Uncovering novel bacterial and archaeal diversity: genomic insights from metagenome-assembled genomes in Cuatro Cienegas, Coahuila.

A comprehensive study was conducted in the Cuatro Ciénegas Basin (CCB) in Coahuila, Mexico, which is known for its diversity of microorganisms and unique physicochemical properties. The study focused on the "Archaean Domes" (AD) site in the CCB, which is characterized by an abundance of hypersaline, non-lithifying microbial mats. In AD, we analyzed the small domes and circular structures using metagenome assembly genomes (MAGs) with the aim of expanding our understanding of the prokaryotic tree of life by uncovering previously unreported lineages, as well as analyzing the diversity of bacteria and archaea in the CCB. A total of 325 MAGs were identified, including 48 Archaea and 277 Bacteria. Remarkably, 22 archaea and 104 bacteria could not be classified even at the genus level, highlighting the remarkable novel diversity of the CCB. Besides, AD site exhibited significant diversity at the phylum level, with Proteobacteria being the most abundant, followed by Desulfobacteria, Spirochaetes, Bacteroidetes, Nanoarchaeota, Halobacteriota, Cyanobacteria, Planctomycetota, Verrucomicrobiota, Actinomycetes and Chloroflexi. In Archaea, the monophyletic groups of MAGs belonged to the Archaeoglobi, Aenigmarchaeota, Candidate Nanoarchaeota, and Halobacteriota. Among Bacteria, monophyletic groups were also identified, including Spirochaetes, Proteobacteria, Planctomycetes, Actinobacteria, Verrucomicrobia, Bacteroidetes, Candidate Bipolaricaulota, Desulfobacteria, and Cyanobacteria. These monophyletic groups were possibly influenced by geographic isolation, as well as the extreme and fluctuating environmental conditions in the pond AD, such as stoichiometric imbalance of C:N:P of 122:42:1, fluctuating pH (5-9.8) and high salinity (5.28% to saturation).

A Metagenomic Time-Series Approach to Assess the Ecological Stability of Microbial Mats in a Seasonally Fluctuating Environment.

Microbial mats are complex ecological assemblages that have been present in the rock record since the Precambrian and can still be found in extant marginalized environments. These structures are considered highly stable ecosystems. In this study, we evaluate the ecological stability of dome-forming microbial mats in a modern, water-level fluctuating, hypersaline pond located in the Cuatro Ciénegas Basin, Mexico. We conducted metagenomic sampling of the site from 2016 to 2019 and detected 2250 genera of Bacteria and Archaea, with only <20 belonging to the abundant taxa (>1%). The microbial community was dominated by Proteobacteria, Euryarchaeota, Bacteroidetes, Firmicutes, and Cyanobacteria, and was compositionally sensitive to disturbances, leading to high taxonomic replacement even at the phylum level, with a significant increase in Archaea from [Formula: see text]1-4% to [Formula: see text]33% throughout the 2016-2019 study period. Although a core community represented most of the microbial community (>75%), relative abundances shifted significantly between samples, as demonstrated by changes in the abundance of Coleofasciculus from 10.2% in 2017 to 0.05% in 2019. Although functional differences between seasons were subtle, co-occurrence networks suggest differential ecological interactions between the seasons, with the addition of a new module during the rainy season and the potential shift in hub taxa. Functional composition was slightly more similar between samples, but basic processes such as carbohydrate, amino acid, and nucleic acid metabolisms were widely distributed among samples. Major carbon fixation processes included sulfur oxidation, nitrogen fixation, and photosynthesis (both oxygenic and anoxygenic), as well as the Wood-Ljundgahl and Calvin cycles.

Diversity of an uncommon elastic hypersaline microbial mat along a small-scale transect.

