Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 58
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Med Mycol ; 60(2)2022 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35022770

RESUMEN

We reviewed the performance of a panfungal ITS-2 PCR and Sanger sequencing assay performed on 88 FFPE specimens at The Hospital for Sick Children (Toronto, Canada) in 2019. A potential fungal pathogen was identified by ITS PCR in 62.7 and 2.9% of positive and negative direct slide examination of tissue specimens, respectively. ITS amplicons were detected in 87/88 specimens, with 53/88 (60.2%) considered as 'positive-contaminants' and 34/88 (38.6%) as 'positive-potential pathogen' upon sequencing. Potential pathogens included Blastomyces dermatitidis (17.1%), Cryptococcus neoformans (17.1%), Histoplasma capsulatum (14.3%) and Mucormycetes (11.4%). Laboratories should only perform ITS PCR on FFPE tissues if fungal elements have been confirmed on histopathology slides. LAY SUMMARY: In this study, we examined how well a DNA-based test could detect DNA from fungi in archived human biopsy tissues. The best performance was achieved if fungi were seen in the tissue under a microscope before being tested. Our results indicate that we should only use this test if these conditions are met.


Asunto(s)
Formaldehído , Histoplasma , Animales , ADN de Hongos/genética , Histoplasma/genética , Adhesión en Parafina/veterinaria , Reacción en Cadena de la Polimerasa/veterinaria , Sensibilidad y Especificidad
2.
J Digit Imaging ; 35(4): 817-833, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35962150

RESUMEN

Despite technological advances in the analysis of digital images for medical consultations, many health information systems lack the ability to correlate textual descriptions of image findings linked to the actual images. Images and reports often reside in separate silos in the medical record throughout the process of image viewing, report authoring, and report consumption. Forward-thinking centers and early adopters have created interactive reports with multimedia elements and embedded hyperlinks in reports that connect the narrative text with the related source images and measurements. Most of these solutions rely on proprietary single-vendor systems for viewing and reporting in the absence of any encompassing industry standards to facilitate interoperability with the electronic health record (EHR) and other systems. International standards have enabled the digitization of image acquisition, storage, viewing, and structured reporting. These provide the foundation to discuss enhanced reporting. Lessons learned in the digital transformation of radiology and pathology can serve as a basis for interactive multimedia reporting (IMR) across image-centric medical specialties. This paper describes the standard-based infrastructure and communications to fulfill recently defined clinical requirements through a consensus from an international workgroup of multidisciplinary medical specialists, informaticists, and industry participants. These efforts have led toward the development of an Integrating the Healthcare Enterprise (IHE) profile that will serve as a foundation for interoperable interactive multimedia reporting.


Asunto(s)
Medicina , Sistemas de Información Radiológica , Comunicación , Diagnóstico por Imagen , Registros Electrónicos de Salud , Humanos , Multimedia
3.
Clin Infect Dis ; 73(9): e2521-e2528, 2021 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-32544950

RESUMEN

BACKGROUND: We previously identified Pseudomonas aeruginosa isolates with characteristics typical of chronic infection in some early infections in children with cystic fibrosis (CF), suggesting that these isolates may have been acquired from other patients. Our objective was to define the extent of P. aeruginosa strain-sharing in early CF infections and its impact on antibiotic eradication treatment failure rates. METHODS: We performed whole genome sequencing on isolates from early pediatric CF pulmonary infections and from the following comparator groups in the same hospital: chronic CF infection, sink drains, sterile site infections, and asymptomatic carriage. Univariate logistic regression was used to assess factors associated with treatment failure. RESULTS: In this retrospective, observational study, 1029 isolates were sequenced. The CF clones strain B and clone C were present. In 70 CF patients with early infections, 14 shared strains infected 29 (41%) patients over 5 years; 16% (n = 14) of infections had mixed strains. In the 70 children, approximately one-third of shared-strain infections were likely due to patient-to-patient transmission. Mixed-strain infections were associated with strain-sharing (odds ratio, 8.50; 95% confidence interval, 2.2-33.4; P = .002). Strain-sharing was not associated with antibiotic eradication treatment failure; however, nosocomial strain transmission was associated with establishment of chronic infection in a CF sibling pair. CONCLUSIONS: Although early P. aeruginosa CF infection is thought to reflect acquisition of diverse strains from community reservoirs, we identified frequent early CF strain-sharing that was associated with the presence of mixed strains and instances of possible patient-to-patient transmission.


