Identification of Mutant Genes and Introgressed Tiger Salamander DNA in the Laboratory Axolotl, Ambystoma mexicanum.

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Woodcock, M Ryan; Vaughn-Wolfe, Jennifer; Elias, Alexandra; Kump, D Kevin; Kendall, Katharina Denise; Timoshevskaya, Nataliya; Timoshevskiy, Vladimir; Perry, Dustin W; Smith, Jeramiah J; Spiewak, Jessica E; Parichy, David M; Voss, S Randal

2017-01-31

The molecular genetic toolkit of the Mexican axolotl, a classic model organism, has matured to the point where it is now possible to identify genes for mutant phenotypes. We used a positional cloning-candidate gene approach to identify molecular bases for two historic axolotl pigment phenotypes: white and albino. White (d/d) mutants have defects in pigment cell morphogenesis and differentiation, whereas albino (a/a) mutants lack melanin. We identified in white mutants a transcriptional defect in endothelin 3 (edn3), encoding a peptide factor that promotes pigment cell migration and differentiation in other vertebrates. Transgenic restoration of Edn3 expression rescued the homozygous white mutant phenotype. We mapped the albino locus to tyrosinase (tyr) and identified polymorphisms shared between the albino allele (tyr a ) and tyr alleles in a Minnesota population of tiger salamanders from which the albino trait was introgressed. tyr a has a 142 bp deletion and similar engineered alleles recapitulated the albino phenotype. Finally, we show that historical introgression of tyr a significantly altered genomic composition of the laboratory axolotl, yielding a distinct, hybrid strain of ambystomatid salamander. Our results demonstrate the feasibility of identifying genes for traits in the laboratory Mexican axolotl.

Courtship Pheromone Use in a Model Urodele, the Mexican Axolotl (Ambystoma mexicanum).

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Maex, Margo; Van Bocxlaer, Ines; Mortier, Anneleen; Proost, Paul; Bossuyt, Franky

2016-02-04

Sex pheromones have been shown to constitute a crucial aspect of salamander reproduction. Until now, courtship pheromones of Salamandridae and Plethodontidae have been intensively studied, but information on chemical communication in other urodelan families is essentially lacking. The axolotl (Ambystoma mexicanum, Ambystomatidae) has a courtship display that suggests a key role for chemical communication in the orchestration of its sexual behavior, but no sex pheromones have yet been characterized from this species. Here we combined whole transcriptome analyses of the male cloaca with proteomic analyses of water in which axolotls were allowed to court to show that male axolotls secrete multiple ca. 20 kDa glycosylated sodefrin precursor-like factor (SPF) proteins during courtship. In combination with phylogenetic analyses, our data show that the male cloaca essentially secretes a courtship-specific clade of SPF proteins that is orthologous to salamandrid courtship pheromones. In addition, we identified an SPF protein for which no orthologs have been described from other salamanders so far. Overall, our study advocates a central role for SPF proteins during the courtship display of axolotls and adds knowledge on pheromone use in a previously unexplored deep evolutionary branch of salamander evolution.

A Tissue-Mapped Axolotl De Novo Transcriptome Enables Identification of Limb Regeneration Factors

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Donald M. Bryant

2017-01-01

Full Text Available Mammals have extremely limited regenerative capabilities; however, axolotls are profoundly regenerative and can replace entire limbs. The mechanisms underlying limb regeneration remain poorly understood, partly because the enormous and incompletely sequenced genomes of axolotls have hindered the study of genes facilitating regeneration. We assembled and annotated a de novo transcriptome using RNA-sequencing profiles for a broad spectrum of tissues that is estimated to have near-complete sequence information for 88% of axolotl genes. We devised expression analyses that identified the axolotl orthologs of cirbp and kazald1 as highly expressed and enriched in blastemas. Using morpholino anti-sense oligonucleotides, we find evidence that cirbp plays a cytoprotective role during limb regeneration whereas manipulation of kazald1 expression disrupts regeneration. Our transcriptome and annotation resources greatly complement previous transcriptomic studies and will be a valuable resource for future research in regenerative biology.

Hyperbaric oxygen therapy in a true regenerative environment, the regenerating limb of the axolotl

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Hansen, Kasper; Lauridsen, Henrik; Pedersen, Michael

2012-01-01

vertebrates such as the urodele amphibians (salamanders and newts), are excellent animal models for regenerative studies. The iconic Mexican axolotl (Ambystoma mexicanum) is capable of regenerating whole limbs, tail, jaw, and many inner organs, by dedifferentiation of cells to form a blastema (collection...

Propofol (2,6-diisopropylphenol) is an applicable immersion anesthetic in the axolotl with potential uses in hemodynamic and neurophysiological experiments

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Thygesen, Mathias; Rasmussen, Mikkel Mylius; Madsen, Jesper Guldsmed

2017-01-01

The Mexican axolotl (Ambystoma mexicanum) is an important model species in regenerative biology. Traditionally, axolotls are anesthetized using benzocaine or MS-222, both of which act to inhibit voltage gated sodium channels thereby preventing action potential propagation. In some...... neurophysiological experiments this is not desirable; therefore we tested propofol as an alternative anesthetic in the axolotl. We evaluated benzocaine, MS-222, and propofol's cardiovascular effects, effects on action potential propagation in the spinal cord, and gross limb regenerative effects. We found...... that propofol is applicable as a general anesthetic in the axolotl allowing for neurophysiological experiments and yielding a stable anesthesia with significantly less cardiovascular effect than both benzocaine and MS-222. Additionally, propofol did not affect gross limb regeneration. In conclusion we suggest...

Myofibril-Inducing RNA (MIR is essential for tropomyosin expression and myofibrillogenesis in axolotl hearts

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Lemanski Sharon L

2009-09-01

Full Text Available Abstract The Mexican axolotl, Ambystoma mexicanum, carries the naturally-occurring recessive mutant gene 'c' that results in a failure of homozygous (c/c embryos to form hearts that beat because of an absence of organized myofibrils. Our previous studies have shown that a noncoding RNA, Myofibril-Inducing RNA (MIR, is capable of promoting myofibrillogenesis and heart beating in the mutant (c/c axolotls. The present study demonstrates that the MIR gene is essential for tropomyosin (TM expression in axolotl hearts during development. Gene expression studies show that mRNA expression of various tropomyosin isoforms in untreated mutant hearts and in normal hearts knocked down with double-stranded MIR (dsMIR are similar to untreated normal. However, at the protein level, selected tropomyosin isoforms are significantly reduced in mutant and dsMIR treated normal hearts. These results suggest that MIR is involved in controlling the translation or post-translation of various TM isoforms and subsequently of regulating cardiac contractility.

Gallium nitrate: effects on cartilage during limb regeneration in the axolotl, Ambystoma mexicanum.

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Tassava, Roy A; Mendenhall, Luciara; Apseloff, Glen; Gerber, Nicholas

2002-09-01

Gallium nitrate, a drug shown to have efficacy in Paget's disease of bone, hypercalcemia of malignancy, and a variety of experimental autoimmune diseases, also inhibits the growth of some types of cancer. We examined dose and timing of administration of gallium nitrate on limb regeneration in the Mexican axolotl, Ambystoma mexicanum. Administered by intraperitoneal injection, gallium nitrate inhibited limb regeneration in a dose-dependent manner. Gallium nitrate initially suppressed epithelial wound healing and subsequently distorted both anterior-posterior and proximo-distal chondrogenic patterns. Gallium nitrate given at three days after amputation severely inhibited regeneration at high doses (6.25 mg/axolotl) and altered the normal patterning of the regenerates at low doses (3.75 mg/axolotl). Administration of 6.25 mg of gallium nitrate at four or 14 days prior to amputation also inhibited regeneration. In amputated limbs of gallium-treated axolotls, the chondrocytes were lost from inside the radius/ulna. Limbs that regenerated after gallium treatment was terminated showed blastema formation preferentially over the ulna. New cartilage of the regenerate often attached to the sides of the existing radius/ulna proximally into the stump and less so to the distal cut ends. J. Exp. Zool. 293:384-394, 2002. Copyright 2002 Wiley-Liss, Inc.

MRI tracking of SPIO labelled stem cells in a true regenerative environment, the regenerating limb of the axolotl

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Lauridsen, Henrik; Foldager, Casper Bindzus; Hagensen, Mette

are generally restricted by their limited regenerative potential. Conversely, excellent animal models for regenerative studies exist in lower vertebrates such as the urodele amphibians (salamanders and newts), exemplified in the iconic Mexican axolotl (Ambystoma mexicanum) capable of regenerating whole limbs...

Patterns of spatial and temporal visceral arch muscle development in the Mexican axolotl (Ambystoma mexicanum).

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Ericsson, Rolf; Olsson, Lennart

2004-08-01

Vertebrate head development is a classical topic that has received renewed attention during the last decade. Most reports use one of a few model organisms (chicken, mouse, zebrafish) and have focused on molecular mechanisms and the role of the neural crest, while cranial muscle development has received less attention. Here we describe cranial muscle differentiation and morphogenesis in the Mexican axolotl, Ambystoma mexicanum. To determine the onset of differentiation we use antibodies against desmin and optical sectioning using confocal laser scanning microscopy on whole-mount immunostained embryos. This technique makes it possible to document the cranial muscle in three dimensions while keeping the specimens intact. Desmin expression starts almost simultaneously in the first, second, and third visceral arch muscles (as in other amphibians studied). Muscle anlagen divide up early into the different elements which constitute the larval cranial musculature. We extend and refine earlier findings, e.g., by documenting a clear division between interhyoideus and interhyoideus posterior. The timing of cranial muscle differentiation differs among vertebrate groups, but seems to be constant within each group. This study provides a morphological foundation for further studies of muscle cell fate and early differentiation. Copyright 2004 Wiley-Liss, Inc.

Activation of germline-specific genes is required for limb regeneration in the Mexican axolotl

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Zhu, Wei; Pao, Gerald M; Satoh, Akira; Cummings, Gillian; Monaghan, James R; Harkins, Timothy T; Bryant, Susan V; Voss, S Randal; Gardiner, David M; Hunter, Tony

2013-01-01

The capacity for tissue and organ regeneration in humans is dwarfed by comparison to that of salamanders. Emerging evidence suggests that mechanisms learned from the early phase of salamander limb regeneration – wound healing, cellular dedifferentiation and blastemal formation – will reveal therapeutic approaches for tissue regeneration in humans. Here we describe a unique transcriptional fingerprint of regenerating limb tissue in the Mexican axolotl (Ambystoma mexicanum) that is indicative of cellular reprogramming of differentiated cells to a germline-like state. Two genes that are required for self-renewal of germ cells in mice and flies, Piwi-like 1 (PL1) and Piwi-like 2 (PL2), are expressed in limb blastemal cells, the basal layer keratinocytes and the thickened apical epithelial cap in the wound epidermis in the regenerating limb. Depletion of PL1 and PL2 by morpholino oligonucleotides decreased cell proliferation and increased cell death in the blastema leading to a significant retardation of regeneration. Examination of key molecules that are known to be required for limb development or regeneration further revealed that FGF8 is transcriptionally downregulated in the presence of the morpholino oligos, indicating PL1 and PL2 might participate in FGF signaling during limb regeneration. Given the requirement for FGF signaling in limb development and regeneration, the results suggest that PL1 and PL2 function to establish a unique germline-like state that is associated with successful regeneration. PMID:22841627

Regeneration of limb joints in the axolotl (Ambystoma mexicanum).

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Lee, Jangwoo; Gardiner, David M

2012-01-01

In spite of numerous investigations of regenerating salamander limbs, little attention has been paid to the details of how joints are reformed. An understanding of the process and mechanisms of joint regeneration in this model system for tetrapod limb regeneration would provide insights into developing novel therapies for inducing joint regeneration in humans. To this end, we have used the axolotl (Mexican Salamander) model of limb regeneration to describe the morphology and the expression patterns of marker genes during joint regeneration in response to limb amputation. These data are consistent with the hypothesis that the mechanisms of joint formation whether it be development or regeneration are conserved. We also have determined that defects in the epiphyseal region of both forelimbs and hind limbs in the axolotl are regenerated only when the defect is small. As is the case with defects in the diaphysis, there is a critical size above which the endogenous regenerative response is not sufficient to regenerate the joint. This non-regenerative response in an animal that has the ability to regenerate perfectly provides the opportunity to screen for the signaling pathways to induce regeneration of articular cartilage and joints.

Regeneration of limb joints in the axolotl (Ambystoma mexicanum.

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Jangwoo Lee

Full Text Available In spite of numerous investigations of regenerating salamander limbs, little attention has been paid to the details of how joints are reformed. An understanding of the process and mechanisms of joint regeneration in this model system for tetrapod limb regeneration would provide insights into developing novel therapies for inducing joint regeneration in humans. To this end, we have used the axolotl (Mexican Salamander model of limb regeneration to describe the morphology and the expression patterns of marker genes during joint regeneration in response to limb amputation. These data are consistent with the hypothesis that the mechanisms of joint formation whether it be development or regeneration are conserved. We also have determined that defects in the epiphyseal region of both forelimbs and hind limbs in the axolotl are regenerated only when the defect is small. As is the case with defects in the diaphysis, there is a critical size above which the endogenous regenerative response is not sufficient to regenerate the joint. This non-regenerative response in an animal that has the ability to regenerate perfectly provides the opportunity to screen for the signaling pathways to induce regeneration of articular cartilage and joints.

Neuregulin-1 signaling is essential for nerve-dependent axolotl limb regeneration.

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Farkas, Johanna E; Freitas, Polina D; Bryant, Donald M; Whited, Jessica L; Monaghan, James R

2016-08-01

The Mexican axolotl (Ambystoma mexicanum) is capable of fully regenerating amputated limbs, but denervation of the limb inhibits the formation of the post-injury proliferative mass called the blastema. The molecular basis behind this phenomenon remains poorly understood, but previous studies have suggested that nerves support regeneration via the secretion of essential growth-promoting factors. An essential nerve-derived factor must be found in the blastema, capable of rescuing regeneration in denervated limbs, and its inhibition must prevent regeneration. Here, we show that the neuronally secreted protein Neuregulin-1 (NRG1) fulfills all these criteria in the axolotl. Immunohistochemistry and in situ hybridization of NRG1 and its active receptor ErbB2 revealed that they are expressed in regenerating blastemas but lost upon denervation. NRG1 was localized to the wound epithelium prior to blastema formation and was later strongly expressed in proliferating blastemal cells. Supplementation by implantation of NRG1-soaked beads rescued regeneration to digits in denervated limbs, and pharmacological inhibition of NRG1 signaling reduced cell proliferation, blocked blastema formation and induced aberrant collagen deposition in fully innervated limbs. Taken together, our results show that nerve-dependent NRG1/ErbB2 signaling promotes blastemal proliferation in the regenerating limb and may play an essential role in blastema formation, thus providing insight into the longstanding question of why nerves are required for axolotl limb regeneration. © 2016. Published by The Company of Biologists Ltd.

Identification of differentially expressed thyroid hormone responsive genes from the brain of the Mexican Axolotl (Ambystoma mexicanum).

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Huggins, P; Johnson, C K; Schoergendorfer, A; Putta, S; Bathke, A C; Stromberg, A J; Voss, S R

2012-01-01

The Mexican axolotl (Ambystoma mexicanum) presents an excellent model to investigate mechanisms of brain development that are conserved among vertebrates. In particular, metamorphic changes of the brain can be induced in free-living aquatic juveniles and adults by simply adding thyroid hormone (T4) to rearing water. Whole brains were sampled from juvenile A. mexicanum that were exposed to 0, 8, and 18 days of 50 nM T4, and these were used to isolate RNA and make normalized cDNA libraries for 454 DNA sequencing. A total of 1,875,732 high quality cDNA reads were assembled with existing ESTs to obtain 5884 new contigs for human RefSeq protein models, and to develop a custom Affymetrix gene expression array (Amby_002) with approximately 20,000 probe sets. The Amby_002 array was used to identify 303 transcripts that differed statistically (p1.5) as a function of days of T4 treatment. Further statistical analyses showed that Amby_002 performed concordantly in comparison to an existing, small format expression array. This study introduces a new A. mexicanum microarray resource for the community and the first lists of T4-responsive genes from the brain of a salamander amphibian. Copyright © 2011 Elsevier Inc. All rights reserved.

Positive in vitro wound healing effects of functional inclusion bodies of a lipoxygenase from the Mexican axolotl.

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Stamm, Anne; Strauß, Sarah; Vogt, Peter; Scheper, Thomas; Pepelanova, Iliyana

2018-04-07

AmbLOXe is a lipoxygenase, which is up-regulated during limb-redevelopment in the Mexican axolotl, Ambystoma mexicanum, an animal with remarkable regeneration capacity. Previous studies have shown that mammalian cells transformed with the gene of this epidermal lipoxygenase display faster migration and wound closure rate during in vitro wound healing experiments. In this study, the gene of AmbLOXe was codon-optimized for expression in Escherichia coli and was produced in the insoluble fraction as protein aggregates. These inclusion bodies or nanopills were shown to be reservoirs containing functional protein during in vitro wound healing assays. For this purpose, functional inclusion bodies were used to coat cell culture surfaces prior cell seeding or were added directly to the medium after cells reached confluence. In both scenarios, AmbLOXe inclusion bodies led to faster migration rate and wound closure, in comparison to controls containing either no AmbLOXe or GFP inclusion bodies. Our results demonstrate that AmbLOXe inclusion bodies are functional and may serve as stable reservoirs of this enzyme. Nevertheless, further studies with soluble enzyme are also necessary in order to start elucidating the exact molecular substrates of AmbLOXe and the biochemical pathways involved in the wound healing effect.

Identification of Differentially Expressed Thyroid Hormone Responsive Genes from the Brain of the Mexican Axolotl (Ambystoma mexicanum) ✧

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Huggins, P; Johnson, CK; Schoergendorfer, A; Putta, S; Bathke, AC; Stromberg, AJ; Voss, SR

2011-01-01

The Mexican axolotl (Ambystoma mexicanum) presents an excellent model to investigate mechanisms of brain development that are conserved among vertebrates. In particular, metamorphic changes of the brain can be induced in free-living aquatic juveniles and adults by simply adding thyroid hormone (T4) to rearing water. Whole brains were sampled from juvenile A. mexicanum that were exposed to 0, 8, and 18 days of 50 nM T4, and these were used to isolate RNA and make normalized cDNA libraries for 454 DNA sequencing. A total of 1,875,732 high quality cDNA reads were assembled with existing ESTs to obtain 5,884 new contigs for human RefSeq protein models, and to develop a custom Affymetrix gene expression array (Amby_002) with approximately 20,000 probe sets. The Amby_002 array was used to identify 303 transcripts that differed statistically (p 1.5) as a function of days of T4 treatment. Further statistical analyses showed that Amby_002 performed concordantly in comparison to an existing, small format expression array. This study introduces a new A. mexicanum microarray resource for the community and the first lists of T4-responsive genes from the brain of a salamander amphibian. PMID:21457787

Probability of Regenerating a Normal Limb After Bite Injury in the Mexican Axolotl (Ambystoma mexicanum).

