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1.
Sensors (Basel) ; 23(23)2023 Nov 23.
Article in English | MEDLINE | ID: mdl-38067737

ABSTRACT

Rural communities in Mexico and other countries with limited economic resources require a low-cost measurement system for the piezometric level and temperature of groundwater for their sustainable management, since anthropogenic action (pumping extractions), natural recharge and climate change phenomena affect the behavior of piezometric levels in the aquifer and its sustainability is at risk. Decrease in the piezometric level under a balanced level promotes salt intrusion from ocean water to the aquifer, salinizing and deteriorating the water quality for agriculture and other activities; and a decrease in water level under the pumps or well drilling depth could deprive communities of water. Water temperature monitoring is essential to determine electric conductivity and dissolved salt content in groundwater. Using IoT technology, a device was developed that monitors both variables inside the well, and the ambient temperature and atmospheric pressure outside the well. The measurements are made in real time, with sampling every second and sending data to a dedicated server every 15 min so that the visualization can be accessed through a device with Internet access. The time series of the variables measured inside and outside the well were obtained over a period of three months in the rural community of Agua Blanca, Guasave, Sinaloa, Mexico. Through these records, a progressive temporary drawdown of the piezometric level is observed, as well as the frequency of pumping. This low-cost IoT system shows potential use in hydrological processes of interest such as the separation of regional and local flow, drawdown rates and recognition of geohydrological parameters.

2.
WIREs Mech Dis ; 14(5): e1568, 2022 09.
Article in English | MEDLINE | ID: mdl-35712761

ABSTRACT

Generation of murine models for the study of birth-related pathologies has proven to be a complex and controversial problem. Differences in the relative timing of developmental events of both species have led some researchers to suggest that the rat is born comparatively less developed than the human. The solution proposed to this problem would consist in the delay of the experiments of perinatal asphyxia (PA), usually up to 7-10 days, allowing developmental levels to "equalize" with the human at birth. This solution generates a new set of problems. The developmental milestones in both species follow a divergent temporal pattern. Increasing the age of the rat not only can improve resemblance with humans but also will make the model miss a crucial set of milestones related to birth. During this process, there are specific mechanisms to protect the fetus from neuronal damage, especially those caused by asphyxia. These factors are not present in models where the asphyxia is delayed. In these models, there will be more false positives and more damage that would not be present in humans exposed to PA. This article is categorized under: Cancer > Stem Cells and Development Congenital Diseases > Environmental Factors Neurological Diseases > Environmental Factors.


Subject(s)
Asphyxia Neonatorum , Asphyxia , Animals , Asphyxia/etiology , Asphyxia Neonatorum/complications , Female , Humans , Infant, Newborn , Mice , Neurons/pathology , Pregnancy , Rats
3.
Genet Mol Biol ; 42(1): 125-131, 2019.
Article in English | MEDLINE | ID: mdl-30672977

ABSTRACT

The mobilome, portion of the genome composed of transposable elements (TEs), of Anopheles darlingi was described together with the genome of this species. Here, this mobilome was revised using similarity and de novo search approaches. A total of 5.6% of the A. darlingi genome is derived of TEs. Class I gypsy and copia were the most abundant superfamilies, corresponding to 22.36% of the mobilome. Non-LTR elements of the R1 and Jockey superfamilies account for 11% of the TEs. Among Class II TEs, the mariner superfamily is the most abundant (16.01%). Approximately 87% of the A. darlingi mobilome consist of short, truncated and/or degenerated copies of TEs. Only three retrotransposons, two belonging to gypsy and one to copia superfamilies, are putatively active elements. Only one Class II element, belonging to the mariner superfamily, is putatively active, having 12 copies in the genome. The TE landscape of A. darlingi is formed primarily by degenerated elements and, therefore, somewhat stable. Future applications of TE-based vectors for genetic transformation of A. darlingi should take into consideration mariner and piggyBac transposons, because full length and putatively active copies of these elements are present in its genome.

