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BACKGROUND AND AIMS: Postoperative stricture is a serious common adverse event after extensive endoscopic submucosal dissection (ESD) in the esophagus. Self-assembling peptide (SAP) gel has been shown to promote tissue healing and re-epithelialization. The aim of this study was to evaluate the effect of the SAP gel for esophageal stricture prevention after ESD. METHODS: This was a multicenter prospective study of patients who underwent esophageal ESD followed by SAP gel application between March 2022 and December 2023. Patients were included if the ESD mucosal defect involved ≥50% of the circumference of the esophagus. High-risk cases were defined as mucosal defects ≥75% of the circumference. Stricture was defined as the inability to pass an endoscope ≥8.9 mm in diameter or a narrow-caliber lumen in a patient with symptoms. RESULTS: A total of 43 patients (median age, 71 years; 81.4% male) underwent ESD (median resected specimen size, 50 mm) during the study period. SAP gel (median, 3 mL) was successfully applied in all cases (median time, 4 minutes). In aggregate, stricture occurred in 20.9% (9 of 43) of the cases. Stricture developed in 30.8% of the high-risk cases: 80% (4 of 5) after circumferential ESD and 19% (4 of 21) in those with defects ≥75% but <100% of the circumference. All cases of stricture resolved with endoscopic treatment. Three cases (6.9%) of postoperative bleeding occurred and were adequately managed endoscopically. CONCLUSIONS: We show that SAP gel application was easy, quick, and associated with a relatively low stricture rate comparable to other prophylactic methods. Additional comparative studies are needed to corroborate these preliminary findings.
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Resección Endoscópica de la Mucosa , Neoplasias Esofágicas , Estenosis Esofágica , Geles , Complicaciones Posoperatorias , Humanos , Resección Endoscópica de la Mucosa/efectos adversos , Resección Endoscópica de la Mucosa/métodos , Masculino , Femenino , Estenosis Esofágica/prevención & control , Estenosis Esofágica/etiología , Anciano , Estudios Prospectivos , Persona de Mediana Edad , Neoplasias Esofágicas/cirugía , Complicaciones Posoperatorias/prevención & control , Péptidos/administración & dosificación , Péptidos/uso terapéutico , Anciano de 80 o más Años , Esofagoscopía/métodos , Estados UnidosRESUMEN
BACKGROUND AND AIMS: Variation in architectural traits related to the spatial and angular distribution of leaf area can have considerable impacts on canopy-scale fluxes contributing to water-use efficiency (WUE). These architectural traits are frequent targets for crop improvement and for improving the understanding and predictions of net ecosystem carbon and water fluxes. METHODS: A three-dimensional, leaf-resolving model along with a range of virtually generated hypothetical canopies were used to quantify interactions between canopy structure and WUE by examining its response to variation of leaf inclination independent of leaf azimuth, canopy heterogeneity, vegetation density and physiological parameters. KEY RESULTS: Overall, increasing leaf area index (LAI), increasing the daily-averaged fraction of leaf area projected in the sun direction (Gavg) via the leaf inclination or azimuth distribution and increasing homogeneity had a similar effect on canopy-scale daily fluxes contributing to WUE. Increasing any of these parameters tended to increase daily light interception, increase daily net photosynthesis at low LAI and decrease it at high LAI, increase daily transpiration and decrease WUE. Isolated spherical crowns could decrease photosynthesis by ~60 % but increase daily WUE ≤130 % relative to a homogeneous canopy with equivalent leaf area density. There was no observed optimum in daily canopy WUE as LAI, leaf angle distribution or heterogeneity was varied. However, when the canopy was dense, a more vertical leaf angle distribution could increase both photosynthesis and WUE simultaneously. CONCLUSIONS: Variation in leaf angle and density distributions can have a substantial impact on canopy-level carbon and water fluxes, with potential trade-offs between the two. These traits might therefore be viable target traits for increasing or maintaining crop productivity while using less water, and for improvement of simplified models. Increasing canopy density or decreasing canopy heterogeneity increases the impact of leaf angle on WUE and its dependent processes.