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Thompson, Sierra; Muzinic, Laura; Muzinic, Christopher; Niemiller, Matthew L; Voss, S Randal

2014-06-01

Multiple factors are thought to cause limb abnormalities in amphibian populations by altering processes of limb development and regeneration. We examined adult and juvenile axolotls ( Ambystoma mexicanum ) in the Ambystoma Genetic Stock Center (AGSC) for limb and digit abnormalities to investigate the probability of normal regeneration after bite injury. We observed that 80% of larval salamanders show evidence of bite injury at the time of transition from group housing to solitary housing. Among 717 adult axolotls that were surveyed, which included solitary-housed males and group-housed females, approximately half presented abnormalities, including examples of extra or missing digits and limbs, fused digits, and digits growing from atypical anatomical positions. Bite injury likely explains these limb defects, and not abnormal development, because limbs with normal anatomy regenerated after performing rostral amputations. We infer that only 43% of AGSC larvae will present four anatomically normal looking adult limbs after incurring a bite injury. Our results show regeneration of normal limb anatomy to be less than perfect after bite injury.

Muscular derivatives of the cranialmost somites revealed by long-term fate mapping in the Mexican axolotl (Ambystoma mexicanum).

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Piekarski, Nadine; Olsson, Lennart

2007-01-01

The fate of single somites has not been analyzed from a comparative perspective with modern cell-marking methods. Most of what we know is based on work using quail-chick chimeras. Consequently, to what degree cell fate has been conserved despite the anatomical differences among vertebrates is unknown. We have analyzed the cell fate of the cranialmost somites, with the focus on somite two, in the Mexican axolotl (Ambystoma mexicanum). Somite cells were marked by injection of dextran-fluorescein and detected using immunofluorescence after 2 months of development in paraffin sections. Our data confirm and extend earlier studies based on classical histology in salamanders. We show that somite two contributes to different muscles, skeletal elements, and connective tissues of the head and cranial trunk region. Cells from somites two and three migrate latero-ventrally and contribute to the hypobranchial muscles mm. geniohyoideus and rectus cervicis. We provide evidence that the specific formation of the hypobranchial musculature from ventral processes of the somites might be variable in different classes of vertebrates. We further demonstrate that mm. cucullaris and dilatator laryngis, which were earlier thought to have a branchial origin, arise from somitic material in a manner very similar to the findings in quail-chick chimeras. Our findings indicate that the pattern of somitic derivatives is highly conserved within tetrapods.

Thyroxine-induced metamorphosis in the axolotl (Ambystoma mexicanum).

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Coots, Peggy S; Seifert, Ashley W

2015-01-01

The axolotl (Ambystoma mexicanum) has remained an important model for regeneration and developmental biology for over a century. Although axolotls in captive-bred colonies usually exist in an aquatic form, they retain the ability to undergo metamorphosis following exposure to thyroid hormone. Here we present a robust method for inducing metamorphosis in adult axolotls that results in high survivability and produces terrestrial animals that can be maintained in long-term captivity.

Diffusion tensor tractography reveals muscle reconnection during axolotl limb regeneration.

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Cheng-Han Wu

Full Text Available Axolotls have amazing ability to regenerate their lost limbs. Our previous works showed that after amputation the remnant muscle ends remained at their original location whilst sending satellite cells into the regenerating parts to develop into early muscle fibers in the late differentiation stage. The parental and the newly formed muscle fibers were not connected until very late stage. The present study used non-invasive diffusion tensor imaging (DTI to monitor weekly axolotl upper arm muscles after amputation of their upper arms. DTI tractography showed that the regenerating muscle fibers became visible at 9-wpa (weeks post amputation, but a gap was observed between the regenerating and parental muscles. The gap was filled at 10-wpa, indicating reconnection of the fibers of both muscles. This was confirmed by histology. The DTI results indicate that 23% of the muscle fibers were reconnected at 10-wpa. In conclusion, DTI can be used to visualize axolotls' skeletal muscles and the results of muscle reconnection were in accordance with our previous findings. This non-invasive technique will allow researchers to identify the timeframe in which muscle fiber reconnection takes place and thus enable the study of the mechanisms underlying this reconnection.

Pathological features of olfactory neuroblastoma in an axolotl (Ambystoma mexicanum).

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Shioda, Chieko; Uchida, Kazuyuki; Nakayama, Hiroyuki

2011-08-01

A one-year-old, female Mexican axolotl (Ambystoma mexicanum) had a rough-surfaced, polypoid, pink tumor mass of approximately 10 mm in diameter in the oral cavity. Histologically, the tumor extended from the ethmoturbinate region and into the oral cavity and had replaced some of the maxillary bone tissue. The tumor mass was composed of a lobular architecture of small round-shaped tumor cells with occasional Flexner-Wintersteiner-like rosette formation. There were no metastatic lesions in the other organs. Immunohistochemically, the tumor cells were partly positive for several neural markers (class III beta-tubulin, S-100 protein, and doublecortin) and intensely positive for an epithelial marker (cytokeratin AE1/AE3). These results suggest that the present tumor originated from neuroectodermal tissue. Considering the location and histological and immunohistochemical features of the tumor, a diagnosis of olfactory neuroblastoma was made.

Transcriptional landscapes of Axolotl (Ambystoma mexicanum).

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Caballero-Pérez, Juan; Espinal-Centeno, Annie; Falcon, Francisco; García-Ortega, Luis F; Curiel-Quesada, Everardo; Cruz-Hernández, Andrés; Bako, Laszlo; Chen, Xuemei; Martínez, Octavio; Alberto Arteaga-Vázquez, Mario; Herrera-Estrella, Luis; Cruz-Ramírez, Alfredo

2018-01-15

The axolotl (Ambystoma mexicanum) is the vertebrate model system with the highest regeneration capacity. Experimental tools established over the past 100 years have been fundamental to start unraveling the cellular and molecular basis of tissue and limb regeneration. In the absence of a reference genome for the Axolotl, transcriptomic analysis become fundamental to understand the genetic basis of regeneration. Here we present one of the most diverse transcriptomic data sets for Axolotl by profiling coding and non-coding RNAs from diverse tissues. We reconstructed a population of 115,906 putative protein coding mRNAs as full ORFs (including isoforms). We also identified 352 conserved miRNAs and 297 novel putative mature miRNAs. Systematic enrichment analysis of gene expression allowed us to identify tissue-specific protein-coding transcripts. We also found putative novel and conserved microRNAs which potentially target mRNAs which are reported as important disease candidates in heart and liver. Copyright © 2017 Elsevier Inc. All rights reserved.

Comparative pelvic development of the axolotl (Ambystoma mexicanum) and the Australian lungfish (Neoceratodus forsteri): conservation and innovation across the fish-tetrapod transition.

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Boisvert, Catherine Anne; Joss, Jean Mp; Ahlberg, Per E

2013-01-23

The fish-tetrapod transition was one of the major events in vertebrate evolution and was enabled by many morphological changes. Although the transformation of paired fish fins into tetrapod limbs has been a major topic of study in recent years, both from paleontological and comparative developmental perspectives, the interest has focused almost exclusively on the distal part of the appendage and in particular the origin of digits. Relatively little attention has been paid to the transformation of the pelvic girdle from a small unipartite structure to a large tripartite weight-bearing structure, allowing tetrapods to rely mostly on their hindlimbs for locomotion. In order to understand how the ischium and the ilium evolved and how the acetabulum was reoriented during this transition, growth series of the Australian lungfish Neoceratodus forsteri and the Mexican axolotl Ambystoma mexicanum were cleared and stained for cartilage and bone and immunostained for skeletal muscles. In order to understand the myological developmental data, hypotheses about the homologies of pelvic muscles in adults of Latimeria, Neoceratodus and Necturus were formulated based on descriptions from the literature of the coelacanth (Latimeria), the Australian Lungfish (Neoceratodus) and a salamander (Necturus). In the axolotl and the lungfish, the chondrification of the pelvic girdle starts at the acetabula and progresses anteriorly in the lungfish and anteriorly and posteriorly in the salamander. The ilium develops by extending dorsally to meet and connect to the sacral rib in the axolotl. Homologous muscles develop in the same order with the hypaxial musculature developing first, followed by the deep, then the superficial pelvic musculature. Development of the pelvic endoskeleton and musculature is very similar in Neoceratodus and Ambystoma. If the acetabulum is seen as being a fixed landmark, the evolution of the ischium only required pubic pre-chondrogenic cells to migrate posteriorly. It

The axolotl (Ambystoma mexicanum), a neotenic amphibian, expresses functional thyroid hormone receptors.

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Safi, Rachid; Bertrand, Stéphanie; Marchand, Oriane; Duffraisse, Marilyne; de Luze, Amaury; Vanacker, Jean-Marc; Maraninchi, Marie; Margotat, Alain; Demeneix, Barbara; Laudet, Vincent

2004-02-01

Neotenic amphibians such as the axolotl (Ambystoma mexicanum) are often unable to undergo metamorphosis under natural conditions. It is thought that neoteny represents a deviation from the standard course of amphibian ontogeny, affecting the thyroid axis at different levels from the central nervous system to peripheral organs. Thyroid hormone receptors (TRs) that bind the thyroid hormone (TH) T(3) have been described in axolotl. However, the full sequences of TR were needed to better characterize the TH response and to be able to assess their functional capacity at the molecular level. We report that each of the alpha and beta axolotl TRs bind both DNA and TH, and they activate transcription in response to TH in a mammalian cell-based transient transfection assay. Moreover, both TRs are expressed in axolotl tissues. Interestingly, each TR gene generates alternatively spliced isoforms, harboring partial or total deletions of the ligand-binding domain, which are expressed in vivo. Further, we found that in the axolotl, TH regulates the expression of stromelysin 3 and collagenase 3, which are TH target genes in Xenopus. Taken together, these results suggest that axolotl TRs are functional and that the molecular basis of neoteny in the axolotl is not linked to a major defect in TH response in peripheral tissues.

Terminal-Nerve-Derived Neuropeptide Y Modulates Physiological Responses in the Olfactory Epithelium of Hungry Axolotls (Ambystoma mexicanum)

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Mousley, Angela; Polese, Gianluca; Marks, Nikki J.; Eisthen, Heather L.

2007-01-01

The vertebrate brain actively regulates incoming sensory information, effectively filtering input and focusing attention toward environmental stimuli that are most relevant to the animal's behavioral context or physiological state. Such centrifugal modulation has been shown to play an important role in processing in the retina and cochlea, but has received relatively little attention in olfaction. The terminal nerve, a cranial nerve that extends underneath the lamina propria surrounding the olfactory epithelium, displays anatomical and neurochemical characteristics that suggest that it modulates activity in the olfactory epithelium. Using immunocytochemical techniques, we demonstrate that neuropeptide Y (NPY) is abundantly present in the terminal nerve in the axolotl (Ambystoma mexicanum), an aquatic salamander. Because NPY plays an important role in regulating appetite and hunger in many vertebrates, we investigated the possibility that NPY modulates activity in the olfactory epithelium in relation to the animal's hunger level. We therefore characterized the full length NPY gene from axolotls to enable synthesis of authentic axolotl NPY for use in electrophysiological experiments. We find that axolotl NPY modulates olfactory epithelial responses evoked by L-glutamic acid, a food-related odorant, but only in hungry animals. Similarly, whole-cell patch-clamp recordings demonstrate that bath application of axolotl NPY enhances the magnitude of a tetrodotoxin-sensitive inward current, but only in hungry animals. These results suggest that expression or activity of NPY receptors in the olfactory epithelium may change with hunger level, and that terminal nerve-derived peptides modulate activity in the olfactory epithelium in response to an animal's changing behavioral and physiological circumstances. PMID:16855098

Terminal nerve-derived neuropeptide y modulates physiological responses in the olfactory epithelium of hungry axolotls (Ambystoma mexicanum).

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Mousley, Angela; Polese, Gianluca; Marks, Nikki J; Eisthen, Heather L

2006-07-19

The vertebrate brain actively regulates incoming sensory information, effectively filtering input and focusing attention toward environmental stimuli that are most relevant to the animal's behavioral context or physiological state. Such centrifugal modulation has been shown to play an important role in processing in the retina and cochlea, but has received relatively little attention in olfaction. The terminal nerve, a cranial nerve that extends underneath the lamina propria surrounding the olfactory epithelium, displays anatomical and neurochemical characteristics that suggest that it modulates activity in the olfactory epithelium. Using immunocytochemical techniques, we demonstrate that neuropeptide Y (NPY) is abundantly present in the terminal nerve in the axolotl (Ambystoma mexicanum), an aquatic salamander. Because NPY plays an important role in regulating appetite and hunger in many vertebrates, we investigated the possibility that NPY modulates activity in the olfactory epithelium in relation to the animal's hunger level. We therefore characterized the full-length NPY gene from axolotls to enable synthesis of authentic axolotl NPY for use in electrophysiological experiments. We find that axolotl NPY modulates olfactory epithelial responses evoked by l-glutamic acid, a food-related odorant, but only in hungry animals. Similarly, whole-cell patch-clamp recordings demonstrate that bath application of axolotl NPY enhances the magnitude of a tetrodotoxin-sensitive inward current, but only in hungry animals. These results suggest that expression or activity of NPY receptors in the olfactory epithelium may change with hunger level, and that terminal nerve-derived peptides modulate activity in the olfactory epithelium in response to an animal's changing behavioral and physiological circumstances.

Lens regeneration in axolotl: new evidence of developmental plasticity

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Suetsugu-Maki Rinako

2012-12-01

Full Text Available Abstract Background Among vertebrates lens regeneration is most pronounced in newts, which have the ability to regenerate the entire lens throughout their lives. Regeneration occurs from the dorsal iris by transdifferentiation of the pigment epithelial cells. Interestingly, the ventral iris never contributes to regeneration. Frogs have limited lens regeneration capacity elicited from the cornea during pre-metamorphic stages. The axolotl is another salamander which, like the newt, regenerates its limbs or its tail with the spinal cord, but up until now all reports have shown that it does not regenerate the lens. Results Here we present a detailed analysis during different stages of axolotl development, and we show that despite previous beliefs the axolotl does regenerate the lens, however, only during a limited time after hatching. We have found that starting at stage 44 (forelimb bud stage lens regeneration is possible for nearly two weeks. Regeneration occurs from the iris but, in contrast to the newt, regeneration can be elicited from either the dorsal or the ventral iris and, occasionally, even from both in the same eye. Similar studies in the zebra fish concluded that lens regeneration is not possible. Conclusions Regeneration of the lens is possible in the axolotl, but differs from both frogs and newts. Thus the axolotl iris provides a novel and more plastic strategy for lens regeneration.

Limb Regeneration in Axolotl: Is It Superhealing?

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Stéphane Roy

2006-01-01

Full Text Available The ability of axolotls to regenerate their limbs is almost legendary. In fact, urodeles such as the axolotl are the only vertebrates that can regenerate multiple structures like their limbs, jaws, tail, spinal cord, and skin (the list goes on throughout their lives. It is therefore surprising to realize, although we have known of their regenerative potential for over 200 years, how little we understand the mechanisms behind this achievement of adult tissue morphogenesis. Many observations can be drawn between regeneration and other disciplines such as development and wound healing. In this review, we present new developments in functional analysis that will help to address the role of specific genes during the process of regeneration. We also present an analysis of the resemblance between wound healing and regeneration, and discuss whether axolotls are superhealers. A better understanding of these animals' regenerative capacity could lead to major benefits by providing regenerative medicine with directions on how to develop therapeutic approaches leading to regeneration in humans.

Low submetamorphic doses of dexamethasone and thyroxine induce complete metamorphosis in the axolotl (Ambystoma mexicanum) when injected together.

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Kühn, Eduard R; De Groef, Bert; Grommen, Sylvia V H; Van der Geyten, Serge; Darras, Veerle M

2004-06-01

Entanglement of functions between the adrenal (or interrenal) and thyroid axis has been well described for all vertebrates and can be tracked down up to the level of gene expression. Both thyroid hormones and corticosteroids may induce morphological changes leading to metamorphosis climax in the neotenic Mexican axolotl (Ambystoma mexicanum). In a first series of experiments, metamorphosis was induced with an injection of 25 microg T(4) on three alternate days as judged by a decrease in body weight and tail height together with complete gill resorption. This injection also resulted in elevated plasma concentrations of T(3) and corticosterone. Previous results have indicated that the same dose of dexamethasone (DEX) is ineffective in this regard (Gen. Comp. Endocrinol. 127 (2002) 157). In a second series of experiments low doses of T(4) (0.5 microg) or DEX (5 microg) were ineffective to induce morphological changes. However, when these submetamorphic doses were injected together, morphological changes were observed within one week leading to complete metamorphosis. It is concluded that thyroid hormones combined with corticosteroids are essential for metamorphosis in the axolotl and that only high doses of either thyroid hormone or corticosteroid can induce morphological changes when injected separately.

Generation of axolotl hematopoietic chimeras

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David Lopez

2015-02-01

Full Text Available Wound repair is an extremely complex process that requires precise coordination between various cell types including immune cells.  Unfortunately, in mammals this usually results in scar formation instead of restoration of the original fully functional tissue, otherwise known as regeneration.  Various animal models like frogs and salamanders are currently being studied to determine the intracellular and intercellular pathways, controlled by gene expression, that elicit cell proliferation, differentiation, and migration of cells during regenerative healing.  Now, the necessary genetic tools to map regenerative pathways are becoming available for the axolotl salamander, thus allowing comparative studies between scarring and regeneration.  Here, we describe in detail three methods to produce axolotl hematopoietic cell-tagged chimeras for the study of hematopoiesis and regeneration.

Novel axolotl cardiac function analysis method using magnetic resonance imaging.

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Pedro Gomes Sanches

Full Text Available The salamander axolotl is capable of complete regeneration of amputated heart tissue. However, non-invasive imaging tools for assessing its cardiac function were so far not employed. In this study, cardiac magnetic resonance imaging is introduced as a non-invasive technique to image heart function of axolotls. Three axolotls were imaged with magnetic resonance imaging using a retrospectively gated Fast Low Angle Shot cine sequence. Within one scanning session the axolotl heart was imaged three times in all planes, consecutively. Heart rate, ejection fraction, stroke volume and cardiac output were calculated using three techniques: (1 combined long-axis, (2 short-axis series, and (3 ultrasound (control for heart rate only. All values are presented as mean ± standard deviation. Heart rate (beats per minute among different animals was 32.2±6.0 (long axis, 30.4±5.5 (short axis and 32.7±4.9 (ultrasound and statistically similar regardless of the imaging method (p > 0.05. Ejection fraction (% was 59.6±10.8 (long axis and 48.1±11.3 (short axis and it differed significantly (p = 0.019. Stroke volume (μl/beat was 133.7±33.7 (long axis and 93.2±31.2 (short axis, also differed significantly (p = 0.015. Calculations were consistent among the animals and over three repeated measurements. The heart rate varied depending on depth of anaesthesia. We described a new method for defining and imaging the anatomical planes of the axolotl heart and propose one of our techniques (long axis analysis may prove useful in defining cardiac function in regenerating axolotl hearts.

