P<0.001). On multivariate analysis, supine position required shorter procedure times than prone (adjusted odds ratio [aOR] 0.98, 95% confidence interval [CI] 0.98-0.98; P<0.001). The supine position also yielded lower odds of CBD visualization and cannulation (aOR 0.63, 95%CI 0.44-0.91; P=0.011) and higher odds of an incomplete examination (aOR 1.84, 95%CI 1.46-2.30; P<0.001) vs. prone. CONCLUSIONS: The supine position leads to shorter procedures but is more likely to result in poorer visualization and cannulation of the CBD and an incomplete examination. This may reflect the technical difficulty of performing ERCP in the supine position for the endoscopist. Our study supports recommendations for an individualized ERCP approach.

7.
Dig Liver Dis ; 53(10): 1294-1300, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33972190

RESUMO

BACKGROUND: Idiopathic recurrent acute pancreatitis (IRAP) describes frequent episodes of pancreatitis without an etiology found using current testing. We compared the natural history of IRAP with recurrent acute pancreatitis with genetic mutations. METHODS: Retrospective cohort of patients with recurrent acute pancreatitis (≥2 episodes) and negative conventional testing. All patients had ≥1 episode after cholecystectomy and completed genetic testing. Primary outcomes were chronic pancreatitis incidence, pancreatic cancer, and mortality. Secondary outcomes included opioid and ERCP utilization. RESULTS: 128 patients met criteria for presumed IRAP. 35 patients met criteria for true IRAP. 12 patients had recurrent acute pancreatitis with gene mutations. Chronic pancreatitis developed in 27 (77.1%) IRAP patients over a median of 6 years. Chronic pancreatitis incidence was similar in IRAP and CFTR mutation carriers; but developed later in SPINK1 carriers. No patients developed pancreatic cancer or died from pancreatic-related causes. Patients were frequently treated with oral opioids and ERCP, without significant differences within or between groups. CONCLUSION: IRAP and pancreatitis in mutation carriers is associated with chronic pancreatitis. Important differences in natural history were observed, but no association was found with cancer or pancreas-related mortality. Efforts to understand the genetic contributions to IRAP, minimize opioids and unnecessary ERCPs are encouraged.


Assuntos
Progressão da Doença , Pancreatite Crônica/genética , Adulto , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Feminino , Humanos , Masculino , Mutação , Pancreatite Crônica/diagnóstico , Recidiva , Estudos Retrospectivos , Tripsina/genética , Inibidor da Tripsina Pancreática de Kazal/genética
9.
Biomed Pharmacother ; 129: 110432, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32768935

RESUMO

Gastrointestinal diseases are very common problems; available treatments are very limited and come with a range of side effects. Coumarins are an extensive class of phenolic compounds that can be found in plants, fungi and bacteria. The 7-hydroxycoumarin, also known as umbelliferone (UMB), is a compound that comes from coumarin and has been showing biological activities in other studies. As of this scenario, the present study was designed to evaluate the acute oral toxicity, mutagenic, antidiarrheal, anti-bacterial, and antiulcerogenic effects, and antioxidant capacity of UMB. An investigation was conducted through the hippocratic screening method and through histopathological analysis in animals to evaluate the effects of acute oral administration of a dose of 50, 100 and 200 mg/kg of UMB. A micronucleus test on peripheral blood of Swiss mice, which were orally treated with three doses (50, 100 and 200 mg/kg), was conducted to evaluate mutagenic activities. The antiulcerogenic activity was accomplished through the ethanol-induced damage method. Antidiarrheal activities were tested for inducing diarrhea with castor oil and evaluating intestinal transit duration; additionally, the antimicrobial effect against some enteropathogenic bacteria was analyzed. Finally, the antioxidant capability was determined by the capacity of the UMB sample to kidnap the stable radical 2,2-diphenyl-1-picrylhydrazyl. Of the evaluated doses, signs of toxicity after acute administration of the compound were not observed. UMB presented antiulcerogenic activity (100 and 200 mg/kg), which was explained because of its antioxidant capacity. A gastro protective effect was similar to the positive control, and the UMB was able to significantly reduce intestinal transit, and also diarrheal symptoms. Furthermore, UMB had an anti-bacterial effect with minimum inhibitory concentration fluctuating between 62.5 and 1000 µg/mL. Based on these findings, we can suggest that UMB has important biological activities in vivo and in vitro and is not toxic under the evaluated circumstances, which demonstrates its large potential for pharmacological use.