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Fotosíntesis , Hojas de la Planta , Agua , Hojas de la Planta/fisiología , Hojas de la Planta/anatomía & histología , Agua/metabolismo , Agua/fisiología , Fotosíntesis/fisiología , Transpiración de Plantas/fisiología , Modelos Biológicos , Ecosistema , LuzRESUMEN
Microsporum canis is a widely distributed dermatophyte, which is among the main etiological agents of dermatophytosis in humans and domestic animals. This fungus invades, colonizes and nourishes itself on the keratinized tissues of the host through various virulence factors. This review will bring together the known information about the mechanisms, enzymes and their associated genes relevant to the pathogenesis processes of the fungus and will provide an overview of those virulence factors that should be better studied to establish effective methods of prevention and control of the disease. Public databases using the MeSH terms "Microsporum canis", "virulence factors" and each individual virulence factor were reviewed to enlist a series of articles, from where only original works in English and Spanish that included relevant information on the subject were selected. Out of the 147 articles obtained in the review, 46 were selected that reported virulence factors for M. canis in a period between 1988 and 2023. The rest of the articles were discarded because they did not contain information on the topic (67), some were written in different languages (3), and others were repeated in two or more databases (24) or were not original articles (7). The main virulence factors in M. canis are keratinases, fungilisins and subtilisins. However, less commonly reported are biofilms or dipeptidylpeptidases, among others, which have been little researched because they vary in expression or activity between strains and are not considered essential for the infection and survival of the fungus. Although it is known that they are truly involved in resistance, infection and metabolism, we recognize that their study could strengthen the knowledge of the pathogenesis of M. canis with the aim of achieving effective treatments, as well as the prevention and control of infection.
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Microsporum , Factores de Virulencia , Microsporum/patogenicidad , Microsporum/genética , Factores de Virulencia/genética , Factores de Virulencia/metabolismo , Animales , Humanos , Fenotipo , Dermatomicosis/microbiología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismoRESUMEN
Optimism seems to foster the ability to manage adverse situations better-a finding especially relevant for disadvantaged populations. Employing a unique sample from a small underprivileged village, we studied the association between religious/spiritual practices and dispositional optimism. The village belongs to a developing country that is, by far, the most secular country in Latin America; this makes it particularly interesting for exploring the role of religious/spiritual practices in this context. We found that these practices were positively associated with higher optimism, measured by the Life Orientation Test-Revised (LOT-R): those who practice spirituality, score, on average, 14.4 percentage points higher on the LOT-R than those who did not. This association seems to be especially robust in the case of the poor and less educated: those with religious/spiritual practices score 20 percentage points higher on the LOT-R. Thus, the role that these practices may play in dispositional optimism in disadvantaged populations deserves more attention.
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Personalidad , Poblaciones Vulnerables , Humanos , Optimismo , Espiritualidad , UruguayRESUMEN
Cross-validation is a useful strategy to address problems associated with the post hoc model fitting. The aim of this study was to cross-validate the BAS-2, in two samples (Calibration and Validation Samples), using an invariance testing strategy. 1127 Mexican adolescents (508 males and 619 females), aged 11-19 years (M = 15.41, SD = 2.30), allocated in two samples (n1 = 672; n2 = 455) completed the Mexican version of the BAS-2, along with other body image-related instruments. The cross-validation supported the generalizability of the one-factor respecified model of the BAS-2. The measure was invariant across body mass index and age, but not across sex. Internal consistency and test-retest reliability (a three-week period between each test) was excellent. In support of the validity of the BAS-2, it was positively associated with scores on body esteem, but negatively with body mass index, drive for thinness, and body dissatisfaction. Normal-weight and young adolescents groups showed higher body appreciation than excess-weight and late adolescents groups, respectively. Considering these findings, it is reasonable to conclude that the BAS-2 is a reliable and valid instrument to assess body appreciation in Mexican adolescents. LEVEL OF EVIDENCE: Level V, cross-sectional, descriptive study.
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Imagen Corporal , Adolescente , Índice de Masa Corporal , Estudios Transversales , Análisis Factorial , Femenino , Humanos , Masculino , México , Psicometría , Reproducibilidad de los Resultados , Encuestas y CuestionariosRESUMEN
BACKGROUND: The most common aetiological agents of mucormycosis are Rhizopus, Mucor, Apophysomyces and Lichtheimia. Apophysomyces is comparatively rare, as it has been reported in less than 3% of mucormycosis cases. The genus Apophysomyces includes six species, and only A. elegans, A. mexicanus, A. variabilis and A. ossiformis have been reported to cause infections in both immunocompetent and immunocompromised patients. CASE PRESENTATION: We present a case of a 46-year-old male patient with bilateral blepharoedema, corneal opacity in the left eye and poorly controlled diabetes mellitus. The patient was subjected to total maxillectomy, exenteration of the left orbit and treatment with liposomal amphotericin B. Direct mycological analysis with KOH 10% revealed hyaline, coenocytic, long and wide hyphae. Apophysomyces ossiformis was identified from maxillary biopsy using 18S-ITS1-5.8S-ITS2-28S rRNA gene amplification and sequencing. The patient requested to be transferred to another hospital to continue treatment, where he died on the ninth day after admittance. CONCLUSION: To the best of our knowledge, this is the first case of rhino-orbital mucormycosis due to A. ossiformis with a fatal outcome. This case reveals the need to identify the fungus causing mucormycosis with molecular methods to identify adequate treatment therapies for patients with this infection.