Musashi and Plasticity of Xenopus and Axolotl Spinal Cord Ependymal Cells

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Chernoff, Ellen A. G.; Sato, Kazuna; Salfity, Hai V. N.; Sarria, Deborah A.; Belecky-Adams, Teri

2018-01-01

The differentiated state of spinal cord ependymal cells in regeneration-competent amphibians varies between a constitutively active state in what is essentially a developing organism, the tadpole of the frog Xenopus laevis, and a quiescent, activatable state in a slowly growing adult salamander Ambystoma mexicanum, the Axolotl. Ependymal cells are epithelial in intact spinal cord of all vertebrates. After transection, body region ependymal epithelium in both Xenopus and the Axolotl disorganizes for regenerative outgrowth (gap replacement). Injury-reactive ependymal cells serve as a stem/progenitor cell population in regeneration and reconstruct the central canal. Expression patterns of mRNA and protein for the stem/progenitor cell-maintenance Notch signaling pathway mRNA-binding protein Musashi (msi) change with life stage and regeneration competence. Msi-1 is missing (immunohistochemistry), or at very low levels (polymerase chain reaction, PCR), in both intact regeneration-competent adult Axolotl cord and intact non-regeneration-competent Xenopus tadpole (Nieuwkoop and Faber stage 62+, NF 62+). The critical correlation for successful regeneration is msi-1 expression/upregulation after injury in the ependymal outgrowth and stump-region ependymal cells. msi-1 and msi-2 isoforms were cloned for the Axolotl as well as previously unknown isoforms of Xenopus msi-2. Intact Xenopus spinal cord ependymal cells show a loss of msi-1 expression between regeneration-competent (NF 50–53) and non-regenerating stages (NF 62+) and in post-metamorphosis froglets, while msi-2 displays a lower molecular weight isoform in non-regenerating cord. In the Axolotl, embryos and juveniles maintain Msi-1 expression in the intact cord. In the adult Axolotl, Msi-1 is absent, but upregulates after injury. Msi-2 levels are more variable among Axolotl life stages: rising between late tailbud embryos and juveniles and decreasing in adult cord. Cultures of regeneration-competent Xenopus tadpole

Musashi and Plasticity of Xenopus and Axolotl Spinal Cord Ependymal Cells

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Ellen A. G. Chernoff

2018-02-01

Full Text Available The differentiated state of spinal cord ependymal cells in regeneration-competent amphibians varies between a constitutively active state in what is essentially a developing organism, the tadpole of the frog Xenopus laevis, and a quiescent, activatable state in a slowly growing adult salamander Ambystoma mexicanum, the Axolotl. Ependymal cells are epithelial in intact spinal cord of all vertebrates. After transection, body region ependymal epithelium in both Xenopus and the Axolotl disorganizes for regenerative outgrowth (gap replacement. Injury-reactive ependymal cells serve as a stem/progenitor cell population in regeneration and reconstruct the central canal. Expression patterns of mRNA and protein for the stem/progenitor cell-maintenance Notch signaling pathway mRNA-binding protein Musashi (msi change with life stage and regeneration competence. Msi-1 is missing (immunohistochemistry, or at very low levels (polymerase chain reaction, PCR, in both intact regeneration-competent adult Axolotl cord and intact non-regeneration-competent Xenopus tadpole (Nieuwkoop and Faber stage 62+, NF 62+. The critical correlation for successful regeneration is msi-1 expression/upregulation after injury in the ependymal outgrowth and stump-region ependymal cells. msi-1 and msi-2 isoforms were cloned for the Axolotl as well as previously unknown isoforms of Xenopus msi-2. Intact Xenopus spinal cord ependymal cells show a loss of msi-1 expression between regeneration-competent (NF 50–53 and non-regenerating stages (NF 62+ and in post-metamorphosis froglets, while msi-2 displays a lower molecular weight isoform in non-regenerating cord. In the Axolotl, embryos and juveniles maintain Msi-1 expression in the intact cord. In the adult Axolotl, Msi-1 is absent, but upregulates after injury. Msi-2 levels are more variable among Axolotl life stages: rising between late tailbud embryos and juveniles and decreasing in adult cord. Cultures of regeneration

Identification of reference genes and validation for gene expression studies in diverse axolotl (Ambystoma mexicanum) tissues.

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Guelke, Eileen; Bucan, Vesna; Liebsch, Christina; Lazaridis, Andrea; Radtke, Christine; Vogt, Peter M; Reimers, Kerstin

2015-04-10

For the precise quantitative RT-PCR normalization a set of valid reference genes is obligatory. Moreover have to be taken into concern the experimental conditions as they bias the regulation of reference genes. Up till now, no reference targets have been described for the axolotl (Ambystoma mexicanum). In a search in the public database SalSite for genetic information of the axolotl we identified fourteen presumptive reference genes, eleven of which were further tested for their gene expression stability. This study characterizes the expressional patterns of 11 putative endogenous control genes during axolotl limb regeneration and in an axolotl tissue panel. All 11 reference genes showed variable expression. Strikingly, ACTB was to be found most stable expressed in all comparative tissue groups, so we reason it to be suitable for all different kinds of axolotl tissue-type investigations. Moreover do we suggest GAPDH and RPLP0 as suitable for certain axolotl tissue analysis. When it comes to axolotl limb regeneration, a validated pair of reference genes is ODC and RPLP0. With these findings, new insights into axolotl gene expression profiling might be gained. Copyright © 2015 Elsevier B.V. All rights reserved.

Misexpression experiment of Tbx5 in axolotl (Ambystoma mexicanum) hindlimb blastema.

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Shimokawa, Takashi; Kominami, Rieko; Yasutaka, Satoru; Shinohara, Harumichi

2013-01-01

Axolotls (Ambystoma mexicanum) have the ability to regenerate amputated limbs throughout their life span. In the present study, we attempted to elucidate how axolotls can specify limb type correctly during the regeneration process. We misexpressed Tbx5 in regenerating hindlimb blastema, and consequently a forelimb-like hindlimb regenerated from the hindlimb blastema. On the other hand, no change was observed in Tbx5-overexpressing forelimb blastema, and thus we considered that Tbx5 plays a key role in the specification of forelimb during the regeneration process of axolotl limbs. However, axolotls' fore- and hindlimbs have very similar structures except for the number of fingers, and it was very difficult to judge whether the forelimb-like regenerate was a true forelimb or merely a forelimb-like hindlimb. Therefore, in order to confirm our conclusion, we have to investigate other genes that are expressed differentially between fore- and hindlimbs in future experiments.

ISOLATION AND CHARACTERIZATION OF AXOLOTL NPDC-1 AND ITS EFFECTS ON RETINOIC ACID RECEPTOR SIGNALING

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Theodosiou, Maria; Monaghan, James R; Spencer, Michael L; Voss, S Randal; Noonan, Daniel J

2009-01-01

Retinoic acid, a key morphogen in early vertebrate development and tissue regeneration, mediates its effects through the binding of receptors that act as ligand-induced transcription factors. These binding events function to recruit an array of transcription co-regulatory proteins to specific gene promoters. One such co-regulatory protein, neuronal proliferation and differentiation control-1 (NPDC-1), is broadly expressed during mammalian development and functions as an in vitro repressor of retinoic acid receptor (RAR)-mediated transcription. To obtain comparative and developmental insights about NPDC-1 function, we cloned the axolotl (Ambystoma mexicanum) orthologue and measured transcript abundances among tissues sampled during the embryonic and juvenile phases of development, and also during spinal cord regeneration. Structurally, the axolotl orthologue of NPDC-1 retained sequence identity to mammalian sequences in all functional domains. Functionally, we observed that axolotl NPDC-1 mRNA expression peaked late in embryogenesis, with highest levels of expression occurring during the time of limb development, a process regulated by retinoic acid signaling. Also similar to what has been observed in mammals, axolotl NPDC-1 directly interacts with axolotl RAR, modulates axolotl RAR DNA binding, and represses cell proliferation and axolotl RAR-mediated gene transcription. These data justify axolotl as a model to further investigate NPDC-1 and its role in regulating retinoic acid signaling. PMID:17331771

A histological atlas of the tissues and organs of neotenic and metamorphosed axolotl.

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Demircan, Turan; İlhan, Ayşe Elif; Aytürk, Nilüfer; Yıldırım, Berna; Öztürk, Gürkan; Keskin, İlknur

2016-09-01

Axolotl (Ambystoma Mexicanum) has been emerging as a promising model in stem cell and regeneration researches due to its exceptional regenerative capacity. Although it represents lifelong lasting neoteny, induction to metamorphosis with thyroid hormones (THs) treatment advances the utilization of Axolotl in various studies. It has been reported that amphibians undergo anatomical and histological remodeling during metamorphosis and this transformation is crucial for adaptation to terrestrial conditions. However, there is no comprehensive histological investigation regarding the morphological alterations of Axolotl organs and tissues throughout the metamorphosis. Here, we reveal the histological differences or resemblances between the neotenic and metamorphic axolotl tissues. In order to examine structural features and cellular organization of Axolotl organs, we performed Hematoxylin & Eosin, Luxol-Fast blue, Masson's trichrome, Alcian blue, Orcein and Weigart's staining. Stained samples from brain, gallbladder, heart, intestine, liver, lung, muscle, skin, spleen, stomach, tail, tongue and vessel were analyzed under the light microscope. Our findings contribute to the validation of the link between newly acquired functions and structural changes of tissues and organs as observed in tail, skin, gallbladder and spleen. We believe that this descriptive work provides new insights for a better histological understanding of both neotenic and metamorphic Axolotl tissues. Copyright © 2016 Elsevier GmbH. All rights reserved.

Continuous growth of the motor system in the axolotl

International Nuclear Information System (INIS)

Holder, N.; Clarke, J.D.; Stephens, N.; Wilson, S.W.; Orsi, C.; Bloomer, T.; Tonge, D.A.

1991-01-01

During growth of the axolotl, motor neurons, and muscle fibres are added to the motor system. By double labelling neurons with tritiated thymidine and retrogradely transported HRP, we show that some motor neurons are born at postembryonic stages. Further analysis of motor neurons with the aid of HRP reveals this population of newly born cells relatively frequently in small (5-7 cm long) axolotls, but only rarely in large (7-13 cm long) axolotls. Evidence is presented that suggests that these immature cells are in the process of migrating from close to the ependyma out to the ventral horn. HRP transport also reveals growth cones of advancing axons within spinal nerves in animals up to 6 cm in length. Cell counts by light and electron microscopic methods show that muscle fibres are generated throughout larval life in the iliotibialis, a typical limb muscle. This analysis provides data consistent with the notion that new muscle fibres are added from a localised growth zone situated at the superficial edge of the muscle. These results are discussed in terms of the correlation between continuous growth of the motor system and the ability of the axolotl to functionally repair lesions to the peripheral nervous system

Transforming growth factor: beta signaling is essential for limb regeneration in axolotls.

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Mathieu Lévesque

2007-11-01

Full Text Available Axolotls (urodele amphibians have the unique ability, among vertebrates, to perfectly regenerate many parts of their body including limbs, tail, jaw and spinal cord following injury or amputation. The axolotl limb is the most widely used structure as an experimental model to study tissue regeneration. The process is well characterized, requiring multiple cellular and molecular mechanisms. The preparation phase represents the first part of the regeneration process which includes wound healing, cellular migration, dedifferentiation and proliferation. The redevelopment phase represents the second part when dedifferentiated cells stop proliferating and redifferentiate to give rise to all missing structures. In the axolotl, when a limb is amputated, the missing or wounded part is regenerated perfectly without scar formation between the stump and the regenerated structure. Multiple authors have recently highlighted the similarities between the early phases of mammalian wound healing and urodele limb regeneration. In mammals, one very important family of growth factors implicated in the control of almost all aspects of wound healing is the transforming growth factor-beta family (TGF-beta. In the present study, the full length sequence of the axolotl TGF-beta1 cDNA was isolated. The spatio-temporal expression pattern of TGF-beta1 in regenerating limbs shows that this gene is up-regulated during the preparation phase of regeneration. Our results also demonstrate the presence of multiple components of the TGF-beta signaling machinery in axolotl cells. By using a specific pharmacological inhibitor of TGF-beta type I receptor, SB-431542, we show that TGF-beta signaling is required for axolotl limb regeneration. Treatment of regenerating limbs with SB-431542 reveals that cellular proliferation during limb regeneration as well as the expression of genes directly dependent on TGF-beta signaling are down-regulated. These data directly implicate TGF

Detailed tail proteomic analysis of axolotl (Ambystoma mexicanum) using an mRNA-seq reference database.

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Demircan, Turan; Keskin, Ilknur; Dumlu, Seda Nilgün; Aytürk, Nilüfer; Avşaroğlu, Mahmut Erhan; Akgün, Emel; Öztürk, Gürkan; Baykal, Ahmet Tarık

2017-01-01

Salamander axolotl has been emerging as an important model for stem cell research due to its powerful regenerative capacity. Several advantages, such as the high capability of advanced tissue, organ, and appendages regeneration, promote axolotl as an ideal model system to extend our current understanding on the mechanisms of regeneration. Acknowledging the common molecular pathways between amphibians and mammals, there is a great potential to translate the messages from axolotl research to mammalian studies. However, the utilization of axolotl is hindered due to the lack of reference databases of genomic, transcriptomic, and proteomic data. Here, we introduce the proteome analysis of the axolotl tail section searched against an mRNA-seq database. We translated axolotl mRNA sequences to protein sequences and annotated these to process the LC-MS/MS data and identified 1001 nonredundant proteins. Functional classification of identified proteins was performed by gene ontology searches. The presence of some of the identified proteins was validated by in situ antibody labeling. Furthermore, we have analyzed the proteome expressional changes postamputation at three time points to evaluate the underlying mechanisms of the regeneration process. Taken together, this work expands the proteomics data of axolotl to contribute to its establishment as a fully utilized model. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ambiguities in the relationship between gonadal steroids and reproduction in axolotls (Ambystoma mexicanum).

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Eisthen, Heather L; Krause, Brianne Chung

2012-05-01

Axolotls (Ambystoma mexicanum) are aquatic salamanders that are widely used in research. Axolotls have been bred in laboratories for nearly 150 years, yet little is known about the basic biology of reproduction in these animals. We investigated the effects of changing day length, time of year, and food availability on levels of circulating estradiol and androgens in adult female and male axolotls, respectively. In addition, we examined the effects of these variables on the mass of ovaries, oviducts, and eggs in females and on mass of testes in males relative to each individual's body weight, to calculate a form of gonadosomatic index (GSI). In both sexes, GSI was not correlated with levels of circulating steroids. In female axolotls, estradiol levels were influenced by food availability, changes in day length, and season, even when animals were held at a constant temperature and day length was decorrelated with calendar date. In addition, the mass of ovaries, oviducts, and eggs varied seasonally, peaking in the winter months and declining during the summer months, even though our animals were not breeding and shedding eggs. In males, levels of androgens appeared to vary independently of external conditions, but GSI varied dramatically with changes in day length. These results suggest that reproduction in axolotls may vary seasonally, as it does in many other ambystomid species, although both male and female axolotls are capable of reproducing several times each year. The physiological basis of this ability remains enigmatic, given the indications of seasonality contained in our data. Copyright © 2012 Elsevier Inc. All rights reserved.

Highly efficient targeted mutagenesis in axolotl using Cas9 RNA-guided nuclease

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Flowers, G. Parker; Timberlake, Andrew T.; Mclean, Kaitlin C.; Monaghan, James R.; Crews, Craig M.

2014-01-01

Among tetrapods, only urodele salamanders, such as the axolotl Ambystoma mexicanum, can completely regenerate limbs as adults. The mystery of why salamanders, but not other animals, possess this ability has for generations captivated scientists seeking to induce this phenomenon in other vertebrates. Although many recent advances in molecular biology have allowed limb regeneration and tissue repair in the axolotl to be investigated in increasing detail, the molecular toolkit for the study of this process has been limited. Here, we report that the CRISPR-Cas9 RNA-guided nuclease system can efficiently create mutations at targeted sites within the axolotl genome. We identify individual animals treated with RNA-guided nucleases that have mutation frequencies close to 100% at targeted sites. We employ this technique to completely functionally ablate EGFP expression in transgenic animals and recapitulate developmental phenotypes produced by loss of the conserved gene brachyury. Thus, this advance allows a reverse genetic approach in the axolotl and will undoubtedly provide invaluable insight into the mechanisms of salamanders' unique regenerative ability. PMID:24764077

Experimentally induced metamorphosis in axolotls reduces regenerative rate and fidelity

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Stier, Adrian C.; Michonneau, François; Smith, Matthew D.; Pasch, Bret; Maden, Malcolm

2014-01-01

Abstract While most tetrapods are unable to regenerate severed body parts, amphibians display a remarkable ability to regenerate an array of structures. Frogs can regenerate appendages as larva, but they lose this ability around metamorphosis. In contrast, salamanders regenerate appendages as larva, juveniles, and adults. However, the extent to which fundamental traits (e.g., metamorphosis, body size, aging, etc.) restrict regenerative ability remains contentious. Here we utilize the ability of normally paedomorphic adult axolotls (Ambystoma mexicanum) to undergo induced metamorphosis by thyroxine exposure to test how metamorphosis and body size affects regeneration in age‐matched paedomorphic and metamorphic individuals. We show that body size does not affect regeneration in adult axolotls, but metamorphosis causes a twofold reduction in regeneration rate, and lead to carpal and digit malformations. Furthermore, we find evidence that metamorphic blastemal cells may take longer to traverse the cell cycle and display a lower proliferative rate. This study identifies the axolotl as a powerful system to study how metamorphosis restricts regeneration independently of developmental stage, body size, and age; and more broadly how metamorphosis affects tissue‐specific changes. PMID:27499857

Esterases activity in the axolotl Ambystoma mexicanum exposed to chlorpyrifos and its implication to motor activity.