4.
Front Microbiol ; 7: 1946, 2016.
Article in English | MEDLINE | ID: mdl-27994579

ABSTRACT

Carbapenems represent the mainstay therapy for the treatment of serious P. aeruginosa infections. However, the emergence of carbapenem resistance has jeopardized the clinical use of this important class of compounds. The production of SPM-1 metallo-ß-lactamase has been the most common mechanism of carbapenem resistance identified in P. aeruginosa isolated from Brazilian medical centers. Interestingly, a single SPM-1-producing P. aeruginosa clone belonging to the ST277 has been widely spread within the Brazilian territory. In the current study, we performed a next-generation sequencing of six SPM-1-producing P. aeruginosa ST277 isolates. The core genome contains 5899 coding genes relative to the reference strain P. aeruginosa PAO1. A total of 26 genomic islands were detected in these isolates. We identified remarkable elements inside these genomic islands, such as copies of the blaSPM-1 gene conferring resistance to carbapenems and a type I-C CRISPR-Cas system, which is involved in protection of the chromosome against foreign DNA. In addition, we identified single nucleotide polymorphisms causing amino acid changes in antimicrobial resistance and virulence-related genes. Together, these factors could contribute to the marked resistance and persistence of the SPM-1-producing P. aeruginosa ST277 clone. A comparison of the SPM-1-producing P. aeruginosa ST277 genomes showed that their core genome has a high level nucleotide similarity and synteny conservation. The variability observed was mainly due to acquisition of genomic islands carrying several antibiotic resistance genes.

5.
Bioinformatics ; 31(17): 2915-7, 2015 Sep 01.
Article in English | MEDLINE | ID: mdl-25940562

ABSTRACT

MOTIVATION: Horizontal transfer of transposable (HTT) elements among eukaryotes was discovered in the mid-1980s. As then, >300 new cases have been described. New findings about HTT are revealing the evolutionary impact of this phenomenon on host genomes. In order to provide an up to date, interactive and expandable database for such events, we developed the HTT-DB database. RESULTS: HTT-DB allows easy access to most of HTT cases reported along with rich information about each case. Moreover, it allows the user to generate tables and graphs based on searches using Transposable elements and/or host species classification and export them in several formats. AVAILABILITY AND IMPLEMENTATION: This database is freely available on the web at http://lpa.saogabriel.unipampa.edu.br:8080/httdatabase. HTT-DB was developed based on Java and MySQL with all major browsers supported. Tools and software packages used are free for personal or non-profit projects. CONTACT: bdotto82@gmail.com or gabriel.wallau@gmail.com.


Subject(s)
DNA Transposable Elements/genetics , Databases, Factual , Eukaryota/genetics , Gene Transfer, Horizontal , Genome , Software , Animals , Eukaryota/classification , Evolution, Molecular , Humans , Species Specificity
6.
Mol Genet Genomics ; 290(1): 67-78, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25146840

ABSTRACT

Evidences of horizontal transfer, the exchange of genetic material between reproductively isolated species, have accumulated over the last decades, including for multicellular eukaryotic organisms. However, the mechanisms and ecological relationships that promote such phenomenon is still poorly known. Host-parasite interaction is one type of relationship usually pointed in the literature that could potentially increase the probability of the horizontal transfer between species, because the species involved in such relationships are generally in close contact. Transposable elements, which are well-known genomic parasites, are DNA entities that tend to be involved in horizontal transfer due to their ability to mobilize between different genomic locations. Using Drosophila species and their parasitoid wasps as a host-parasite model, we evaluated the hypothesis that horizontal transposon transfers (HTTs) are more frequent in this set of species than in species that do not exhibit a close ecological and phylogenetic relationship. For this purpose, we sequenced two sets of species using a metagenomic and single-species genomic sampling approach through next-generation DNA sequencing. The first set was composed of five generalist Drosophila (D. maculifrons, D. bandeirantorum, D. polymorpha, D. mercatorum and D. willistoni) species and their associated parasitoid wasps, whereas the second set was composed of D. incompta, which is a flower specialist species, and its parasitoid wasp. We did not find strong evidence of HTT in the two sets of Drosophila and wasp parasites. However, at least five cases of HTT were observed between the generalist and specialist Drosophila species. Moreover, we detected an HT event involving a Wolbachia lineage between generalist and specialist species, indicating that these endosymbiotic bacteria could play a role as HTT vectors. In summary, our results do not support the hypothesis of prevalent HTT between species with a host-parasite relationship, at least for the studied wasp-Drosophila pairs. Moreover, it suggests that other mechanisms or parasites are involved in promoting HTT between Drosophila species as the Wolbachia endosymbiotic bacteria.