We evaluated the microbial diversity and metabolome profile of an uncommon hypersaline elastic microbial mat from Cuatro Ciénegas Basin (CCB) in the Chihuahuan Desert of Coahuila, México. We collected ten samples on a small scale transect (1.5-m) and described its microbial diversity through NGS-based ITS and 16S rDNA gene sequencing. A very low number of taxa comprised a considerable proportion of the mat and were shared across all sampling points, whereas the rare biosphere was more phylogenetically diverse (Faith's Phylogenetic Diversity (FPD) index) and phylogenetically disperse (using a null model distribution of Phylogenetic Species Clustering (nmdPSC)) than the abundant (high read count) taxa for both analyzed libraries. We also found a distinctive metabolome profile for each sample and were able to tentatively annotate several classes of compounds with relevant biological properties.

MicNet toolbox: Visualizing and unraveling a microbial network.

Applications of network theory to microbial ecology are an emerging and promising approach to understanding both global and local patterns in the structure and interplay of these microbial communities. In this paper, we present an open-source python toolbox which consists of two modules: on one hand, we introduce a visualization module that incorporates the use of UMAP, a dimensionality reduction technique that focuses on local patterns, and HDBSCAN, a clustering technique based on density; on the other hand, we have included a module that runs an enhanced version of the SparCC code, sustaining larger datasets than before, and we couple the resulting networks with network theory analyses to describe the resulting co-occurrence networks, including several novel analyses, such as structural balance metrics and a proposal to discover the underlying topology of a co-occurrence network. We validated the proposed toolbox on 1) a simple and well described biological network of kombucha, consisting of 48 ASVs, and 2) we validate the improvements of our new version of SparCC. Finally, we showcase the use of the MicNet toolbox on a large dataset from Archean Domes, consisting of more than 2,000 ASVs. Our toolbox is freely available as a github repository (https://github.com/Labevo/MicNetToolbox), and it is accompanied by a web dashboard (http://micnetapplb-1212130533.us-east-1.elb.amazonaws.com) that can be used in a simple and straightforward manner with relative abundance data. This easy-to-use implementation is aimed to microbial ecologists with little to no experience in programming, while the most experienced bioinformatics will also be able to manipulate the source code's functions with ease.

Recent Differentiation of Aquatic Bacterial Communities in a Hydrological System in the Cuatro Ciénegas Basin, After a Natural Perturbation.

Pozas Rojas is a hydrological system comprising nine isolated shallow ponds and a deep lagoon, which were temporally merged in 2010 by increased rainfall due to a tropical cyclone. In this work, we assess which components, biotic interactions, or environment filtering effects, drive the assembly of microbial communities after a natural perturbation. Arsenic, pH, and temperature are among the most significant environmental variables between each pond, clustering the samples in two main groups, whereas microbial composition is diverse and unique to each site, with no core at the operational taxonomic unit level and only 150 core genera when studied at the genus level. Los Hundidos lagoon has the most differentiated community, which is highly similar to the epipelagic Mediterranean Sea communities. On the other hand, the shallow ponds at the Pozas Rojas system resemble more to epicontinental hydrological systems, such as some cold rivers of the world and the phreatic mantle from Iowa. Overall, despite being a sole of water body 2 years prior to the sampling, interspecific interactions, rather than environmental selection, seem to play a more important role in Pozas Rojas, bolstered by founder effects on each poza and subsequent isolation of each water body.

Deep Brain Stimulation for Refractory Temporal Lobe Epilepsy. Current Status and Future Trends.

A comparative analysis of the targets for deep brain stimulation (DBS) to treat refractory temporal lobe epilepsy and the rationale for its use is presented, with an emphasis on the latency to obtain the significant antiepileptic effect and the long-term seizure control. The analysis includes consideration of surgical techniques currently used to optimize antiseizure effects and decrease surgical risks. Seizure control is similar for programed DBS and DBS responsive to abnormal cortical or subcortical electroencephalogram (EEG) activity. There is no difference in the long-term seizure control between programmed and responsive and intermittent or continuous DBS. However, intermittent programed DBS may have a significant antiseizure effect starting in the first month when applied to a non-sclerotic tissue such as the parahippocampal cortex. DBS induces no neuropsychological deterioration.