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Robles-Mendoza, Cecilia; Zúñiga-Lagunes, Sebastian R; Ponce de León-Hill, Claudia A; Hernández-Soto, Jesús; Vanegas-Pérez, Cecilia

2011-10-01

The axolotl Ambystoma mexicanum is a neotenic salamander considered a good biological model due to its ability to regenerate limbs, tail, brain and heart cells. Nevertheless, severe reduction of A. mexicanum wild populations in the lacustrine area of Xochimilco, the natural habitat of the axolotl, could be related to several environmental pressures as the presence of organophosphate pesticides (OPPs), intensively applied in agricultural activities in Xochimilco. Thus the aim of this study was to evaluate the effect of environmentally realistic chlorpyrifos (CPF) concentrations, a OPP commonly used in this zone, on esterases activity (acetylcholinesterase and carboxylesterase) and bioconcentration of CPF and to relate them with the motor activity of A. mexicanum juveniles. Axolotls were exposed 48 h to 0.05 and 0.1mg CPF/L, and the responses were evaluated at the end of the CPF exposure. Results suggest that CPF is bioconcentrated into axolotls and that the CPF internal concentrations are related with the observed inhibition activity of AChE (>50%) and CbE (≈ 50%). CPF concentration responsible of the inhibition of the 50% of AChE activity (IC50) was estimated in 0.04 mg CPF/L; however IC50 for CbE activity was not possible to calculate since inhibition levels were lower than 50%, results that suggest a higher resistance of CbE enzymatic activity to CPF. However, motor activity was a more sensitive endpoint to CPF poisoning since time that axolotls spent active and walking, frequency and speed of swimming, frequency of prey attack were reduced >90% of control groups. The motor activity alterations in the axolotl could be related with the registered esterases inhibition. Thus important alterations on axolotls were identified even at short time and low concentrations of CPF exposure. Also, it was possible to link biochemical responses as esterases activity with higher levels of biological organization as behavior. This study provides tools for the regulation of the

Visualisation of axolotl blastema cells and pig endothelial progenitor cells using very small super paramagnetic iron oxide particles in MRI: A technique with applications for non invasive visualisation of regenerative processes

DEFF Research Database (Denmark)

Lauridsen, Henrik; Kjær, N.B.; Bek, Maria

oxide particles (VSOP) in animal cells enable non invasive cell tracking using magnetic resonance imaging (MRI) and can prove useful, when visualising regenerative processes. This study examines the possibility of labelling limited numbers of axolotl blastema cells (aBC) and pig endothelial progenitor...... implanted in live axolotl tail and dead porcine heart, respectively. Cellular iron uptake was determined using inductively coupled plasma optical emission spectrometry (ICP-OES). Results: T2*-weighted 2D gradient-echo sequences on samples of 10˄5 cells yielded at significant linear correlations between...

Evidence for balancing selection at the DAB locus in the axolotl, Ambystoma mexicanum.

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Richman, A D; Herrera, G; Reynoso, V H; Méndez, G; Zambrano, L

2007-12-01

The axolotl (Ambystoma mexicanum) has been characterized as immunodeficient, and the absence of major histocompatibility complex (MHC) class II polymorphism has been cited as a possible explanation. Here we present evidence for considerable allelic polymorphism at the MHC class II DAB locus for a sample of wild-caught axolotls. Evidence that these sequences are the product of balancing selection for disease resistance is discussed.

Injection of an antibody against a p21 c-Ha-ras protein inhibits cleavage in axolotl eggs.

OpenAIRE

Baltus, E; Hanocq-Quertier, J; Hanocq, F; Brachet, J

1988-01-01

The presence of a ras protein was demonstrated in cleaving axolotl eggs by selective immunoprecipitation with a polyclonal antibody against a peptide encoded by the c-Ha-ras oncogene, cellular homolog of the v-Ha-ras oncogene of Harvey rat sarcoma virus. Injection of this antibody into axolotl oocytes subjected to progesterone treatment does not prevent meiotic maturation. Injection of the same antibody into a blastomere of axolotl eggs at the 2- or 4-cell stage causes cleavage arrest in the ...

Data on chemical activation of Wnt/β-catenin during axolotl limb regeneration

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Sabina Wischin

2017-04-01

Full Text Available Limb amputation in axolotls was performed to obtain data demonstrating that a chemical agonist of Wnt (int-related protein/β-catenin signalling can have a role in axolotl limb regeneration (Wischin et al., 2017 [1]. The data revealed that active β-catenin protein was present during limb regeneration in some Leydig cells in the epithelium; after the chemical treatment, it was observed in more Leydig cells. In addition, the chemical agonist of Wnt generated distinct limb malformation.

Efficient gene knockin in axolotl and its use to test the role of satellite cells in limb regeneration.

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Fei, Ji-Feng; Schuez, Maritta; Knapp, Dunja; Taniguchi, Yuka; Drechsel, David N; Tanaka, Elly M

2017-11-21

Salamanders exhibit extensive regenerative capacities and serve as a unique model in regeneration research. However, due to the lack of targeted gene knockin approaches, it has been difficult to label and manipulate some of the cell populations that are crucial for understanding the mechanisms underlying regeneration. Here we have established highly efficient gene knockin approaches in the axolotl ( Ambystoma mexicanum ) based on the CRISPR/Cas9 technology. Using a homology-independent method, we successfully inserted both the Cherry reporter gene and a larger membrane-tagged Cherry-ER T2 -Cre-ER T2 (∼5-kb) cassette into axolotl Sox2 and Pax7 genomic loci. Depending on the size of the DNA fragments for integration, 5-15% of the F0 transgenic axolotl are positive for the transgene. Using these techniques, we have labeled and traced the PAX7-positive satellite cells as a major source contributing to myogenesis during axolotl limb regeneration. Our work brings a key genetic tool to molecular and cellular studies of axolotl regeneration.

Transgenesis in axolotl (Ambystoma mexicanum).

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Khattak, Shahryar; Tanaka, Elly M

2015-01-01

Transgenic animals have been indispensable in elucidating and deciphering mechanisms underlying various biological phenomena. In regeneration, transgenic animals expressing fluorescent protein genes have been crucial for identifying the source cells for regeneration and the mechanism of blastema formation. Animals are usually generated by manipulating their genome using various techniques at/in one cell embryo/fertilized egg stage. Here, we describe the generation of germline transgenic axolotls (Ambystoma mexicanum) using the I-SceI meganuclease and Tol2 transposase.

Proteinaceous Pheromone Homologs Identified from the Cloacal Gland Transcriptome of a Male Axolotl, Ambystoma mexicanum.

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Kevin W Hall

Full Text Available Pheromones play an important role in modifying vertebrate behavior, especially during courtship and mating. Courtship behavior in urodele amphibians often includes female exposure to secretions from the cloacal gland, as well as other scent glands. The first vertebrate proteinaceous pheromone discovered, the decapeptide sodefrin, is a female attracting pheromone secreted by the cloacal gland of male Cynops pyrrhogaster. Other proteinaceous pheromones in salamanders have been shown to elicit responses from females towards conspecific males. The presence and levels of expression of proteinaceous pheromones have not been identified in the family Ambystomatidae, which includes several important research models. The objective of this research was therefore to identify putative proteinaceous pheromones from male axolotls, Ambystoma mexicanum, as well as their relative expression levels. The results indicate that axolotls possess two different forms of sodefrin precursor-like factor (alpha and beta, as well as a putative ortholog of plethodontid modulating factor. The beta form of sodefrin precursor-like factor was amongst the most highly expressed transcripts within the cloacal gland. The ortholog of plethodontid modulating factor was expressed at a level equivalent to the beta sodefrin precursor-like factor. The results are from a single male axolotl; therefore, we are unable to assess how representative our results may be. Nevertheless, the presence of these highly expressed proteinaceous pheromones suggests that male axolotls use multiple chemical cues to attract female conspecifics. Behavioral assays would indicate whether the putative protein pheromones elicit courtship activity from female axolotls.

Proteinaceous Pheromone Homologs Identified from the Cloacal Gland Transcriptome of a Male Axolotl, Ambystoma mexicanum.

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Hall, Kevin W; Eisthen, Heather L; Williams, Barry L

2016-01-01

Pheromones play an important role in modifying vertebrate behavior, especially during courtship and mating. Courtship behavior in urodele amphibians often includes female exposure to secretions from the cloacal gland, as well as other scent glands. The first vertebrate proteinaceous pheromone discovered, the decapeptide sodefrin, is a female attracting pheromone secreted by the cloacal gland of male Cynops pyrrhogaster. Other proteinaceous pheromones in salamanders have been shown to elicit responses from females towards conspecific males. The presence and levels of expression of proteinaceous pheromones have not been identified in the family Ambystomatidae, which includes several important research models. The objective of this research was therefore to identify putative proteinaceous pheromones from male axolotls, Ambystoma mexicanum, as well as their relative expression levels. The results indicate that axolotls possess two different forms of sodefrin precursor-like factor (alpha and beta), as well as a putative ortholog of plethodontid modulating factor. The beta form of sodefrin precursor-like factor was amongst the most highly expressed transcripts within the cloacal gland. The ortholog of plethodontid modulating factor was expressed at a level equivalent to the beta sodefrin precursor-like factor. The results are from a single male axolotl; therefore, we are unable to assess how representative our results may be. Nevertheless, the presence of these highly expressed proteinaceous pheromones suggests that male axolotls use multiple chemical cues to attract female conspecifics. Behavioral assays would indicate whether the putative protein pheromones elicit courtship activity from female axolotls.

Dual embryonic origin of the hyobranchial apparatus in the Mexican axolotl (Ambystoma mexicanum).

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Davidian, Asya; Malashichev, Yegor

2013-01-01

Traditionally, the cartilaginous viscerocranium of vertebrates is considered as neural crest (NC)-derived. Morphological work carried out on amphibian embryos in the first half of the XX century suggested potentially mesodermal origin for some hyobranchial elements. Since then, the embryonic sources of the hyobranchial apparatus in amphibians has not been investigated due to lack of an appropriate long-term labelling system. We performed homotopic transplantations of neural folds along with the majority of cells of the presumptive NC, and/or fragments of the head lateral plate mesoderm (LPM) from transgenic GFP+ into white embryos. In these experiments, the NC-derived GFP+ cells contributed to all hyobranchial elements, except for basibranchial 2, whereas the grafting of GFP+ head mesoderm led to a reverse labelling result. The grafting of only the most ventral part of the head LPM resulted in marking of the basibranchial 2 and the heart myocardium, implying their origin from a common mesodermal region. This is the first evidence of contribution of LPM of the head to cranial elements in any vertebrate. If compared to fish, birds, and mammals, in which all branchial skeletal elements are NC-derived, the axolotl (probably this is true for all amphibians) demonstrates an evolutionary deviation, in which the head LPM replaces NC cells in a hyobranchial element. This implies that cells of different embryonic origin may have the same developmental program, leading to the formation of identical (homologous) elements of the skeleton.

Organophosphorus pesticides effect on early stages of the axolotl Ambystoma mexicanum (Amphibia: Caudata).

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Robles-Mendoza, C; García-Basilio, C; Cram-Heydrich, S; Hernández-Quiroz, M; Vanegas-Pérez, C

2009-02-01

Ambystoma mexicanum is an endemic salamander of Xochimilco, a wetland of the basin of Mexico valley. Nowadays, axolotl populations are decreasing due environmental stressors. Particularly, studies about organophosphorus pesticides (OPPs; i.e. chlorpyrifos and malathion) toxicity are of great importance due to their intensive use in agricultural activities in Xochimilco. Thus, the aim of this study was to evaluate under controlled conditions the toxicity of chlorpyrifos (CPF) and malathion (MLT) on embryos and larvae (stage 44 and 54) of A. mexicanum. Embryos and larvae were exposure 96h from 0.5 to 3mg CPFL(-1) and from 10 to 30mg MLTL(-1) in independent tests. Embryos at the end of this period were maintained 9d without pesticide in order to identify possible recuperation. Differences obtained in mortality, hatching success, development, morphological abnormalities, behaviour and activity, suggest that toxicity of CPF and MLT differs in embryos and larval stages. Embryos were less sensitive to OPPs acute exposure than axolotl larvae; additionally, toxicity of CPF in larval stages was greater than MLT. On the other hand, data obtained in axolotl embryos during the period of recuperation to CPF in particular as delay and inhibition of development, malformations and success of hatching, indicated that these responses turned out more sensitive than mortality. This study allowed to identify the toxicological potential of OPPs on early developmental stages of A. mexicanum and it is a valuable contribution for the future management of the axolotl wild population.

Expression of Msx genes in regenerating and developing limbs of axolotl.

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Koshiba, K; Kuroiwa, A; Yamamoto, H; Tamura, K; Ide, H

1998-12-15

Msx genes, homeobox-containing genes, have been isolated as homologues of the Drosophila msh gene and are thought to play important roles in the development of chick or mouse limb buds. We isolated two Msx genes, Msx1 and Msx2, from regenerating blastemas of axolotl limbs and examined their expression patterns using Northern blot and whole mount in situ hybridization during regeneration and development. Northern blot analysis revealed that the expression level of both Msx genes increased during limb regeneration. The Msx2 expression level increased in the blastema at the early bud stage, and Msx1 expression level increased at the late bud stage. Whole mount in situ hybridization revealed that Msx2 was expressed in the distal mesenchyme and Msx1 in the entire mesenchyme of the blastema at the late bud stage. In the developing limb bud, Msx1 was expressed in the entire mesenchyme, while Msx2 was expressed in the distal and peripheral mesenchyme. The expression patterns of Msx genes in the blastemas and limb buds of the axolotl were different from those reported for chick or mouse limb buds. These expression patterns of axolotl Msx genes are discussed in relation to the blastema or limb bud morphology and their possible roles in limb patterning.

Novel axolotl cardiac function analysis method using magnetic resonance imaging

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Sanches, Pedro Gomes; Op 't Veld, Roel C.; de Graaf, Wolter; Strijkers, Gustav J.; Grüll, Holger

2017-01-01

The salamander axolotl is capable of complete regeneration of amputated heart tissue. However, non-invasive imaging tools for assessing its cardiac function were so far not employed. In this study, cardiac magnetic resonance imaging is introduced as a non-invasive technique to image heart function

Novel axolotl cardiac function analysis method using magnetic resonance imaging

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Sanches, P.G.; Op ‘t Veld, R.C.; de Graaf, W.; Strijkers, G.J.; Grüll, H.

2017-01-01

The salamander axolotl is capable of complete regeneration of amputated heart tissue. However, non-invasive imaging tools for assessing its cardiac function were so far not employed. In this study, cardiac magnetic resonance imaging is introduced as a noninvasive technique to image heart function of

Comparative RNA-seq analysis in the unsequenced axolotl: the oncogene burst highlights early gene expression in the blastema.

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Ron Stewart

Full Text Available The salamander has the remarkable ability to regenerate its limb after amputation. Cells at the site of amputation form a blastema and then proliferate and differentiate to regrow the limb. To better understand this process, we performed deep RNA sequencing of the blastema over a time course in the axolotl, a species whose genome has not been sequenced. Using a novel comparative approach to analyzing RNA-seq data, we characterized the transcriptional dynamics of the regenerating axolotl limb with respect to the human gene set. This approach involved de novo assembly of axolotl transcripts, RNA-seq transcript quantification without a reference genome, and transformation of abundances from axolotl contigs to human genes. We found a prominent burst in oncogene expression during the first day and blastemal/limb bud genes peaking at 7 to 14 days. In addition, we found that limb patterning genes, SALL genes, and genes involved in angiogenesis, wound healing, defense/immunity, and bone development are enriched during blastema formation and development. Finally, we identified a category of genes with no prior literature support for limb regeneration that are candidates for further evaluation based on their expression pattern during the regenerative process.

Ultrastructure of the renal juxtaglomerular complex and peripolar cells in the axolotl (Ambystoma mexicanum) and toad (Bufo marinus).

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Hanner, R H; Ryan, G B

1980-01-01

Renal juxtaglomerular regions were examined in the axolotl (Ambystoma mexicanum and toad (Bufo marinus). Prominent granulated peripolar epithelial cells were found surrounding the origin of the glomerular tuft in the axolotl. These cells resembled the peripolar cells recently discovered in mammalian species. They contained multiple electron-dense cytoplasmic granules, some of which showed a paracrystalline substructure and signs of exocytoxic activity. Such cells were difficult to find and smaller in the toad. In contrast, granulated juxtaglomerular arteriolar myoephithelial cells were much more readily found and larger in the toad than in the axolotl. No consistent differences were noted in juxtaglomerular cells or their granules in response to changes in environmental chloride concentration. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:7410189

Microarray Analysis of microRNA Expression during Axolotl Limb Regeneration

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Holman, Edna C.; Campbell, Leah J.; Hines, John; Crews, Craig M.

2012-01-01

Among vertebrates, salamanders stand out for their remarkable capacity to quickly regrow a myriad of tissues and organs after injury or amputation. The limb regeneration process in axolotls (Ambystoma mexicanum) has been well studied for decades at the cell-tissue level. While several developmental genes are known to be reactivated during this epimorphic process, less is known about the role of microRNAs in urodele amphibian limb regeneration. Given the compelling evidence that many microRNAs tightly regulate cell fate and morphogenetic processes through development and adulthood by modulating the expression (or re-expression) of developmental genes, we investigated the possibility that microRNA levels change during limb regeneration. Using two different microarray platforms to compare the axolotl microRNA expression between mid-bud limb regenerating blastemas and non-regenerating stump tissues, we found that miR-21 was overexpressed in mid-bud blastemas compared to stump tissue. Mature A. mexicanum (“Amex”) miR-21 was detected in axolotl RNA by Northern blot and differential expression of Amex-miR-21 in blastema versus stump was confirmed by quantitative RT-PCR. We identified the Amex Jagged1 as a putative target gene for miR-21 during salamander limb regeneration. We cloned the full length 3′UTR of Amex-Jag1, and our in vitro assays demonstrated that its single miR-21 target recognition site is functional and essential for the response of the Jagged1 gene to miR-21 levels. Our findings pave the road for advanced in vivo functional assays aimed to clarify how microRNAs such as miR-21, often linked to pathogenic cell growth, might be modulating the redeployment of developmental genes such as Jagged1 during regenerative processes. PMID:23028429

Microarray analysis of microRNA expression during axolotl limb regeneration.

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Edna C Holman

Full Text Available Among vertebrates, salamanders stand out for their remarkable capacity to quickly regrow a myriad of tissues and organs after injury or amputation. The limb regeneration process in axolotls (Ambystoma mexicanum has been well studied for decades at the cell-tissue level. While several developmental genes are known to be reactivated during this epimorphic process, less is known about the role of microRNAs in urodele amphibian limb regeneration. Given the compelling evidence that many microRNAs tightly regulate cell fate and morphogenetic processes through development and adulthood by modulating the expression (or re-expression of developmental genes, we investigated the possibility that microRNA levels change during limb regeneration. Using two different microarray platforms to compare the axolotl microRNA expression between mid-bud limb regenerating blastemas and non-regenerating stump tissues, we found that miR-21 was overexpressed in mid-bud blastemas compared to stump tissue. Mature A. mexicanum ("Amex" miR-21 was detected in axolotl RNA by Northern blot and differential expression of Amex-miR-21 in blastema versus stump was confirmed by quantitative RT-PCR. We identified the Amex Jagged1 as a putative target gene for miR-21 during salamander limb regeneration. We cloned the full length 3'UTR of Amex-Jag1, and our in vitro assays demonstrated that its single miR-21 target recognition site is functional and essential for the response of the Jagged1 gene to miR-21 levels. Our findings pave the road for advanced in vivo functional assays aimed to clarify how microRNAs such as miR-21, often linked to pathogenic cell growth, might be modulating the redeployment of developmental genes such as Jagged1 during regenerative processes.

