First report of mixed Trypanosoma cruzi discrete typing units infection in Triatoma phyllosoma in the peri-urban environment of Oaxaca, Mexico.

BACKGROUND: Chagas disease, a zoonosis transmitted mainly by hematophagous insects of the subfamily Triatominae, is caused by Trypanosoma cruzi, classified into six discrete typing units (DTUs: TcI-TcVI and Tcbat). METHODS: Insect vectors were collected from 84 human dwellings in the municipality of Santo Domingo Tehuantepec, Oaxaca, Mexico; 4.76% were infested. DTUs were determined using conventional and nested PCR. RESULTS: The infection rate was 43.6%. All insects were infected with TcI while one specimen showed mixed infection with TcII. CONCLUSIONS: This is the first report of T. cruzi mixed infection in Triatoma phyllosoma, its main vector in the study region.

Effects of vitamin D levels during pregnancy on prematurity: a systematic review protocol.

INTRODUCTION: Prematurity is an urgent public health problem worldwide. Recent studies associate maternal hypovitaminosis D during pregnancy with an increased risk of prematurity. However, the evidence on this association remains inconclusive, and there is lack of consensus in the literature. The exact mechanism by which low vitamin D levels may increase the risk of preterm birth is not yet fully understood. Nevertheless, it is known that vitamin D may play a role in maintaining a healthy pregnancy by regulating inflammation and immunomodulation by acting on the maternal and fetal immune systems. Inflammation and immune dysregulation are both associated with preterm birth, and low vitamin D levels may exacerbate these processes. The results of this review may have important implications for clinical practice and public health policy, particularly regarding vitamin D supplementation during pregnancy. METHODS AND ANALYSIS: A systematic review of the literature will be conducted. The search will be performed in electronic databases: CINAHL; MEDLINE; Cochrane Central Register of Controlled Trials; Cochrane Library; Academic Search Complete; Information Science and Technology Abstracts; MedicLatina; SCOPUS; PubMed; and Google Scholar, with the chronological range of January 2018 to November 2022. The search strategy will include the following Medical Subject Headings or similar terms: 'Vitamin D'; '25-hydroxyvitamin D'; 'Hypovitaminosis D'; 'Pregnancy'; 'Pregnant women'; 'Expectant mother'; 'Prematurity'; 'Premature birth'; 'Premature delivery'; 'Preterm birth'; and 'Preterm labour'. This review will include quantitative primary studies, both experimental (clinical trials) and observational (cohort, cross-sectional, and case-control). The quality of each selected study and the results obtained will be assessed by two reviewers separately, using the Cochrane risk of bias tool for evaluating randomised clinical trials or the Newcastle Ottawa Scale for non-randomised studies, following the respective checklist. In case of disagreement, a third reviewer will be consulted. ETHICS AND DISSEMINATION: This study does not involve human subjects and therefore does not require ethics approval. The results will be disseminated through publication in a peer-reviewed scientific journal and through conference presentations. All changes made to the protocol will be registered in PROSPERO, with information on the nature and justification for the changes made. PROSPERO REGISTRATION NUMBER: CRD42022303901.

First report of mixed Trypanosoma cruzi discrete typing units infection in Triatoma phyllosoma in the peri-urban environment of Oaxaca, Mexico

ABSTRACT Background: Chagas disease, a zoonosis transmitted mainly by hematophagous insects of the subfamily Triatominae, is caused by Trypanosoma cruzi, classified into six discrete typing units (DTUs: TcI-TcVI and Tcbat). Methods: Insect vectors were collected from 84 human dwellings in the municipality of Santo Domingo Tehuantepec, Oaxaca, Mexico; 4.76% were infested. DTUs were determined using conventional and nested PCR. Results: The infection rate was 43.6%. All insects were infected with TcI while one specimen showed mixed infection with TcII. Conclusions: This is the first report of T. cruzi mixed infection in Triatoma phyllosoma, its main vector in the study region.

Diverse roles of mtDNA in schizophrenia: Implications in its pathophysiology and as biomarker for cognitive impairment.