What Is the Role of the Inflammation in the Pathogenesis of Heart Failure?

PURPOSE OF REVIEW: In heart failure, whether it is associated with reduced or preserved ejection fraction, the immune system is activated and contributes to heart remodeling and impaired function. RECENT FINDINGS: Studies indicate that cells of the immune system not only play a role in the pathology but are also critical regulators of heart function. Knowledge about the role of the immune system driving heart failure will lead to the development of new targets to this system, particularly in those patients that, despite the apparent wellness, relapse and worsen. In this review, we will address the diverse mechanisms that trigger inflammation and their impact on heart failure progression.

Isochromosome 17q, a Rare Chromosomal Abnormality in a Female Patient with Pancytopenia.

OBJECTIVES: Myelodysplastic syndromes present with a range of cytogenetic abnormalities that are used to guide diagnosis and management of the disease. Herein, we present the case of a 72-year-old female patient who presented with pancytopenia. Peripheral blood showed Hb 9.0 g/dl, neutrophils less than 1800/mm3, and platelets less than 100,000/mm3. Bone marrow showed erythroid hyperplasia, megaloblastic changes, dyserythropoiesis, multinuclearity, nuclear bridges, nuclear budding, atypical mitoses, and ring sideroblasts. Also, CD34 and CD117 as well as myeloperoxidase positive populations were present. On this basis, a diagnosis of myelodysplastic syndrome was rendered. Chromosome studies showed an abnormal female karyotype with an isochromosome 17q as well as deletion 20q in 17 of the 20 metaphase cells examined. The remaining three cells were cytogenetically normal. Molecular cytogenetic studies using a TP53-specific probe showed only one TP53 signal in 87% of the nuclei examined. An i(17q) as a sole cytogenetic aberration is rare among both MDS and myeloid malignancies in general, but is functionally similar to aberrations of 17p that lead to loss of TP53. This case provides further insight into the spectrum of cytogenetic abnormalities present in MDS.

Alterations of 5-HT1A receptor-induced G-protein functional activation and relationship to memory deficits in patients with pharmacoresistant temporal lobe epilepsy.

The 5-hydroxytryptamine-1A (5-HT1A) receptors are known to be involved in the inhibition of seizures in epilepsy. Moreover, studies propose a role for the 5-HT1A receptor in memory function; it is believed that the higher density of this receptor in the hippocampus plays an important role in its regulation. Positron emission tomography (PET) studies in patients with mesial temporal lobe epilepsy (mTLE) have demonstrated that a decrease in 5-HT1A receptor binding in temporal regions may play a role in memory impairment. The evidences lead us to speculate whether this decrease in receptor binding is associated with a reduced receptor number or if the functionality of the 5-HT1A receptor-induced G-protein activation and/or the second messenger cascade is modified. The purpose of the present study is to determine 5-HT1A receptor-induced G-protein functional activation by 8-OH-DPAT-stimulated [(35)S]GTPγS binding assay in hippocampal tissue of surgical patients with mTLE. We correlate functional activity with epilepsy history and neuropsychological assessment of memory. We found that maximum functional activation stimulation values (Emax) of [(35)S]GTPγS binding were significantly increased in mTLE group when compared to autopsy samples. Furthermore, significant correlations were found: (1) positive coefficients between the Emax with the age of patient and frequency of seizures; (2) negative coefficients between the Emax and working memory, immediate recall and delayed recall memory tasks. Our data suggest that the epileptic hippocampus of patients with mTLE presents an increase in 5-HT1A receptor-induced G-protein functional activation, and that this altered activity is related to age and seizure frequency, as well as to memory consolidation deficit.

Effects of rTMS on Parkinson's disease: a longitudinal fMRI study.