Network based transcription factor analysis of regenerating axolotl limbs

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Cameron Jo Ann

2011-03-01

Full Text Available Abstract Background Studies on amphibian limb regeneration began in the early 1700's but we still do not completely understand the cellular and molecular events of this unique process. Understanding a complex biological process such as limb regeneration is more complicated than the knowledge of the individual genes or proteins involved. Here we followed a systems biology approach in an effort to construct the networks and pathways of protein interactions involved in formation of the accumulation blastema in regenerating axolotl limbs. Results We used the human orthologs of proteins previously identified by our research team as bait to identify the transcription factor (TF pathways and networks that regulate blastema formation in amputated axolotl limbs. The five most connected factors, c-Myc, SP1, HNF4A, ESR1 and p53 regulate ~50% of the proteins in our data. Among these, c-Myc and SP1 regulate 36.2% of the proteins. c-Myc was the most highly connected TF (71 targets. Network analysis showed that TGF-β1 and fibronectin (FN lead to the activation of these TFs. We found that other TFs known to be involved in epigenetic reprogramming, such as Klf4, Oct4, and Lin28 are also connected to c-Myc and SP1. Conclusions Our study provides a systems biology approach to how different molecular entities inter-connect with each other during the formation of an accumulation blastema in regenerating axolotl limbs. This approach provides an in silico methodology to identify proteins that are not detected by experimental methods such as proteomics but are potentially important to blastema formation. We found that the TFs, c-Myc and SP1 and their target genes could potentially play a central role in limb regeneration. Systems biology has the potential to map out numerous other pathways that are crucial to blastema formation in regeneration-competent limbs, to compare these to the pathways that characterize regeneration-deficient limbs and finally, to identify stem

Neural crest does not contribute to the neck and shoulder in the axolotl (Ambystoma mexicanum).

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Epperlein, Hans-Henning; Khattak, Shahryar; Knapp, Dunja; Tanaka, Elly M; Malashichev, Yegor B

2012-01-01

A major step during the evolution of tetrapods was their transition from water to land. This process involved the reduction or complete loss of the dermal bones that made up connections to the skull and a concomitant enlargement of the endochondral shoulder girdle. In the mouse the latter is derived from three separate embryonic sources: lateral plate mesoderm, somites, and neural crest. The neural crest was suggested to sustain the muscle attachments. How this complex composition of the endochondral shoulder girdle arose during evolution and whether it is shared by all tetrapods is unknown. Salamanders that lack dermal bone within their shoulder girdle were of special interest for a possible contribution of the neural crest to the endochondral elements and muscle attachment sites, and we therefore studied them in this context. We grafted neural crest from GFP+ fluorescent transgenic axolotl (Ambystoma mexicanum) donor embryos into white (d/d) axolotl hosts and followed the presence of neural crest cells within the cartilage of the shoulder girdle and the connective tissue of muscle attachment sites of the neck-shoulder region. Strikingly, neural crest cells did not contribute to any part of the endochondral shoulder girdle or to the connective tissue at muscle attachment sites in axolotl. Our results in axolotl suggest that neural crest does not serve a general function in vertebrate shoulder muscle attachment sites as predicted by the "muscle scaffold theory," and that it is not necessary to maintain connectivity of the endochondral shoulder girdle to the skull. Our data support the possibility that the contribution of the neural crest to the endochondral shoulder girdle, which is observed in the mouse, arose de novo in mammals as a developmental basis for their skeletal synapomorphies. This further supports the hypothesis of an increased neural crest diversification during vertebrate evolution.

Neural crest does not contribute to the neck and shoulder in the axolotl (Ambystoma mexicanum.

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Hans-Henning Epperlein

Full Text Available BACKGROUND: A major step during the evolution of tetrapods was their transition from water to land. This process involved the reduction or complete loss of the dermal bones that made up connections to the skull and a concomitant enlargement of the endochondral shoulder girdle. In the mouse the latter is derived from three separate embryonic sources: lateral plate mesoderm, somites, and neural crest. The neural crest was suggested to sustain the muscle attachments. How this complex composition of the endochondral shoulder girdle arose during evolution and whether it is shared by all tetrapods is unknown. Salamanders that lack dermal bone within their shoulder girdle were of special interest for a possible contribution of the neural crest to the endochondral elements and muscle attachment sites, and we therefore studied them in this context. RESULTS: We grafted neural crest from GFP+ fluorescent transgenic axolotl (Ambystoma mexicanum donor embryos into white (d/d axolotl hosts and followed the presence of neural crest cells within the cartilage of the shoulder girdle and the connective tissue of muscle attachment sites of the neck-shoulder region. Strikingly, neural crest cells did not contribute to any part of the endochondral shoulder girdle or to the connective tissue at muscle attachment sites in axolotl. CONCLUSIONS: Our results in axolotl suggest that neural crest does not serve a general function in vertebrate shoulder muscle attachment sites as predicted by the "muscle scaffold theory," and that it is not necessary to maintain connectivity of the endochondral shoulder girdle to the skull. Our data support the possibility that the contribution of the neural crest to the endochondral shoulder girdle, which is observed in the mouse, arose de novo in mammals as a developmental basis for their skeletal synapomorphies. This further supports the hypothesis of an increased neural crest diversification during vertebrate evolution.

Expression of Msx-2 during development, regeneration, and wound healing in axolotl limbs.

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Carlson, M R; Bryant, S V; Gardiner, D M

1998-12-15

Msx genes are transcription factors that are expressed during embryogenesis of developing appendages in regions of epithelial-mesenchymal interactions. Various lines of evidence indicate that these genes function to maintain embryonic tissues in an undifferentiated, proliferative state. We have identified the axolotl homolog of Msx-2, and investigated its expression during limb development, limb regeneration, and wound healing. As in limb buds of higher vertebrates, axolotl Msx-2 is expressed in the apical epidermis and mesenchyme; however, its expression domain is more extensive, reflecting the broader region of the apical epidermal cap in amphibians. Msx-2 expression is downregulated at late stages of limb development, but is reexpressed within one hour after limb amputation. Msx-2 is also reexpressed during wound healing, and may be essential in the early stages of initiation of the limb regeneration cascade.

Analysis of embryonic development in the unsequenced axolotl: waves of transcriptomic upheaval and stability

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Jiang, Peng; Nelson, Jeffrey D.; Leng, Ning; Collins, Michael; Swanson, Scott; Dewey, Colin N.; Thomson, James A.; Stewart, Ron

2016-01-01

The axolotl (Ambystoma mexicanum) has long been the subject of biological research, primarily owing to its outstanding regenerative capabilities. However, the gene expression programs governing its embryonic development are particularly underexplored, especially when compared to other amphibian model species. Therefore, we performed whole transcriptome polyA+ RNA sequencing experiments on 17 stages of embryonic development. As the axolotl genome is unsequenced and its gene annotation is incomplete, we built de novo transcriptome assemblies for each stage and garnered functional annotation by comparing expressed contigs with known genes in other organisms. In evaluating the number of differentially expressed genes over time, we identify three waves of substantial transcriptome upheaval each followed by a period of relative transcriptome stability. The first wave of upheaval is between the one and two cell stage. We show that the number of differentially expressed genes per unit time is higher between the one and two cell stage than it is across the mid-blastula transition (MBT), the period of zygotic genome activation. We use total RNA sequencing to demonstrate that the vast majority of genes with increasing polyA+ signal between the one and two cell stage result from polyadenylation rather than de novo transcription. The first stable phase begins after the two cell stage and continues until the mid-blastula transition, corresponding with the pre-MBT phase of transcriptional quiescence in amphibian development. Following this is a peak of differential gene expression corresponding with the activation of the zygotic genome and a phase of transcriptomic stability from stages 9 to 11. We observe a third wave of transcriptomic change between stages 11 and 14, followed by a final stable period. The last two stable phases have not been documented in amphibians previously and correspond to times of major morphogenic change in the axolotl embryo: gastrulation and

Hibridez y metamorfosis en Juan Villoro: el universo mágico-mitológico del ajolote

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An Van Hecke

2014-06-01

This study focuses on the symbolic meanings of the axolotl in Juan Villoro’s novel Materia dispuesta and the way the author approaches the concept of identity from both, the adolescent protagonist and Mexicans in general. This novel will be read in light of Roger Bartra’s essay, La jaula de la melancolía. Bartra uses the metaphor of the axolotl to analyse the concept of metamorphosis in the Mexican identity. Thereafter, Villoro’s novel will be compared with Julio Cortazar’s short story “Axolotl”, and Octavio Paz’s poem “Salamandra”. This comparison will allow to amplify the perspective and deepen the analysis of this hybrid animal by Villoro. The study of the axolotl demonstrates that Villoro revives the ancient aztec mythology about this amphibian, that was the representation of the god Xolotl, and that he introduces at the same time new meanings. It is in that combination of both perspectives that the richness of Villoro’s literary universe will be revealed.

Linking vertebral number to performance of aquatic escape responses in the axolotl (Ambystoma mexicanum).

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Ackerly, Kerri L; Ward, Andrea B

2015-12-01

Environmental conditions during early development in ectothermic vertebrates can lead to variation in vertebral number among individuals of the same species. It is often seen that individuals of a species raised at cooler temperatures have more vertebrae than individuals raised at warmer temperatures, although the functional consequences of this variation in vertebral number on swimming performance are relatively unclear. To investigate this relationship, we tested how vertebral number in axolotls (Ambystoma mexicanum) affected performance of aquatic escape responses (C-starts). Axolotls were reared at four temperatures (12-24°C) encompassing their natural thermal range and then transitioned to a mean temperature (18°C) three months before C-starts were recorded. Our results showed variation in vertebral number, but that variation was not significantly affected by developmental temperature. C-start performance among axolotls was significantly correlated with caudal vertebral number, and individuals with more caudal vertebrae were able to achieve greater curvature more quickly during their responses than individuals with fewer vertebrae. However, our results show that these individuals did not achieve greater displacements or velocities, and that developmental temperature did not have any effect on C-start performance. We highlight that the most important aspects of escape swim performance (i.e., how far individuals get from a threat and how quickly they move the most important parts of the body away from that threat) are consistent across individuals regardless of developmental temperature and morphological variation. Copyright © 2015 Elsevier GmbH. All rights reserved.

Axolotl cells and tissues enhances cutaneous wound healing in mice

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DEMIRCAN, Turan; KESKIN, Ilknur; GUNAL, Yalcin; ILHAN, Ayse Elif; KOLBASI, Bircan; OZTURK, Gurkan

2017-01-01

Adult mammalian skin wound repair is defective due to loss of the regulation in balancing the complete epithelial regeneration and excessive connective tissue production, and this repair process commonly results in scar tissue formation. However, unlike mammals, adult salamanders repair the wounds by regeneration compared to scarring. To elucidate the healing capability of a salamander, Axolotl, in a different species, here we addressed this question by treating the wounds in mice with Axolot...

Molecular cloning, sequence analysis and phylogeny of first caudata g-type lysozyme in axolotl (Ambystoma mexicanum).

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Yu, Haining; Gao, Jiuxiang; Lu, Yiling; Guang, Huijuan; Cai, Shasha; Zhang, Songyan; Wang, Yipeng

2013-11-01

Lysozymes are key proteins that play important roles in innate immune defense in many animal phyla by breaking down the bacterial cell-walls. In this study, we report the molecular cloning, sequence analysis and phylogeny of the first caudate amphibian g-lysozyme: a full-length spleen cDNA library from axolotl (Ambystoma mexicanum). A goose-type (g-lysozyme) EST was identified and the full-length cDNA was obtained using RACE-PCR. The axolotl g-lysozyme sequence represents an open reading frame for a putative signal peptide and the mature protein composed of 184 amino acids. The calculated molecular mass and the theoretical isoelectric point (pl) of this mature protein are 21523.0 Da and 4.37, respectively. Expression of g-lysozyme mRNA is predominantly found in skin, with lower levels in spleen, liver, muscle, and lung. Phylogenetic analysis revealed that caudate amphibian g-lysozyme had distinct evolution pattern for being juxtaposed with not only anura amphibian, but also with the fish, bird and mammal. Although the first complete cDNA sequence for caudate amphibian g-lysozyme is reported in the present study, clones encoding axolotl's other functional immune molecules in the full-length cDNA library will have to be further sequenced to gain insight into the fundamental aspects of antibacterial mechanisms in caudate.

BMP-2 functions independently of SHH signaling and triggers cell condensation and apoptosis in regenerating axolotl limbs

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Finnson Kenneth

2010-02-01

Full Text Available Abstract Background Axolotls have the unique ability, among vertebrates, to perfectly regenerate complex body parts, such as limbs, after amputation. In addition, axolotls pattern developing and regenerating autopods from the anterior to posterior axis instead of posterior to anterior like all tetrapods studied to date. Sonic hedgehog is important in establishing this anterior-posterior axis of limbs in all tetrapods including axolotls. Interestingly, its expression is conserved (to the posterior side of limb buds and blastemas in axolotl limbs as in other tetrapods. It has been suggested that BMP-2 may be the secondary mediator of sonic hedgehog, although there is mounting evidence to the contrary in mice. Since BMP-2 expression is on the anterior portion of developing and regenerating limbs prior to digit patterning, opposite to the expression of sonic hedgehog, we examined whether BMP-2 expression was dependent on sonic hedgehog signaling and whether it affects patterning of the autopod during regeneration. Results The expression of BMP-2 and SOX-9 in developing and regenerating axolotl limbs corresponded to the first digits forming in the anterior portion of the autopods. The inhibition of sonic hedgehog signaling with cyclopamine caused hypomorphic limbs (during development and regeneration but did not affect the expression of BMP-2 and SOX-9. Overexpression of BMP-2 in regenerating limbs caused a loss of digits. Overexpression of Noggin (BMP inhibitor in regenerating limbs also resulted in a loss of digits. Histological analysis indicated that the loss due to BMP-2 overexpression was the result of increased cell condensation and apoptosis while the loss caused by Noggin was due to a decrease in cell division. Conclusion The expression of BMP-2 and its target SOX-9 was independent of sonic hedgehog signaling in developing and regenerating limbs. Their expression correlated with chondrogenesis and the appearance of skeletal elements has

Multiple regeneration from axolotl limb stumps bearing cross-transplanted minced muscle regenerates : brief note

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Carlson, Bruce M.

Flexor and extensor muscles in the upper arms of axolotls were minced and cross-transplanted. The limbs were amputated 5 and 30 days after mincing. In each experiment a high percentage of the regenerates consisted of multiple limbs. This demonstrates that the morphogenetic information which produces

Comparative Analysis of Cartilage Marker Gene Expression Patterns during Axolotl and Xenopus Limb Regeneration.

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Kazumasa Mitogawa

Full Text Available Axolotls (Ambystoma mexicanum can completely regenerate lost limbs, whereas Xenopus laevis frogs cannot. During limb regeneration, a blastema is first formed at the amputation plane. It is thought that this regeneration blastema forms a limb by mechanisms similar to those of a developing embryonic limb bud. Furthermore, Xenopus laevis frogs can form a blastema after amputation; however, the blastema results in a terminal cone-shaped cartilaginous structure called a "spike." The causes of this patterning defect in Xenopus frog limb regeneration were explored. We hypothesized that differences in chondrogenesis may underlie the patterning defect. Thus, we focused on chondrogenesis. Chondrogenesis marker genes, type I and type II collagen, were compared in regenerative and nonregenerative environments. There were marked differences between axolotls and Xenopus in the expression pattern of these chondrogenesis-associated genes. The relative deficit in the chondrogenic capacity of Xenopus blastema cells may account for the absence of total limb regenerative capacity.

Comparison of tissue processing methods for microvascular visualization in axolotls.

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Montoro, Rodrigo; Dickie, Renee

2017-01-01

The vascular system, the pipeline for oxygen and nutrient delivery to tissues, is essential for vertebrate development, growth, injury repair, and regeneration. With their capacity to regenerate entire appendages throughout their lifespan, axolotls are an unparalleled model for vertebrate regeneration, but they lack many of the molecular tools that facilitate vascular imaging in other animal models. The determination of vascular metrics requires high quality image data for the discrimination of vessels from background tissue. Quantification of the vasculature using perfused, cleared specimens is well-established in mammalian systems, but has not been widely employed in amphibians. The objective of this study was to optimize tissue preparation methods for the visualization of the microvascular network in axolotls, providing a basis for the quantification of regenerative angiogenesis. To accomplish this aim, we performed intracardiac perfusion of pigment-based contrast agents and evaluated aqueous and non-aqueous clearing techniques. The methods were verified by comparing the quality of the vascular images and the observable vascular density across treatment groups. Simple and inexpensive, these tissue processing techniques will be of use in studies assessing vascular growth and remodeling within the context of regeneration. Advantages of this method include: •Higher contrast of the vasculature within the 3D context of the surrounding tissue •Enhanced detection of microvasculature facilitating vascular quantification •Compatibility with other labeling techniques.

Abdominal Distension Associated with Luminal Fungi in the Intestines of Axolotl Larvae

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Chiara Zullian

2015-01-01

Full Text Available Axolotls show a remarkable regeneration capacity compared with higher vertebrates, regenerating missing appendages such as limbs and tail as well as other body parts (i.e., apex of the heart, forebrain, and jaw after amputations which makes this animal a very interesting research model for tissue regeneration mechanisms. Larvae are individually housed in a 20% Holtfreter’s solution within clear plastic containers. The photoperiod light : darkness cycle is 12 : 12 h. Larvae with a total body length of less than 5 cm are fed once a day with large brine shrimp and blood worm. Albino larvae appeared to have a tendency to exhibit abdominal distention. No clinical signs of illness seemed to be associated with the condition; however, these animals exhibit a relatively slower growth rate. To better characterize this condition, we performed histological sectioning for cross sectional slide preparation on wild type and albino axolotl larvae following euthanasia. The only lesion seen in the albino larvae was a thickened gut wall and the presence of fungi within the intestines. We hypothesize that this may be due to a lower efficacy of the albino larvae’s immune system.

Germline Transgenic Methods for Tracking Cells and Testing Gene Function during Regeneration in the Axolotl

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Khattak, Shahryar; Schuez, Maritta; Richter, Tobias; Knapp, Dunja; Haigo, Saori L.; Sandoval-Guzmán, Tatiana; Hradlikova, Kristyna; Duemmler, Annett; Kerney, Ryan; Tanaka, Elly M.

2013-01-01

The salamander is the only tetrapod that regenerates complex body structures throughout life. Deciphering the underlying molecular processes of regeneration is fundamental for regenerative medicine and developmental biology, but the model organism had limited tools for molecular analysis. We describe a comprehensive set of germline transgenic strains in the laboratory-bred salamander Ambystoma mexicanum (axolotl) that open up the cellular and molecular genetic dissection of regeneration. We demonstrate tissue-dependent control of gene expression in nerve, Schwann cells, oligodendrocytes, muscle, epidermis, and cartilage. Furthermore, we demonstrate the use of tamoxifen-induced Cre/loxP-mediated recombination to indelibly mark different cell types. Finally, we inducibly overexpress the cell-cycle inhibitor p16INK4a, which negatively regulates spinal cord regeneration. These tissue-specific germline axolotl lines and tightly inducible Cre drivers and LoxP reporter lines render this classical regeneration model molecularly accessible. PMID:24052945

Live Imaging of Axolotl Digit Regeneration Reveals Spatiotemporal Choreography of Diverse Connective Tissue Progenitor Pools.