Asunto(s)
Fibrosis Quística , Infecciones por Pseudomonas , Antibacterianos/uso terapéutico , Niño , Fibrosis Quística/complicaciones , Fibrosis Quística/tratamiento farmacológico , Humanos , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/epidemiología , Pseudomonas aeruginosa/genética , Estudios Retrospectivos
4.
J Digit Imaging ; 34(3): 495-522, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34131793

RESUMEN

Diagnostic and evidential static image, video clip, and sound multimedia are captured during routine clinical care in cardiology, dermatology, ophthalmology, pathology, physiatry, radiation oncology, radiology, endoscopic procedural specialties, and other medical disciplines. Providers typically describe the multimedia findings in contemporaneous electronic health record clinical notes or associate a textual interpretative report. Visual communication aids commonly used to connect, synthesize, and supplement multimedia and descriptive text outside medicine remain technically challenging to integrate into patient care. Such beneficial interactive elements may include hyperlinks between text, multimedia elements, alphanumeric and geometric annotations, tables, graphs, timelines, diagrams, anatomic maps, and hyperlinks to external educational references that patients or provider consumers may find valuable. This HIMSS-SIIM Enterprise Imaging Community workgroup white paper outlines the current and desired clinical future state of interactive multimedia reporting (IMR). The workgroup adopted a consensus definition of IMR as "interactive medical documentation that combines clinical images, videos, sound, imaging metadata, and/or image annotations with text, typographic emphases, tables, graphs, event timelines, anatomic maps, hyperlinks, and/or educational resources to optimize communication between medical professionals, and between medical professionals and their patients." This white paper also serves as a precursor for future efforts toward solving technical issues impeding routine interactive multimedia report creation and ingestion into electronic health records.


Asunto(s)
Sistemas de Información Radiológica , Radiología , Consenso , Diagnóstico por Imagen , Humanos , Multimedia
5.
PLoS Pathog ; 14(12): e1007453, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30532201

RESUMEN

Cystic fibrosis (CF) lung infections caused by members of the Burkholderia cepacia complex, such as Burkholderia multivorans, are associated with high rates of mortality and morbidity. We performed a population genomics study of 111 B. multivorans sputum isolates from one CF patient through three stages of infection including an early incident isolate, deep sampling of a one-year period of chronic infection occurring weeks before a lung transplant, and deep sampling of a post-transplant infection. We reconstructed the evolutionary history of the population and used a lineage-controlled genome-wide association study (GWAS) approach to identify genetic variants associated with antibiotic resistance. We found the incident isolate was basally related to the rest of the strains and more susceptible to antibiotics from three classes (ß-lactams, aminoglycosides, quinolones). The chronic infection isolates diversified into multiple, distinct genetic lineages and showed reduced antimicrobial susceptibility to the same antibiotics. The post-transplant reinfection isolates derived from the same source as the incident isolate and were genetically distinct from the chronic isolates. They also had a level of susceptibility in between that of the incident and chronic isolates. We identified numerous examples of potential parallel pathoadaptation, in which multiple mutations were found in the same locus or even codon. The set of parallel pathoadaptive loci was enriched for functions associated with virulence and resistance. Our GWAS analysis identified statistical associations between a polymorphism in the ampD locus with resistance to ß-lactams, and polymorphisms in an araC transcriptional regulator and an outer membrane porin with resistance to both aminoglycosides and quinolones. Additionally, these three loci were independently mutated four, three and two times, respectively, providing further support for parallel pathoadaptation. Finally, we identified a minimum of 14 recombination events, and observed that loci carrying putative parallel pathoadaptations and polymorphisms statistically associated with ß-lactam resistance were over-represented in these recombinogenic regions.


