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Abstract Recent genomic analyses have revealed that microbial communities are predominantly composed of persistent, sequence-discrete species and intraspecies units (genomovars), but the mechanisms that create and maintain these units remain unclear. By analyzing closely-related isolate genomes from the same or related samples and identifying recent recombination events using a novel bioinformatics methodology, we show that high ecological cohesiveness coupled to frequent-enough and unbiased (i.e., not selection-driven) horizontal gene flow, mediated by homologous recombination, often underlie these diversity patterns. Ecological cohesiveness was inferred based on greater similarity in temporal abundance patterns of genomes of the same vs. different units, and recombination was shown to affect all sizable segments of the genome (i.e., be genome-wide) and have two times or greater impact on sequence evolution than point mutations. These results were observed in both Salinibacter ruber, an environmental halophilic organism, and Escherichia coli, the model gut-associated organism and an opportunistic pathogen, indicating that they may be more broadly applicable to the microbial world. Therefore, our results represent a departure compared to previous models of microbial speciation that invoke either ecology or recombination, but not necessarily their synergistic effect, and answer an important question for microbiology: what a species and a subspecies are.

Rafael Pichardo-Rodriguez,1 Valeria Altuna-Moscoso,1 Karen Aviles-Antezana,1 Alondra Lorena Cahuana-Mendoza,1 Antonio André Challco Alvarado,1 Cristhian Gonzales-Rospigliosi,1 Shirley Oscco-Coila,1 Enzo Rafael-Tarazona,1 Marcos Saavedra-Velasco,1 Liz Cordova-Cueva,1 Jhony A De La Cruz-Vargas,1 Fernando Munayco-Guillen,1,2 Herney Andrés García-Perdomo3 1Instituto de Investigaciones en Ciencias Biomédicas (INICIB), Universidad Ricardo Palma, Lima, Perú; 2Instituto Nacional de Oftalmología (INO), Lima, Peru; 3Division of Urology/Uro oncology, Department of Surgery, School of Medicine, Universidad del Valle, Cali, ColombiaCorrespondence: Rafael Pichardo-Rodriguez, Email rafael_martin1352@hotmail.comObjective: To determine the quality of systematic reviews submitted as a thesis in the Medical School of Ricardo Palma University.Methods: We conducted a systematic review. We included systematic reviews submitted as theses from Ricardo Palma University, and we excluded narrative reviews, editorials, clinical experiments, and those with incomplete data. We performed a structured search on EMBASE, PubMed, Scopus, and Institutional Repository from the Ricardo Palma University and RENATI. The risk of bias assessment was performed through the AMSTAR-2 and the modified AMSTAR-2 tools. The primary outcome was review quality. A qualitative synthesis of the information was performed.Results: One thousand four hundred eighty-seven theses were identified, and exclusion criteria were applied, whereby 11 theses were selected for review and thorough consultation. Of the 11 selected theses, and through the AMSTAR-2 and modified AMSTAR-2 tools, the findings reached were that 90.9% of the included theses presented critically low quality that was not modified even when the quality was reevaluated after its publication as a scientific article.Conclusion: The systematic reviews presented as undergraduate thesis in the Medical School of Ricardo Palma University showed low and critically low quality. Improvement in systematic review training is required for both students and institutional advisors.Keywords: thesis, systematic review, medical school

A la luz de la diversidad de prácticas de lecturadel mundo de hoy se cuestiona la concepción y elquehacer de la animación de la lectura y se proponenalgunas pautas para su diseño. La lectura comoplacer, las construcciones sociales sobre ella y lahomogeneización de los lectores son los referentespara plantearse por qué y para qué hay que formarlectores.

