RESUMO
Treatment-resistant dermatophytosis caused by the members of the Trichophyton mentagrophytes/Trichophyton interdigitale species group (TMTISG) is increasing worldwide. We aimed to determine the prevalence of TMTISG in patients with dermatophytosis in two centers from north of Iran and detect the possible mutations in the squalene epoxidase (SQLE) gene in relevant terbinafine (TRB) resistant pathogenic isolates. From November 2021 to December 2022, 1960 patients suspected to dermatophytosis and referred to two mycology referral laboratories in the north of Iran were included in the study. Identification of all dermatophyte isolates was confirmed by RFLP of rDNA internal transcribed spacer (ITS) regions. Antifungal susceptibility testing against five common antifungals using the CLSI-M38-A3 protocol was performed. The TMTISG isolates resistant to TRB, were further analyzed to determine the possible mutations in the SQLE gene. Totally, 647 cases (33%) were positive for dermatophytosis of which 280 cases (43.3%) were identified as members of TMTISG. These were more frequently isolated from tinea corporis 131 (44.56%) and tinea cruris 116 (39.46%). Of 280 TMTISG isolates, 40 (14.3%) were resistant to TRB (MIC ≥ 4 µg/mL), all found to be T. indotineae in ITS sequencing. In SQLE sequencing 34 (85%) of TRB-resistant isolates had coincident mutations of Phe397Leu and Ala448Thr whereas four and two isolates had single mutations of Phe397Leu and Leu393Ser, respectively. Overall, the resistance of Iranian TMTISG isolates to TRB greatly occurred by a mutation of Phe397Leu in the SQLE gene as alone or in combination with Ala448Thr. Nevertheless, for the occurrence of in vitro resistance, only the presence of Phe397Leu mutation seems to be decisive.
Assuntos
Antifúngicos , Arthrodermataceae , Farmacorresistência Fúngica , Testes de Sensibilidade Microbiana , Esqualeno Mono-Oxigenase , Terbinafina , Tinha , Irã (Geográfico)/epidemiologia , Farmacorresistência Fúngica/genética , Humanos , Antifúngicos/farmacologia , Terbinafina/farmacologia , Estudos Transversais , Tinha/microbiologia , Tinha/epidemiologia , Prevalência , Arthrodermataceae/genética , Arthrodermataceae/efeitos dos fármacos , Masculino , Feminino , Esqualeno Mono-Oxigenase/genética , Adulto , Pessoa de Meia-Idade , Mutação , Idoso , Adulto Jovem , Adolescente , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , CriançaRESUMO
BACKGROUND: The data on the epidemiological and antifungal susceptibility profile of tinea capitis (TC) in Iran has not been updated in recent decades. This report presents the Iranian epidemiological and drug susceptibility data regarding the distribution of dermatophytes species isolated by six national mycology centers for a period of one year (2020-2021). MATERIAL AND METHODS: A total of 2100 clinical samples from individuals suspeted to TC were subjected to mycological analysis of direct microscopy and culture. For definite species identification, the culture isolates were additionally subjected to PCR-RFLP and PCR-sequencing of the ITS ribosomal DNA (ITS-rDNA) region. Antifungal susceptibility profiles for eight common antifungal drugs were determined by CLSI M38-A3 guidelines. The SQLE gene was partially amplified and sequenced in two terbinafine-resistant and two susceptible T. mentagrophytes isolates to elucidate probable substitutions involved in