Correction: Epigenetic, psychological, and EEG changes after a 1-week retreat based on mindfulness and compassion for stress reduction in healthy adults: Study protocol of a cross-over randomized controlled trial.

[This corrects the article DOI: 10.1371/journal.pone.0283169.].

Epigenetic, psychological, and EEG changes after a 1-week retreat based on mindfulness and compassion for stress reduction in healthy adults: Study protocol of a cross-over randomized controlled trial.

INTRODUCTION: The main objective of the study will be to evaluate the effects of two widely used standardized mindfulness-based programs [Mindfulness-Based Stress Reduction (MBSR) and Compassion Cultivation Training (CCT)], on epigenetic, neurobiological, psychological, and physiological variables. METHODS: The programs will be offered in an intensive retreat format in a general population sample of healthy volunteer adults. During a 7-day retreat, participants will receive MBSR and CCT in a crossover design where participants complete both programs in random order. After finishing their first 3-day training with one of the two programs, participants will be assigned to the second 3-day training with the second program. The effects of the MBSR and CCT programs, and their combination, will be measured by epigenetic changes (i.e., DNA methylation biomarkers), neurobiological and psychophysiological measures (i.e., EEG resting state, EKG, respiration patterns, and diurnal cortisol slopes), self-report questionnaires belonging to different psychological domains (i.e., mindfulness, compassion, well-being, distress, and general functioning), and stress tasks (i.e., an Arithmetic Stress Test and the retrieval of negative autobiographical memories). These measures will be collected from both groups on the mornings of day 1 (pre-program), day 4 (after finishing the first program and before beginning the second program), and day 7 (post-second program). We will conduct a 3-month and a 12-month follow-up using only the set of self-report measures. DISCUSSION: This study aims to shed light on the neurobiological and psychological mechanisms linked to meditation and compassion in the general population. The protocol was registered at clinicaltrials.gov (Identifier: NCT05516355; August 23, 2022).

How do mindfulness and compassion programs improve mental health and well-being? The role of attentional processing of emotional information.

BACKGROUND AND OBJECTIVES: Although the benefits of Meditation-Based Programs are well documented, the mechanisms underlying these benefits have not been fully elucidated. Therefore, we examined whether: (1) formal training in mindfulness and compassion meditation modifies the distribution of attentional resources towards emotional information; and (2) whether changes in attentional processing of emotional information after the meditation programs mediate the improvements in psychological distress, emotion regulation, and well-being. METHODS: A sample of 103 participants enrolled in the study: 36 in the mindfulness program (MBSR), 30 in the compassion program (CCT), and 37 in the no-intervention comparison group (CG). The assessment before and after the programs included the completion of an emotional Attentional Blink task (AB) together with self-report measures of psychological distress, emotion regulation, and well-being. RESULTS: MBSR and CCT reduced similarly the AB deficit, whereas no changes occurred in the CG. This AB reduction was found for the different emotional and non-emotional stimuli (i.e., negative, positive, and neutral), showing a significant disengagement from first-target emotions and significant accessibility of second-target emotions to consciousness. The effects of both meditation programs on the psychological measures were mediated by changes in the AB and emotion regulation skills. LIMITATIONS: Due to our naturalistic design in a real-world community setting, random assignment of participants was not feasible. CONCLUSIONS: Meditation may promote more flexible and balanced attention to emotional information, which may be a key transdiagnostic mechanism underlying its benefits on emotional distress and well-being.

A compassion-based program to reduce psychological distress in medical students: A pilot randomized clinical trial.