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Currie, Joshua D; Kawaguchi, Akane; Traspas, Ricardo Moreno; Schuez, Maritta; Chara, Osvaldo; Tanaka, Elly M

2016-11-21

Connective tissues-skeleton, dermis, pericytes, fascia-are a key cell source for regenerating the patterned skeleton during axolotl appendage regeneration. This complexity has made it difficult to identify the cells that regenerate skeletal tissue. Inability to identify these cells has impeded a mechanistic understanding of blastema formation. By tracing cells during digit tip regeneration using brainbow transgenic axolotls, we show that cells from each connective tissue compartment have distinct spatial and temporal profiles of proliferation, migration, and differentiation. Chondrocytes proliferate but do not migrate into the regenerate. In contrast, pericytes proliferate, then migrate into the blastema and give rise solely to pericytes. Periskeletal cells and fibroblasts contribute the bulk of digit blastema cells and acquire diverse fates according to successive waves of migration that choreograph their proximal-distal and tissue contributions. We further show that platelet-derived growth factor signaling is a potent inducer of fibroblast migration, which is required to form the blastema. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Molecular cloning, sequence analysis and homology modeling of the first caudata amphibian antifreeze-like protein in axolotl (Ambystoma mexicanum).

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Zhang, Songyan; Gao, Jiuxiang; Lu, Yiling; Cai, Shasha; Qiao, Xue; Wang, Yipeng; Yu, Haining

2013-08-01

Antifreeze proteins (AFPs) refer to a class of polypeptides that are produced by certain vertebrates, plants, fungi, and bacteria and which permit their survival in subzero environments. In this study, we report the molecular cloning, sequence analysis and three-dimensional structure of the axolotl antifreeze-like protein (AFLP) by homology modeling of the first caudate amphibian AFLP. We constructed a full-length spleen cDNA library of axolotl (Ambystoma mexicanum). An EST having highest similarity (∼42%) with freeze-responsive liver protein Li16 from Rana sylvatica was identified, and the full-length cDNA was subsequently obtained by RACE-PCR. The axolotl antifreeze-like protein sequence represents an open reading frame for a putative signal peptide and the mature protein composed of 93 amino acids. The calculated molecular mass and the theoretical isoelectric point (pl) of this mature protein were 10128.6 Da and 8.97, respectively. The molecular characterization of this gene and its deduced protein were further performed by detailed bioinformatics analysis. The three-dimensional structure of current AFLP was predicted by homology modeling, and the conserved residues required for functionality were identified. The homology model constructed could be of use for effective drug design. This is the first report of an antifreeze-like protein identified from a caudate amphibian.

On the participation of irradiated tissues in the formation of limb regenerate in axolotls

International Nuclear Information System (INIS)

Tuchkova, S.Ya.

1976-01-01

The aim of the study was to obtain further information on the participation of irradiated tissue cells in formation of regenerated limbs after X-irradiation of axolotls and experimental restoration of the regenerational ability. Cells of irradiated tissues were labeled with H 3 -thymidine; the presence of the label in regenerated tissues would be indicative of participation of irradiated cells in the regeneration process. Irradiation dose was 700 R. 30 axolotls with irradiated limbs were intramuscularly injected with rat muscle homogenate into the right limb once a day beginning from the day of treatment. 15 similarly irradiated animals which did not receive homogenate served as a control. The authors concluded that the presence of highly labeled cells in regenerated tissues was likely to indicate the participation of irradiated tissue cells in regeneration of the limb. However, the quantitative contribution of such cells was impossible to determine since remaining irradiated tissues of the organ contained mostly unlabeled cells. It was also impossible to rule out the possibility of cell migration from non-irradiated tissues [ru

Evidence for an RNA polymerization activity in axolotl and Xenopus egg extracts.

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Hélène Pelczar

2010-12-01

Full Text Available We have previously reported a post-transcriptional RNA amplification observed in vivo following injection of in vitro synthesized transcripts into axolotl oocytes, unfertilized (UFE or fertilized eggs. To further characterize this phenomenon, low speed extracts (LSE from axolotl and Xenopus UFE were prepared and tested in an RNA polymerization assay. The major conclusions are: i the amphibian extracts catalyze the incorporation of radioactive ribonucleotide in RNase but not DNase sensitive products showing that these products correspond to RNA; ii the phenomenon is resistant to α-amanitin, an inhibitor of RNA polymerases II and III and to cordycepin (3'dAMP, but sensitive to cordycepin 5'-triphosphate, an RNA elongation inhibitor, which supports the existence of an RNA polymerase activity different from polymerases II and III; the detection of radiolabelled RNA comigrating at the same length as the exogenous transcript added to the extracts allowed us to show that iii the RNA polymerization is not a 3' end labelling and that iv the radiolabelled RNA is single rather than double stranded. In vitro cell-free systems derived from amphibian UFE therefore validate our previous in vivo results hypothesizing the existence of an evolutionary conserved enzymatic activity with the properties of an RNA dependent RNA polymerase (RdRp.

De novo transcriptome sequencing of axolotl blastema for identification of differentially expressed genes during limb regeneration

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2013-01-01

Background Salamanders are unique among vertebrates in their ability to completely regenerate amputated limbs through the mediation of blastema cells located at the stump ends. This regeneration is nerve-dependent because blastema formation and regeneration does not occur after limb denervation. To obtain the genomic information of blastema tissues, de novo transcriptomes from both blastema tissues and denervated stump ends of Ambystoma mexicanum (axolotls) 14 days post-amputation were sequenced and compared using Solexa DNA sequencing. Results The sequencing done for this study produced 40,688,892 reads that were assembled into 307,345 transcribed sequences. The N50 of transcribed sequence length was 562 bases. A similarity search with known proteins identified 39,200 different genes to be expressed during limb regeneration with a cut-off E-value exceeding 10-5. We annotated assembled sequences by using gene descriptions, gene ontology, and clusters of orthologous group terms. Targeted searches using these annotations showed that the majority of the genes were in the categories of essential metabolic pathways, transcription factors and conserved signaling pathways, and novel candidate genes for regenerative processes. We discovered and confirmed numerous sequences of the candidate genes by using quantitative polymerase chain reaction and in situ hybridization. Conclusion The results of this study demonstrate that de novo transcriptome sequencing allows gene expression analysis in a species lacking genome information and provides the most comprehensive mRNA sequence resources for axolotls. The characterization of the axolotl transcriptome can help elucidate the molecular mechanisms underlying blastema formation during limb regeneration. PMID:23815514

Excretory nitrogen metabolism in the juvenile axolotl Ambystoma mexicanum: differences in aquatic and terrestrial environments.

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Loong, Ai M; Chew, Shit F; Ip, Yuen K

2002-01-01

The fully grown but nonmetamorphosed (juvenile) axolotl Ambystoma mexicanum was ureogenic and primarily ureotelic in water. A complete ornithine-urea cycle (OUC) was present in the liver. Aerial exposure impeded urea (but not ammonia) excretion, leading to a decrease in the percentage of nitrogen excreted as urea in the first 24 h. However, urea and not ammonia accumulated in the muscle, liver, and plasma during aerial exposure. By 48 h, the rate of urea excretion recovered fully, probably due to the greater urea concentration gradient in the kidney. It is generally accepted that an increase in carbamoyl phosphate synthetase activity is especially critical in the developmental transition from ammonotelism to ureotelism in the amphibian. Results from this study indicate that such a transition in A. mexicanum would have occurred before migration to land. Aerial exposure for 72 h exhibited no significant effect on carbamoyl phosphate synthetase-I activity or that of other OUC enzymes (with the exception of ornithine transcarbamoylase) from the liver of the juvenile A. mexicanum. This supports our hypothesis that the capacities of OUC enzymes present in the liver of the aquatic juvenile axolotl were adequate to prepare it for its invasion of the terrestrial environment. The high OUC capacity was further supported by the capability of the juvenile A. mexicanum to survive in 10 mM NH(4)Cl without accumulating amino acids in its body. The majority of the accumulating endogenous and exogenous ammonia was detoxified to urea, which led to a greater than twofold increase in urea levels in the muscle, liver, and plasma and a significant increase in urea excretion by hour 96. Hence, it can be concluded that the juvenile axolotl acquired ureotelism while submerged in water, and its hepatic capacity of urea synthesis was more than adequate to handle the toxicity of endogenous ammonia during migration to land.

Cutaneous mastocytomas in the neotenic caudate amphibians Ambystoma mexicanum (axolotl) and Ambystoma tigrinun (tiger salamander)

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Harshbarger, J.C.; Chang, S.C.; DeLanney, L.E.; Rose, F.L.; Green, D.E.

1999-01-01

Spontaneous mastocytomas studied in 18 axolotls (Ambystoma mexicanum) and six tiger salamanders (Ambystoma tigrinum) were gray-white, uni- to multilobular cutaneous protrusions from 2mm to 2cm in diameter. Tumors were moderately cellular unencapsulated masses that usually infiltrated the dermis and hypodermis with the destruction of intervening tissues. Some tumors were invading superficial bundles of the underlying skeletal muscle. Tumors consisted of mitotically active cells derived from a single lineage but showing a range of differentiation. Immature cells had nearly smooth to lightly cleft or folded basophilic nuclei bordered by a band of cytoplasm with few cytoplasmic processes and containing a few small uniform eccentric granules. Mature cells had basophilic nuclei with deep clefts or folds and abundant eosinophilic cytoplasm with multiple long intertwining cytoplasmic extensions packed with metachromatic granules. The axolotls were old individuals from an inbred laboratory colony. The tiger salamanders were wild animals from a single polluted pond. They could have been old and inbred. Both groups were neotenic. These are the first mastocytomas discovered in cold-blooded animals.

Axolotl hemoglobin: cDNA-derived amino acid sequences of two alpha globins and a beta globin from an adult Ambystoma mexicanum.

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Shishikura, Fumio; Takeuchi, Hiro-aki; Nagai, Takatoshi

2005-11-01

Erythrocytes of the adult axolotl, Ambystoma mexicanum, have multiple hemoglobins. We separated and purified two kinds of hemoglobin, termed major hemoglobin (Hb M) and minor hemoglobin (Hb m), from a five-year-old male by hydrophobic interaction column chromatography on Alkyl Superose. The hemoglobins have two distinct alpha type globin polypeptides (alphaM and alpham) and a common beta globin polypeptide, all of which were purified in FPLC on a reversed-phase column after S-pyridylethylation. The complete amino acid sequences of the three globin chains were determined separately using nucleotide sequencing with the assistance of protein sequencing. The mature globin molecules were composed of 141 amino acid residues for alphaM globin, 143 for alpham globin and 146 for beta globin. Comparing primary structures of the five kinds of axolotl globins, including two previously established alpha type globins from the same species, with other known globins of amphibians and representatives of other vertebrates, we constructed phylogenetic trees for amphibian hemoglobins and tetrapod hemoglobins. The molecular trees indicated that alphaM, alpham, beta and the previously known alpha major globin were adult types of globins and the other known alpha globin was a larval type. The existence of two to four more globins in the axolotl erythrocyte is predicted.

Mexican Perspectives on Mexican-U.S. Relations

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1993-04-01

while serving in the United States military, working in the Bracero program and in American factories. By working with Americans, Mexicans learned that...Mexican government blames the problem on the United States. During the history of the Bracero Program (1942 -1964) 4.6 million Mexicans traveled to...and became familiar to Mexican migrants.ŕ The termination of the Bracero Program did not discourage Mexican agricultural workers from entering the

Axolotl/Bichos Raros Crónica

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Susana Chávez-Silverman

2012-11-01

Full Text Available In this crónica, I pay homage (and talk back to! one of my favourite authors, Julio Cortázar, who I had the great privilege and pleasure of befriending in 1980, when he was a visiting professor at UC-Berkeley. I have been obsessed with time-travel, doubling, and interstitiality since I was very young; even the most casual Cortázar reader (if such a thing is possible will immediately recognise these as recurrent themes in his work. Here, faced with several actual axolotl in a Buenos Aires aquarium, I explore and comment on Cortázar’s strangely mesmerising meditation on identity and transformation. My personal connection is (as in much of my writing concerned with aspects of gender and sexuality suppressed or (more likely ignored in Cortázar’s version. I identify, too, with a poignant in-betweenness and ambiguity I read in the figure of the axolotl—and in the work of Cortázar and Alejandra Pizarnik.

The effects of rotation and positional change of stump tissues upon morphogenesis of the regenerating axolotl limb

NARCIS (Netherlands)

Carlson, Bruce M.

1972-01-01

Rotation of a skin cuff 180° around the proximodistal axis of the upper arm in the axolotl results in the formation of multiple regenerates in about 80° of cases after amputation of the limb through the rotated skin. Rotation of the dermis or the flexor and extensor muscles folowed by amputation

Induction of Metamorphosis Causes Differences in Sex-Specific Allocation Patterns in Axolotls (Ambystoma mexicanum) that Have Different Growth Histories.

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Clarkson, Pamela M; Beachy, Christopher K

2015-12-01

We tested the hypothesis that salamanders growing at different rates would have allocation patterns that differ among male and female metamorphic and larval salamanders. We raised individual axolotls, Ambystoma mexicanum , on four food regimes: constant high growth (throughout the experiment), constant low growth (restricted throughout the experiment), high growth switched to low growth (ad libitum switched after 140 d to restricted), and low growth switched to high growth (restricted switched after 140 d to ad libitum). Because axolotls are obligate paedomorphs, we exposed half of the salamanders to thyroid hormone to induce metamorphosis. We assayed growth and dissected and weighed gonads and fat bodies. Salamanders that were switched from restricted to ad libitum food regime delayed metamorphosis. In all treatment groups, females had larger gonads than males and males had larger fat bodies than females. The association between storage and reproduction differed between larvae and metamorphs and depended on sex.

Functional characterization of the vertebrate primary ureter: Structure and ion transport mechanisms of the pronephric duct in axolotl larvae (Amphibia)

DEFF Research Database (Denmark)

Haugan, Birgitte M; Halberg, Kenneth Agerlin; Jespersen, Åse

2010-01-01

whether the duct is involved in urine modification using larvae of the freshwater amphibian Ambystoma mexicanum (axolotl) as model. Results We investigated structural as well as physiological properties of the pronephric duct. The key elements of our methodology were: using histology, light...

Genic regions of a large salamander genome contain long introns and novel genes

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Bryant Susan V

2009-01-01

Full Text Available Abstract Background The basis of genome size variation remains an outstanding question because DNA sequence data are lacking for organisms with large genomes. Sixteen BAC clones from the Mexican axolotl (Ambystoma mexicanum: c-value = 32 × 109 bp were isolated and sequenced to characterize the structure of genic regions. Results Annotation of genes within BACs showed that axolotl introns are on average 10× longer than orthologous vertebrate introns and they are predicted to contain more functional elements, including miRNAs and snoRNAs. Loci were discovered within BACs for two novel EST transcripts that are differentially expressed during spinal cord regeneration and skin metamorphosis. Unexpectedly, a third novel gene was also discovered while manually annotating BACs. Analysis of human-axolotl protein-coding sequences suggests there are 2% more lineage specific genes in the axolotl genome than the human genome, but the great majority (86% of genes between axolotl and human are predicted to be 1:1 orthologs. Considering that axolotl genes are on average 5× larger than human genes, the genic component of the salamander genome is estimated to be incredibly large, approximately 2.8 gigabases! Conclusion This study shows that a large salamander genome has a correspondingly large genic component, primarily because genes have incredibly long introns. These intronic sequences may harbor novel coding and non-coding sequences that regulate biological processes that are unique to salamanders.

Pathological changes of Golgi complex in hemocytoblasts of spleen of young axolotls after x-irradiation

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Turska, R.

1975-01-01

The data available up to now concerning the structure of Golgi complex in different types of normal and pathologically changed cells are very divergent. Results are reported from detailed studies on changes occurring within the Golgi complex in the spleen of three-month old axolotls after x-ray irradiation with a single dose of 1,200 R and killed by decapitation 15, 30, 60 minutes and 3, 6, and 12 hours after irradiation.

Regulation of Regenerative Responses by Factors in the Extracellular Matrix during Axolotl (Ambystoma mexicanum) Limb Regeneration

OpenAIRE

Phan, Anne Quy

2014-01-01

Salamanders are unique among adult vertebrates in their ability to regenerate complex body structures after traumatic injury. Axolotl limb regeneration is a stepwise sequence of three requisite processes: (1) scarless wound healing to generate a regenerative wound epithelium, (2) blastema formation by migration, proliferation and dedifferentiation to create a mass of multipotent regeneration-competent progenitor cells, and (3) induction of pattern formation by interaction of cells with opposi...

Ultrastructure of the external gill epithelium of the axolotl, Ambystoma mexicanum with reference to ionic transport.

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Jarial, M S; Wilkins, J H

2003-10-01

The ultrastructure of the external gill epithelium of the axolotl, Ambystoma mexicanum, has been examined using conventional transmission electron microscopy to elucidate its role in ionic transport. Four cell types are identified in the gill filament and primary gill bar epithelium. These are granular, ciliated, Leydig and basal cells. A fifth cell type, the flat mitochondria-rich cell is only found in the gill bar epithelium. The predominant granular cells display microvilli at their surface and their cytoplasm contains abundant mitochondria, rough endoplasmic reticulum, Golgi complexes, vesicles and PAS+ secretory granules that are extruded at the surface, which along with secretions from the Leydig cells form a mucous coat. The granular cells are joined apically by junctional complexes consisting of zonulae occludens, zonulae adherens and desmosomes. The lateral membranes of granular cells enclose large intercellular spaces that are closed at the apical ends but remain open at the basal ends adjoining capillaries. In AgNO3-treated axolotl, the gills become darkly stained, the silver grains penetrate apical membranes and appear in the cytoplasm, accumulating near the lateral membranes and also enter the intercellular spaces. These findings are consistent with the dual role of the gill epithelium in mucus production and active ionic transport.

Early regulation of axolotl limb regeneration.

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Makanae, Aki; Satoh, Akira

2012-10-01

Amphibian limb regeneration has been studied for a long time. In amphibian limb regeneration, an undifferentiated blastema is formed around the region damaged by amputation. The induction process of blastema formation has remained largely unknown because it is difficult to study the induction of limb regeneration. The recently developed accessory limb model (ALM) allows the investigation of limb induction and reveals early events of amphibian limb regeneration. The interaction between nerves and wound epidermis/epithelium is an important aspect of limb regeneration. During early limb regeneration, neurotrophic factors act on wound epithelium, leading to development of a functional epidermis/epithelium called the apical epithelial cap (AEC). AEC and nerves create a specific environment that inhibits wound healing and induces regeneration through blastema formation. It is suggested that FGF-signaling and MMP activities participate in creating a regenerative environment. To understand why urodele amphibians can create such a regenerative environment and humans cannot, it is necessary to identify the similarities and differences between regenerative and nonregenerative animals. Here we focus on ALM to consider limb regeneration from a new perspective and we also reported that focal adhesion kinase (FAK)-Src signaling controlled fibroblasts migration in axolotl limb regeneration. Copyright © 2012 Wiley Periodicals, Inc.