resistance. RESULTS: TC (n = 94) was diagnosed in 75 children (79.8%) and 19 adults (20.2%) by direct microscopy and culture. Frequency of TC was significantly more among males (66 males = 70.2% vs 28 females = 29.8%). The prevalent age group affected was 5-9 years (39.36%). Thirty-two (34.04%) T. mentagrophytes, 27 (28.7%) T. tonsurans, 14 (14.9%) M. canis, 13 (13.8%) T. violaceum, 5 (5.32%) T. indotineae, 2 (2.1%) T. benhamiae, and 1 (1.1%) T. schoenleinii were identified as the causative agents. MIC values of isolates showed susceptibility to all antifungal agents, except for fluconazole and griseofulvin with GM MIC of 11.91 µg/ml and 2.01 µg/ml, respectively. Terbinafine exhibited more activity against isolates, with GM MIC 0.084 µg/ml followed by ketoconazole (0.100 µg/ml), econazole (0.107 µg/ml), itraconazole (0.133 µg/ml), butenafine (0.142 µg/ml), and miconazole (0.325 µg/ml). Two resistant T. mentagrophytes isolates harbored missense mutations in SQLE gene, corresponding to amino acid substitution F397L. Remarkably, one unique mutation, C1255T, in the SQLE sequence of two terbinafine-susceptible T. mentagrophytes strains leading to a change of leucine at the 419th position to phenylalanine (L419F) was detected. CONCLUSIONS: T. mentagrophytes, T. tonsurans, and M. canis remained the main agents of TC in Iran, however less known species such as T. indotinea and T. benhamiae are emerging as new ones. Terbinafine could still be the appropriate choice for the treatment of diverse forms of TC.
Assuntos
Arthrodermataceae , Tinha do Couro Cabeludo , Tinha , Masculino , Criança , Adulto , Feminino , Humanos , Pré-Escolar , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Terbinafina/farmacologia , Terbinafina/uso terapêutico , Irã (Geográfico)/epidemiologia , Tinha/microbiologia , Testes de Sensibilidade Microbiana , Tinha do Couro Cabeludo/epidemiologia , Tinha do Couro Cabeludo/tratamento farmacológico , Mutação , Trichophyton , Farmacorresistência Fúngica/genéticaRESUMO
BACKGROUND: Efinaconazole is non-lacquer-based with a low surface tension that efficiently targets delivery of active ingredient into the nail and nail bed. OBJECTIVES: To develop an optimal, stable formulation of efinaconazole topical solution 10% (ETS10). METHODS: We evaluated the safety and efficacy of ETS10 on 10 Iranian participants in a pilot, single-group and before-after clinical study, for up to 8 weeks in onychomycosis. RESULTS: The study showed reasonable results concerning the short period of treatment. During the period of storage, the formulation showed no variation in colour, odour and pH. The average pH at initial, 1st, 6th and 12th months was 4.65, 4.64, 4.65 and 4.64, respectively. The assay of an active pharmaceutical ingredient in the formulation was desired over the whole period. This indicates that antimicrobial activity has been adequate and efficient. A significant decrease in Investigator Global Assessment (IGA) of the target toenails was also defined as the efficacy endpoint. The median score for IGA at baseline visit was 3 out of 5 which decreased to 2 out of 5 and the decrease was statistically significant. CONCLUSION: The study clarifies the new efficacy of ETS10 in subjects with onychomycosis and passed the safety study successfully. These properties may develop the potentiality of ETS10 as a good treatment option for patients with onychomycosis.