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Complicaciones de la Diabetes/microbiología , Mucorales/genética , Mucormicosis/complicaciones , Enfermedades Orbitales/complicaciones , Rinitis/complicaciones , Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Biopsia , Complicaciones de la Diabetes/tratamiento farmacológico , Complicaciones de la Diabetes/cirugía , Resultado Fatal , Humanos , Huésped Inmunocomprometido , Masculino , Maxilar/microbiología , Maxilar/patología , Maxilar/cirugía , Persona de Mediana Edad , Mucormicosis/tratamiento farmacológico , Mucormicosis/microbiología , Mucormicosis/cirugía , Enfermedades Orbitales/tratamiento farmacológico , Enfermedades Orbitales/microbiología , Enfermedades Orbitales/cirugía , ARN Ribosómico 28S/genética , Rinitis/tratamiento farmacológico , Rinitis/microbiología , Rinitis/cirugíaRESUMEN
Background: The Trichophyton mentagrophytes complex is the second most common causal agent of dermatophytosis. It comprises five species-T. mentagrophytes, T. interdigitale, T. erinacei, T quinckeanum, and T. benhamie, as well as nine different genotypes of T. mentagrophytes / T. interdigitale-which are morphologically similar; however, their susceptibility to antifungal agents may differ. For targeted therapy and better prognosis, it is important to identify these species at a molecular level. However, since many hospitals lack molecular methods, the actual aetiology of dermatophytosis caused by this complex remains unknown. Objective: To characterize 55 anthropophilic isolates of the T. mentagrophytes complex recovered from a dermatological centre in Yucatán, Mexico. Material and methods: Fifty-five isolates of the T. mentagrophytes complex were obtained from patients with tinea capitis, tinea pedis, tinea corporis, tinea barbae, and tinea unguium. They were characterized by their colonial and microscopic morphology on Sabouraud dextrose agar (SDA) and through the sequencing of a fragment from the region ITS1-5.8S-ITS2. Results: All colonies grown on SDA were white. Forty-six isolates formed colonies with a powdery texture, while nine isolates formed colonies with a velvety texture. The micromorphological features were typical of the T. mentagrophytes complex. The molecular analysis revealed that 55 isolates were microorganisms that belonged to the T. mentagrophytes complex, that 46 formed powdery colonies representing T. mentagrophytes, and that the other nine isolates that formed velvety colonies represented T. interdigitale. The latter nine isolates were obtained from patients with tinea pedis, tinea corporis, and tinea unguium. Conclusions: The colony morphology on SDA led to the identification of 46 isolates as T. mentagrophytes and nine isolates as T. interdigitale. At a molecular level, the species identified by their morphology were identified only as T. mentagrophytes complex.
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Antifúngicos/farmacología , ADN Intergénico/genética , Tiña/genética , Trichophyton/genética , Dermatosis Facial/genética , Dermatosis Facial/microbiología , Genotipo , Humanos , Onicomicosis/genética , Onicomicosis/microbiología , Análisis de Secuencia de ADN , Tiña/microbiología , Tiña/patología , Tiña del Cuero Cabelludo/genética , Tiña del Cuero Cabelludo/microbiología , Tiña del Pie/genética , Tiña del Pie/microbiología , Trichophyton/clasificación , Trichophyton/efectos de los fármacos , Trichophyton/patogenicidadRESUMEN
Antigenic fractions of 100, 50, 37, and 28 kDa obtained through the SDS-PAGE method that were more frequently recognized by anti-Coccidioides antibodies in the sera of coccidioidomycosis patients were selected using western blotting. Subsequently, these bands were sequenced, and the obtained proteins were analysed by BLAST to choose peptides specific for Coccidioides spp. from among the shared aligned sequences of related fungi. A peptide specific for C. immitis was selected from the "GPI anchored serine-threonine rich protein OS C. immitis", while from the "uncharacterized protein of C. immitis", we selected a peptide for C. immitis and C. posadasii. These proteins arose from the 100 kDa antigenic fraction. From the protein "fatty acid amide hydrolase 1 of C. posadasii" that was identified from the 50 kDa antigenic fraction, a peptide was selected that recognized C. immitis and C. posadasii. In addition, the analysis of all the peptides (353) of each of the assembled proteins showed that only 35 had 100% identity with proteins of C. immitis and C. posadasii, one had 100% identity with only C. immitis, and one had 100% identity with only C. posadasii. These peptides can be used as diagnostic reagents, vaccines, and antifungals.