Explanatory Emotion Talk in Mexican Immigrant and Mexican American Families.

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Cervantes, Christi A.

2002-01-01

Mother-child conversations during story-telling play were analyzed for patterns of emotion talk. Subjects were 48 Mexican immigrant and Mexican American mothers and their children aged 3-4. Contrary to previous findings, Mexican immigrant mothers used more explanations of emotions than labels. Mexican American mothers used both, equally. Results…

An assessment of individual-level factors associated with alcohol treatment utilization among Mexican Americans.

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Reingle Gonzalez, Jennifer M; Caetano, Raul; Mills, Britain A; Vaeth, Patrice A C

2014-01-01

The purpose of this study is to identify enabling factors for treatment utilization for alcohol-related problems, and to evaluate how enabling factors vary by need for treatment, among two samples of Mexican American adults. These two distinct samples included 2,595 current and former drinkers (one sample included 787 U.S./Mexico border residents; the other sample included 740 Mexican Americans living in U.S. cities not proximal to the border). Need for treatment (alcohol disorder severity) and (male) gender were the primary correlates of treatment utilization; and there was no moderation in the enabling factors by need for treatment as "enablers" of utilization. Further theoretical and empirical research is necessary to determine which mechanisms are driving disparities in treatment utilization across racial/ethnic groups generally, and Hispanic national groups specifically. Copyright © 2014 Elsevier Inc. All rights reserved.

[Specific growth rate and the rate of energy metabolism in the ontogenesis of axolotl, Ambystoma mexicanum (Amphibia: Ambystomatidae)].

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Vladimirova, I G; Kleĭmenov, S Iu; Alekseeva, T A; Radzinskaia, L I

2003-01-01

Concordant changes in the rate of energy metabolism and specific growth rate of axolotls have been revealed. Several periods of ontogeny are distinguished, which differ in the ratio of energy metabolism to body weight and, therefore, are described by different allometric equations. It is suggested that the specific growth rate of an animal determines the type of dependence of energy metabolism on body weight.

Absence of mutation at the 5'-upstream promoter region of the TPM4 gene from cardiac mutant axolotl (Ambystoma mexicanum).

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Denz, Christopher R; Zhang, Chi; Jia, Pingping; Du, Jianfeng; Huang, Xupei; Dube, Syamalima; Thomas, Anish; Poiesz, Bernard J; Dube, Dipak K

2011-09-01

Tropomyosins are a family of actin-binding proteins that show cell-specific diversity by a combination of multiple genes and alternative RNA splicing. Of the 4 different tropomyosin genes, TPM4 plays a pivotal role in myofibrillogenesis as well as cardiac contractility in amphibians. In this study, we amplified and sequenced the upstream regulatory region of the TPM4 gene from both normal and mutant axolotl hearts. To identify the cis-elements that are essential for the expression of the TPM4, we created various deletion mutants of the TPM4 promoter DNA, inserted the deleted segments into PGL3 vector, and performed promoter-reporter assay using luciferase as the reporter gene. Comparison of sequences of the promoter region of the TPM4 gene from normal and mutant axolotl revealed no mutations in the promoter sequence of the mutant TPM4 gene. CArG box elements that are generally involved in controlling the expression of several other muscle-specific gene promoters were not found in the upstream regulatory region of the TPM4 gene. In deletion experiments, loss of activity of the reporter gene was noted upon deletion which was then restored upon further deletion suggesting the presence of both positive and negative cis-elements in the upstream regulatory region of the TPM4 gene. We believe that this is the first axolotl promoter that has ever been cloned and studied with clear evidence that it functions in mammalian cell lines. Although striated muscle-specific cis-acting elements are absent from the promoter region of TPM4 gene, our results suggest the presence of positive and negative cis-elements in the promoter region, which in conjunction with positive and negative trans-elements may be involved in regulating the expression of TPM4 gene in a tissue-specific manner.

Lineage tracing of genome-edited alleles reveals high fidelity axolotl limb regeneration.

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Flowers, Grant Parker; Sanor, Lucas D; Crews, Craig M

2017-09-16

Salamanders are unparalleled among tetrapods in their ability to regenerate many structures, including entire limbs, and the study of this ability may provide insights into human regenerative therapies. The complex structure of the limb poses challenges to the investigation of the cellular and molecular basis of its regeneration. Using CRISPR/Cas, we genetically labelled unique cell lineages within the developing axolotl embryo and tracked the frequency of each lineage within amputated and fully regenerated limbs. This allowed us, for the first time, to assess the contributions of multiple low frequency cell lineages to the regenerating limb at once. Our comparisons reveal that regenerated limbs are high fidelity replicas of the originals even after repeated amputations.

The axolotl limb blastema: cellular and molecular mechanisms driving blastema formation and limb regeneration in tetrapods

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McCusker, Catherine; Bryant, Susan V.

2015-01-01

Abstract The axolotl is one of the few tetrapods that are capable of regenerating complicated biological structures, such as complete limbs, throughout adulthood. Upon injury the axolotl generates a population of regeneration‐competent limb progenitor cells known as the blastema, which will grow, establish pattern, and differentiate into the missing limb structures. In this review we focus on the crucial early events that occur during wound healing, the neural−epithelial interactions that drive the formation of the early blastema, and how these mechanisms differ from those of other species that have restricted regenerative potential, such as humans. We also discuss how the presence of cells from the different axes of the limb is required for the continued growth and establishment of pattern in the blastema as described in the polar coordinate model, and how this positional information is reprogrammed in blastema cells during regeneration. Multiple cell types from the mature limb stump contribute to the blastema at different stages of regeneration, and we discuss the contribution of these types to the regenerate with reference to whether they are “pattern‐forming” or “pattern‐following” cells. Lastly, we explain how an engineering approach will help resolve unanswered questions in limb regeneration, with the goal of translating these concepts to developing better human regenerative therapies. PMID:27499868

Metamorfosis: La animalidad y el mito en La Metamorfosis de Kafka y Axolotl de Cortázar

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Catalina Villalobos Díaz

2017-07-01

Full Text Available El presente artículo propone una lectura de la animalidad, principalmente de la metamorfosis, por medio de dos relatos de dos grandes escritores de la literatura: Axolotl, de Julio Cortázar, y La Metamorfosis, de Franz Kafka. A través de estos textos, se plantea un análisis con respecto a lo que representa una transformación y el mito tras la metamorfosis como tal.

Dual embryonic origin and patterning of the pharyngeal skeleton in the axolotl (Ambystoma mexicanum).

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Sefton, Elizabeth M; Piekarski, Nadine; Hanken, James

2015-01-01

The impressive morphological diversification of vertebrates was achieved in part by innovation and modification of the pharyngeal skeleton. Extensive fate mapping in amniote models has revealed a primarily cranial neural crest derivation of the pharyngeal skeleton. Although comparable fate maps of amphibians produced over several decades have failed to document a neural crest derivation of ventromedial elements in these vertebrates, a recent report provides evidence of a mesodermal origin of one of these elements, basibranchial 2, in the axolotl. We used a transgenic labeling protocol and grafts of labeled cells between GFP+ and white embryos to derive a fate map that describes contributions of both cranial neural crest and mesoderm to the axolotl pharyngeal skeleton, and we conducted additional experiments that probe the mechanisms that underlie mesodermal patterning. Our fate map confirms a dual embryonic origin of the pharyngeal skeleton in urodeles, including derivation of basibranchial 2 from mesoderm closely associated with the second heart field. Additionally, heterotopic transplantation experiments reveal lineage restriction of mesodermal cells that contribute to pharyngeal cartilage. The mesoderm-derived component of the pharyngeal skeleton appears to be particularly sensitive to retinoic acid (RA): administration of exogenous RA leads to loss of the second basibranchial, but not the first. Neural crest was undoubtedly critical in the evolution of the vertebrate pharyngeal skeleton, but mesoderm may have played a central role in forming ventromedial elements, in particular. When and how many times during vertebrate phylogeny a mesodermal contribution to the pharyngeal skeleton evolved remain to be resolved. © 2015 Wiley Periodicals, Inc.

Collection of gametes from live axolotl, Ambystoma mexicanum, and standardization of in vitro fertilization.

Science.gov (United States)

Mansour, N; Lahnsteiner, F; Patzner, R A

2011-01-15

This study established the first protocol for collection of gametes from live axolotl, Ambystoma mexicanum, by gentle abdominal massage and in vitro fertilization. To stimulate spermiation and ovulation, human chorionic gonadotrophin (hCG) and Ovopel pellets, which are commercially used to stimulate spawning in fish, were tested. The hCG was more effective than Ovopel pellets and yielded a higher semen volume in the injected males and a shorter response time in the females. Collected semen by this method was already motile and fertile. Fertile eggs could be collected in 3-4 successive collection times after the female has started the typical spawning behaviour. The fertilization condition that yielded the highest hatching rate was mixing semen with eggs before the addition of a fertilization saline solution (20 mmol/l NaCl, 1 mmol/l KCl, 1 mmol/l Mg(2)SO(4), 1 mmol Ca(2)Cl, 3 mmol NaHCO(3), 10 mmol/l Tris, pH 8.5 - Osmolality = 65 mosmol/kg). When the pH of the fertilization solution was increased to ≥ 10, the hatching rate was significantly increased. The use of fertilization solutions with osmolalities of ≥ 150 and ≥ 182 were accompanied with a significant decrease in hatching rates and the appearance of deformed larvae, respectively. In conclusion, a reliable protocol for gamete collection from live axolotl is established as a laboratory model of in vitro fertilization for urodele amphibians. This protocol may be transferable to endangered urodeles. Copyright © 2011 Elsevier Inc. All rights reserved.

Proliferation zones in the axolotl brain and regeneration of the telencephalon

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Maden Malcolm

2013-01-01

Full Text Available Abstract Background Although the brains of lower vertebrates are known to exhibit somewhat limited regeneration after incisional or stab wounds, the Urodele brain exhibits extensive regeneration after massive tissue removal. Discovering whether and how neural progenitor cells that reside in the ventricular zones of Urodeles proliferate to mediate tissue repair in response to injury may produce novel leads for regenerative strategies. Here we show that endogenous neural progenitor cells resident to the ventricular zone of Urodeles spontaneously proliferate, producing progeny that migrate throughout the telencephalon before terminally differentiating into neurons. These progenitor cells appear to be responsible for telencephalon regeneration after tissue removal and their activity may be up-regulated by injury through an olfactory cue. Results There is extensive proliferation of endogenous neural progenitor cells throughout the ventricular zone of the adult axolotl brain. The highest levels are observed in the telencephalon, especially the dorsolateral aspect, and cerebellum. Lower levels are observed in the mesencephalon and rhombencephalon. New cells produced in the ventricular zone migrate laterally, dorsally and ventrally into the surrounding neuronal layer. After migrating from the ventricular zone, the new cells primarily express markers of neuronal differentiative fates. Large-scale telencephalic tissue removal stimulates progenitor cell proliferation in the ventricular zone of the damaged region, followed by proliferation in the tissue that surrounds the healing edges of the wound until the telencephalon has completed regeneration. The proliferative stimulus appears to reside in the olfactory system, because telencephalic regeneration does not occur in the brains of olfactory bulbectomized animals in which the damaged neural tissue simply heals over. Conclusion There is a continual generation of neuronal cells from neural progenitor cells

What's Values Got to Do with It? Thriving among Mexican/Mexican American College Students

Science.gov (United States)

Morgan Consoli, Melissa L.; Llamas, Jasmín; Consoli, Andrés J.

2016-01-01

The authors examined traditional Mexican/Mexican American and perceived U.S. mainstream cultural values as predictors of thriving. One hundred twenty-four (37 men, 87 women) self-identified Mexican/Mexican American college students participated in the study. The traditional Mexican/Mexican American cultural values of family support and religion…

Role of thyroid hormones in the normal and glucocorticosteroid hormone-induced evolution of carbamoyl-phosphate synthase (ammonia) activity in axolotl liver

NARCIS (Netherlands)

Lamers, W. H.; Vink, C.; Charles, R.

1978-01-01

1. In axolotl liver, the activity of carbamoyl-phosphate synthase (ammonia), expressed per mg liver protein, decreases to a minimum at 5 months of age, then increases to a maximum at 8 months of age which is followed by a decrease again. The initial decrease between 3 and 5 months of age appears to

The Axolotl Fibula as a Model for the Induction of Regeneration across Large Segment Defects in Long Bones of the Extremities

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Chen, Xiaoping; Song, Fengyu; Jhamb, Deepali; Li, Jiliang; Bottino, Marco C.; Palakal, Mathew J.; Stocum, David L.

2015-01-01

We tested the ability of the axolotl (Ambystoma mexicanum) fibula to regenerate across segment defects of different size in the absence of intervention or after implant of a unique 8-braid pig small intestine submucosa (SIS) scaffold, with or without incorporated growth factor combinations or tissue protein extract. Fractures and defects of 10% and 20% of the total limb length regenerated well without any intervention, but 40% and 50% defects failed to regenerate after either simple removal of bone or implanting SIS scaffold alone. By contrast, scaffold soaked in the growth factor combination BMP-4/HGF or in protein extract of intact limb tissue promoted partial or extensive induction of cartilage and bone across 50% segment defects in 30%-33% of cases. These results show that BMP-4/HGF and intact tissue protein extract can promote the events required to induce cartilage and bone formation across a segment defect larger than critical size and that the long bones of axolotl limbs are an inexpensive model to screen soluble factors and natural and synthetic scaffolds for their efficacy in stimulating this process. PMID:26098852

The Axolotl Fibula as a Model for the Induction of Regeneration across Large Segment Defects in Long Bones of the Extremities.

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Xiaoping Chen

Full Text Available We tested the ability of the axolotl (Ambystoma mexicanum fibula to regenerate across segment defects of different size in the absence of intervention or after implant of a unique 8-braid pig small intestine submucosa (SIS scaffold, with or without incorporated growth factor combinations or tissue protein extract. Fractures and defects of 10% and 20% of the total limb length regenerated well without any intervention, but 40% and 50% defects failed to regenerate after either simple removal of bone or implanting SIS scaffold alone. By contrast, scaffold soaked in the growth factor combination BMP-4/HGF or in protein extract of intact limb tissue promoted partial or extensive induction of cartilage and bone across 50% segment defects in 30%-33% of cases. These results show that BMP-4/HGF and intact tissue protein extract can promote the events required to induce cartilage and bone formation across a segment defect larger than critical size and that the long bones of axolotl limbs are an inexpensive model to screen soluble factors and natural and synthetic scaffolds for their efficacy in stimulating this process.

CRISPR-Mediated Genomic Deletion of Sox2 in the Axolotl Shows a Requirement in Spinal Cord Neural Stem Cell Amplification during Tail Regeneration

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Ji-Feng Fei

2014-09-01

Full Text Available The salamander is the only tetrapod that functionally regenerates all cell types of the limb and spinal cord (SC and thus represents an important regeneration model, but the lack of gene-knockout technology has limited molecular analysis. We compared transcriptional activator-like effector nucleases (TALENs and clustered regularly interspaced short palindromic repeats (CRISPRs in the knockout of three loci in the axolotl and find that CRISPRs show highly penetrant knockout with less toxic effects compared to TALENs. Deletion of Sox2 in up to 100% of cells yielded viable F0 larvae with normal SC organization and ependymoglial cell marker expression such as GFAP and ZO-1. However, upon tail amputation, neural stem cell proliferation was inhibited, resulting in spinal-cord-specific regeneration failure. In contrast, the mesodermal blastema formed normally. Sox3 expression during development, but not regeneration, most likely allowed embryonic survival and the regeneration-specific phenotype. This analysis represents the first tissue-specific regeneration phenotype from the genomic deletion of a gene in the axolotl.

An Aryl Hydrocarbon Receptor from the Salamander Ambystoma mexicanum Exhibits Low Sensitivity to 2,3,7,8-Tetrachlorodibenzo-p-dioxin.

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Shoots, Jenny; Fraccalvieri, Domenico; Franks, Diana G; Denison, Michael S; Hahn, Mark E; Bonati, Laura; Powell, Wade H

2015-06-02

Structural features of the aryl hydrocarbon receptor (AHR) can underlie species- and population-specific differences in its affinity for 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). These differences often explain variations in TCDD toxicity. Frogs are relatively insensitive to dioxin, and Xenopus AHRs bind TCDD with low affinity. Weak TCDD binding results from the combination of three residues in the ligand-binding domain: A354 and A370, and N325. Here we sought to determine whether this mechanism of weak TCDD binding is shared by other amphibian AHRs. We isolated an AHR cDNA from the Mexican axolotl (Ambystoma mexicanum). The encoded polypeptide contains identical residues at positions that confer low TCDD affinity to X. laevis AHRs (A364, A380, and N335), and homology modeling predicts they protrude into the binding cavity. Axolotl AHR bound one-tenth the TCDD of mouse AHR in velocity sedimentation analysis, and in transactivation assays, the EC50 for TCDD was 23 nM, similar to X. laevis AHR1β (27 nM) and greater than AHR containing the mouse ligand-binding domain (0.08 nM). Sequence, modeled structure, and function indicate that axolotl AHR binds TCDD weakly, predicting that A. mexicanum lacks sensitivity toTCDD toxicity. We hypothesize that this characteristic of axolotl and Xenopus AHRs arose in a common ancestor of the Caudata and Anura.

Fine structure of the epidermal Leydig cells in the axolotl Ambystoma mexicanum in relation to their function.