Assuntos
Antifúngicos/uso terapêutico , Doenças da Unha/tratamento farmacológico , Unhas/microbiologia , Onicomicose/tratamento farmacológico , Triazóis/uso terapêutico , Administração Tópica , Adolescente , Adulto , Idoso , Antifúngicos/administração & dosagem , Feminino , Pé , Humanos , Masculino , Pessoa de Meia-Idade , Doenças da Unha/microbiologia , Onicomicose/microbiologia , Projetos Piloto , Triazóis/administração & dosagem , Adulto JovemRESUMO
Context: In Persian medicine, topical ingredients such as Rosa damascena Mill. (Rosaceae), are usually recommended for the treatment of uterine diseases. Scientific evaluation of these historical documents can be valuable for finding new potential use in conventional medicine.Objective: This clinical trial was performed to determine whether the use of the 'ward' vaginal tablet, which contains Rosa damascena, Punica granatum L. (Punicaceae), Querqus infectoria Oliv. (Fagaceae), Myrtus communis L. (Myrtaceae) and Nardostachys jatamansi (D.Don) DC. (Caprifoliaceae) could alleviate the symptoms of vulvovaginal candidiasis.Materials and methods: A parallel double-blinded placebo-controlled study was done. Eighteen to fifty-year-old women with vulvovaginal candidiasis were divided into the 'ward' and placebo groups, 46 individuals in each group. The 'ward' group received the 'ward' vaginal tablet containing 200 mg of dried extract. Placebo group received a placebo (composed of corn starch and lactose). One tablet was applied through the vagina for 7 consecutive nights.Results: Two weeks after medication administration, the vaginal discharge sample of patients was re-cultured; 29 patients (63.045%) in the 'ward' group and 6 (13.04%) patients in the placebo group had negative culture (p < 0.001). All clinical symptoms including itching, irritation, and vaginal discharge were significantly reduced in the 'ward' group compared with the placebo group following the intervention and the follow up (p < 0.05).Discussion and conclusions: The findings suggest the 'ward' vaginal tablet could ameliorate vulvovaginal candidiasis. Future larger studies are recommended due to compare the therapeutic effect of the 'ward' vaginal tablet with common treatments.
Assuntos
Antifúngicos/administração & dosagem , Candidíase Vulvovaginal/tratamento farmacológico , Medicina Tradicional/métodos , Extratos Vegetais/administração & dosagem , Adolescente , Adulto , Antifúngicos/isolamento & purificação , Candidíase Vulvovaginal/diagnóstico , Candidíase Vulvovaginal/epidemiologia , Método Duplo-Cego , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Pessoa de Meia-Idade , Pérsia , Extratos Vegetais/isolamento & purificação , Preparações de Plantas/administração & dosagem , Preparações de Plantas/isolamento & purificação , Resultado do Tratamento , Vagina/efeitos dos fármacos , Vagina/microbiologia , Cremes, Espumas e Géis Vaginais/administração & dosagem , Cremes, Espumas e Géis Vaginais/isolamento & purificação , Adulto JovemRESUMO
Following our previous report on evaluation of the beta tubulin real-time PCR for detection of dermatophytosis, this study aimed to compare the real-time PCR assay with conventional methods for the clinical assessment of its diagnostic performance. Samples from a total of 853 patients with suspected dermatophyte lesions were subjected to direct examination (all samples), culture (499 samples) and real-time PCR (all samples). Fungal DNA was extracted directly from clinical samples using a conical steel bullet, followed by purification with a commercial kit and subjected to the Taq-Man probe-based real-time PCR. The study showed that among the 499 specimens for which all three methods were used, 156 (31.2%), 128 (25.6%) and 205 (41.0%) were found to be positive by direct microscopy, culture and real-time PCR respectively. Real-time PCR significantly increased the detection rate of dermatophytes compared with microscopy (288 vs 229) with 87% concordance between the two methods. The sensitivity, specificity, positive predictive value, and negative predictive value of the real-time PCR was 87.5%, 85%, 66.5% and 95.2% respectively. Although real-time PCR performed better on skin than on nail samples, it should not yet fully replace conventional diagnosis.
Assuntos
Fungos/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Tinha/diagnóstico , Tubulina (Proteína)/genética , DNA Fúngico/genética , Dermatomicoses , Feminino , Fungos/genética , Humanos , Masculino , Microsporum/genética , Microsporum/isolamento & purificação , Técnicas de Tipagem Micológica/métodos , Unhas/microbiologia , Sensibilidade e Especificidade , Pele/microbiologia , Tinha/microbiologia , Trichophyton/genética , Trichophyton/isolamento & purificaçãoRESUMO
Onychomycosis is a common fungal infection of nails which is mainly caused by dermatophyte species and less often by yeasts and non-dermatophyte molds. We present a case of onychomycosis due to Aspergillus clavatus for the first time worldwide. The patient was an immunocompetent 32-year-old woman who identified with Psoriasis of the nail. The presence of A. clavatus in a nail sample was confirmed using microscopic and culture analysis followed by PCR of the ß-tubulin gene. After antifungal susceptibility test, it is revealed that the isolate was resistant to the majority of common antifungal drugs, but finally the patient was treated with itraconazole 200 mg daily. A. clavatus and drug-resistant A. clavatus have not previously been reported from onychomycosis.