OBJECTIVES: Physicians and medical students are subject to higher levels of psychological distress than the general population. These challenges have a negative impact in medical practice, leading to uncompassionate care. This pilot study aims to examine the feasibility of Compassion Cultivation Training (CCT) to reduce psychological distress and improve the well-being of medical students. We hypothesize that the CCT program, as compared to a waitlist control group, will reduce psychological distress (i.e., stress, anxiety, and depression) and burnout symptoms, while improving compassion, empathy, mindfulness, resilience, psychological well-being, and emotion-regulation strategies after the intervention. Furthermore, we hypothesize that these improvements will be maintained at a two-month follow-up. METHODS: Medical students were randomly assigned to an 8-week CCT or a Waitlist control group (WL). They completed self-report assessments at pre-intervention, post-intervention, and a 2-month follow-up. The outcomes measured were compassion, empathy, mindfulness, well-being, resilience, emotional regulation, psychological distress, burnout, and COVID-19 concern. Mixed-effects models and Reliable Change Index were computed. RESULTS: Compared with WL, CCT showed significant improvements in self-compassion, mindfulness, and emotion regulation, as well as a significant decrease in stress, anxiety, and emotional exhaustion component of burnout. Furthermore, some of these effects persisted at follow-up. No adverse effects of meditation practices were found. CONCLUSIONS: CCT enhanced compassion skills while reducing psychological distress in medical students, this being critical to preserving the mental health of physicians while promoting compassionate care for patients. The need for institutions to include this type of training is also discussed.

Long-term Effectiveness and Predictors of Transdiagnostic Internet-Delivered Cognitive Behavioral Therapy for Emotional Disorders in Specialized Care: Secondary Analysis of a Randomized Controlled Trial.

BACKGROUND: Transdiagnostic internet-delivered cognitive behavioral therapy (iCBT) for emotional disorders has been shown to be effective in specialized care in the short term. However, less is known about its long-term effects in this specific setting. In addition, predictors of long-term effectiveness may help to identify what treatments are more suitable for certain individuals. OBJECTIVE: This study aimed to analyze the long-term effectiveness of transdiagnostic iCBT compared with that of treatment as usual (TAU) in specialized care and explore predictors of long-term effectiveness. METHODS: Mixed models were performed to analyze the long-term effectiveness and predictors of transdiagnostic iCBT (n=99) versus TAU (n=101) in public specialized mental health care. Outcomes included symptoms of depression and anxiety, health-related quality of life (QoL), behavioral inhibition and behavioral activation, comorbidity, and diagnostic status (ie, loss of principal diagnosis) from baseline to 1-year follow-up. Sociodemographic characteristics (sex, age, and education) and clinical variables (principal diagnosis, comorbidity, and symptom severity at baseline) were selected as predictors of long-term changes. RESULTS: Compared with baseline, transdiagnostic iCBT was more effective than TAU in improving symptoms of depression (b=-4.16, SE 1.80, 95% CI -7.68 to -0.67), health-related QoL (b=7.63, SE 3.41, 95% CI 1.00-14.28), diagnostic status (b=-0.24, SE 0.09, 95% CI -1.00 to -0.15), and comorbidity at 1-year follow-up (b=-0.58, SE 0.22, 95% CI -1.00 to -0.15). From pretreatment assessment to follow-up, anxiety symptoms improved in both transdiagnostic iCBT and TAU groups, but no significant differences were found between the groups. Regarding the predictors of the long-term effectiveness of transdiagnostic iCBT compared with that of TAU, higher health-related QoL at follow-up was predicted by a baseline diagnosis of anxiety, male sex, and the use of psychiatric medication; fewer comorbid disorders at follow-up were predicted by older age and higher baseline scores on health-related QoL; and fewer depressive symptoms at follow-up were predicted by baseline diagnosis of depression. However, this pattern was not observed for baseline anxiety diagnoses and anxiety symptoms. CONCLUSIONS: The results suggest that transdiagnostic iCBT is more effective than TAU to target depressive symptoms among patients with emotional disorders. Anxiety symptoms remained stable at 1-year follow-up, with no differences between the groups. Results on predictors suggest that some groups of patients may obtain specific gains after transdiagnostic iCBT. Specifically, and consistent with the literature, patients with baseline depression improved their depression scores at follow-up. However, this pattern was not found for baseline anxiety disorders. More studies on the predictor role of sociodemographic and clinical variables in long-term outcomes of transdiagnostic iCBT are warranted. Future studies should focus on studying the implementation of transdiagnostic iCBT in Spanish public specialized mental health care. TRIAL REGISTRATION: ClinicalTrials.gov NCT02345668; https://clinicaltrials.gov/ct2/show/NCT02345668.

Initial Effectiveness Evaluation of the Unified Protocol for Transdiagnostic Treatment of Emotional Disorders for Homeless Women.