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Antígenos Fúngicos/aislamiento & purificación , Western Blotting/métodos , Coccidioides/inmunología , Coccidioidomicosis/sangre , Coccidioidomicosis/inmunología , Electroforesis en Gel de Poliacrilamida/métodos , Péptidos/aislamiento & purificación , Adulto , Anciano , Secuencia de Aminoácidos , Antígenos Fúngicos/química , Niño , Coccidioides/aislamiento & purificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Péptidos/química , Adulto JovenRESUMEN
PURPOSE: The purpose of this study was to determine whether the muscle appearance satisfaction scale (MASS) shows acceptable psychometric properties in Mexican bodybuilders. METHODS: A total of 258 Mexican male bodybuilders were recruited. Two self-report questionnaires, including the MASS and drive for muscularity scale (DMS), were administered. Six models of the latent structure of the MASS were evaluated, using confirmatory factor analysis with maximum likelihood, considering robust Satorra-Bentler correction to estimate the fit of the models to the data. RESULTS: Similar to the original MASS, the series of CFA confirmed that the Mexican version was well represented with the 17-item five-factor structure, which showed a good model fit [Satorra-Bentler Chi-square (109, n = 258) = 189.18, p < 0.0001; NNFI = 0.91; CFI = 0.93; IFI = 0.93; RMSEA = 0.05 (0.04, 0.07)]. Internal consistency was estimated with McDonald's omega, which was acceptable for the MASS (0.88), and their subscales (0.80 to 0.89), except for muscle checking scale (0.77). Test-retest reliability analysis showed stability of the MASS total as well as of the subscale scores over a 2-week period (intraclass correlation coefficients = 0.75-0.91). Construct validity was demonstrated by a significant positive correlation between MASS and DMS results (r = 0.75; p = 0.0001). These results were similar to those of previous studies, which demonstrate the scale's usefulness. CONCLUSIONS: Our results support the suitability of the MASS and its subscales to measure muscle dysmorphia symptoms in Mexican male bodybuilders.
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Composición Corporal/fisiología , Imagen Corporal , Satisfacción Personal , Adolescente , Adulto , Humanos , Masculino , México , Persona de Mediana Edad , Músculo Esquelético , Psicometría , Reproducibilidad de los Resultados , Adulto JovenAsunto(s)
Enfermedad de Parkinson , Femenino , Humanos , Encuestas y Cuestionarios , Salud de la MujerRESUMEN
OBJECTIVES: Epigenetic alterations have been implicated in the development of platinum resistance in ovarian cancer (OC). In this study, we aimed to identify DNA methylation changes in platinum resistant tumors and their functional implications. METHODS: To identify DNA methylation alterations we used the Illumina 450k DNA methylation array and profiled platinum sensitive and resistant OC xenografts. Validation analyses employed RT-PCR and immunohistochemistry (IHC). RESULTS: Genome-wide DNA methylation analysis of OC xenografts identified 6 genes (SSH3, SLC12A4, TMEM88, PCDHGC3, DAXX, MEST) whose promoters were significantly hypomethylated in resistant compared to sensitive (control) xenografts (p<0.001). We confirmed that TMEM88 and DAXX mRNA expression levels were increased in platinum resistant compared to control xenografts, inversely correlated with promoter methylation levels. Furthermore treatment of OC cells with SGI-110 (guadecitabine), a DNA methyl transferase (DNMT) inhibitor, increased TMEM88 mRNA expression levels, supporting that TMEM88 is transcriptionally regulated by promoter methylation. TMEM88 was detectable by IHC in all histological types of ovarian tumors and its knock-down by using siRNA promoted OC cell proliferation and colony formation and re-sensitized cells to platinum. Furthermore, TMEM88 knock down induced upregulation of cyclin D1 and c-Myc, known Wnt target genes, supporting that TMEM88 inhibits Wnt signaling. CONCLUSIONS: Overall, our results support that OC platinum resistance was correlated with TMEM88 overexpression regulated through decreased promoter methylation. Our data suggest that TMEM88 functions as an inhibitor of Wnt signaling, contributing to the development of platinum resistance.