Asunto(s)
Infecciones por Burkholderia/genética , Complejo Burkholderia cepacia/genética , Farmacorresistencia Bacteriana/genética , Evolución Molecular , Genes Bacterianos/genética , Variación Genética/efectos de los fármacos , Estudio de Asociación del Genoma Completo , Humanos , Recombinación Genética
6.
Gen Dent ; 68(3): 51-56, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32348244

RESUMEN

Low-viscosity polymer resins, or surface sealants (SSs), have been utilized as a means of finalizing the polishing step following the placement of composite resin restorations. The aim of this study was to measure the surface roughness (Ra) of composite resins treated with different SSs before and after exposure to an accelerated artificial aging protocol. The study included 5 experimental groups of composite resin discs (TPH Spectra ST) treated with different SSs (PermaSeal, Embrace WetBond Seal-n-Shine, OptiGuard, BisCover LV, and DuraFinish) and a control group consisting of untreated discs (n = 6 per group). The discs were prepared by inserting composite resin in 10 × 1-mm rings, covering the ring and material with a transparent strip, compressing the assembly between glass slides, and polymerizing through the slides on each side for 40 seconds with an LED curing light. Each disc except for the control specimens received a coating of the selected SS followed by application of a transparent matrix strip and then light polymerization for 20 seconds using an LED light source. Surface roughness measurements were obtained with a digital contact profilometer at baseline (immediately after polymerization) and following exposure to a thermocycling regimen to simulate aging. The data were analyzed using 2-way analysis of variance and post hoc Student-Newman-Keuls test with significance set at P < 0.05. There were no statistically significant differences among the groups at baseline. There were no statistically significant differences between the baseline and post-thermocycling Ra measurements except among the DuraFinish specimens, which were significantly rougher than all other groups after accelerated artificial aging. The use of SSs for the initial insertion and possibly for the long-term maintenance of composite resins could be minimally beneficial for restoration maintenance if a transparent covering medium is utilized during polymerization. However, due to the effects caused by formation of an oxygen-inhibited layer of unpolymerized monomers if a covering medium is not used, the results suggest the benefits do not offset the costs considering both gloss and Ra surface-testing parameters.


Asunto(s)
Resinas Compuestas , Pulido Dental , Humanos , Ensayo de Materiales , Propiedades de Superficie
7.
PLoS Pathog ; 11(11): e1005308, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26588216

RESUMEN

The microbiome shapes diverse facets of human biology and disease, with the importance of fungi only beginning to be appreciated. Microbial communities infiltrate diverse anatomical sites as with the respiratory tract of healthy humans and those with diseases such as cystic fibrosis, where chronic colonization and infection lead to clinical decline. Although fungi are frequently recovered from cystic fibrosis patient sputum samples and have been associated with deterioration of lung function, understanding of species and population dynamics remains in its infancy. Here, we coupled high-throughput sequencing of the ribosomal RNA internal transcribed spacer 1 (ITS1) with phenotypic and genotypic analyses of fungi from 89 sputum samples from 28 cystic fibrosis patients. Fungal communities defined by sequencing were concordant with those defined by culture-based analyses of 1,603 isolates from the same samples. Different patients harbored distinct fungal communities. There were detectable trends, however, including colonization with Candida and Aspergillus species, which was not perturbed by clinical exacerbation or treatment. We identified considerable inter- and intra-species phenotypic variation in traits important for host adaptation, including antifungal drug resistance and morphogenesis. While variation in drug resistance was largely between species, striking variation in morphogenesis emerged within Candida species. Filamentation was uncoupled from inducing cues in 28 Candida isolates recovered from six patients. The filamentous isolates were resistant to the filamentation-repressive effects of Pseudomonas aeruginosa, implicating inter-kingdom interactions as the selective force. Genome sequencing revealed that all but one of the filamentous isolates harbored mutations in the transcriptional repressor NRG1; such mutations were necessary and sufficient for the filamentous phenotype. Six independent nrg1 mutations arose in Candida isolates from different patients, providing a poignant example of parallel evolution. Together, this combined clinical-genomic approach provides a high-resolution portrait of the fungal microbiome of cystic fibrosis patient lungs and identifies a genetic basis of pathogen adaptation.