The purpose of this study is to evaluate the effectiveness of the Unified Protocol for Transdiagnostic Treatment of Emotional Disorders adapted for homeless women (UPHW). Eighty-one homeless women participated in this single-blinded quasi-experimental clinical trial, involving up to 12 sessions of group treatment, and 3-and 6-month follow-ups. The participants received either immediate treatment with the UPHW (n = 46) or delayed treatment, following a 12-week wait-list control period (WLC; n = 35). Primary outcomes included depression and anxiety. Secondary measures comprised positive and negative affect, psychological well-being, health perception, and social support. The UPHW resulted in significant improvement on measures of anxiety, depression and negative affect. Improvements in anxiety and depression were maintained over a 3-month follow-up period, but not at 6-month. The reliability of the clinical changes showed significant differences between UPHW and WLC for depression. Moreover, the inter-session assessment in the UPHW group showed a linear trend reduction for depression and anxiety scores along the 12 sessions. The clinical implications on the UPHW in social settings are also discussed.

Not all types of meditation are the same: Mediators of change in mindfulness and compassion meditation interventions.

BACKGROUND: The general aim of the study was to examine the relative effectiveness and mediators of change in standardized mindfulness and compassion interventions. METHODS: A sample of 431 participants enrolled in a Mindfulness-Based Stress Reduction program (MBSR = 277) and a Compassion Cultivation Training (CCT = 154). The assessment before and after the program included a set of outcomes and mediators measures. A three-step data analysis plan was followed: ANCOVAs, Reliable Change Index, and mediations (simple and multiple). RESULTS: Both interventions yielded increased mindfulness, decentering, body awareness, and self-compassion. Yet, present-moment awareness improvements (i.e., decentering, and body awareness) were significantly larger in the MBSR than in CCT, whereas socio-emotional changes (i.e., common humanity and empathic concern) were larger in the CCT than in MBSR. The magnitude of effect sizes ranged from medium to large. Furthermore, both mindfulness and compassion interventions yielded similar changes in psychological distress (i.e., stress, anxiety, and depression), maladaptive cognitive processes (i.e., rumination and thought suppression), and well-being. The mediation models showed that although the MBSR program seemingly relies on changes in present-moment awareness mechanisms (i.e., decentering and body awareness) to reduce psychological distress and to improve well-being, the CCT program seemingly achieves the same positive outcomes through changes in socio-emotional mechanisms (i.e., common-humanity and empathy concern). LIMITATIONS: Due to our naturalistic design in real-world community setting, it was infeasible to randomly assign participants to conditions. CONCLUSIONS: Our results suggest that mindfulness and compassion programs operate through different pathways to reduce psychological distress and to promote well-being.

Differences in stressful life events between men and women experiencing homelessness.

People experiencing homelessness are particularly vulnerable to experiencing stressful life events (SLEs) at some point in their lives; these SLEs are crucial for understanding the etiology and maintenance of homelessness. This study analyses the differences between men and women experiencing homelessness in the suffering of SLEs throughout their lives (childhood, adolescence, and adulthood). The sample consisted of a group of 293 people experiencing homelessness in Madrid (Spain): 156 men and 137 women. The results suggest that the number and type of SLEs experienced by men and women are different. In general, women experiencing homelessness suffer more SLEs than men in all periods of their lives. The differences in the level of sexual violence in childhood, sexual abuse in adulthood, and abuse by a spouse or partner are particularly striking. However, men experiencing homelessness score significantly higher than women for alcohol abuse, police complaints, arrest, and imprisonment throughout their lives. These findings have significant implications for the design of interventions and social policies that should be tailored to the specific needs of men and women who are homeless.

Effectiveness of a Transdiagnostic Guided Internet-Delivered Protocol for Emotional Disorders Versus Treatment as Usual in Specialized Care: Randomized Controlled Trial.