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Metilación de ADN , Proteínas de la Membrana/genética , Neoplasias Glandulares y Epiteliales/tratamiento farmacológico , Neoplasias Glandulares y Epiteliales/genética , Compuestos Organoplatinos/farmacología , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Animales , Carcinoma Epitelial de Ovario , Línea Celular Tumoral , Proliferación Celular/genética , Resistencia a Antineoplásicos , Femenino , Técnicas de Silenciamiento del Gen , Humanos , Proteínas de la Membrana/biosíntesis , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias Glandulares y Epiteliales/metabolismo , Neoplasias Glandulares y Epiteliales/patología , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Regiones Promotoras Genéticas , Vía de Señalización Wnt , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND: Coccidioidomycosis, a potentially fatal fungal infection, is considered an emergent mycotic disease because of the increased incidence of fungal infections registered over recent years. Infection occurs through the inhalation of arthroconidia from two main species of Coccidioides: Coccidioides immitis and C. posadasii, which are both endemic to arid and semi-arid regions of North America. Coccidioides species not only infect humans but can also infect other mammals (land, aquatic, wild or domestic), reptiles and birds. OBJECTIVE: To obtain information regarding the habitat of Coccidioides spp. and the animals infected by this fungus and to identify the role that infected animals play as reservoirs and disseminators of this fungus in nature. MATERIALS: A literature review was conducted to identify the habitat of Coccidioides spp. and the infected non-human animal species targeted by this fungus. RESULTS AND CONCLUSIONS: This review allows us to suggest that Coccidioides spp. may be classified as halotolerant organisms; nevertheless, to perpetuate their life cycle, these organisms depend on different animal species (reservoirs) that serve as a link with the environment, by acting as disseminators of the fungi in nature.
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Coccidioides/fisiología , Coccidioidomicosis/transmisión , Reservorios de Enfermedades , Vectores de Enfermedades , Ecosistema , Animales , Coccidioidomicosis/microbiología , Humanos , América del NorteRESUMEN
OBJECTIVE: To evaluate a new device for obtaining endometrial biopsies which combines global endometrial disruption using a brush with a built-in suction process. STUDY DESIGN: Endometrial biopsies were collected, using the GDP-Tao device, from fresh uteri hysterectomy specimens after completion of surgery. Results were compared to final hysterectomy pathology. Specificity and sensitivity and positive and negative predictive values were calculated. RESULTS: Based on a sample size calculation, 42 patients were included in this study. Endometrial tissue adequate for diagnosis was obtained in 93% (39/42) of biopsies. Classifying atypia as a positive result, the sensitivity of the new device was 96% (23/24), with specificity of 87% (13/15). The positive predictive value was 92% (23/25) and the negative predictive value, 93% (13/14). There were 2 nondiagnostic (ND) samples from GDP-Tao with final pathology of benign endometrium. One specimen was ND on both GDP-Tao and final pathology due to absence of tissue after prior endometrial ablation. When stratified by uterine size, benign or malignant, the results were similar. CONCLUSION: Our validation study showed encouraging results for the GDP-Tao, which combines tissue disruption and aspiration into a single process. The device provides a reliable means of obtaining adequate samples to accurately detect endometrial cancer with a high negative and positive predictive value.