Assuntos
Antiulcerosos/farmacologia , Antidiarreicos/farmacologia , Diarreia/prevenção & controle , Úlcera Gástrica/prevenção & controle , Umbeliferonas/farmacologia , Animais , Antibacterianos/farmacologia , Antiulcerosos/toxicidade , Antidiarreicos/toxicidade , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Óleo de Rícino , Defecação/efeitos dos fármacos , Diarreia/induzido quimicamente , Diarreia/fisiopatologia , Modelos Animais de Doenças , Etanol , Motilidade Gastrointestinal/efeitos dos fármacos , Masculino , Camundongos , Estômago/efeitos dos fármacos , Estômago/patologia , Úlcera Gástrica/induzido quimicamente , Umbeliferonas/toxicidade
10.
Insects ; 11(4)2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32283590

RESUMO

The lychee erinose mite (LEM), Aceria litchii (Keifer) is a serious pest of lychee (Litchi chinensis Sonn.). LEM causes a type of gall called 'erineum' (abnormal felty growth of trichomes from the epidermis), where it feeds, reproduces and protects itself from biotic and abiotic adversities. In February of 2018, LEM was found in a commercial lychee orchard on Pine Island, Florida. Infestations were recorded on young leaves, stems, and inflorescences of approximately 30 young trees (1.5-3.0 yrs.) of three lychee varieties presenting abundant new growth. Although LEM is present in Hawaii, this mite is a prioritized quarantine pest in the continental USA and its territories. Florida LEM specimens showed small morphological differences from the original taxonomic descriptions of Keifer (1943) and Huang (2008). The observed differences are probably an artifact of the drawings in the original descriptions. Molecular comparisons were conducted on the DNA of LEM specimens from India, Hawaii, Brazil, Taiwan, Australia and Florida. The amplified COI fragment showed very low nucleotide variation among the locations and thus, could be used for accurate LEM identification. The ITS1 sequences and partial 5.8S fragments displayed no nucleotide differences for specimens from any of the locations except Australia. Consistent differences were observed in the ITS2 and 28S fragments. The ITS1-ITS2 concatenated phylogeny yielded two lineages, with Australia in one group and Hawaii, India, Brazil, Florida and Taiwan in another. Specimens from Taiwan and Florida present identical ITS and rDNA segments, suggesting a common origin; however, analysis of additional sequences is needed to confirm the origin of the Florida population.

11.
Biomed Pharmacother ; 130: 110609, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34321177

RESUMO

Vulvovaginal candidiasis (VVC) is characterized by inflammatory changes in the vaginal mucosa caused by abnormal colonization of Candida species. Traditional topical therapies using reference antifungal drugs usually present several issues and limitations for VVC treatment. Thus, the interest in new vaginal formulations, mainly those based on compounds from natural origin, has been growing over the last years. Methanolic extract from the plant species Mitracarpus frigidus (Willd. Ex Reem Schult.) K. Schum (MFM) has presented potential antifungal activity against C. albicans vaginal infection. Here, we aimed to develop and characterize a gynecological gel formulation based on chitosan containing MFM and to evaluate its anti-C. albicans effectiveness in the treatment of VVC. First, MFM was incorporated into a gel formulation based on chitosan in three final concentrations: 2.5 %, 5.0 %, and 10.0 %. Next, these gel formulations were subjected to stationary and oscillatory rheological tests. Finally, the gel was tested in an experimental VVC model. The rheological tests indicated pseudoplastic fluids, becoming more viscous and elastic with the increase of the extract concentration, indicating intermolecular interactions. Our in vivo analyses demonstrated a great reduction of vulvovaginal fungal burden and infection accompanied with the reduction of mucosal inflammation after MFM chitosan-gel treatment. The present findings open perspectives for the further use of the MFM-chitosan-gel formulation as a therapeutic alternative for VVC treatment.