Abstract The SeqCode, formally called the Code of Nomenclature of Prokaryotes Described from Sequence Data, is a new code of nomenclature in which genome sequences are the nomenclatural types for the names of prokaryotic species. While similar to the International Code of Nomenclature of Prokaryotes (ICNP) in structure and rules of priority, it does not require the deposition of type strains in international culture collections. Thus, it allows for the formation of permanent names for uncultured prokaryotes whose nearly complete genome sequences have been obtained directly from environmental DNA as well as other prokaryotes that cannot be deposited in culture collections. Because the diversity of uncultured prokaryotes greatly exceeds that of readily culturable prokaryotes, the SeqCode is the only code suitable for naming the majority of prokaryotic species. The start date of the SeqCode was January 1, 2022, and the online Registry (https://seqco.de/) was created to ensure valid publication of names. The SeqCode recognizes all names validly published under the ICNP before 2022. After that date, names validly published under the SeqCode compete with ICNP names for priority. As a result, species can have only one name, either from the SeqCode or ICNP, enabling effective communication and the creation of unified taxonomies of uncultured and cultured prokaryotes. The SeqCode is administered by the SeqCode Committee, which is comprised of the SeqCode Community and elected administrative components. Anyone with an interest in the systematics of prokaryotes is encouraged to join the SeqCode Community and participate in the development of this resource.

Abstract What a strain is and how many strains make up a natural bacterial population remain elusive concepts despite their apparent importance for assessing the role of intra-population diversity in disease emergence or response to environmental perturbations. To advance these concepts, we sequenced 138 randomly selected Salinibacter ruber isolates from two solar salterns and assessed these genomes against companion short-read metagenomes from the same samples. The distribution of genome-aggregate average nucleotide identity (ANI) values among these isolates revealed a bimodal distribution, with four-fold lower occurrence of values between 99.2% and 99.8% relative to ANI >99.8% or 99.99% and shared gene-content >99.0% to define strains. Using these thresholds and extrapolating from how many metagenomic reads each genomovar uniquely recruited, we estimated that –although our 138 isolates represented about 80% of the Sal. ruber population– the total population in one saltern pond is composed of 5,500 to 11,000 genomovars, the great majority of which appear to be rare in-situ. These data also revealed that the most frequently recovered isolate in lab media was often not the most abundant genomovar in-situ, suggesting that cultivation biases are significant, even in cases that cultivation procedures are thought to be robust. The methodology and ANI thresholds outlined here should represent a useful guide for future microdiversity surveys of additional microbial species.

ABSTRACTLarge-scale surveys of prokaryotic communities (metagenomes), as well as isolate genomes, have revealed that their diversity is predominantly organized in sequence-discrete units that may be equated to species. Specifically, genomes of the same species commonly show genome-aggregate average nucleotide identity (ANI) >95% among themselves and ANI 99.99% proposed). Collectively, our results should facilitate future micro-diversity studies across clinical or environmental settings because they provide a more natural definition of intra-species units of diversity.IMPORTANCEBacterial strains and clonal complexes are two cornerstone concepts for microbiology that remain loosely defined, which confuses communication and research. Here we identify a natural gap in genome sequence comparisons among isolate genomes of all well-sequenced species that has gone unnoticed so far and could be used to more accurately and precisely define these and related concepts compared to current methods. These findings advance the molecular toolbox for accurately delineating and following the important units of diversity within prokaryotic species and thus should greatly facilitate future epidemiological and micro-diversity studies across clinical and environmental settings.