Subject(s)
DNA Transposable Elements/genetics , Drosophila/parasitology , Gene Transfer, Horizontal/genetics , Host-Parasite Interactions , Wasps/physiology , Animals , Base Sequence , Drosophila/microbiology , Genes, Mitochondrial , Genome, Insect/genetics , Phylogeny , Reproducibility of Results , Species Specificity , Wasps/virology , Wolbachia/physiology
7.
PLoS Negl Trop Dis ; 8(9): e3176, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25233456

ABSTRACT

BACKGROUND: Trypanosoma rangeli is a hemoflagellate protozoan parasite infecting humans and other wild and domestic mammals across Central and South America. It does not cause human disease, but it can be mistaken for the etiologic agent of Chagas disease, Trypanosoma cruzi. We have sequenced the T. rangeli genome to provide new tools for elucidating the distinct and intriguing biology of this species and the key pathways related to interaction with its arthropod and mammalian hosts. METHODOLOGY/PRINCIPAL FINDINGS: The T. rangeli haploid genome is ∼ 24 Mb in length, and is the smallest and least repetitive trypanosomatid genome sequenced thus far. This parasite genome has shorter subtelomeric sequences compared to those of T. cruzi and T. brucei; displays intraspecific karyotype variability and lacks minichromosomes. Of the predicted 7,613 protein coding sequences, functional annotations could be determined for 2,415, while 5,043 are hypothetical proteins, some with evidence of protein expression. 7,101 genes (93%) are shared with other trypanosomatids that infect humans. An ortholog of the dcl2 gene involved in the T. brucei RNAi pathway was found in T. rangeli, but the RNAi machinery is non-functional since the other genes in this pathway are pseudogenized. T. rangeli is highly susceptible to oxidative stress, a phenotype that may be explained by a smaller number of anti-oxidant defense enzymes and heat-shock proteins. CONCLUSIONS/SIGNIFICANCE: Phylogenetic comparison of nuclear and mitochondrial genes indicates that T. rangeli and T. cruzi are equidistant from T. brucei. In addition to revealing new aspects of trypanosome co-evolution within the vertebrate and invertebrate hosts, comparative genomic analysis with pathogenic trypanosomatids provides valuable new information that can be further explored with the aim of developing better diagnostic tools and/or therapeutic targets.


Subject(s)
Genome, Protozoan , Phylogeny , Trypanosoma rangeli/genetics , Animals , Base Sequence , DNA, Protozoan/genetics , Haploidy , Humans
8.
Genome Biol Evol ; 4(8): 689-99, 2012.
Article in English | MEDLINE | ID: mdl-22798449

ABSTRACT

The genetic similarity observed among species is normally attributed to the existence of a common ancestor. However, a growing body of evidence suggests that the exchange of genetic material is not limited to the transfer from parent to offspring but can also occur through horizontal transfer (HT). Transposable elements (TEs) are DNA fragments with an innate propensity for HT; they are mobile and possess parasitic characteristics that allow them to exist and proliferate within host genomes. However, horizontal transposon transfer (HTT) is not easily detected, primarily because the complex TE life cycle can generate phylogenetic patterns similar to those expected for HTT events. The increasingly large number of new genome projects, in all branches of life, has provided an unprecedented opportunity to evaluate the TE content and HTT events in these species, although a standardized method of HTT detection is required before trends in the HTT rates can be evaluated in a wide range of eukaryotic taxa and predictions about these events can be made. Thus, we propose a straightforward hypothesis test that can be used by TE specialists and nonspecialists alike to discriminate between HTT events and natural TE life cycle patterns. We also discuss several plausible explanations and predictions for the distribution and frequency of HTT and for the inherent biases of HTT detection. Finally, we discuss some of the methodological concerns for HTT detection that may result in the underestimation and overestimation of HTT rates during eukaryotic genome evolution.