Asunto(s)
Fibrosis Quística/genética , Hongos/genética , Microbiota , Neurregulina-1/metabolismo , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa , Esputo/microbiología , Adaptación Biológica , Farmacorresistencia Fúngica/genética , Humanos , Microbiota/fisiología , Mutación/genética , Neurregulina-1/genética , Pseudomonas aeruginosa/genética
8.
Regul Toxicol Pharmacol ; 73(1): 27-42, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26111605

RESUMEN

This comparative study was conducted to assess background physiologic and pharmacologic parameters of cynomolgus macaques (Macaca fascicularis) from Cambodia, from a mixed Asian source (Cambodia, Vietnam and Indonesia), and from Mauritius. This evaluation provides a comprehensive assessment of several of these parameters in a single study. Ten male and 10 female captive-bred, age-matched macaques from each source were evaluated. Criteria for evaluation included weight gain, assessment of drug metabolizing enzyme activity, metabolomic analysis, immunologic assessments (lymphocyte subsets, TDAR, and serum Ig isotyping), clinical pathology evaluations, physical (respiratory, neurologic, cardiovascular, and ophthalmologic) examinations, pathogen screening, organ weights, and gross and microscopic pathology analyses. The results of this evaluation indicate that, compared to macaques of Asian origin, macaques from Mauritius had the lowest incidence and/or severity of spontaneous pathologic findings in several organs and tissues (lymphoid organs, stomach, kidney, urothelium, heart, arteries and lung) and better testicular maturity at a given age with minimal variability in organ weights. Although slight differences were observed in other parameters, none were considered detrimental to the use of macaques of Asian or Mauritius origin in pharmaceutical candidate safety studies with the use of a consistent source, concomitant controls, and appropriate background knowledge and screening.


Asunto(s)
Macaca fascicularis/fisiología , Tamaño de los Órganos/fisiología , Animales , Pueblo Asiatico , Femenino , Humanos , Masculino , Mauricio
9.
Proc Natl Acad Sci U S A ; 109(31): 12811-6, 2012 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-22802619

RESUMEN

Δ(9)-Tetrahydrocannabinol (THC) and other cannabinoids are responsible for the psychoactive and medicinal properties of Cannabis sativa L. (marijuana). The first intermediate in the cannabinoid biosynthetic pathway is proposed to be olivetolic acid (OA), an alkylresorcinolic acid that forms the polyketide nucleus of the cannabinoids. OA has been postulated to be synthesized by a type III polyketide synthase (PKS) enzyme, but so far type III PKSs from cannabis have been shown to produce catalytic byproducts instead of OA. We analyzed the transcriptome of glandular trichomes from female cannabis flowers, which are the primary site of cannabinoid biosynthesis, and searched for polyketide cyclase-like enzymes that could assist in OA cyclization. Here, we show that a type III PKS (tetraketide synthase) from cannabis trichomes requires the presence of a polyketide cyclase enzyme, olivetolic acid cyclase (OAC), which catalyzes a C2-C7 intramolecular aldol condensation with carboxylate retention to form OA. OAC is a dimeric α+ß barrel (DABB) protein that is structurally similar to polyketide cyclases from Streptomyces species. OAC transcript is present at high levels in glandular trichomes, an expression profile that parallels other cannabinoid pathway enzymes. Our identification of OAC both clarifies the cannabinoid pathway and demonstrates unexpected evolutionary parallels between polyketide biosynthesis in plants and bacteria. In addition, the widespread occurrence of DABB proteins in plants suggests that polyketide cyclases may play an overlooked role in generating plant chemical diversity.