Assuntos
Antifúngicos/uso terapêutico , Aspergillus/efeitos dos fármacos , Farmacorresistência Fúngica Múltipla , Dermatoses da Mão/tratamento farmacológico , Itraconazol/uso terapêutico , Onicomicose/tratamento farmacológico , Adulto , Aspergillus/isolamento & purificação , Sequência de Bases , Feminino , Dermatoses da Mão/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Onicomicose/microbiologia , Análise de Sequência de DNA , Tubulina (Proteína)/genéticaRESUMO
Background and Objectives: The presence of fungi in the respiratory tract as mycobiome, particularly Candida species (spp.), remains a serious problem due to increasing numbers of immunocompromised patients. The confirmed reliable existence of these pathogens due to frequent colonization is essential. This investigation aimed to recognize Candida spp. among isolates from bronchoalveolar lavage of immunocompromised and critically ill patients and to evaluate their susceptibility to antimycotic drugs. Materials and Methods: Bronchoalveolar lavage fluid was collected from 161 hospitalized patients presenting with suspected respiratory fungal infection /colonization. The specimens were examined by standard molecular and mycological assays. Candida spp. were recognized with sequence assessment of the D1-D2 section of the large subunit ribosomal DNA. The susceptibility of Candida isolates to common antimycotic drugs was distinguished by standard broth microdilution. Results: Seventy-one clinical isolates of Candida spp. were recognized. Candida albicans was the most frequent, followed by C. glabrata, C. krusei (Pichia kudriavzevii), C. dubliniensis, C. parapsilosis, and C. tropicalis. We found 5.1% of C. albicans isolates and 8% of C. glabrata isolates to show resistance to fluconazole. The whole of the Candida spp. were sensitive to amphotericin B and caspofungin. Conclusion: This study demonstrated that C. albicans and C. glabrata are the most common isolates of bronchoalveolar lavage fluid in patients, and the drug susceptibility screening confirmed that amphotericin B and caspofungin are effective against Candida spp. but some C. glabrata and C. albicans isolates showed resistance to fluconazole.
RESUMO
In this research, molecular dynamics (MD) simulation is used to investigate the efficiency of carbon nanotubes (CNT) and boron nitride nanotubes (BNNT) in removing lead ions from contaminated waters. Then the effect of functionalizing nanotubes with -COO- and COOH- functional groups and the nanotubes' absorption performance of two different concentrations of lead ions are studied. To better evaluate adsorption process, the set of descriptors, such as interaction energies, radial distribution function, etc., are calculated. The MD results show that the absorption performance is significantly improved by modifying the surface of CNT and BNNT with functional groups. In addition, the adsorption capacity increases in higher concentrations of Pb ions at BNNTCOO- and CNTCOOH systems. The interaction energy of BNNTCOO- with a concentration of 50 lead ions is - 2879.28 kJ/mol, which is about 106 kJ/mol more negative than BNNTCOO- at a concentration of 20 lead ions. Also, it is observed that the functionalization of both nanotubes with -COO- increases their absorption capacity. The obtained results from this study provide significant information about the mechanisms of lead adsorption on the surface of nanotubes.