BACKGROUND: Anxiety disorders and depression (emotional disorders) are highly prevalent mental disorders. Extensive empirical evidence supports the efficacy of cognitive behavioral therapy (CBT) for the treatment of these disorders. However, there are still some barriers related to their dissemination and implementation, which make it difficult for patients to receive these treatments, especially in public health care settings where resources are limited. Recent advances in improving CBT dissemination encompass different perspectives. One is the transdiagnostic approach, which offers treatment protocols that can be used for a range of emotional disorders. Another approach is the use of the internet to reach a larger number of people who could benefit from CBT. OBJECTIVE: This study aimed to analyze the effectiveness and acceptability of a transdiagnostic internet-delivered protocol (EmotionRegulation) with human and automated guidance in patients from public specialized mental health care settings. METHODS: A 2-armed randomized controlled trial (RCT) was conducted to compare the effectiveness of EmotionRegulation with treatment as usual (TAU) in specialized mental health care. In all, 214 participants were randomly assigned to receive either EmotionRegulation (n=106) or TAU (n=108). Measurement assessments were conducted at pre- and postintervention and at a 3-month follow-up. RESULTS: The results revealed the superiority of EmotionRegulation over TAU on measures of depression (d=0.41), anxiety (d=0.35), and health-related quality of life (d=-0.45) at posttreatment, and these gains were maintained at the 3-month follow-up. Furthermore, the results for expectations and opinions showed that EmotionRegulation was well accepted by participants. CONCLUSIONS: EmotionRegulation was more effective than TAU for the treatment of emotional disorders in the Spanish public mental health system. The implications of this RCT, limitations, and suggestions for future research are discussed. TRIAL REGISTRATION: ClinicalTrials.gov NCT02345668; https://clinicaltrials.gov/ct2/show/NCT02345668.

Does mindfulness change the mind? A novel psychonectome perspective based on Network Analysis.

If the brain is a complex network of functionally specialized areas, it might be expected that mental representations could also behave in a similar way. We propose the concept of 'psychonectome' to formalize the idea of psychological constructs forming a dynamic network of mutually dependent elements. As a proof-of-concept of the psychonectome, networks analysis (NA) was used to explore structural changes in the network of constructs resulting from a psychological intervention. NA was applied to explore the effects of an 8-week Mindfulness-Based Stress Reduction (MBSR) program in healthy participants (N = 182). Psychological functioning was measured by questionnaires assessing five key domains related to MBSR: mindfulness, compassion, psychological well-being, psychological distress and emotional-cognitive control. A total of 25 variables, covering the five constructs, were considered as nodes in the NA. Participants significantly improved in most of the psychological questionnaires. More interesting from a network perspective, there were also significant changes in the topological relationships among the elements. Expected influence and strength centrality indexes revealed that mindfulness and well-being measures were the most central nodes in the networks. The nodes with highest topological change after the MBSR were attentional control, compassion measures, depression and thought suppression. Also, cognitive appraisal, an adaptive emotion regulation strategy, was associated to rumination before the MBSR program but became related to mindfulness and well-being measures after the program. Community analysis revealed a strong topological association between mindfulness, compassion, and emotional regulation, which supports the key role of compassion in mindfulness training. These results highlight the importance of exploring psychological changes from a network perspective and support the conceptual advantage of considering the interconnectedness of psychological constructs in terms of a 'psychonectome' as it may reveal ways of functioning that cannot be analyzed through conventional analytic methods.

Attentional biases in dysphoria when happy and sad faces are simultaneously presented.

BACKGROUND AND OBJECTIVE: Difficulties to engage attention to positive stimuli and to disengage attention from negative stimuli are typically found in depression. Yet, most of the evidence supporting these attentional biases comes from experimental paradigms in which emotional information (e.g., happy or sad faces) is simultaneously presented with neutral information. Few studies have explored attentional biases when emotional stimuli of different valence are presented simultaneously. The aim of the present study was to assess visual scan patterns of non-dysphoric and dysphoric participants when emotional information is presented simultaneously. METHOD: Using an eye-tracker methodology, the gradient relation between attentional biases and depression scores as well as differences between groups in their attentional performance were assessed in non-dysphoric participants (N = 84) and dysphoric participants (N = 58). Three different pairs of faces were used: happy-neutral, neutral-sad, and happy-sad. RESULTS: First, we found that simultaneous presentation of emotional information (i.e., happy vs. negative faces) reduces the magnitude of attentional biases towards positive information. Second, we also found a significant negative relation between attentional biases towards positive information and depression scores. Finally, compared to non-dysphoric participants, dysphoric individuals marginally spent less time attending positive information in both happy-neutral and happy-sad trials. LIMITATIONS: The cross-sectional nature of our study does not allow us to make inferences about causality. Further, only one type of simultaneous emotional faces presentation (i.e., happy-sad) was used. CONCLUSIONS: These results support the need for further research on the processing of competing emotional stimuli in depression.