Subject(s)
DNA Transposable Elements , Eukaryota/genetics , Gene Transfer, Horizontal , Animals , Eukaryota/classification , Evolution, Molecular , Genome , Species Specificity
9.
Mol Genet Genomics ; 287(7): 531-40, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22610468

ABSTRACT

Genomic searches for P-like transposable elements were performed (1) in silico in the 12 available Drosophila genomes and (2) by PCR using degenerate primers in 21 Neotropical Drosophila species. In silico searches revealed P-like sequences only in Drosophila persimilis and Drosophila willistoni. Sixteen new P-like elements were obtained by PCR. These sequences were added to sequences of previously described P-like elements, and a phylogenetic analysis was performed. The subfamilies of P-elements described in the literature (Canonical, M, O, T, and K) were included in the reconstructed tree, and all were monophyletic. However, we suggest that some subfamilies can be enlarged, other subdivided, and some new subfamilies may be proposed, totalizing eleven subfamilies, most of which contain new P-like sequences. Our analyses support the monophyly of P-like elements in Drosophilidae. We suggest that, once these elements need host-specific factors to be mobilizable, the horizontal transfer (HT) of P-like elements may be inhibited among more distant taxa. Nevertheless, HT among Drosophilidae species appears to be a common phenomenon.


Subject(s)
DNA Transposable Elements/genetics , Drosophila/genetics , Phylogeny , Animals , Drosophila/classification , Evolution, Molecular , Genetic Variation , Molecular Sequence Data , Sequence Analysis, DNA , Species Specificity
10.
Genetica ; 138(6): 649-55, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20127503

ABSTRACT

Transposable elements (TEs) comprise a significant fraction of the genome, and some models of the TE "life cycle" suggest that, in the last phases of the cycle, TEs should be represented, in the genomes, by inactive and degenerated copies. In this study, we analyzed, using a bioinformatics approach, the autonomous hAT elements and their derivatives (active non-autonomous, MITE relatives and degenerated copies) in 12 Drosophila genomes. We found 28 hAT elements that had derivatives. Most copies had features that suggested that they were active, while only a few degenerated copies were found. Because hAT elements comprise an evolutionarily old superfamily, one should expect to find many degenerated copies within the genome, although this was not observed in our study. These results suggest that primarily active copies of hAT elements are maintained in the euchromatic regions of the genome and that degenerated copies are removed from the genome by natural selection.


Subject(s)
DNA Transposable Elements/genetics , Drosophila/genetics , Genome, Insect , Animals , Base Sequence , Molecular Sequence Data
11.
Genetica ; 135(1): 67-75, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18340538

ABSTRACT

In silico searches for sequences homologous to hAT elements in 12 Drosophila genomes have allowed us to identify 37 new hAT elements (8 in D. ananassae, 11 in D. mojavensis, 2 in D. sechellia, 1 in D. simulans, 2 in D. virilis, 3 in D. yakuba, 3 in D. persimilis, 1 in D. grimshawi, 5 in D. willistoni and 1 in D. pseudobscura). The size of these elements varies from 2,359 to 4,962 bp and the terminal inverted repeats (TIRs) show lengths ranging from 10 to 24 bp. Several elements show intact transposase ORFs, suggesting that they are active. Conserved amino acid motifs were identified that correspond to those important for transposase activity. These elements are highly variable and phylogenetic analysis showed that they can be clustered into four different families. Incongruencies were observed between the phylogenies of the transposable elements and those of their hosts, suggesting that horizontal transfer may have occurred between some of the species.