Schizophrenia (SZ) is a mental disorder characterized by neurocognitive dysfunctions and a reduction in occupational and social functioning. Several studies have provided evidence for mitochondrial dysfunction in the pathophysiology of SZ. In this sense, it is known that the addition of genetic variations in mitochondrial DNA (mtDNA) impairs oxidative phosphorylation of enzymatic complexes in mitochondria, resulting in ATP depletion and subsequent enhancement of reactive oxygen species; this is associated with cellular degeneration and apoptosis observed in some neuropsychiatric disorders. As a consequence of mitochondrial dysfunction, an increase in circulating cell-free mtDNA fragments can occur, which has been observed in individuals with SZ. Moreover, due to the bacterial origin of mitochondria, these cell-free mtDNA fragments in blood plasma may induce inflammatory and immunogenic responses, especially when their release is enhanced in specific disease conditions. However, the exact mechanism by which mtDNA could be released into blood plasma is not yet clear. Therefore, the aims of this review article were to discuss the participation of mtDNA genetic variations in physiopathologic mechanisms of SZ, and to determine the status of the disease and the possible ensuing changes over time by using circulating cell-free mtDNA fragments as a biomarker.

High polygenic burden is associated with blood DNA methylation changes in individuals with suicidal behavior.

Suicidal behavior is result of the interaction of several contributors, including genetic and environmental factors. The integration of approaches considering the polygenic component of suicidal behavior, such as polygenic risk scores (PRS) and DNA methylation is promising for improving our understanding of the complex interplay between genetic and environmental factors in this behavior. The aim of this study was the evaluation of DNA methylation differences between individuals with high and low genetic burden for suicidality. The present study was divided into two phases. In the first phase, genotyping with the Psycharray chip was performed in a discovery sample of 568 Mexican individuals, of which 149 had suicidal behavior (64 individuals with suicidal ideation, 50 with suicide attempt and 35 with completed suicide). Then, a PRS analysis based on summary statistics from the Psychiatric Genomic Consortium was performed in the discovery sample. In a second phase, we evaluated DNA methylation differences between individuals with high and low genetic burden for suicidality in a sub-sample of the discovery sample (target sample) of 94 subjects. We identified 153 differentially methylated sites between individuals with low and high-PRS. Among genes mapped to differentially methylated sites, we found genes involved in neurodevelopment (CHD7, RFX4, KCNA1, PLCB1, PITX1, NUMBL) and ATP binding (KIF7, NUBP2, KIF6, ATP8B1, ATP11A, CLCN7, MYLK, MAP2K5). Our results suggest that genetic variants might increase the predisposition to epigenetic variations in genes involved in neurodevelopment. This study highlights the possible implication of polygenic burden in the alteration of epigenetic changes in suicidal behavior.

Association between mitochondrial DNA and cognitive impairment in schizophrenia: study protocol for a Mexican population.

BACKGROUND: Circulating cell-free mitochondrial DNA (cf-mtDNA) fragments in blood plasma have been reported in patients with schizophrenia (SZ). Although the relationship of cf-mtDNA to the cognitive status of patients with SZ has not yet been explored, it is known that cognitive impairment in SZ compromises the functional and social capacity of these patients and diminishes their quality of life. In this sense, the assessment of the severity of cognitive impairment in a Mexican population with SZ and its association with cf-mtDNA levels in blood plasma may provide the possibility of using cf-mtDNA as a biomarker to determine the status of the disease and the possible ensuing changes over time. METHODS: Subjects for a case-control study will be recruited. cf-mtDNA obtained from blood plasma will be quantified by real-time polymerase chain reaction, using melting curve technology with SYBR green as amplification marker. Patients with SZ will be grouped into those with severe, mild, and no cognitive impairment according to Montreal Cognitive Assessment scale scores, to determine differences between cognitive performance and cf-mtDNA levels in blood plasma. ETHICS AND COMMUNICATION: This study has been approved by the ethics and investigation committees of the High Specialty Regional Hospital of Mental Health (Hospital Regional de Alta Especialidad de Salud Mental); project No. HRAESM/DG/RP/1128/2018. We plan to communicate our research findings in scientific conferences and in peer-reviewed journals. CONCLUSION: It is known that cognitive dysfunction provokes negative effects in an SZ patient´s life. This project aims to provide better knowledge about the role of cf-mtDNA in the pathogenesis of cognitive impairment in SZ, as an attempt to achieve improvements to the existing treatments, thereby helping to prevent major cognitive deterioration.