Asunto(s)
Cannabis/enzimología , Regulación Enzimológica de la Expresión Génica/fisiología , Regulación de la Expresión Génica de las Plantas/fisiología , Transferasas Intramoleculares/metabolismo , Proteínas de Plantas/metabolismo , Policétidos/metabolismo , Salicilatos/metabolismo , Secuencia de Bases , Cannabis/genética , Dronabinol/biosíntesis , Transferasas Intramoleculares/genética , Datos de Secuencia Molecular , Proteínas de Plantas/genética , Sintasas Poliquetidas/genética , Sintasas Poliquetidas/metabolismo
10.
Zootaxa ; 3774: 83-9, 2014 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-24871407

RESUMEN

Monoxia obesula Blake, 1939, a species native to North America, is newly found in Sardinia, Italy. This discovery constitutes the first report of the species from Europe, as well as the first report from outside of the U.S.A. The species is redescribed and illustrated, and errors in the original description are corrected. Host plants are species of Atriplex and Chenopodium occurring in saline habitats.


Asunto(s)
Escarabajos/anatomía & histología , Escarabajos/clasificación , Animales , Ecosistema , Femenino , Especies Introducidas , Italia , Masculino , Estados Unidos
11.
BMC Plant Biol ; 13: 12, 2013 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-23347725

RESUMEN

BACKGROUND: Bitter acids (e.g. humulone) are prenylated polyketides synthesized in lupulin glands of the hop plant (Humulus lupulus) which are important contributors to the bitter flavour and stability of beer. Bitter acids are formed from acyl-CoA precursors derived from branched-chain amino acid (BCAA) degradation and C5 prenyl diphosphates from the methyl-D-erythritol 4-phosphate (MEP) pathway. We used RNA sequencing (RNA-seq) to obtain the transcriptomes of isolated lupulin glands, cones with glands removed and leaves from high α-acid hop cultivars, and analyzed these datasets for genes involved in bitter acid biosynthesis including the supply of major precursors. We also measured the levels of BCAAs, acyl-CoA intermediates, and bitter acids in glands, cones and leaves. RESULTS: Transcripts encoding all the enzymes of BCAA metabolism were significantly more abundant in lupulin glands, indicating that BCAA biosynthesis and subsequent degradation occurs in these specialized cells. Branched-chain acyl-CoAs and bitter acids were present at higher levels in glands compared with leaves and cones. RNA-seq analysis showed the gland-specific expression of the MEP pathway, enzymes of sucrose degradation and several transcription factors that may regulate bitter acid biosynthesis in glands. Two branched-chain aminotransferase (BCAT) enzymes, HlBCAT1 and HlBCAT2, were abundant, with gene expression quantification by RNA-seq and qRT-PCR indicating that HlBCAT1 was specific to glands while HlBCAT2 was present in glands, cones and leaves. Recombinant HlBCAT1 and HlBCAT2 catalyzed forward (biosynthetic) and reverse (catabolic) reactions with similar kinetic parameters. HlBCAT1 is targeted to mitochondria where it likely plays a role in BCAA catabolism. HlBCAT2 is a plastidial enzyme likely involved in BCAA biosynthesis. Phylogenetic analysis of the hop BCATs and those from other plants showed that they group into distinct biosynthetic (plastidial) and catabolic (mitochondrial) clades. CONCLUSIONS: Our analysis of the hop transcriptome significantly expands the genomic resources available for this agriculturally-important crop. This study provides evidence for the lupulin gland-specific biosynthesis of BCAAs and prenyl diphosphates to provide precursors for the production of bitter acids. The biosynthetic pathway leading to BCAAs in lupulin glands involves the plastidial enzyme, HlBCAT2. The mitochondrial enzyme HlBCAT1 degrades BCAAs as the first step in the catabolic pathway leading to branched chain-acyl-CoAs.