Parkinson's disease is a movement disorder whose principal symptoms are tremor, rigidity, bradykinesia and postural instability. Initially, drugs like L: -dopa or dopaminergic agonists are able to control these symptoms, but with the progress of the disease these drugs become less effective. Previous studies have reported that repetitive transcranial magnetic stimulation (rTMS) can improve these motor symptoms. The objective of this study was to investigate the neural mechanisms through which 25 Hz rTMS may improve motor symptoms in Parkinson's disease. In a double-blind placebo-controlled study, we evaluated the effects of 25 Hz. rTMS in 10 Parkinson's disease patients. Fifteen rTMS sessions were performed over the primary cortex on both hemispheres (one after the other) during a 12-week period. The patients were studied using functional magnetic resonance imaging during performance of a simple tapping and a complex tapping task, 1 week before the administration of the first rTMS session and just after the last session. rTMS improved bradykinesia, while functional magnetic resonance imaging showed different cortical patterns in prefrontal cortex when patients performed the complex tapping test. Furthermore, the improvement in bradykinesia is associated with caudate nucleus activity increases in simple tapping. Finally, we observed a relative change in functional connectivity between the prefrontal areas and the supplementary motor area after rTMS. These results show a potential beneficial effect of repetitive transcranial magnetic stimulation on bradykinesia in Parkinson's disease which is substantiated by neural changes observed in functional magnetic resonance imaging.

Preliminary study in patients with obsessive-compulsive disorder treated with electrical stimulation in the inferior thalamic peduncle.

OBJECTIVE: Deep brain stimulation has been used in the treatment of refractory obsessive-compulsive disorder (OCD). Our principal objective was to determine the safety and effectiveness of deep brain stimulation of the inferior thalamic peduncle in the treatment of refractory OCD. METHODS: An open protocol was performed from March 2003 to April 2007 in 5 patients with OCD refractory to conventional treatments. Bilateral stereotactic implantation of tetrapolar electrodes was aimed at the inferior thalamic peduncle and corroborated by electrophysiological responses and magnetic resonance imaging. All patients were off stimulation for 1 month after implantation. In the on-stimulation period, parameters were set at 5 V, 450 microseconds, 130 Hz in bipolar and continuous mode. Clinical changes were evaluated every 3 months for 12 months by means of the Yale-Brown Obsessive Compulsive Scale and the Global Assessment of Functioning scale. Statistical significance was assessed by the Friedman and Wilcoxon tests. RESULTS: The mean Yale-Brown Obsessive Compulsive Scale score decreased from 35 to 17.8 (P < 0.001), and the mean Global Assessment of Functioning scale score improved from 20% to 70% (P < 0.0001). The neuropsychological battery did not show significant changes, and there were no side effects related to electrical stimulation in the chronic period. CONCLUSION: We conclude that inferior thalamic peduncle stimulation is a safe procedure and may be an effective alternative in the treatment of those OCD cases refractory to conventional treatments.

Neuromodulation of epileptic foci in patients with non-lesional refractory motor epilepsy.

We report two cases of chronic therapeutic stimulation of epileptic foci localized in motor areas. Case 1 is an adolescent with supplementary motor area seizures whose intracranial recordings showed a right SMA focus. Case 2 is a female teenager with primary motor seizures originating in the right motor cortex in the hand area as shown by her intracranial recordings and cortical mapping. Both had apparently normal MRI. Chronic stimulation of the epileptic focus decreased the number of seizures more than 90% the seizure number while preserving motor function. None of the patients had side effects. Neuromodulation is proposed as a safe, efficient surgical alternative for motor seizure control.