Quando a brincadeira vira coisa séria: dos mitos e (in)verdades sobre as relações entre jogos digitais, cultura e consumo / When play becomes a serious matter: myths and (un)truths about relationships between digital games, culture and consumption / Cuando el juego se pone serio: de mitos, verdades y mentiras sobre las relaciones entre juegos digitales, cultura y consumo

Resumo Este ensaio discute as relações entre jogos digitais, cultura e consumo, abordando as principais ambiguidades e contradições existentes no movimento de popularização dos videogames. Para alcançar essa meta, além do diálogo com a literatura, foram aludidas pesquisas estatísticas que apresentam informações atinentes às indústrias do setor e aos (perfis dos) jogadores. Inferiu-se que essa difusão é subsidiada por práticas culturais ambivalentes, que pendem entre a ilegalidade e a luta contra a desigualdade de acesso a esse e outros bens culturais.

Abstract This essay discusses about relationship between digital games, culture and consumption, adressing the major ambiguities and contradictions in the movement of popularization of video games. To achieve this goal, addition to dialogue with the literature, were alluded to statistical surveys that have information pertaining to industries of the branch and players (profile). Inferred that this diffusion is subsidized by ambivalent cultural practices, which hang between the illegality and the fight against inequality of access to this and other cultural goods.

Resumen Este ensayo analiza la relación entre los videojuegos, la cultura y el consumo, y aborda las ambigüedades y contradicciones principales que existen en el movimiento de popularización de los videojuegos. Para lograr este objetivo, además de un diálogo con la literatura, se hizo alusión a las búsquedas estadísticas que poseen información relacionada con las industrias del sector y con los (perfiles de los) jugadores. Se concluyó que esta difusión está subvencionada por ambivalentes prácticas culturales, que cuelgan entre la ilegalidad y la lucha contra la desigualdad de acceso a éste y otros bienes culturales.

Maturational changes in the interdependencies between cortical brain areas of neonates during sleep.

This work aims at assessing the maturational changes in the interdependence between the activities of different cortical areas in neonates during active sleep (AS) and quiet sleep (QS). Eight electroencephalography (EEG) channels were recorded in 3 groups of neonates of increasing postmenstrual age. The average linear (AVL) and average nonlinear (AVN) interdependencies of each electrode region with the remaining ones were calculated using the coherence function and a recently developed index of nonlinear coupling between 2 signals in their state spaces, respectively. In theta band, AVL increased with neonate's age for central and temporal regions during QS. In beta band, AVL increased for most cortical regions during QS and a parallel decrease of AVL with neonate's age was found during AS. For all regions, beta AVL was greater in AS than in QS in preterm neonates but the reverse happened in older term neonates. Contrarily to AVL, AVN decreased with age during QS for most cortical regions. Surrogate data test showed that the interdependencies were nonlinear in preterm and younger term neonates but in older term both linear and nonlinear interdependencies coexisted. It is concluded that neonatal maturation is associated with changes in the magnitude and character of the EEG interdependencies during sleep.

Topography of EEG complexity in human neonates: effect of the postmenstrual age and the sleep state.

The topography of the EEG of human neonates is studied in terms of its power spectral density and its estimated complexity as a function of both the postmenstrual age (PMA) and the sleep state. The monopolar EEGs of three groups of seven neonates (preterm, term and older term) were recorded during active (AS) and quiet sleep (QS) from electrodes Fp1, Fp2, T3, T4, C3, C4, O1 and O2. The existence of changes between groups and sleep states in the power of delta, theta, alpha and beta bands and in the dimensional complexity of these electrodes was tested. Additionally, the nonlinearity of the EEG in each electrode and situation was analyzed. The results of the spectral measures show an increment of the power in the low frequency bands from AS to QS and with the PMA, which can be mainly traced on central and temporal electrodes. This change is shown as well by the dimensional complexity, which also presents the greatest differences in the central derivations. Moreover, the signals show evidence of nonlinearity in almost all the groups and situations, although a dynamic change from nonlinear to linear character is apparent in the central electrodes with increased PMA. As a result, it is concluded that nonlinear analysis methods provide a clear portrait of the integrated brain activity that complements the information of spectral analysis in the characterization of the brain development and the sleep states in neonates.

Comparing generalized and phase synchronization in cardiovascular and cardiorespiratory signals.

We made use of multivariate nonlinear analysis methods to study the interdependence between the cardiac interval variability and both the respiratory activity and the systolic pressure in rats. The study was carried out in basal conditions and after the application of different drugs affecting the cardiovascular system. The results showed that there are changes both in the extent and in the directionality of such interdependences because of the drugs. The inhibition of the NO and the parasympathetic blockade changed the cardiovascular coordination, with the latter one also modifying the interdependence between the cardiac interval and the respiratory signal. This suggests that the nonlinear approach might be very helpful to explore the interaction between subsystems of the cardiovascular control system.