Asunto(s)
Ciclohexenos/metabolismo , Perfilación de la Expresión Génica/métodos , Humulus/genética , Humulus/metabolismo , Terpenos/metabolismo , Humulus/enzimología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transducción de Señal
12.
BMC Plant Biol ; 13: 144, 2013 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-24074460

RESUMEN

BACKGROUND: The ubiquitous, non-proteinaceous amino acid GABA (γ-aminobutyrate) accumulates in plants subjected to abiotic stresses such as chilling, O2 deficiency and elevated CO2. Recent evidence indicates that controlled atmosphere storage causes the accumulation of GABA in apple (Malus x domestica Borkh.) fruit, and now there is increasing interest in the biochemical mechanisms responsible for this phenomenon. Here, we investigated whether this phenomenon could be mediated via Ca(2+)/calmodulin (CaM) activation of glutamate decarboxylase (GAD) activity. RESULTS: GAD activity in cell-free extracts of apple fruit was stimulated by Ca(2+)/CaM at physiological pH, but not at the acidic pH optimum. Based on bioinformatics analysis of the apple genome, three apple GAD genes were identified and their expression determined in various apple organs, including fruit. Like recombinant Arabidopsis GAD1, the activity and spectral properties of recombinant MdGAD1 and MdGAD2 were regulated by Ca(2+)/CaM at physiological pH and both enzymes possessed a highly conserved CaM-binding domain that was autoinhibitory. In contrast, the activity and spectral properties of recombinant MdGAD3 were not affected by Ca(2+)/CaM and they were much less sensitive to pH than MdGAD1, MdGAD2 and Arabidopsis GAD1; furthermore, the C-terminal region neither bound CaM nor functioned as an autoinhibitory domain. CONCLUSIONS: Plant GADs typically differ from microbial and animal GAD enzymes in possessing a C-terminal 30-50 amino acid residue CaM-binding domain. To date, rice GAD2 is the only exception to this generalization; notably, the C-terminal region of this enzyme still functions as an autoinhibitory domain. In the present study, apple fruit were found to contain two CaM-dependent GADs, as well as a novel CaM-independent GAD that does not possess a C-terminal autoinhibitory domain.


Asunto(s)
Calmodulina/metabolismo , Frutas/enzimología , Glutamato Descarboxilasa/metabolismo , Malus/enzimología , Proteínas de Plantas/metabolismo , Calmodulina/genética , Frutas/genética , Glutamato Descarboxilasa/genética , Malus/genética , Proteínas de Plantas/genética
13.
Sci Rep ; 13(1): 3160, 2023 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-36823255

RESUMEN

Superficial skin swab collections are inherently low-quality and may be of little clinical value due to their poor sensitivity and specificity. Clinical microbiology laboratories can use Gram smears to screen and differentiate higher and lower quality specimens to direct the extent of potential pathogen work up, including antimicrobial susceptibility testing (AST). We compared the impact of two different smear grading approaches to our current reporting practices for superficial wound swab cultures. Two variations of the Q score methodology (low power under 10X (QS10) and high power under 100X (QS100) were compared to our existing oil immersion method (OM100) (100X). We further evaluated the QS100 method by scoring superficial swab smears previously screened by OM100 from cultures submitted between November 2018 and December 2019. No significant difference in the number of low-quality specimens (N = 50) was identified by QS10 or QS100 grading (N = 9; 18%; N = 8; 16% respectively). Among 968 additional QS100 screened smears, 67 (6.9%) low quality swabs were identified and 7.4% fewer organisms (76/1020 organisms) would require reporting with AST. Implementing the Q score for superficial wound swab cultures would provide minimal improvements in their clinical relevance, laboratory quality and efficiency in our laboratory due to the low number of poor-quality swabs received.


Asunto(s)
Servicios de Laboratorio Clínico , Manejo de Especímenes , Manejo de Especímenes/métodos , Sensibilidad y Especificidad , Laboratorios
14.
Microbiol Spectr ; 11(1): e0482822, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36622222