"Puerta giratoria" a la situación sin hogar. Influencia de la salud, consumo de alcohol y padecimiento de sucesos vitales estresantes en el número de episodios en la situación sin hogar / The revolving door to homelessness. The influence of health, alcohol consumption and stressful life events on the number of episodes of homelessness

Objetivos: Analizar la incidencia de diferentes variables en el padecimiento de reiterados episodios en la situación sin hogar. Método: El trabajo se realizó a partir de los datos obtenidos de una muestra representativa de las personas en situación sin hogar en Madrid (España) (n=188). Resultados: El padecimiento de una enfermedad grave o crónica ejerce un efecto en la "puerta giratoria" a la situación sin hogar mediado por una percepción subjetiva muy negativa de la propia salud que, a su vez, se encuentra mediada por el padecimiento de alguna discapacidad. El consumo excesivo de alcohol ejerce un efecto en la "puerta giratoria" a la situación sin hogar mediado por el acceso a tratamiento por problemas derivados de dicho consumo. Padecer una enfermedad grave o crónica correlaciona con tener o haber tenido problemas derivados de un consumo excesivo de alcohol. El padecimiento de múltiples sucesos vitales estresantes ejerce un efecto directo en la "puerta giratoria" a la situación sin hogar. Conclusiones: Para prevenir la "puerta giratoria" a la situación sin hogar hay que eliminar las barreras que dificultan el acceso a los recursos normalizados de salud a las personas en exclusión social, a la vez que implementar programas continuados de apoyo para las personas sin hogar o en riesgo que incluyan prioritariamente cuestiones de salud

Objectives: To analyse the impact of different variables on repeated episodes of homelessness. Method: The study was conducted based on data obtained from a representative sample of homeless people in Madrid (Spain) (n=188). Results: Suffering from a serious or chronic illness has an effect on the revolving door to homelessness, which is mediated by a highly negative subjective perception of the individual's own health, which is in turn mediated by suffering from a disability. Excessive alcohol consumption has an effect on the revolving door to homelessness, mediated by access to treatment for problems caused by alcohol consumption. Suffering from a serious or chronic illness correlates with having problems caused by excessive alcohol consumption. Experiencing multiple stressful life events has a direct effect on the revolving door to homelessness. Conclusions: To prevent the revolving door to homelessness, it is necessary to remove the barriers that hinder access to normal health resources which are experienced by people suffering from social exclusion, while implementing on going support programmes for homeless people or those at risk of homelessness, which primarily deal with health issues

Implementation of a Positive Technology Application in Patients With Eating Disorders: A Pilot Randomized Control Trial.

Background: Positive psychological interventions (PPIs) have been suggested to produce benefits in patients with eating disorders (ED) by improving well-being, which might act as a buffer of the harmful effects caused by the disorder. Best Possible Self (BPS) is a PPI which consists of writing and envisioning a future where everything has turned out in the best possible way. In this regard, positive technology (PT) can be of considerable benefit as it allows to implement specific PPIs that have already shown efficacy. Objective: This study tested the preliminary efficacy of the BPS exercise implemented through a PT application and carried out for 1 month, in improving positive functioning measures, compared to a control condition, in patients with ED. Follow-up effects were also explored at 1 and 3 months later. Methods: This is a pilot randomized controlled trial, with two experimental conditions. Participants were 54 outpatients, who were receiving ongoing specialized treatment in ED services. 29 participants were randomly allocated to the BPS intervention and 25 to the control exercise. The sample was composed mostly by females and the mean age was 27 years. In the intervention group, participants had to write about their BPS. In the control group participants had to write about their daily activities. The exercise was conducted through the Book of Life, which is a PT application that allows users to add multimedia materials to the written content. Measures of future expectations, affect, dispositional optimism, hope and self-efficacy were assessed at different time frames. Results: Findings showed that all participants improved over time and there were no statistically significant differences between conditions on the specific measures. These effects were not influenced by prior levels of ED severity. Within-group effect sizes indicate a greater benefit for the participants in the BPS condition, compared to the control condition, on nearly all the measures. Conclusion: Results indicated that PT produced modest improvements in patients with EDs that are receiving current treatment for ED. More empirical attention is needed to explore the potential benefits of PPIs as supporting tools in the prevention and treatment of EDs. Trial registration: clinicaltrails.gov Identifier: NCT03003910, retrospectively registered December 27, 2016.