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Atención Ambulatoria , Biopsia/métodos , Hiperplasia Endometrial/patología , Neoplasias Endometriales/patología , Endometrio/patología , Adulto , Anciano , Anciano de 80 o más Años , Biopsia/instrumentación , Femenino , Humanos , Histerectomía , Persona de Mediana Edad , Tamaño de los Órganos , Estudios Prospectivos , Sensibilidad y EspecificidadRESUMEN
Hydrocephalus develops in up to 80-90% of children with myelomeningocele (MM) after closure of the defect. Traditionally, ventriculoperitoneal shunts have been used to manage hydrocephalus in these patients. A role for endoscopic third ventriculostomy (ETV) in MM has provoked much debate, principally due to anatomical variants described, which may complicate the procedure. We present 7 cases of children with MM and hydrocephalus undergoing a total of 10 ETV procedures. All patients demonstrated clinical improvement (in acute/subacute cases) or stabilization (in chronic cases). Three patients requiring a second ETV have shown clinical stability and renewed radiological evidence of functioning ventriculostomies in follow-up since reintervention. ETV can be used, albeit cautiously, in selected cases of hydrocephalus associated with MM. However, the frequency with which anatomical variation is encountered and the difficulty of the assessment of success make the procedure more challenging than usual.
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Meningomielocele/cirugía , Neuroendoscopía/métodos , Tercer Ventrículo/cirugía , Ventriculostomía/métodos , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Meningomielocele/diagnóstico , Estudios Retrospectivos , Tercer Ventrículo/patologíaRESUMEN
In this study, molecular typing using Randomly Amplified Polymorphic DNA (RAPD-PCR) was conducted on 16 original isolates of Metarhizium acridum obtained from locusts (Schistocerca piceifrons ssp. piceifrons.) in Mexico (MX). The analysis included reference strains of the genus Metarhizium sourced from various geographical regions. The isolates were identified by phenotypic (macro and micromorphology) and genotypic methods (RAPD-PCR and Amplified Fragment Length Polymorphisms (AFLP), through a multidimensional analysis of principal coordinates (PCoA) and a minimum spanning network (MST). Subsequently, Sequences-Characterized Amplified Region (SCAR) markers were developed for the molecular detection of M. acridum, these markers were chosen from polymorphic patterns obtained with 14 primers via RAPD-PCR. Phenotypic and genotypic characterization identified the MX isolates as M. acridum. Of all the polymorphic patterns obtained, only OPA04 and OPA05 were chosen, which presented species-specific bands for M. acridum, and further utilized to create SCAR markers through cloning and sequencing of the specific bands. The specificity of these two markers was confirmed via Southern hybridization. The SCAR markers (Ma-160OPA-05 and Ma-151OPA-04) exhibit remarkable sensitivity, detecting down to less than 0.1 ng, as well as high specificity, as evidenced by their inability to cross-amplify or generate amplification with DNAs from other strains of Metarhizium (as Metarhizium anisopliae) or different genera of entomopathogenic fungi (Cordyceps fumosorosea and Akanthomyces lecanii). These SCAR markers yield readily detectable results, showcasing high reproducibility. They serve as a valuable tool, especially in field applications.
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We evaluated the specificity of the primers OPF-01, P54, and 1253 to identify A. fumigatus, A. flavus, and A. niger, respectively, with the RAPD-PCR method. Eighty-two isolates belonging to the sections Fumigati, Flavi, and Nigri were used. The isolates were identified by phenotypic (macro- and micromorphology) and genotypic (partial sequences of the BenA gene) methods. The RAPD-PCR method was used to obtain polymorphic patterns with the primers OPF-01, P54, and 1253. The specificity of the polymorphic patterns of the isolates of each species was evaluated through the UPGMA clustering method and logistic regression model. All isolates of the genus Aspergillus were identified at the section level by macro- and micromorphology showing the typical morphology of the sections Fumigati, Flavi, and Nigri, and the species were identified by the construction of the phylogeny of the partial sequence of the BenA gene. The patterns' polymorphic strains obtained with the primers OPF-01, P54, and 1253 for the isolates of A. fumigatus, A. flavus, and A niger, respectively, showed the same polymorphic pattern as the reference strains for each species. To verify the specificity of the primers, they were tested with other species from the sections Fumigati, Flavi and Nigri. The results support that the primers OPF-01, P54, and 1253 generate polymorphic patterns by RAPD-PCR species specific to A. fumigatus, A. flavus, and A. niger, respectively.