RESUMEN

The epidemiology and treatment of typhoid fever are complicated by the emergence and spread of Salmonella enterica subsp. enterica serovar Typhi lineages with resistance to many antimicrobial agents critical for therapy. Current information on the susceptibility patterns of S. Typhi isolates identified in regions where typhoid fever is not endemic is important as these are often acquired after traveling to countries of endemicity where resistant strains circulate. Here, we report a 10-year retrospective survey of S. Typhi antimicrobial susceptibility patterns among 858 unique patient isolates that underwent reference laboratory testing in Ontario, Canada, between 2010 and 2019. Antimicrobial susceptibility patterns remained stable for ampicillin (average, 78.7% susceptible), azithromycin (average, 99.4% susceptible) ertapenem (average, 100.0% susceptible), meropenem (average, 100.0% susceptible), and trimethoprim-sulfamethoxazole (average, 78.2% susceptible) during the study period; however, nonsusceptibility to ciprofloxacin and ceftriaxone increased. While ceftriaxone-resistant isolates comprised 1.6% of the total isolates overall, they represented 10.1% of the total isolates tested in 2019, indicating a significant increase over time. Our findings suggest that when selecting empirical therapy, health care providers should strongly consider current trends in antimicrobial susceptibility and investigate the patient's exposure risk to gauge whether a suspected typhoid infection may be caused by a potentially resistant S. Typhi strain. IMPORTANCE This work provides an updated summary of the antimicrobial susceptibility patterns among Salmonella Typhi strains isolated from patients in Ontario, Canada.


Asunto(s)
Salmonella enterica , Fiebre Tifoidea , Humanos , Fiebre Tifoidea/tratamiento farmacológico , Fiebre Tifoidea/epidemiología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Ceftriaxona , Serogrupo , Ontario/epidemiología , Estudios Retrospectivos , Pruebas de Sensibilidad Microbiana , Farmacorresistencia Bacteriana
15.
Zootaxa ; 5227(1): 127-136, 2023 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-37044490

RESUMEN

Pachyonychis paradoxus Clark, 1860 and Pachyonychus paradoxus Melsheimer, 1847 are two species of Alticini whose strikingly similar names have led to significant confusion in the past. Recent study of American Oedionychina Chapuis, 1875 raised doubts about the validity of the subtribal placement of Pachyonychis Clark. Although general characteristics put this genus in Oedionychina, other features, especially the unusual shape of the pronotum, suggested that this monotypic genus would belong in Monoplatina Chapuis, 1875 instead. To collect evidence for the validity of its current placement, we compared external and genitalic morphology of both species to other members of Monoplatina and Oedionychina. Here we present images and descriptions of female genitalia for both species and male genitalia of Pachyonychus paradoxus Melsheimer, to our knowledge the first of their kind, and we conclude that the evidence supports the current subtribal placement of these two genera. Lectotypes are designated for both Pachyonychis paradoxus Clark and Pachyonychus paradoxus Melsheimer.


Asunto(s)
Escarabajos , Femenino , Masculino , Animales , Estructuras Animales/anatomía & histología , Genitales
16.
J Biol Chem ; 286(11): 9338-50, 2011 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-21212263

RESUMEN

Lombricine kinase is a member of the phosphagen kinase family and a homolog of creatine and arginine kinases, enzymes responsible for buffering cellular ATP levels. Structures of lombricine kinase from the marine worm Urechis caupo were determined by x-ray crystallography. One form was crystallized as a nucleotide complex, and the other was substrate-free. The two structures are similar to each other and more similar to the substrate-free forms of homologs than to the substrate-bound forms of the other phosphagen kinases. Active site specificity loop 309-317, which is disordered in substrate-free structures of homologs and is known from the NMR of arginine kinase to be inherently dynamic, is resolved in both lombricine kinase structures, providing an improved basis for understanding the loop dynamics. Phosphagen kinases undergo a segmented closing on substrate binding, but the lombricine kinase ADP complex is in the open form more typical of substrate-free homologs. Through a comparison with prior complexes of intermediate structure, a correlation was revealed between the overall enzyme conformation and the substrate interactions of His(178). Comparative modeling provides a rationale for the more relaxed specificity of these kinases, of which the natural substrates are among the largest of the phosphagen substrates.