Assuntos
Metais Pesados , Nanotubos de Carbono , Íons , Água , AdsorçãoRESUMO
Background and Purpose: Species identification of Malassezia using culture-dependent methods is time-consuming due to their fastidious growth requirements. This study aimed to evaluate a rapid and accurate molecular method in order to diagnose the pityriasis versicolor (PV) and identify Malassezia species from direct clinical samples. Materials and Methods: Skin scraping or tape samples from patients with PV and healthy volunteers as the control group were collected. Diagnosis of PV was confirmed by direct microscopic examination. The DNA extraction was performed according to the steel-bullet beating method. Polymerase chain reaction-restriction fragment length polymorphism assay using HhaI restriction enzyme was applied for the identification and differentiation of Malassezia species. Results: The PCR method was able to detect Malassezia in 92.1% of specimens which were also confirmed with microscopic examination. Statistically, a significant association was observed between the results of the two assays (P < 0.001). Moderate agreement was identified between the two methods to diagnose the PV in both populations (Kappa: 0.55). Considering microscopic examination as the gold standard method for confirmation of PV, the sensitivity, specificity, positive predictive value, and negative predictive value values of the PCR assay for recognition of PV were 85%, 75%, 92%, and 60%, respectively. M. globosa and M. restricta were the most prevalent species isolated from patients. Conclusion: In this study, the two-step molecular method based on the amplification of the D1/D2 domain and digestion of the PCR product by one restriction enzyme was able to diagnose and identify Malassezia directly from clinical samples. Consequently, it can be said that the molecular-based method provides more facilities to identify fastidious species, such as M. restricta.
RESUMO
Background and Purpose: Vulvovaginal candidiasis (VVC) is considered the most common mucosal infection caused by Candida species. Azoles were considered the first-line treatment for VVC or recurrent vulvovaginal candidiasis (RVVC) in both healthy and immunocompromised populations. Recently, azole-resistant isolates, especially among non-albicans Candida samples have been encountered. This study aimed to evaluate the antifungal susceptibility profile of Candida spp. isolated from VVC or RVVC patients and assess the molecular resistance mechanism of Candida spp. to azole and echinocandin. Materials and Methods: Point mutation analysis was performed on the ERG11 and FKS candidate genes of azole- and caspofungin-resistant Candida albicans and Candida glabrata isolates. Real-time polymerase chain reaction was performed to gain insight into the differential expression of ERG11 mRNA. Results: Variations in the amino acid D116E were observed in fluconazole- and itraconazole-resistant C. albicans strains, and changes in amino acid E517Q were observed only in fluconazole-resistant C. albicans strains. No polymorphisms were observed in the complete sequence alignment of the ERG11 gene in one azole-resistant C. glabrata isolate. The mutation triggered the changes in the amino acid serine in the reference gene FKS1 by the leucine at position 642 (S642L) of the isolates. Conclusion: In patients with persistent or recurrent infection, the choice of an antifungal agent is often challenging and requires monitoring of the antifungal susceptibility of the colonizing strain. C. albicans and C. glabrata isolates can be resistant to azole and caspofungin antifungal agents without mutations in the ERG 11 and HS1 regions of the FKS1 gene.
RESUMO
Background and Objectives: Onychomycosis is caused by dermatophyte species, non-dermatophyte moulds (NDMs), and accounts for roughly 50% of all nail diseases. As the prevalence of onychomycosis is increasing, new epidemiologic documents may help with treatment and prevention. The present investigation aims to determine the epidemiological profile of onychomycosis in 2 mycology laboratories. Materials and Methods: A cross-sectional study conducted during eight months (2019-2020) on 169 patients with positive nail mycology tests referred to two mycological laboratory centers affiliated with Tehran University of Medical Science. The nail clippings were examined by direct smear and culture. Also, molecular assays were performed if needed. Results: 10% of nail lesions referred to Razi Hospital (RH), and 30% of nail lesions referred to TUMS mycology laboratory were positive. Middle age (40-60) suffer more from onychomycosis. Aspergillus flavus, Trichophyton mentagrophytes, and Candida albicans were the most common etiologic agents in each of the three main classes of fungi causing onychomycosis. Females were more infected. NDMs were the predominant etiologic agents, and toenails were the most common site of onychomycosis. Conclusion: The pattern of etiologic agents and clinical signs of onychomycosis differs according to geographical region and age, so repeated epidemiological surveys of onychomycosis seem to be fundamental.