The Power of Visualization: Back to the Future for Pain Management in Fibromyalgia Syndrome.

OBJECTIVE: Previous studies have demonstrated the effects of positive psychological factors on pain adjustment. Specifically, optimism has been linked to better physical functioning and less psychological distress. Until recently, these beneficial effects have mostly been examined in correlational studies or laboratory settings. The aim of this study was to test the efficacy of the Best Possible Self intervention using information and communication technologies with fibromyalgia patients. METHODS: Seventy-one patients were randomly allocated to the Best Possible Self intervention or a Daily Activities control condition. The Best Possible Self intervention used an interactive multimedia system with the support of an Internet platform to practice the guided imagery exercise online. RESULTS: Intent-to-treat analyses showed that, compared with the control condition, Best Possible Self patients showed significant improvements in depression, positive affect, and self-efficacy at postintervention. Moreover, at three-month follow-up, patients who received the intervention improved their optimism and negative affect significantly more than participants in the control condition. CONCLUSIONS: This study shows how a technology-supported intervention aimed at augmenting positive affect and promoting positive functioning works in the case of fibromyalgia, expanding the intervention's efficacy data in clinical populations and adding knowledge about the role that positive psychological factors play in pain experience. Moreover, it demonstrates the specific effects of the Best Possible Self intervention in order to incorporate this exercise in pain treatment protocols.

Degradación de tiocianato por hongos aislados de ambientes mineros y evaluación de su capacidad degradativa / The thiocyanate degradation by fungi isolated from mining environments and evaluation of degradative capacity

El Perú es uno de los principales países en la extracción de minerales como el oro, zinc, plomo y estaño. En la producción de oro se utiliza cianuro, el cual es tóxico para el medio ambiente, y que por reacción natural con el azufre se convierte en tiocianato (-SCN). En el presente trabajo se aislan hongos con capacidad de degradar tiocianato procedentes de aguas y suelos de zonas mineras de Junín y Tumbes. Estas cepas se sometieron a ensayos con concentraciones de tiocianato entre 5 y 600 mM. Asimismo, se evaluó la cinética de degradación de tiocianato en medio Kwon partiendo de 1,2 g.L-1 de KSCN y luego se realizó la identificación morfológica. De un total de 58 mohos aislados, obtuvimos 4 mohos con excelentes capacidades de degradar tiocianato y que pueden ser utilizados en biorremediación. La capacidad degradativa de estas cepas fue en promedio 10,05 mg.L-1 de -SCN con una velocidad de 28,77 mg.L-1.h-1. Dos cepas fueron identificadas fenotípica y molecularmente como Fusarium trincictum usando el marcador ITS del gen rDNA.

Peru is one of the principal countries in mining extraction of minerals like gold, zinc, plumb and tin. Cyanide is used in gold production this compound is very toxic especially for environment, by nature reaction with sulfur it converts into thiocyanate (-SCN). In this paper, we isolate -SCN degrading fungus from Junin and Tumbes mining zones. Strains were assayed on 5 to 600 mM -SCN concentration, at least thiocyanate degrading kinetic was assayed at 1.2 g.L-1 of KSCN initial concentration, then the best strains had been morphological, biochemical and molecular identified using ITS RNA molecular marker. From 58 isolated fungus we found 4 unparfait funguses with a great thiocyanate degrading capacity those strains could be used for bioremediation processes. Thiocyanate degrading capacity of these strains was 50 g.L-1 on plate into 72 hours and their average capacity was 10.05 mg.L-1 -SCN with an standard velocity of -SCN degradation of 28.77 mg.L-1.h-1. Two strains were molecular identified as Fusarium trincictum by using ITS rDNA gene.