Fernando Munayco-Guillén,1,2 Miguel Angel Vazquez-Membrillo,1,2 Marlon Rafael Garcia-Roa,1,2 Jhony Alberto De La Cruz-Vargas,3 Herney Andrés García-Perdomo,4 Rafael Pichardo-Rodriguez3 1Department of Retina and Vitreous Surgery, Instituto Mexicano de Oftalmología (IMO), Querétaro, México; 2Universidad Nacional Autónoma de México (UNAM), México City, México; 3Instituto de Investigaciones en Ciencias Biomédicas (INICIB), Universidad Ricardo Palma, Lima, Perú; 4Division of Urology/Urooncology, Deparment of Surgery, School of Medicine, Universidad del Valle, Cali, ColombiaCorrespondence: Fernando Munayco-Guillén, Fray Servando Teresa de Mier 202, Quintas del Marqués, Querétaro, México, Tel +51 985-558886, Email fernando.munayco.guillen@gmail.comPurpose: It has been reported that intravitreal Ziv-aflibercept is a safe and effective drug for the treatment of diabetes macular edema (DME). The objective of this study was to evaluate in a real-life setting, the efficacy of intravitreal Ziv-aflibercept in the treatment of DME after the administration of three consecutive monthly doses.Methods: A single arm, prospective cohort study. We included patients with DME who received three doses of intravitreal Ziv-aflibercept. Data such as best corrected visual acuity (BCVA) and tomographic biomarkers before treatment and a month after the third dose were collected. DME was staged using the Panozzo classification.Results: Thirty-eight patients participated for a total of 53 eyes. The mean age was 59 ± 8.1 years. We observed significant changes after the third dose in the parameters studied (BCVA in LogMAR pre-treatment (0.6 ± 0.33) and post-treatment (0.4 ± 0.29) [p< 0.001], macular thickness pre-treatment (501 ± 167 μm) and post-treatment (324 ± 114 μm) [p< 0.001], macular volume pre-treatment 10.8 (7.5– 17.8) mm3 and post-treatment 9.3 (0– 13.6) mm3 [p< 0.005]). And 73.6% of the patients presented an advanced severe stage during their pre-treatment evaluation and after post-treatment, 64.2% of the patients no longer presented edema. No systemic or ocular adverse events occurred.Conclusion: The use of three consecutive monthly doses of intravitreal Ziv-aflibercept in a real-life setting is effective and safe in the management of diabetic macular edema.Keywords: antiangiogenic, diabetes mellitus, intravitreal injection, macular edema, optical coherence tomography, Ziv-aflibercept

We present a 30-year-old woman with a solitary circumscribed neuroma (also known as palisaded encapsulated neuroma) diagnosed after surgical excision. We describe the histopathologic correlation and the dermoscopic features we found in this tumor, which have not been previously reported in the literature to our knowledge.

Agustin Melo-Carrillo,1,2 Raul Rodriguez,3 Sait Ashina,1,2 Brittany Lipinski,3 Paul Hart,4 Rami Burstein1,2 1Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA; 2Department of Anesthesia, Harvard Medical School, Boston, MA, USA; 3Delray Center for Healing, Delray Beach, FL, USA; 4Heart to Heart, Lenexa, KS, USACorrespondence: Rami Burstein, Tel +1 617 735-2832, Fax +1 617 735-2833, Email rburstei@bidmc.harvard.eduBackground and Goals: Psychotherapy is one of the most highly recommended and practiced approaches for the treatment of Generalized anxiety disorder (GAD). Commonly defined as excessive worry that is uncontrollable, GAD is one of the most prevalent psychiatric disorders. Anxiety is also one of the most common associated symptoms of migraine. Exposing migraineurs to narrow band green light (nbGL) reduces their anxiety and anxiety-like physiological symptoms such as throat tightness, shortness of breath, and palpitations. Here, we sought to determine whether the reduced anxiety described by our patients was secondary to the reduced headache or independent of it. The goal of the current study was therefore to determine whether exposure to nbGL can reduce anxiety in GAD patients who are not migraineurs.Patients and Methods: Included in this open-label, proof-of-concept, prospective study were 13 patients diagnosed with moderate-to-severe GAD. We used the State-Trait Anxiety Inventory Questionnaire (Y-1) to compare anxiety level before and after each 45-minutes psychotherapy session conducted in white light (WL) (intensity = 100± 5 candela/m2) vs nbGL (wavelength = 520± 10nm (peak ± range), intensity = 10± 5 candela/m2).Results: Here, we show that psychotherapy sessions conducted under nbGL increase positive and decrease negative feelings significantly more than psychotherapy sessions conducted under regular room light (χ2 = 0.0001).Conclusion: The findings provide initial evidence for the potential benefit of conducting psychotherapy sessions for patients suffering GAD under nbGL conditions. Given the absence of side effects or risks, we suggest that illuminating rooms used in psychotherapy with nbGL be considered an add-on to the treatment of GAD.Keywords: photophobia, migraine, psychotherapy, GAD, retina, depression