Cerebral Anatomy of the Spider Monkey Ateles Geoffroyi Studied Using Magnetic Resonance Imaging. First Report: a Comparative Study with the Human Brain Homo Sapiens / Anatomía Cerebral del mono araña Ateles geoffroyi estudiada utilizando imágenes de resonancia magnética. Primer reporte: estudio comparativo con el cerebro humano Homo Sapiens

The objective of the present qualitative study was to analyze the morphological aspects of the inner cerebral anatomy of two species of primates, using magnetic resonance images (MRI): spider monkey (A. geoffroyi) and human (H. sapiens), on the basis of a comparative study of the cerebral structures of the two species, focusing upon the brain of the spider monkey and, primarily, its limbic system. In spite of being an endemic Western hemisphere species, a fact which is by its own right interesting for research due to this animal’s social organization and motor functions, the spider monkey (A. geoffroyi) has hardly been studied in regard to its neuroanatomy. MRI was carried out, in one spider monkey, employing a General Electric Signa 1.5 T scanner. This investigation was carried in accordance to international regulations for the protection of animals in captivity, taking into account all protective means utilized in experimental handling, and not leaving behind any residual effects, either physiological or behavioral. From a qualitative point of view, the brains of the spider monkey and the human were found to have similar structures. In reference to shape, the most similar structures were found in the limbic system; proportionally, however, cervi cal curvature, amygdala, hippocampus, anterior commissure and the colliculi, were larger in the spider monkey than in the human.

El objetivo del presente estudio cualitativo fue analizar los aspectos morfológicos de la anatomía cerebral interna utilizando imágenes de resonancia magnética (IRM) en dos especies de primates, El mono Araña (A. geoffroyi) y el humano (H. sapiens), tomando como base un estudio comparativo de las estructuras cerebrales de las dos especies, concentrándose primordialmente en el sistema límbico del cerebro del mono araña. Aunque es una especie común en el hemisferio occidental, es interesante para estudiar dada su organización social y funciones motoras, el mono araña (A. geoffroyi) ha sido poco estudiado en cuanto a su neuroanatomía. Las IRM fueron hechas a un mono araña utilizando un resonador General Electrics Signa 1.5 T. Esta investigación se llevo a cabo conforme a las leyes internacionales para la protección de animales en cautiverio y teniendo en cuenta todas las medidas de protección para el manejo experimental para evitar cualquier efecto residual de índole comportamental o fisiológico. Desde un punto de vista cualitativo, los cerebros del mono araña y el humano tenían estructuras similares. Con respecto a la forma, las estructuras más parecidas fueron encontradas en el sistema límbico, sin embargo la curvatura cervical, la amígdala, el hipocampo, la comisura anterior y el colículo fueron más grandes proporcionalmente en el mono araña que en el humano.

Electrical stimulation of the hippocampal epileptic foci for seizure control: a double-blind, long-term follow-up study.

PURPOSE: Our aim was to evaluate the safety and efficacy of electrical stimulation of the hippocampus in a long-term follow-up study, as well as its impact on memory performance in the treatment of patients with refractory mesial temporal lobe epilepsy. METHODS: Nine patients were included. All had refractory partial complex seizures, some with secondary generalizations. All patients had a 3-month-baseline-seizure count, after which they underwent bilateral hippocampal diagnostic electrode implantation to establish focus laterality and location. Three patients had bilateral, and six, unilateral foci. Diagnostic electrodes were explanted and definitive Medtronic electrodes were implanted directed into the hippocampal foci. Position was confirmed with MRI and afterwards, the deep brain stimulation system internalized. Patients signed the informed consent approved by the Hospital's Ethics Committee and began a double-blind stimulation protocol. Patients attended a medical appointment every 3 months for seizure diary collection, deep brain stimulation system checkup, and neuropsychological testing. RESULTS: Follow-up ranged from 18 months to 7 years. Patients were divided in two groups: five had normal MRIs and seizure reduction of >95%, while four had hippocampal sclerosis and seizure reduction of 50-70%. No patient had neuropsychological deterioration, nor did any patient show side effects. Three patients were explanted after 2 years due to skin erosion in the trajectory of the system. CONCLUSIONS: Electrical stimulation of the hippocampus provides a nonlesional method that improves seizure outcome without memory deterioration in patients with hippocampal epileptic foci.