Biodiversidad y endemismo de los caracoles terrestres Megalobulimusy Systrophia en la Amazonia occidental / Biodiversity and endemism of the western Amazonia land snails Megalobulimus and Systrophia

En este trabajo realizamos un estudio biogeográfico de dos géneros de caracoles terrestres amazónicos, Megalobulimus (Strophocheilidae) y Systrophia (Scolodontidae). Se utilizaron individuos colectados en diversas localidades de la Amazonia peruana así como información bibliográfica. Se utilizaron los marcadores moleculares 5.8S-ITS2-28S rRNA y 16S rRNA para reconstruir filogenias y obtener hipótesis sobre las relaciones evolutivas entre los géneros amazónicos y otras especies de distribución global. La filogenia nuclear permitió determinar la posición evolutiva de ambos géneros y la filogenia mitocondrial permitió la diferenciación de las especies a nivel intragenérico. Megalobulimus formó parte del clado no-achatinoideo en la filogenia de los gastrópodos Stylommatophora, como lo esperado, pero no pudo ser demostrada su cercanía a la familia Acavidae, mientras que Systrophia quedó fuera de los dos clados establecidos, formando uno basal dentro de los Stylommatophora. El gen mitocondrial 16S rRNA permitió diferenciar a las especies de Megalobulimus, actuando como código de barras de ADN de estos caracoles comestibles. El análisis de distribución geográfica reveló varios endemismos para la Amazonia peruana para especies de ambos géneros, resaltando las unidades biogeográficas de Chanchamayo e Inambari.

In this work we performed a biogeographic study of two genera of Amazonian land snails, Megalobulimus (Strophocheilidae) and Systrophia (Scolodontidae). We used samples from different regions of the Peruvian Amazon, as well as bibliographic information. We analyzed both nuclear (5.8S-ITS2-28S rRNA) and mitochondrial (16S rRNA) genes to reconstruct phylogenies and obtain hypotheses concerning the evolutionary relationships among Amazonian genera and other species with global distribution. The nuclear phylogeny allowed us to determine the evolutionary position of both genera, and the mitochondrial phylogeny permitted the differentiation of species at the intrageneric level. We found that Megalobulimus clustered with the non-achatinoid clade within Stylommatophora, as expected, but its relationship to family Acavidae could not be demonstrated. Systrophiadid not cluster with any of the two established clades, but formed a basal one within Stylommatophora. The mitochondrial gene 16S rRNA allowed us to differentiate Megalobulimus species, and performed well for DNA barcoding of these edible snails. Biogeographical analysis revealed several endemic species in the Peruvian Amazon within both genera, highlighting the Chanchamayo and Inambari biogeographic units.

Identificación de Yarrowia lipolytica (Ascomycota: Hemiascomycetes) como contaminante en la obtención de amplificados del gen 28S rRNA de moluscos / Identification of Yarrowia lipolytica (Ascomycota: Hemiascomycetes) as a contaminant in obtaining amplified 28S rRNA gene of mollusks

En el presente trabajo se identifica una secuencia de DNA no esperada proveniente de los amplificados del gen 28S rRNA de moluscos terrestres. Las extracciones de DNA se realizaron del tejido del pie de caracoles terrestres por el método del CTAB modificado. Las PCRs fueron llevadas a cabo con primers universales para el gen COI e iniciadores diseñados para moluscos, para el marcador 16S rRNA, 28S rRNA y la región ITS-2. Los tamaños aproximados de las bandas de los amplificados de moluscos fueron de 706 pb para el COI, 330pb para el 16S rRNA, 900 pb para el ITS-2 y 583 pb para el 28S rRNA; un amplificado del último marcador fuede una longitud inesperada, ~340 pb. Las secuencias de DNA fueron comparadas con la base de datos del GenBank mediante el programa BLASTn y la muestra con la banda de tamaño inesperado resultó en un 100% de identidad y cobertura del 99% con el gen 26S rRNA de la levadura Yarrowia lipolytica. El análisis filogenético con Neighbour-Joining y los valores de divergencia confirmaron la identificación, proporcionando resultados que apoyan la ubicación taxonómica de la especie dentro del clado de los Hemiascomycetes.

In this paper we identify an unexpected DNA sequence from the amplicons of 28S rRNA gene of terrestrial mollusks. DNA extractions were performed from foot tissues of land snails using a modified CTAB protocol. PCRs were carried out with universal primers for COI gene and oligonucleotides designed for molluscs, for the markers 16S rRNA, 28S rRNA, and ITS-2. Amplified lengths were 706 pb for COI, 330 pb for 16S rRNA, 900 pbfor ITS-2, and 583 pb for 28S rRNA. One amplicon of the last marker was of an unexpected length, ~340 pb. DNA sequences were compared in the GenBank database through the BLASTn program and the sample, with the unexpected length, resulted in 100% identity and 99% query coverage with 26S rRNA gene of the yeast Yarrowia lipolytica. Phylogenetic analysis with Neighbour-Joining and the divergence values confirmed the identification, providing results that support the taxonomic placement of the species within the Hemiascomycetes clade.