RESUMO
Background: The resistance to treatment of onychomycosis is increasingly reported. The present study aimed to assess the antifungal activity of itraconazole, terbinafine, luliconazole, and efinaconazole against dermatophytes, molds, and also yeast isolated from patients with onychomycosis. Furthermore, the mechanism of resistance to terbinafine in resistant Trichophyton mentagrophytes species was evaluated using the squalene epoxidase (SQLE) gene sequence. Methods: A total of 71 fungal isolates were collected from 97 patients with suspected onychomycosis. The identification of fungal species was performed using conventional and molecular approaches. In vitro drug susceptibility for itraconazole, terbinafine, luliconazole, and efinaconazole was carried out using the broth microdilution method according to the CLSI-M60 and CLSI-M38 3rd ed., respectively. The SQLE gene of one terbinafine-resistant T. mentagrophytes was amplified using the specific primers. Results: Efinaconazole and luliconazole demonstrated higher effectiveness against all isolates in the study. One mismatch was detected at position 1177, which showed A â C change associated with Phe397Leu amino acid substitution of the SQLE protein in terbinafine-resistant T. mentagrophytes. Conclusion: The occurrence of resistant strains of organisms causing onychomycosis should be considered and evaluated. Furthermore, the identification of amino acid changes responsible for resistance to antifungals is a useful consideration in drug-target interaction.
Assuntos
Antifúngicos/farmacologia , Farmacorresistência Fúngica/genética , Onicomicose/microbiologia , Genes Fúngicos , Humanos , Testes de Sensibilidade MicrobianaRESUMO
In this study, a new pyrimidine-based chemosensor (PyrCS) has been developed for sequential detection of copper (II) and cyanide ions. The PyrCS has revealed high sensitivity and selectivity toward copper ion over other metal ions in aqueous media. The PyrCS as an optical probe exhibited a distinct color change and a bathochromic shift in UV spectra in the presence of copper ion in a few seconds due to the formation of stable complex (PyrCS-Cu2+). The results confirmed that the PyrCS has a widely linear detection range of 0.3-30⯵M toward Cu2+. The calculated limit of detection for Cu2+ ions was low as 0.116⯵M. Moreover, the fluorescent intensity of PyrCS at 507â¯nm was significantly quenched in the presence of Cu2⺠and Fe2⺠ions. Additionally, complex PyrCS-Cu2+ was successfully used to detect cyanide ions via Cu2+ displacement approach. The free PyrCS was recovered after adding the CNâ¾ ions in a few seconds due to the formation of the stable copper cyanide complex Cu(CN)x. The calculated LOD for CNâ¾ ions was low as 0.320⯵M. The data also clarified that the other competing anions did not create a clear color change in solutions. Since the proposed method could provide a vivid colorimetric response in the presence of detected analytes within the pH range of 3-9, we can claim that the developed chemosensor can be utilized in any physical and biological conditions.