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BACKGROUND: Coccidioides immitis and C. posadasii cause coccidioidomycosis, a disease that is endemic to North and South America, but for Central America, the incidence of coccidioidomycosis has not been clearly established. Several studies suggest genetic variability in these fungi; however, little definitive information has been discovered about the variability of Coccidioides fungi in Mexico (MX) and Argentina (AR). Thus, the goals for this work were to study 32 Coccidioides spp. isolates from MX and AR, identify the species of these Coccidioides spp. isolates, analyse their phenotypic variability, examine their genetic variability and investigate the Coccidioides reproductive system and its level of genetic differentiation. METHODS: Coccidioides spp. isolates from MX and AR were taxonomically identified by phylogenetic inference analysis using partial sequences of the Ag2/PRA gene and their phenotypic characteristics analysed. The genetic variability, reproductive system and level of differentiation were estimated using AFLP markers. The level of genetic variability was assessed measuring the percentage of polymorphic loci, number of effective allele, expected heterocygosity and Index of Association (IA). The degree of genetic differentiation was determined by AMOVA. Genetic similarities among isolates were estimated using Jaccard index. The UPGMA was used to contsruct the corresponding dendrogram. Finally, a network of haplotypes was built to evaluate the genealogical relationships among AFLP haplotypes. RESULTS: All isolates of Coccidioides spp. from MX and AR were identified as C. posadasii. No phenotypic variability was observed among the C. posadasii isolates from MX and AR. Analyses of genetic diversity and population structure were conducted using AFLP markers. Different estimators of genetic variability indicated that the C. posadasii isolates from MX and AR had high genetic variability. Furthermore, AMOVA, dendrogram and haplotype network showed a small genetic differentiation among the C. posadasii populations analysed from MX and AR. Additionally, the IA calculated for the isolates suggested that the species has a recombinant reproductive system. CONCLUSIONS: No phenotypic variability was observed among the C. posadasii isolates from MX and AR. The high genetic variability observed in the isolates from MX and AR and the small genetic differentiation observed among the C. posadasii isolates analysed, suggest that this species could be distributed as a single genetic population in Latin America.
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Coccidioides/genética , Coccidioides/aislamiento & purificación , Coccidioidomicosis/microbiología , Variación Genética , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Argentina , Coccidioides/clasificación , Coccidioides/crecimiento & desarrollo , Humanos , México , Datos de Secuencia Molecular , FilogeniaRESUMEN
Rate constants of reactions of hydroxyl radical with cyclopentane (k1), cyclohexane (k2), cycloheptane (k3), and cyclooctane (k4) have been acquired at 240-340 K and a total pressure of about 1 Torr using the technique of relative rate combined with discharge flow and mass spectrometry (RR/DF/MS). At 298 K, the rate constants are determined using two reference compounds, which are averaged to be k1 = (4.81 ± 0.88) × 10(-12), k2 = (6.41 ± 0.85) × 10(-12), k3 = (10.30 ± 1.44) × 10(-12), and k4 = (1.42 ± 0.27) × 10(-11) cm(3) molecule(-1) s(-1). The Arrhenius expressions at 240-340 K for these reactions are determined to be k1(T) = (2.43 ± 0.50) × 10(-11)exp[-(481 ± 58)/T], k2(T) = (3.96 ± 0.60) × 10(-11)exp[-554 ± 42)/T], k3(T) = (5.74 ± 0.66) × 10(-11)exp[-527 ± 33)/T], and k4(T) = (1.12 ± 0.21) × 10(-10)exp[-626 ± 53)/T]. Using the kcycloalkane+OH(277 K) values measured in the present work, the atmospheric lifetime for cyclopentane, cyclohexane, cycloheptane, and cyclooctane is estimated to be about 78, 64, 38, and 29 h, respectively.
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BACKGROUND: Infections are a major cause of morbidity and mortality in patients with pemphigus vulgaris (PV). One of the most common infections in these patients is candidiasis. This is probably due to the use of systemic immunosuppressants, including oral and intravenous corticosteroids, mainly in megadoses (pulse therapy), although it is unknown if there are other associated factors, in addition to immunosuppressive treatment. We determine the factors associated with candidiasis in PV patients in two second-care level hospitals in Mexico. METHODS: We reviewed 100 cases with PV. Cases were randomly selected from the databases of two second-care level hospitals between January 2010 and December 2019 (10 years). The primary endpoint was the incidence of candidiasis in patients with PV. RESULTS: One hundred patients with PV were enrolled in this retrospective study. Candidiasis was observed in 79 patients (79%). A maximum corticosteroid dose of 55 mg/day during the last year (p = 0.001) and a higher neutrophil/lymphocyte ratio were associated with candidiasis in patients with PV (p = 0.001). CONCLUSION: Risk factors favoring candidiasis in patients with PV are not only related to the use of corticosteroids, but also to demographic factors, the activity of the disease, and the systemic inflammation associated with autoimmunity.