Posición evolutiva de caracoles terrestres peruanos (Orthalicidae) entre los Stylommatophora (Mollusca: Gastropoda) / Evolutionary position of Peruvian land snails (Orthalicidae) among Stylommatophora (Mollusca: Gastropoda)

Los géneros Bostryx y Scutalus (Orthalicidae: Bulimulinae) son endémicos de América del Sur y están principalmente distribuidos en la vertiente occidental de los Andes del Perú. El objetivo del presente trabajo fue evaluar su posición evolutiva dentro de los gastrópodos Stylommatophora basada en el marcador mitocondrial 16S rRNA. Fueron obtenidas cuatro secuencias las que, junto con 28 de otros Stylommatophora disponibles en el GenBank, fueron alineadas con ClustalX. La reconstrucción filogenética se realizó mediante los métodos de Neighbor-Joining, Máxima Parsimonia, Máxima Verosimilitud e Inferencia Bayesiana. El alineamiento resultó en 371 sitios, con presencia de indels. Los dos géneros de la Familia Orthalicidae por primera vez incluidos en una filogenia molecular (Bostryx y Scutalus), formaron un grupo monofilético con otro miembro de la superfamilia Orthalicoidea (Placostylus), tal como lo obtenido con marcadores nucleares. Se discute también su relación evolutiva con otros caracoles terrestres.

The genera Bostryx and Scutalus (Orthalicidae: Bulimulinae) are endemics from South America. They are mainly distributed on the western slopes of the Peruvian Andes. The goal of the present work was to assess their evolutionary position among the stylommatophoran gastropods based on the 16S rRNA mitochondrial marker. Four sequences were obtained, and along with 28 sequences of other Stylommatophora retrieved from the GenBank, were aligned with ClustalX. The phylogenetic reconstruction was carried out using the methods of Neighbor-Joining, Maximum Parsimony, Maximum Likelihood and Bayesian inference. The multiple sequence alignment had 371 sites, with indels. The two genera of the family Orthalicidae for the first time included in a molecular phylogeny (Bostryx and Scutalus), formed a monophyletic group along with another member of the superfamily Orthalicoidea (Placostylus), result that is comparable with that obtained with nuclear markers. Their evolutionary relationship with other land snails is also discussed.

Identificación molecular de Pichia guillermondii aislada de aguas ácidas de minas en el Perú y su resistencia a metales pesados / Molecular identification of Pichia guillermondii isolated from mine water acidic of Peru and its resistance to heavy metals

Las aguas ácidas de minas tienen una considerable diversidad de microorganismos eucariontes, entre ellos hongos y protistas; en particular, poco se conoce sobre la diversidad de levaduras en drenajes ácidos de minas peruanas. En el presente estudio se aisló y caracterizó la levadura 1MA9, mediante la amplificación y secuenciación del LSU D1/D2 del gen rRNA 26S. La cepa 1MA9 se identificó molecularmente como Pichia guillermondi, ésta presentó una resistencia alta a Mn2+ (>400 mM), intermedia a iones Zn2+ y Co2+ (400—600 mM), pero fue sensible a iones Cu2+. Este trabajo representa el primer reporte de levaduras en ambientes acuáticos ácidos proveniente de minas peruanas.

Microbe eukaryotes like fungi and protista are common in the drainage of mines. Few information is known on microbial diversity of acid drainages of Peruvian mines. In this work we isolated and characterized the 1M9 yeast. We utilized LSU D1/D2 of the 26S rRNA gene sequence phylogenetic analyses to characterize the diversity the yeast 1MA9 isolated. The strain 1MA9 was closely related to the Pichia guilliermondii. The yeast showed high resistance to Mn2+ (>400 mM), intermediate to ions Zn2+ and Co2+ (400—600 mM), but sensible to ions Cu2+. This work provides the first data on yeasts from an aquatic acid environment of Peruvian mines.