RESUMO
In this study, a new thiazolylazopyrimidine-functionalized TiO2 nanosensor (TiO2-TAP) has been developed for sensitive and selective colorimetric detection of Cu2+ in water samples. Thiazolylazopyrimidine (TAP) as an azo ligand and TiO2-TAP as highly selective nanosensor were successfully prepared through the diazo coupling reaction and surface chemical modification, respectively. Characterization of TiO2-TAP NPs using Fourier transmission infrared (FT-IR), field emission scanning electron microscopy (FESEM), energy dispersive X- ray spectroscopy (EDX), and X-ray diffraction (XRD) analysis revealed that the TiO2 NPs were effectively modified with the synthesized epoxy-activated thiazolylazopyrimidine. The synthesized azo ligand containing azo chromophore (N=N) produce color and make a stable complex formation with Cu2+ based on charge-transfer transduction in the detection system. The color change of TiO2-TAP solution from yellow to red occur directly after few seconds of addition of Cu2+ ions, as a result of surface complexation. The TiO2-TAP has revealed high affinity, sensitivity and selectivity for copper ion over other competing metal ions in aqueous media. The experimental data revealed that the Cu2+ ions was sensed and adsorbed by the TiO2-TAP at optimal pH 5.0. The results also confirmed that the TiO2-TAP has a wide linear detection range for Cu2+ (0.01 to 12.5 µM). From UV-vis titration experiment, the limit of detection (LOD) for Cu2+ ions was found to be 2.51 nM. The proposed method was successfully applied for the sensitive and selective detection of Cu2+ in tap water, sea water and well water. In addition, Cu2+ recovery improved using the TiO2-TAP containing N, S and O atoms as chelating sites. Therefore, the developed nanosensor with great features like the cost-effective, excellent sensitively and selectively, short response times and high adsorption efficiency for Cu2+ can be utilized in any physical and biological conditions.
Assuntos
Colorimetria , Nanopartículas , Espectroscopia de Infravermelho com Transformada de Fourier , Titânio , ÁguaRESUMO
Accurate and automatic registration of multimodal retinal images such as fluorescein angiography (FA) and optical coherence tomography (OCT) enables utilization of supplementary information. FA is a gold standard imaging modality that depicts neurovascular structure of retina and is used for diagnosing neurovascular-related diseases such as diabetic retinopathy (DR). Unlike FA, OCT is non-invasive retinal imaging modality that provides cross-sectional data of retina. Due to differences in contrast, resolution and brightness of multimodal retinal images, the images resulted from vessel extraction of image pairs are not exactly the same. Also, prevalent feature detection, extraction and matching schemes do not result in perfect matches. In addition, the relationships between retinal image pairs are usually modeled by affine transformation, which cannot generate accurate alignments due to the non-planar retina surface. In this paper, a precise registration scheme is proposed to align FA and OCT images via scanning laser ophthalmoscopy (SLO) photographs as intermediate images. For this purpose, first a retinal vessel segmentation is applied to extract main blood vessels from the FA and SLO images. Next, a novel global registration is proposed based on the Gaussian model for curved surface of retina. For doing so, first a global rigid transformation is applied to FA vessel-map image using a new feature-based method to align it with SLO vessel-map photograph, in a way that outlier matched features resulted from not-perfect vessel segmentation are completely eliminated. After that, the transformed image is globally registered again considering Gaussian model for curved surface of retina to improve the precision of the previous step. Eventually a local non-rigid transformation is exploited to register two images perfectly. The experimental results indicate the presented scheme is more precise compared to other registration methods.
RESUMO
INTRODUCTION: The aim of this study was to evaluate some virulence factors in Candida albicans isolates from patients with onychomycosis and determine the correlation between these factors and the antifungal resistance profile. METHODS: Seventy species of C. albicans were confirmed using polymerase chain reaction amplification of the HWP1 gene. According to the Clinical & Laboratory Standards Institute guidelines, the susceptibility profile of four antifungal agents was investigated, and the production of aspartyl protease, phospholipase, haemolysin, and biofilm was determined. The correlation between these profiles was also investigated. RESULTS: The isolates indicated different levels of resistance and production of virulence factors. Significant correlations were observed between the minimum inhibitory concentration (MIC) of fluconazole/itraconazole and biofilm production, between phospholipase production and fluconazole/itraconazole MIC, and between fluconazole MIC and hemolytic activity in C. albicans isolates. The results also showed significant correlations between phospholipase activity and biofilm production. CONCLUSIONS: Our findings will contribute to a better understanding of the pathogenesis of C. albicans and characterize the relationship between virulence factors and antifungal resistance, which may suggest new therapeutic strategies considering the possible involvement of the virulence mechanism in the effectiveness of treatment.
Assuntos
Antifúngicos/farmacologia , Candida albicans/patogenicidade , Unhas/microbiologia , Onicomicose/microbiologia , Fatores de Virulência , Ácido Aspártico Proteases/biossíntese , Biofilmes/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida albicans/ultraestrutura , Farmacorresistência Fúngica , Hemólise , Humanos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Fosfolipases/biossíntese , Reação em Cadeia da PolimeraseRESUMO
Yeasts are common etiologic agents of onychomycosis. This study reported a case of onychomycosis due to Cryptococcus friedmannii (Naganishia friedmannii). This yeast was isolated of the right great toenail of 57-year-old man. Microscopic examination of nail scrapings showed budding cells with thin capsule. Sequence analyzes of the internal transcribed spacer regions was closely related to Cryptococcus friedmannii. The results of susceptibility testing showed the Cryptococcus friedmannii to be sensitive to fluconazole, itraconazole and amphotericin B.
RESUMO
BACKGROUND: Non-dermatophyte onychomycosis (NDO) is caused by a wide range of mold fungi other than dermatophytes, and has been reported at various rates in different countries worldwide. Studies on the incidence of NDO in the community are essential for understanding its epidemiology and control, as well as for the appropriate treatment of these infections. OBJECTIVES: In this study, the incidence of NDO in Tehran, Iran, was compared to the incidence of onychomycoses due to dermatophytes and yeasts. METHODS: From 2014 through 2015, samples from a total of 1,069 patients with suspected fungal nail diseases, who were referred to three medical mycology laboratories in Tehran, were collected and subjected to direct examination (all samples) and culture (788 samples). Differentiation of the causative agents of onychomycosis was based on microscopic observation of characteristic fungal elements in the nail samples and growth of a significant number of identical colonies on the culture plate. RESULTS: Based on only direct microscopy, onychomycosis was diagnosed in 424 (39.6%) cases, among which 35.8% were caused by dermatophytes, 32.7% by yeasts, and 29.3% by non-dermatophyte molds (NDMs), while 2.2% were mixed infections. Direct exam was significantly more sensitive than culture for the diagnosis. The most commonly isolated NDMs were Aspergillus spp. (69.3%, n = 52), followed by Fusarium spp. (n = 7). The other isolated species were Paecilomyces spp., Scopulariopsis spp., Acremonium spp., Cladosporium spp., and Chrysosporium spp., with only one case of each. CONCLUSIONS: An increasing frequency of NDO compared to onychomycosis due to other causative agents has been noticeable over the past few years in Iran. This epidemiological data may be useful in the development of preventive and educational strategies.
RESUMO
Abstract INTRODUCTION: The aim of this study was to evaluate some virulence factors in Candida albicans isolates from patients with onychomycosis and determine the correlation between these factors and the antifungal resistance profile. METHODS: Seventy species of C. albicans were confirmed using polymerase chain reaction amplification of the HWP1 gene. According to the Clinical & Laboratory Standards Institute guidelines, the susceptibility profile of four antifungal agents was investigated, and the production of aspartyl protease, phospholipase, haemolysin, and biofilm was determined. The correlation between these profiles was also investigated. RESULTS: The isolates indicated different levels of resistance and production of virulence factors. Significant correlations were observed between the minimum inhibitory concentration (MIC) of fluconazole/itraconazole and biofilm production, between phospholipase production and fluconazole/itraconazole MIC, and between fluconazole MIC and hemolytic activity in C. albicans isolates. The results also showed significant correlations between phospholipase activity and biofilm production. CONCLUSIONS: Our findings will contribute to a better understanding of the pathogenesis of C. albicans and characterize the relationship between virulence factors and antifungal resistance, which may suggest new therapeutic strategies considering the possible involvement of the virulence mechanism in the effectiveness of treatment.