Subject(s)
DNA Transposable Elements , Drosophila Proteins/genetics , Drosophila/genetics , Genome, Insect , Transposases/genetics , Amino Acid Sequence , Animals , Codon, Nonsense/analysis , Consensus Sequence/genetics , Drosophila Proteins/analysis , Electronic Data Processing , Evolution, Molecular , Gene Transfer, Horizontal , Molecular Sequence Data , Open Reading Frames , Phylogeny , Sequence Analysis, DNA , Species Specificity , Terminal Repeat Sequences , Transposases/analysis , Zinc Fingers/genetics
12.
Genet Res (Camb) ; 90(3): 243-52, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18593511

ABSTRACT

The hobo-related sequences (hRSs) were considered as degenerate and inactive elements until recently, when one mobilizable copy was described. Using this sequence as the initial seed to search for homologous sequences in 12 available Drosophila genomes, in addition to searching for these sequences by PCR and Southern blot in nine other species, we found homologous sequences in every species of the Drosophila melanogaster species subgroup. Some evidence suggests that these non-autonomous sequences were kept mobilizable for at least 0.4 million years. Also, some very short sequences with miniature inverted-repeat transposable element (MITE) characteristics were found among these hRSs. These hRSs and their 'MITE-like' counterparts could provide a good example of the steps proposed in models that describe the MITEs origin.


Subject(s)
DNA Transposable Elements , Drosophila melanogaster/genetics , Animals , Blotting, Southern , Drosophila/genetics , Drosophila Proteins/genetics , Evolution, Molecular , Genome, Insect , Transposases/genetics
13.
Genet. mol. biol ; 30(1,suppl): 283-289, 2007. ilus
Article in English | LILACS | ID: lil-450446

ABSTRACT

We have analyzed the sequenced genomes of three strains of Mycoplasma hyopneumoniae and one strain of M. synoviae, and have found three and two different transposable element families, respectively in each species. In M. hyopneumoniae, the Insertion Sequences of the IS4 family is represented by ISMHp1, a putatively active element. The IS3 family is represented by several degenerated sequences. A third element called tMH was found, which shows some characteristics reminiscent of retrotransposons. In M. synoviae, three different possibly active IS4 elements are present (ISMHp1-like; ISMs1 and IS1634-like elements). The IS30 family is represented by the degenerated IS1630-like element. The IS1634-like element is shown to be involved in chromosomal rearrangements and horizontal gene transfer (HGT). The ISMHp1-like element is shown to relate to the HGT of a 25-kb region from M. gallisepticum to M. synoviae. The fractions of these genomes that correspond to mobile elements varied from 1.35 to 3.13 percent in M. hyopneumonia strains and was 2.08 percent in M. synoviae. Although these species possess reduced genomes, they maintain mobile elements, perhaps as a mechanism for genetic variability production.

14.
Curr Treat Options Cardiovasc Med ; 3(6): 507-513, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11696270

ABSTRACT

Heart failure with normal ejection fraction, also known as diastolic heart failure, is a major problem for patients and health-care providers and is a substantial expense to society. The main pathophysiologic processes involved are increased left ventricular stiffness and abnormal relaxation, with resulting impaired left ventricular filling. These processes typically displace the pressure-volume relationship in an upward direction, resulting in increased left ventricular end-diastolic, left atrial, and pulmonary capillary wedge pressures, leading to symptoms of pulmonary congestion. The most common clinical disorders leading to diastolic heart failure are 1) hypertension with concentric left ventricular hypertrophy, 2) coronary artery disease with decreased left ventricular compliance, 3) hypertrophic cardiomyopathy, and 4) aortic stenosis with concentric left ventricular hypertrophy. Echocardiography and cardiac catheterization with magnetic resonance imaging hold promise as future diagnostic tools. The approach to the treatment of diastolic heart failure is focused on four treatment goals: 1) persistent control of elevated blood pressure, with regression of left ventricular hypertrophy, 2) careful reduction of central blood volume (diuretics), 3) maintenance of atrial contraction and control of heart rate (beta-blockers, digoxin, atrioventricular pacing); and 4) improvement of left ventricular relaxation. There is currently no drug treatment specific for abnormal relaxation, although efforts are being made to develop such compounds. A promising future therapy includes agents that lyse advanced glycation end-products as an approach to relieving increased ventricular stiffness. In addition to pharmacotherapy, maintaining ideal body weight and a regular exercise program are also helpful in the treatment of diastolic heart failure. Although the overall prognosis of patients with diastolic dysfunction is more favorable than that of patients with systolic dysfunction, the frequency of treatment failure and recurrent symptoms underscores the need for further improvement in treatment of this condition.

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