Asunto(s)
Anélidos/enzimología , Simulación por Computador , Modelos Moleculares , Fosfotransferasas (Aceptor del Grupo Nitrogenado)/química , Adenosina Difosfato/química , Adenosina Difosfato/metabolismo , Adenosina Trifosfato/química , Adenosina Trifosfato/metabolismo , Animales , Dominio Catalítico , Cristalografía por Rayos X , Resonancia Magnética Nuclear Biomolecular , Fosfotransferasas (Aceptor del Grupo Nitrogenado)/metabolismo , Estructura Secundaria de Proteína
17.
Biochem Biophys Res Commun ; 427(1): 212-7, 2012 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-22995310

RESUMEN

Arginine kinase catalyzes the reversible transfer of a phosphoryl group between ATP and l-arginine and is a monomeric homolog of the human enzyme creatine kinase. Arginine and creatine kinases belongs to the phosphagen kinase family of enzymes, which consists of eight known members, each of which is specific for its own phosphagen. Here, the source of phosphagen specificity in arginine kinase is investigated through the use of phosphagen analogs. Crystal structures have been determined for Limulus polyphemus arginine kinase with one of four arginine analogs bound in a transition state analog complex: l-ornithine, l-citrulline, imino-l-ornithine, and d-arginine. In all complexes, the enzyme achieves a closed conformation very similar to that of the cognate transition state analog complex, but differences are observed in the configurations of bound ligands. Arginine kinase exhibits no detectable activity towards ornithine, citrulline, or imino-l-ornithine, and only trace activity towards d-arginine. The crystal structures presented here demonstrate that phosphagen specificity is derived neither from a lock-and-key mechanism nor a modulation of induced-fit conformational changes, but potentially from subtle distortions in bound substrate configurations.


Asunto(s)
Adenosina Difosfato/química , Arginina Quinasa/química , Arginina/química , Citrulina/química , Cangrejos Herradura/enzimología , Nitratos/química , Animales , Dominio Catalítico , Cristalografía por Rayos X , Estructura Terciaria de Proteína
18.
IDCases ; 27: e01395, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35059295

RESUMEN

Loofah sponges have been implicated in skin and soft tissue infections due to their ability to harbor bacteria and cause microtrauma to the skin. In this case report, we describe a case of impetigo and cellulitis due to Streptococcus pyogenes complicated by secondary spread through loofah sponge use. The same organism was cultured from the infected body sites and loofah sponge, and a comparative genomic analysis confirmed that the isolates were identical.

19.
Zookeys ; 1080: 21-52, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35068963

RESUMEN

Leaf beetles (Coleoptera: Chrysomelidae) constitute a family of abundant, diverse, and ecologically important herbivorous insects, due to their high specificity with host plants, a close association with vegetation and a great sensitivity to microclimatic variation (factors that are modified gradually during the rainy and dry seasons). Therefore, the effects of seasonality (rainy and dry seasons) and microclimate on the community attributes of chrysomelids were evaluated in a semideciduous tropical forest fragment of northeastern Mexico. Monthly sampling was conducted, between March 2016 and February 2017, with an entomological sweep net in 18 plots of 20 × 20 m, randomly distributed from 320 to 480 m a.s.l. Seven microclimatic variables were simultaneously recorded during each of the samplings, using a portable weather station. In total, 216 samples were collected at the end of the study, of which 2,103 specimens, six subfamilies, 46 genera, and 71 species were obtained. The subfamily Galerucinae had the highest number of specimens and species in the study area, followed by Cassidinae. Seasonality caused significant changes in the abundance and number of leaf beetle species: highest richness was recorded in the rainy season, with 60 species, while the highest diversity (lowest dominance and highest H' index) was obtained in the dry season. Seasonal inventory completeness of leaf beetles approached (rainy season) or was higher (dry season) than 70%, while the faunistic similarity between seasons was 0.63%. The outlying mean index was significant in both seasons; of the seven microclimatic variables analyzed, only temperature, heat index, evapotranspiration and wind speed were significantly related to changes in abundance of Chrysomelidae. Association between microclimate and leaf beetles was higher in the dry season, with a difference in the value of importance of the abiotic variables. The results indicated that each species exhibited a different response pattern to the microclimate, depending on the season, which suggests that the species may exhibit modifications in their niche requirements according to abiotic conditions. However, the investigations must be replicated in other regions, in order to obtain a better characterization of the seasonal and microclimatic influence on the family Chrysomelidae.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA