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Urinary tract infections (UTIs) caused by multidrug-resistant and extended-spectrum β-lactamase-producing uropathogenic Escherichia coli are a worldwide concern. We report the draft genome of E. coli U13824 isolated from a female outpatient with UTI. This genome's availability strengthens the genomic surveillance of antimicrobial resistance and the spreading of these strains., Competing Interests: The authors declare no conflict of interest.

The professional identity of scientists has historically been cultivated to value research over teaching, which can undermine initiatives that aim to reform science education. Course-Based Research Experiences (CRE) and the inclusive Research and Education Communities (iREC) are two successful and impactful reform efforts that integrate research and teaching. The aim of this study is to explicate the professional identity of instructors who implement a CRE within an established iREC and to explore how this identity contributes to the success of these programs. 97 CRE instructors from the Science Education Alliance (SEA) iREC participated in a 2-year, multi-stage, qualitative research project that involved weekly reflective journaling, autoethnographic description, small group evaluation and writing, and large-scale community checking. The resulting description of professional identity consisted of shared values (inclusivity, student success, community membership, ownership/agency, science, overcoming failure, and persistence), specified roles (mentor, advocate, scientist, educator, motivator, collaborator, community builder, learner, evaluator and project manager) and a stated sense of self (dedicated, resilient, pride in students, multiskilled, valued, community member, responsible and overworked). Analysis of individual reflective diary entries revealed how a professional identity underpinned and facilitated the ways in which faculty addressed challenges that arose and worked towards the success of every student. It is the self-concept of the professional identity of the instructor in the context of the CRE classroom that directed the extended commitment and effort that these instructors evidently put into their work with students, which facilitated student engagement, student persistence, and their collective scientific output. The study concludes that a professional identity of STEM faculty in the context of a CRE and iREC combines being a researcher and educator, and that this integrated identity is central for current initiatives aimed at transforming undergraduate STEM education.

Over the last two decades, there have been numerous initiatives to improve undergraduate student outcomes in STEM. One model for scalable reform is the inclusive Research Education Community (iREC). In an iREC, STEM faculty from colleges and universities across the nation are supported to adopt and sustainably implement course-based research - a form of science pedagogy that enhances student learning and persistence in science. In this study, we used pathway modelling to develop a qualitative description that explicates the HHMI Science Education Alliance (SEA) iREC as a model for facilitating the successful adoption and continued advancement of new curricular content and pedagogy. In particular, outcomes that faculty realize through their participation in the SEA iREC were identified, organized by time, and functionally linked. The resulting pathway model was then revised and refined based on several rounds of feedback from over 100 faculty members in the SEA iREC who participated in the study. Our results show that in an iREC, STEM faculty organized as a long-standing community of practice leverage one another, outside expertise, and data to adopt, implement, and iteratively advance their pedagogy. The opportunity to collaborate in this manner and, additionally, to be recognized for pedagogical contributions sustainably engages STEM faculty in the advancement of their pedagogy. Here, we present a detailed pathway model of SEA that, together with underpinning features of an iREC identified in this study, offers a framework to facilitate transformations in undergraduate science education.

The impact of contamination of water drainage ditches in the development of antibiotic-resistant bacteria has been scarcely studied in Mexico. In this regard, 101 isolates of E. coli were obtained from water samples from a ditch in Sinaloa, during one year. The antimicrobial resistant profiles, the presence of the class 1 integron and evolutionary relationship of intI1 sequences were determined. The 47.5% of strains were resistant and 5.9% multidrug resistant (MDR) with an average multiple antibiotic resistance index value of 0.45. The highest resistance was registered with β-lactam (39.6%) and quinolone (9.9%). The intI1 gene was detected in 11.9% of the isolates, and no association with MDR was found. Sequence were associated with human and animal host isolates. MDR E. coli isolates with intI1 gene highlight the potential risk of the ditch's water to human health. An attenuation effect of MDR E. coli isolates in the outlet water was observed.

Course-based research pedagogy involves positioning students as contributors to authentic research projects as part of an engaging educational experience that promotes their learning and persistence in science. To develop a model for assessing and grading students engaged in this type of learning experience, the assessment aims and practices of a community of experienced course-based research instructors were collected and analyzed. This approach defines four aims of course-based research assessment - 1) Assessing Laboratory Work and Scientific Thinking; 2) Evaluating Mastery of Concepts, Quantitative Thinking and Skills; 3) Appraising Forms of Scientific Communication; and 4) Metacognition of Learning - along with a set of practices for each aim. These aims and practices of assessment were then integrated with previously developed models of course-based research instruction to reveal an assessment program in which instructors provide extensive feedback to support productive student engagement in research while grading those aspects of research that are necessary for the student to succeed. Assessment conducted in this way delicately balances the need to facilitate students' ongoing research with the requirement of a final grade without undercutting the important aims of a CRE education.

Fluorination of pharmaceutical agents has afforded crucial modifications to their pharmacological profiles, leading to important advances in medicinal chemistry. On the other hand, metallodrugs are considered to be valuable candidates in the treatment of several diseases, albeit with the caveat that they may exhibit pharmacological disadvantages, such as poor water solubility, low bioavailability and short circulating time. To surmount these limitations, two approaches have been developed: one based on the design of novel metallodrug-delivering carriers and the other based on optimizing the structure of the ligands bound to the metal center. In this context, fluorination of the ligands may bring beneficial changes (physicochemical and biological) that can help to elude the aforementioned drawbacks. Thus, in this review, we discuss the use of fluorinated ligands in the design of metallodrugs that may exhibit potential anticancer activity.

Background: Escherichia coli strains include both commensal and virulent clones distributed in different phylogenetic groups. Antimicrobial resistance is an increasingly serious public health threat at the global level and integrons are important mobile genetic elements involved in resistance dissemination. This paper aims to determine the phylogenetic groups and presence of class 1 (intl1) and 2 (intl2) integrons in E. coli clinical isolates from children with diarrhoea, and to associate these characteristics with their antimicrobial resistance., Methods: Phylogeny and presence of integrons (intl1 and intl2) were analysed by PCR and amplicon sequencing in 70 E. coli isolates from children with and without diarrhoea (35 of each group) from Sinaloa, Mexico; these variables were analysed for correlation with the antimicrobial resistance profile of the isolates., Results: The most frequent phylogroups were A (42.9%) and B2 (15.7%). The E. coli isolates from children with diarrhoea were distributed in all phylogroups; while strains from children without diarrhoea were absent from phylogroups C, E, and clade I. The 17.1% of the isolates carried integrons (15.7% intI1 and 1.4% intI2); 28.6% of the isolates from children with diarrhoea showed the class 1 integron. Strains of phylogroup A showed the highest frequency of integrons (33.3%). The association of multidrug resistance and the presence of integrons was identified in 58.3% of strains isolated from children with diarrhoea included in phylogroups A and B2. The sequence analysis of intl1 and intl2 showed silent point mutations and similarities with plasmids of some APEC and AIEC strains., Conclusion: Commensal E. coli strains are potential disseminators of antimicrobial resistance, and the improvement in the use of antimicrobials to treat childhood diarrhoea is essential for the control of such resistance., (Copyright © 2019 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Human gnathostomiasis, which is endemic in Mexico, is a worldwide health concern. It is mainly caused by the consumption of raw or insufficiently cooked fish containing the advanced third-stage larvae (AL3A) of Gnathostoma species. The diagnosis of gnathostomiasis is based on epidemiological surveys and immunological diagnostic tests. When a larva is recovered, the species can be identified by molecular techniques. Polymerase chain reaction (PCR) amplification of the second internal transcription spacer (ITS-2) is useful to identify nematode species, including Gnathostoma species. This study aims to develop a duplex-PCR amplification method of the ITS-2 region to differentiate between the Gnathostoma binucleatum and G. turgidum parasites that coexist in the same endemic area, as well as to identify the Gnathostoma larvae recovered from the biopsies of two gnathostomiasis patients from Sinaloa, Mexico. The duplex PCR established based on the ITS-2 sequence showed that the length of the amplicons was 321 bp for G. binucleatum and 226 bp for G. turgidum. The amplicons from the AL3A of both patients were 321 bp. Furthermore, the length and composition of these amplicons were identical to those deposited in GenBank as G. binucleatum (accession No. JF919679), corroborating our previous morphological finding that G. binucleatum is the etiological agent for human gnathostomiasis in the endemic area of Sinaloa, Mexico.

Objectives: In this study, we report the draft genome sequence of a multidrug-resistant (MDR)Escherichia coli strain recovered from stool sample of an outpatient infant girl with acute diarrheal infection in Mexico., Methods: Antimicrobial susceptibility testing and PCR-based detection of diarrheagenic E. coli (DEC) were performed. In addition, genomic DNA from E. coli strain M51-3 was sequenced using Ion Torrent PGM platform with 200-bp chemistry and generated reads were de novo assembled using SPAdes v3.11. The draft genome was annotated and analyzed regarding multilocus sequence typing (MLST), serotyping, fimH typing, plasmid replicons, acquired antimicrobial resistance and virulence genes using web tools available at the Center for Genomic Epidemiology., Results: A draft genome comprising 5 088 545 bp in length and 5308 protein-coding sequences was generated. In silico typification revealed that E. coli strain M51-3 belongs to ST131-O25:H4-H30 pandemic subclone. Several genes associated with resistance to β-lactams [bla TEM-1B ], aminoglycosides [aph(3'')-Ib, aadA5, aph(6)-Id and aac(3)-IId], sulfonamides [sul1 and sul2], trimethoprim [dfrA17], and tetracycline [tet(A)] were identified. Besides, point mutations in gyrA, parC, and parE genes were detected. Interestingly, the enterotoxin-coding virulence gene senB was evidenced., Conclusions: To our knowledge, this is the first draft genome of an E. coli ST131-O25:H4-H30 strain recovered from infant diarrheal stool sample in Mexico. The genome sequence of E. coli M51-3 presented here will be helpful to understand the genomic diversity of this highly virulent and MDR successfully pandemic bacterial pathogen., (Copyright © 2019 International Society for Antimicrobial Chemotherapy. Published by Elsevier Ltd. All rights reserved.)

Objectives: Methicillin-resistant Staphylococcus aureus (MRSA) is a human pathogen of great concern owing to its antimicrobial resistance and virulence properties. Here we report the first draft genome sequence of a mecA-negative community-associated MRSA strain isolated from a healthy young Mexican paediatric carrier in order to reveal the genomic structure underlying the multidrug-resistant phenotype and to discover the virulence properties of this strain., Methods: The draft genome sequence of S. aureus L401 was obtained using an Ion Torrent ™ PGM platform. De novo assembled contigs were annotated, and antimicrobial resistance genes and virulence factors were identified using ResFinder and VirulenceFinder, respectively. In addition, a mutational survey of native pbp, gdpP and yjbH genes was performed. In silico multilocus sequence typing (MLST) and spa typing were also performed., Results: S. aureus L401 has a genome size of 2 831 587 bp with 2799 protein-coding sequences. Various antimicrobial resistance genes conferring resistance to aminoglycosides, β-lactams, fluoroquinolones and macrolide-lincosamide-streptogramin B antimicrobials were found. Although both mecA and staphylococcal cassette chromosome mec (SCCmec) elements were absent, a missense mutation in PBP3 was identified. Moreover, genes encoding exfoliative toxin A, γ- and β-haemolysin, and several enterotoxins were also identified. S. aureus L401 belongs to ST109 and spa type t209., Conclusion: The availability of this genome will allow an insight into S. aureus resistance and virulence determinants as well as its epidemiology, lineage, evolution and genomic features involved in the paediatric commensal carriage., (Copyright © 2019 International Society for Antimicrobial Chemotherapy. Published by Elsevier Ltd. All rights reserved.)

We present here the first draft genome sequence of a typical enteropathogenic Escherichia coli serotype O55:H51 strain, M15-4, isolated from a 2-month-old infant girl with acute diarrhea. The study of this Mexican isolate will provide insights to the virulence and drug resistance traits involved in its pathogenic potential., (Copyright © 2018 Magaña-Lizárraga et al.)

We report here the first draft genome sequence of a Mexican communitarian methicillin-resistant Staphylococcus epidermidis (MRSE) strain whose genome harbors a wide variety of resistance determinants. The availability of this genome will allow the study of antibiotic resistance in Mexican staphylococci from a genomic perspective., (Copyright © 2017 Magaña-Lizárraga et al.)