Assuntos
Antifúngicos/administração & dosagem , Candidíase Vulvovaginal/tratamento farmacológico , Candidíase Vulvovaginal/microbiologia , Quitosana , Extratos Vegetais/administração & dosagem , Rubiaceae/química , Cremes, Espumas e Géis Vaginais/administração & dosagem , Antifúngicos/química , Fenômenos Químicos , Quitosana/química , Relação Dose-Resposta a Droga , Feminino , Humanos , Extratos Vegetais/química , Cremes, Espumas e Géis Vaginais/química
12.
Rev. iberoam. micol ; 36(4): 192-199, oct.-dic. 2019. ilus, tab, graf
Artigo em Inglês | IBECS | ID: ibc-191415

RESUMO

Background: Candida albicans is the main agent that causes vulvovaginal candidiasis. Resistance among isolates to azole antifungal agents has been reported. Aims: Due to the well-known antifungal potential of curcumin, the purpose of this work was to evaluate the in vitro anticandidal activity of curcumin and its effect in the treatment of experimental vulvovaginal candidiasis. Methods: The anticandidal activity of curcumin was investigated against eight Candida strains by the broth microdilution assay, and its mechanism of action was evaluated by testing the binding to ergosterol. Then, the effect of curcumin in the treatment of vulvovaginal candidiasis was evaluated in an immunosuppressed, estrogen treated rat model. Results: Curcumin showed minimum inhibitory concentration values of 125-1000μg/ml, and the best result was observed against Candida glabrata. The compound was shown to be able to bind to the ergosterol present in the membrane, event that may be the mechanism of action. In addition, in the in vivo model of vulvovaginal candidiasis with C. albicans, treatments reduced the vaginal fungal burden in infected rats after seven days of treatment with different doses. Conclusions: Curcumin could be considered a promising effective antifungal agent in the treatment of vulvovaginal candidiasis


Antecedentes: Candida albicans es la principal causante de la candidiasis vulvovaginal y algunos aislamientos pueden presentar resistencia a los antifúngicos azólicos. Objetivos: Debido al conocido potencial antifúngico de la curcumina, el objetivo de este trabajo fue evaluar su actividad anti-Candidain vitro y su efecto en el tratamiento de la candidiasis vulvovaginal experimental. Métodos: La actividad anti-Candida de la curcumina se evaluó frente a ocho cepas de Candida mediante un ensayo de microdilución en caldo, y su mecanismo de acción se estudió por una prueba de unión a ergosterol. Posteriormente se evaluó el efecto de la curcumina en el tratamiento de la candidiasis vulvovaginal con un modelo de rata inmunosuprimida, tratada con estrógenos. Resultados: La curcumina mostró valores de concentración inhibitoria mínima de 125-1.000μg/ml, y el mejor resultado se observó frente a Candida glabrata. El compuesto demostró ser capaz de unirse al ergosterol de la membrana, lo que podría ser su mecanismo de acción. Además, en el modelo in vivo de candidiasis vulvovaginal con C. albicans, los tratamientos redujeron la carga fúngica vaginal en ratas infectadas después de siete días de tratamiento con diferentes dosis. Conclusiones: La curcumina podría considerarse un agente antifúngico eficaz prometedor en el tratamiento de la candidiasis vulvovaginal


Assuntos
Humanos , Candida albicans/efeitos dos fármacos , Candidíase Vulvovaginal/tratamento farmacológico , Curcumina/farmacocinética , Técnicas In Vitro/métodos , Candida albicans/isolamento & purificação , Farmacorresistência Fúngica , Azóis/farmacocinética , Ergosterol/farmacocinética , Testes de Sensibilidade Microbiana/métodos
13.
Rev Iberoam Micol ; 36(4): 192-199, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31757595

RESUMO

BACKGROUND: Candida albicans is the main agent that causes vulvovaginal candidiasis. Resistance among isolates to azole antifungal agents has been reported. AIMS: Due to the well-known antifungal potential of curcumin, the purpose of this work was to evaluate the in vitro anticandidal activity of curcumin and its effect in the treatment of experimental vulvovaginal candidiasis. METHODS: The anticandidal activity of curcumin was investigated against eight Candida strains by the broth microdilution assay, and its mechanism of action was evaluated by testing the binding to ergosterol. Then, the effect of curcumin in the treatment of vulvovaginal candidiasis was evaluated in an immunosuppressed, estrogen treated rat model. RESULTS: Curcumin showed minimum inhibitory concentration values of 125-1000µg/ml, and the best result was observed against Candida glabrata. The compound was shown to be able to bind to the ergosterol present in the membrane, event that may be the mechanism of action. In addition, in the in vivo model of vulvovaginal candidiasis with C. albicans, treatments reduced the vaginal fungal burden in infected rats after seven days of treatment with different doses. CONCLUSIONS: Curcumin could be considered a promising effective antifungal agent in the treatment of vulvovaginal candidiasis.


Assuntos
Candidíase Vulvovaginal/tratamento farmacológico , Curcumina/uso terapêutico , Animais , Candida/efeitos dos fármacos , Curcumina/farmacologia , Modelos Animais de Doenças , Feminino , Ratos , Ratos Wistar , Resultado do Tratamento
14.
Appl Environ Microbiol ; 85(19)2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31375485

RESUMO

The ambrosia beetle Xyleborus volvulus Fabricius has been reported as a potential vector of the plant pathogen Raffaelea lauricola T.C. Harr., Fraedrich & Aghayeva that is affecting avocado orchards in South Florida. In this study, we examined its life cycle, process of gallery formation, gallery structure, and fungal associates by rearing one generation on avocado sawdust medium under control conditions. The adult foundress excavated a vertical tunnel that constituted the main gallery with a length of 2.5 cm, followed by the construction of up to six secondary galleries with a total length of 4.4 cm. The time period for one generation (egg to adult) was 28 days. Teneral males emerged 3 days after the emergence of the first females. The F1 generation did not significantly contribute to gallery expansion. Four species of Raffaelea and nine yeast species were recovered from galleries and beetles. Raffaelea arxii and Candida berthetii were the most frequent symbionts recovered from new adults and galleries. Candida berthetii dominated during the early stages of the gallery development, whereas R. arxii was most frequent in later stages. Other Raffaelea species were inconsistently isolated from galleries, which suggests a strong association between Xyleborus volvulus and both R. arxii and C. berthetii These results suggest that R. arxii is the primary nutritional symbiont of X. volvulus and that yeast species may be pioneer colonizers that assist with the growth of fungal symbionts.IMPORTANCE Ambrosia beetles cultivate fungi in tunnels bored into weakened host trees. This obligate interaction is required for their survival as beetles feed on these symbiotic fungi, and the fungi benefit from transportation by the beetles. Xyleborus volvulus carries many nonpathogenic symbionts; however, recently the acquisition of Raffaelea lauricola (the causal agent of a lethal vascular disease of lauraceous trees) by this beetle has altered its status from wood degrader to potential pest in avocado. We conducted a study to understand the relationship of this beetle and its fungal associates. Our results show that X. volvulus has a multipartite flexible association with different Raffaelea species. The lack of fidelity in the mutualistic association may explain the acquisition of R. lauricola Knowing the beetle biology and its mutualistic interactions furthers an understanding of the beetle's role as a potential vector and in disease transmission.


Assuntos
Comportamento Animal , Fungos/fisiologia , Simbiose , Gorgulhos/microbiologia , Animais , Vetores de Doenças , Feminino , Florida , Fungos/patogenicidade , Masculino , Persea/microbiologia , Doenças das Plantas/microbiologia , Árvores/microbiologia , Gorgulhos/fisiologia
15.
Life (Basel) ; 8(4)2018 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-30551580

RESUMO

Ambrosia beetles, along with termites and leafcutter ants, are the only fungus-farming lineages within the tree of life. Bacteria harbored by ambrosia beetles may play an essential role in the nutritional symbiotic interactions with their associated fungi; however, little is known about the impact of rearing conditions on the microbiota of ambrosia beetles. We have used culture-independent methods to explore the effect of rearing conditions on the microbiome associated with Xyleborus affinis, Xyleborus bispinatus, and Xyleborus volvulus, evaluating different media in laboratory-controlled conditions and comparing wild and laboratory conditions. Our results revealed that rearing conditions affected the fungal and bacterial microbiome structure and had a strong influence on bacterial metabolic capacities. We propose that the rearing conditions influence the ambrosia-associated fungal and bacterial communities. Furthermore, bacterial microbiome flexibility may help beetles adapt to different substrates.

16.
Insects ; 9(1)2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29495585

RESUMO

Like other members of the tribe Xyleborini, Xyleborus bispinatus Eichhoff can cause economic damage in the Neotropics. X. bispinatus has been found to acquire the laurel wilt pathogen Raffaelea lauricola (T. C. Harr., Fraedrich & Aghayeva) when breeding in a host affected by the pathogen. Its role as a potential vector of R. lauricola is under investigation. The main objective of this study was to evaluate three artificial media, containing sawdust of avocado (Persea americana Mill.) and silkbay (Persea humilis Nash.), for rearing X. bispinatus under laboratory conditions. In addition, the media were inoculated with R. lauricola to evaluate its effect on the biology of X. bispinatus. There was a significant interaction between sawdust species and R. lauricola for all media. Two of the media supported the prolific reproduction of X. bispinatus, but the avocado-based medium was generally more effective than the silkbay-based medium, regardless whether or not it was inoculated with R. lauricola. R. lauricola had a neutral or positive effect on beetle reproduction. The pathogen was frequently recovered from beetle galleries, but only from a few individuals which were reared on inoculated media, and showed limited colonization of the beetle's mycangia. Two media with lower water content were most effective for rearing X. bispinatus.

17.
Environ Entomol ; 46(6): 1275-1283, 2017 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-29029003

RESUMO

Like other ambrosia beetles, Xyleborus volvulus Fabricius (Coleoptera: Curculionidae) lives in a mutualistic symbiotic relationship with fungi that serve as food source. Until recently, X. volvulus was not considered a pest, and none of its symbionts were considered plant pathogens. However, recent reports of an association between X. volvulus and Raffaelea lauricola T.C. Harr., Fraedrich & Aghayeva (Ophiostomatales: Ophiostomataceae), the cause of the laurel wilt disease of avocado (Persea americana Mill. [Laurales: Lauraceae]), and its potential role as vector of the pathogen merit further investigation. The objective of this study was to evaluate three artificial media containing sawdust obtained from avocado or silkbay (Persea humilis Nash) for laboratory rearing of X. volvulus. The effect of R. lauricola in the media on the beetle's reproduction was also evaluated. Of the three media, the one with the lowest content of sawdust and intermediate water content provided the best conditions for rearing X. volvulus. Reproduction on this medium was not affected by the sawdust species or the presence of R. lauricola. On the other two media, there was a significant interaction between sawdust species and R. lauricola. The presence of R. lauricola generally had a negative effect on brood production. There was limited colonization of the mycangia of X. volvulus by R. lauricola on media inoculated with the pathogen. From galleries formed within the best medium, there was 50% recovery of R. lauricola, but recovery was much less from the other two media. Here, we report the best artificial substrate currently known for X. volvulus.


Assuntos
Ophiostomatales/fisiologia , Persea/química , Simbiose , Gorgulhos/crescimento & desenvolvimento , Madeira/química , Animais , Doenças das Plantas/microbiologia , Gorgulhos/microbiologia
18.
Mol Plant Microbe Interact ; 30(11): 896-905, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28800709

RESUMO

MopB is a major outer membrane protein (OMP) in Xylella fastidiosa, a bacterial plant pathogen that causes losses on many economically important crops. Based on in silico analysis, the uncharacterized MopB protein of X. fastidiosa contains a ß-barrel structure with an OmpA-like domain and a predicted calcium-binding motif. Here, MopB function was studied by mutational analysis taking advantage of the natural competence of X. fastidiosa. Mutants of mopB were constructed in two different X. fastidiosa strains, the type strain Temecula and the more virulent WM1-1. Deletion of the mopB gene impaired cell-to-cell aggregation, surface attachment, and biofilm formation in both strains. Interestingly, mopB deletion completely abolished twitching motility. Electron microscopy of the bacterial cell surface revealed that mopB deletion eliminated type IV and type I pili formation, potentially caused by destabilization of the outer membrane. Both mopB mutants showed reduced virulence using tobacco (Nicotiana tabacum) as a host under greenhouse conditions. These results suggest that MopB has pleiotropic functions in biofilm formation and twitching motility and is important for virulence of X. fastidiosa.


Assuntos
Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Proteínas de Membrana/metabolismo , Xylella/fisiologia , Xylella/patogenicidade , Agregação Celular , Contagem de Colônia Microbiana , Simulação por Computador , Técnicas de Inativação de Genes , Movimento , Mutação/genética , Plâncton/crescimento & desenvolvimento , Homologia de Sequência de Aminoácidos , Virulência , Xylella/ultraestrutura
19.
Insects ; 7(4)2016 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-27754408

RESUMO

Members of a complex of cryptic species, that correspond morphologically to the ambrosia beetle Euwallacea fornicatus (Eichhoff) (Coleoptera: Curculionidae: Scolytinae), were recently found attacking avocado (Persea americana Mill.) in Israel and California. In early 2016, an outbreak of another member of this species complex was detected infesting approximately 1500 avocado trees in an avocado orchard at Homestead, Florida. An area-wide survey was conducted in commercial avocado groves of Miami-Dade County, Florida to determine the distribution and abundance of E. nr. fornicatus, to identify different populations of E. nr. fornicatus and their fungal associates, and to assess the extent of damage to avocado trees. Ewallacea nr. fornicatus were captured in 31 of the 33 sampled sites. A sample of 35 beetles from six different locations was identified as E. nr. fornicatus sp. #2, which is genetically distinct from the species causing damage in California and Israel. Eleven fungal associates were identified: an unknown Fusarium sp., AF-8, AF-6, Graphium euwallaceae, Acremonium sp. Acremonium morum, Acremonium masseei, Elaphocordyceps sp. and three yeast species. The unknown Fusarium isolates were the most abundant and frequently found fungus species associated with adult beetles and lesions surrounding the beetle galleries. In addition to fungal associates, three bacteria species were found associated with adult E. nr. fornicatus. Visual inspections detected significant damage in only two orchards. A large number of beetles were captured in locations with no apparent damage on the avocado trees suggesting that E. nr. fornicatus are associated with other host(s) outside the groves or with dead trees or branches inside the groves. More research is needed to determine the potential threat E. nr. fornicatus and its fungal associates pose to the avocado industry and agricultural and natural ecosystems in Florida.

20.
J Public Health Policy ; 37(2): 200-15, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26865319

RESUMO

Despite the introduction of new antifungal agents, the frequency of invasive and mucocutaneous fungal infections as well as resistance to antifungal drugs continues to increase. Over 300 million persons are infected annually with fungi. Resistance to antimicrobials is one of today's major health threats. Can the possible causes of fungal antimicrobial resistance be understood and prevented to minimize risks to public health. We provide an overview of antifungal drug use in European countries, particularly Portugal. We reviewed prescriptions for and over-the-counter sales (OTC) of azoles in Portuguese pharmacies and in alternative shops. We conclude that in Portugal, azole antifungal sales, as well as medical prescribed azoles are very high. The Portuguese population consumes more antifungal drugs per capita than others in Europe.


Assuntos
Antifúngicos/uso terapêutico , Micoses/tratamento farmacológico , Antifúngicos/efeitos adversos , Farmacorresistência Fúngica , Europa (Continente)/epidemiologia , Humanos , Micoses/epidemiologia , Portugal/epidemiologia , Medicamentos sob Prescrição/uso terapêutico
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