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Jarial, M S

1989-01-01

The fine structure of the Leydig cells in the epidermis of the strictly aquatic adult axolotl Ambystoma mexicanum resembles that of similar cells in larval salamanders. The major finding of this study is that the mucous secretion of the Leydig cells is released into the intercellular spaces from which it is discharged through pores onto the surface of the epidermis where it forms a mucous layer to protect the skin. Images Figs. 1-2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Figs. 11-13 PMID:2630544

Microarray analysis of a salamander hopeful monster reveals transcriptional signatures of paedomorphic brain development

Science.gov (United States)

2010-01-01

Background The Mexican axolotl (Ambystoma mexicanum) is considered a hopeful monster because it exhibits an adaptive and derived mode of development - paedomorphosis - that has evolved rapidly and independently among tiger salamanders. Unlike related tiger salamanders that undergo metamorphosis, axolotls retain larval morphological traits into adulthood and thus present an adult body plan that differs dramatically from the ancestral (metamorphic) form. The basis of paedomorphic development was investigated by comparing temporal patterns of gene transcription between axolotl and tiger salamander larvae (Ambystoma tigrinum tigrinum) that typically undergo a metamorphosis. Results Transcript abundances from whole brain and pituitary were estimated via microarray analysis on four different days post hatching (42, 56, 70, 84 dph) and regression modeling was used to independently identify genes that were differentially expressed as a function of time in both species. Collectively, more differentially expressed genes (DEGs) were identified as unique to the axolotl (n = 76) and tiger salamander (n = 292) than were identified as shared (n = 108). All but two of the shared DEGs exhibited the same temporal pattern of expression and the unique genes tended to show greater changes later in the larval period when tiger salamander larvae were undergoing anatomical metamorphosis. A second, complementary analysis that directly compared the expression of 1320 genes between the species identified 409 genes that differed as a function of species or the interaction between time and species. Of these 409 DEGs, 84% exhibited higher abundances in tiger salamander larvae at all sampling times. Conclusions Many of the unique tiger salamander transcriptional responses are probably associated with metamorphic biological processes. However, the axolotl also showed unique patterns of transcription early in development. In particular, the axolotl showed a genome-wide reduction in mRNA abundance

Microarray analysis of a salamander hopeful monster reveals transcriptional signatures of paedomorphic brain development

Directory of Open Access Journals (Sweden)

Putta Srikrishna

2010-06-01

Full Text Available Abstract Background The Mexican axolotl (Ambystoma mexicanum is considered a hopeful monster because it exhibits an adaptive and derived mode of development - paedomorphosis - that has evolved rapidly and independently among tiger salamanders. Unlike related tiger salamanders that undergo metamorphosis, axolotls retain larval morphological traits into adulthood and thus present an adult body plan that differs dramatically from the ancestral (metamorphic form. The basis of paedomorphic development was investigated by comparing temporal patterns of gene transcription between axolotl and tiger salamander larvae (Ambystoma tigrinum tigrinum that typically undergo a metamorphosis. Results Transcript abundances from whole brain and pituitary were estimated via microarray analysis on four different days post hatching (42, 56, 70, 84 dph and regression modeling was used to independently identify genes that were differentially expressed as a function of time in both species. Collectively, more differentially expressed genes (DEGs were identified as unique to the axolotl (n = 76 and tiger salamander (n = 292 than were identified as shared (n = 108. All but two of the shared DEGs exhibited the same temporal pattern of expression and the unique genes tended to show greater changes later in the larval period when tiger salamander larvae were undergoing anatomical metamorphosis. A second, complementary analysis that directly compared the expression of 1320 genes between the species identified 409 genes that differed as a function of species or the interaction between time and species. Of these 409 DEGs, 84% exhibited higher abundances in tiger salamander larvae at all sampling times. Conclusions Many of the unique tiger salamander transcriptional responses are probably associated with metamorphic biological processes. However, the axolotl also showed unique patterns of transcription early in development. In particular, the axolotl showed a genome

Enablers and inhibitors of the implementation of the Casalud Model, a Mexican innovative healthcare model for non-communicable disease prevention and control.

Science.gov (United States)

Tapia-Conyer, Roberto; Saucedo-Martinez, Rodrigo; Mujica-Rosales, Ricardo; Gallardo-Rincon, Hector; Campos-Rivera, Paola Abril; Lee, Evan; Waugh, Craig; Guajardo, Lucia; Torres-Beltran, Braulio; Quijano-Gonzalez, Ursula; Soni-Gallardo, Lidia

2016-07-22

The Mexican healthcare system is under increasing strain due to the rising prevalence of non-communicable diseases (especially type 2 diabetes), mounting costs, and a reactive curative approach focused on treating existing diseases and their complications rather than preventing them. Casalud is a comprehensive primary healthcare model that enables proactive prevention and disease management throughout the continuum of care, using innovative technologies and a patient-centred approach. Data were collected over a 2-year period in eight primary health clinics (PHCs) in two states in central Mexico to identify and assess enablers and inhibitors of the implementation process of Casalud. We used mixed quantitative and qualitative data collection tools: surveys, in-depth interviews, and participant and non-participant observations. Transcripts and field notes were analyzed and coded using Framework Analysis, focusing on defining and describing enablers and inhibitors of the implementation process. We identified seven recurring topics in the analyzed textual data. Four topics were categorized as enablers: political support for the Casalud model, alignment with current healthcare trends, ongoing technical improvements (to ease adoption and support), and capacity building. Three topics were categorized as inhibitors: administrative practices, health clinic human resources, and the lack of a shared vision of the model. Enablers are located at PHCs and across all levels of government, and include political support for, and the technological validity of, the model. The main inhibitor is the persistence of obsolete administrative practices at both state and PHC levels, which puts the administrative feasibility of the model's implementation in jeopardy. Constructing a shared vision around the model could facilitate the implementation of Casalud as well as circumvent administrative inhibitors. In order to overcome PHC-level barriers, it is crucial to have an efficient and

Mexican Parenting Questionnaire (MPQ)

Science.gov (United States)

Halgunseth, Linda C.; Ispa, Jean M.

2012-01-01

The present study was conducted in four phases and constructed a self-report parenting instrument for use with Mexican immigrant mothers of children aged 6 to 10. The 14-item measure was based on semistructured qualitative interviews with Mexican immigrant mothers (N = 10), was refined by a focus group of Mexican immigrant mothers (N = 5), and was…

Mexican Society of Bioelectromagnetism

International Nuclear Information System (INIS)

Canedo, Luis

2008-01-01

In July 2007 physicians, biologists and physicists that have collaborated in previous meetings of the medical branch of the Mexican Physical Society constituted the Mexican Society of Bioelectromagnetism with the purpose of promote scientific study of the interaction of electromagnetic energy (at frequencies ranging from zero Hertz through those of visible light) and acoustic energy with biological systems. A second goal was to increase the contribution of medical and biological professionals in the meetings of the medical branch of the Mexican Physical Society. The following paragraphs summarize some objectives of the Mexican Society of Bioelectromagnetism for the next two years

Positional information in axolotl and mouse limb extracellular matrix is mediated via heparan sulfate and fibroblast growth factor during limb regeneration in the axolotl (Ambystoma mexicanum).

Science.gov (United States)

Phan, Anne Q; Lee, Jangwoo; Oei, Michelle; Flath, Craig; Hwe, Caitlyn; Mariano, Rachele; Vu, Tiffany; Shu, Cynthia; Dinh, Andrew; Simkin, Jennifer; Muneoka, Ken; Bryant, Susan V; Gardiner, David M

2015-08-01

Urodele amphibians are unique among adult vertebrates in their ability to regenerate complex body structures after traumatic injury. In salamander regeneration, the cells maintain a memory of their original position and use this positional information to recreate the missing pattern. We used an in vivo gain-of-function assay to determine whether components of the extracellular matrix (ECM) have positional information required to induce formation of new limb pattern during regeneration. We discovered that salamander limb ECM has a position-specific ability to either inhibit regeneration or induce de novo limb structure, and that this difference is dependent on heparan sulfates that are associated with differential expression of heparan sulfate sulfotransferases. We also discovered that an artificial ECM containing only heparan sulfate was sufficient to induce de novo limb pattern in salamander limb regeneration. Finally, ECM from mouse limbs is capable of inducing limb pattern in axolotl blastemas in a position-specific, developmental-stage-specific, and heparan sulfate-dependent manner. This study demonstrates a mechanism for positional information in regeneration and establishes a crucial functional link between salamander regeneration and mammals.

Corticotropin-releasing hormone-mediated metamorphosis in the neotenic axolotl Ambystoma mexicanum: synergistic involvement of thyroxine and corticoids on brain type II deiodinase.

Science.gov (United States)

Kühn, Eduard R; De Groef, Bert; Van der Geyten, Serge; Darras, Veerle M

2005-08-01

In the present study, morphological changes leading to complete metamorphosis have been induced in the neotenic axolotl Ambystoma mexicanum using a submetamorphic dose of T(4) together with an injection of corticotropin-releasing hormone (CRH). An injection of CRH alone is ineffective in this regard presumably due to a lack of thyrotropic stimulation. Using this low hormone profile for induction of metamorphosis, the deiodinating enzymes D2 and D3 known to be present in amphibians were measured in liver and brain 24h following an intraperitoneal injection. An injection of T(4) alone did not influence liver nor brain D2 and D3, but dexamethasone (DEX) or CRH alone or in combination with T(4) decreased liver D2 and D3. Brain D2 activity was slightly increased with a higher dose of DEX, though CRH did not have this effect. A profound synergistic effect occurred when T(4) and DEX or CRH were injected together, in the dose range leading to metamorphosis, increasing brain D2 activity more than fivefold. This synergistic effect was not found in the liver. It is concluded that brain T(3) availability may play an important role for the onset of metamorphosis in the neotenic axolotl.

Foreign firms to get equal opportunity in Mexican selloff plans

International Nuclear Information System (INIS)

Wood, A.; Alvarez, C.

1993-01-01

Petroleos Mexicanos (Pemex) has not finalized details of its long-awaited petrochemical privatization program. However, the state oil group has made it clear the selloff schedule, due to begin during the next two months, will give equal investment opportunity to foreign firms, dashing the hopes of Mexican groups that they would be given first right of refusal in the privatization program. Meanwhile, Pemex has agreed with Shell Oil on a previously announced refining joint venture involving Shell's 225,000-bbl/day refinery at Deer Park, TX. Under the plan, Pemex will purchase a 50% stake in the refinery and join Shell in a $1-billion upgrade with would enable it to handle more Mexican crude. Sources believe that Shell and other US oil groups are interested in acquiring assets from Pemex Petroquimica

Trajectories of Mexican American and mainstream cultural values among Mexican American adolescents.

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Knight, George P; Basilio, Camille D; Cham, Heining; Gonzales, Nancy A; Liu, Yu; Umaña-Taylor, Adriana J

2014-12-01

Mexican Americans are one of the largest and fastest growing ethnic groups in the United States, yet we have limited knowledge regarding changes (i.e., developmental trajectories) in cultural orientation based upon their exposure to the Mexican American and mainstream cultures. We examined the parallel trajectories of Mexican American and mainstream cultural values in a sample of 749 Mexican American adolescents (49 % female) across assessments during the fifth grade (approximately 11 years of age), the seventh grade (approximately 13 years of age) and the tenth grade (approximately 16 years of age). We expected that these values would change over this developmental period and this longitudinal approach is more appropriate than the often used median split classification to identify distinct types of acculturation. We found four distinct acculturation trajectory groups: two trajectory groups that were increasing slightly with age in the endorsement of mainstream cultural values, one of which was relatively stable in Mexican American cultural values while the other was declining in their endorsement of these values; and two trajectory groups that were declining substantially with age in their endorsement of mainstream cultural values, one of which was also declining in Mexican American cultural values and the other which was stable in these values. These four trajectory groups differed in expected ways on a number of theoretically related cultural variables, but were not highly consistent with the median split classifications. The findings highlight the need to utilize longitudinal data to examine the developmental changes of Mexican American individual's adaptation to the ethnic and mainstream culture in order to understand more fully the processes of acculturation and enculturation.

The yeast two hybrid system in a screen for proteins interacting with axolotl (Ambystoma mexicanum) Msx1 during early limb regeneration.

Science.gov (United States)

Abuqarn, Mehtap; Allmeling, Christina; Amshoff, Inga; Menger, Bjoern; Nasser, Inas; Vogt, Peter M; Reimers, Kerstin

2011-07-01

Urodele amphibians are exceptional in their ability to regenerate complex body structures such as limbs. Limb regeneration depends on a process called dedifferentiation. Under an inductive wound epidermis terminally differentiated cells transform to pluripotent progenitor cells that coordinately proliferate and eventually redifferentiate to form the new appendage. Recent studies have developed molecular models integrating a set of genes that might have important functions in the control of regenerative cellular plasticity. Among them is Msx1, which induced dedifferentiation in mammalian myotubes in vitro. Herein, we screened for interaction partners of axolotl Msx1 using a yeast two hybrid system. A two hybrid cDNA library of 5-day-old wound epidermis and underlying tissue containing more than 2×10⁶ cDNAs was constructed and used in the screen. 34 resulting cDNA clones were isolated and sequenced. We then compared sequences of the isolated clones to annotated EST contigs of the Salamander EST database (BLASTn) to identify presumptive orthologs. We subsequently searched all no-hit clone sequences against non redundant NCBI sequence databases using BLASTx. It is the first time, that the yeast two hybrid system was adapted to the axolotl animal model and successfully used in a screen for proteins interacting with Msx1 in the context of amphibian limb regeneration. 2011 Elsevier B.V. All rights reserved.

Fair Start Program: Outreach to Mexican and Mexican American Farmworker Families.

Science.gov (United States)

Winters-Smith, Carol; Larner, Mary

This presentation describes a home visiting health education program serving Mexican and Mexican-American migrant farmworkers in Florida. The purposes of the program were to educate farmworker families about pregnancy, childbirth, nutrition, and child development, and to encourage the use of preventive health care services. Home visitors were…

Cartilage and bone cells do not participate in skeletal regeneration in Ambystoma mexicanum limbs.

Science.gov (United States)

McCusker, Catherine D; Diaz-Castillo, Carlos; Sosnik, Julian; Q Phan, Anne; Gardiner, David M

2016-08-01

The Mexican Axolotl is one of the few tetrapod species that is capable of regenerating complete skeletal elements in injured adult limbs. Whether the skeleton (bone and cartilage) plays a role in the patterning and contribution to the skeletal regenerate is currently unresolved. We tested the induction of pattern formation, the effect on cell proliferation, and contributions of skeletal tissues (cartilage, bone, and periosteum) to the regenerating axolotl limb. We found that bone tissue grafts from transgenic donors expressing GFP fail to induce pattern formation and do not contribute to the newly regenerated skeleton. Periosteum tissue grafts, on the other hand, have both of these activities. These observations reveal that skeletal tissue does not contribute to the regeneration of skeletal elements; rather, these structures are patterned by and derived from cells of non-skeletal connective tissue origin. Copyright © 2016 Elsevier Inc. All rights reserved.

Higher risk for obesity among Mexican-American and Mexican immigrant children and adolescents than among peers in Mexico.

Science.gov (United States)

Hernández-Valero, María A; Bustamante-Montes, L Patricia; Hernández, Mike; Halley-Castillo, Elizabeth; Wilkinson, Anna V; Bondy, Melissa L; Olvera, Norma

2012-08-01

We conducted a cross-sectional study among 1,717 children and adolescents of Mexican origin ages 5-19 years living in Mexico and Texas to explore the influence of country of birth and country of longest residence on their overweight and obesity status. Descriptive statistics were used to compare demographic and anthropometric characteristics of participants born and raised in Mexico (Mexicans), born in Mexico and raised in the United States (Mexican immigrants), and born and raised in the United States (Mexican-Americans). Univariate and multivariate nominal logistic regression was used to determine the demographic predictors of obesity adjusted by country of birth, country of residence, age, and gender. Almost half (48.8%) of the Mexican-Americans and 43.2% of the Mexican immigrants had body mass index at the 85th percentile or above, compared to only 29.3% of the Mexicans (P obese than their Mexican peers [Mexican-Americans: odds ratio (OR) = 2.5 (95% confidence interval [CI] 1.8-3.4); Mexican immigrants: OR = 2.2 (95% CI 1.6-3.0)]. In addition, males were more likely than females to be obese [OR = 1.6 (95% CI 1.2-2.1)], and adolescents 15-19 years of age were less likely than their younger counterparts [OR = 0.5 (95% CI 0.4-0.7)] to be obese. The high prevalence of obesity among children of Mexican origin in the United States is of great concern and underscores the urgent need to develop and implement obesity preventive interventions targeting younger children of Mexican origin, especially newly arrived immigrant children. In addition, future obesity research should take into consideration the country of origin of the study population to develop more culturally specific obesity interventions.

The Mexican American.

Science.gov (United States)

Rowan, Helen

The purpose of this paper, prepared for the U. S. Commission on Civil Rights, is to indicate the types and ranges of problems facing the Mexican American community and to suggest ways in which these problems are peculiar to Mexican Americans. Specific examples are cited to illustrate major problems and personal experiences. Topics covered in the…

Mexican Revolution

OpenAIRE

Scheuzger, Stephan

2016-01-01

It was the complex and far-reaching transformation of the Mexican Revolution rather than the First World War that left its mark on Mexican history in the second decade of the 20th century. Nevertheless, although the country maintained its neutrality in the international conflict, it was a hidden theatre of war. Between 1914 and 1918, state actors in Germany, Great Britain and the United States defined their policies towards Mexico and its nationalist revolution with a view not only to improve...

Leucine-enkephalin-like immunoreactivity is localized in luteinizing hormone-producing cells in the axolotl (Ambystoma mexicanum) pituitary.

Science.gov (United States)

Suzuki, Hirohumi; Yamamoto, Toshiharu

2014-02-01

In this study, we used immunohistochemical techniques to determine the cell type of leucine-enkephalin (Leu-ENK)-immunoreactive cells in the axolotl (Ambystoma mexicanum) pituitary. Immunoreactive cells were scattered throughout the pars distalis except for the dorso-caudal portion. These cells were immuno-positive for luteinizing hormone (LH), but they were immuno-negative for adrenocorticotrophic, growth, and thyroid-stimulating hormones, as well as prolactin. Immunoelectron microscopy demonstrated that Leu-ENK-like substance and LH co-localized within the same secretory granules. Leu-ENK secreted from gonadotrophs may participate in LH secretion in an autocrine fashion, and/or may participate in the release of sex steroids together with LH. Copyright © 2013 Elsevier Ltd. All rights reserved.

Subjective Social Status, Mental and Psychosocial Health, and Birth Weight Differences in Mexican-American and Mexican Immigrant Women.

Science.gov (United States)

Fleuriet, K Jill; Sunil, T S

2015-12-01

Recent Mexican immigrant women on average have an unexpectedly low incidence of low birth weight (LBW). Birth weights decline and LBW incidence increases in post-immigrant generations. This pilot project tested the hypothesis that subjective social status (SSS) of pregnant women predicts variation in birth weight between Mexican immigrant and Mexican-American women. 300 low-income pregnant Mexican immigrant and Mexican-American women in South Texas were surveyed for SSS, depression, pregnancy-related anxiety, perceived social stress and self-esteem and subsequent birth weight. No significant difference in SSS levels between pregnant Mexican immigrant and Mexican-American women were found. However, SSS better predicted variation in birth weight across both groups than mental and psychosocial health variables. Results suggest distinct relationships among SSS, mental and psychosocial health that could impact birth weight. They underscore the relevance of a multilevel, biopsychosocial analytical framework to studying LBW.

Severe necrotizing myocarditis caused by serratia marcescens infection in an axolotl (Ambystoma mexicanum).

Science.gov (United States)

Del-Pozo, J; Girling, S; Pizzi, R; Mancinelli, E; Else, R W

2011-05-01

This report provides the first account of the pathological changes associated with infection by Serratia marcescens in an adult male axolotl. The infection resulted in septicaemia with severe multifocal necrotizing myocarditis. The latter lesion evolved to cardiac rupture, haemopericardium and death resulting from cardiac tamponade. This animal was exposed to higher than usual temperatures (24-25 °C) 2 weeks before the onset of disease and this may have resulted in immunocompromise and opportunistic bacterial infection. S. marcescens was isolated from the coelomic and pericardial cavity. Both isolates were identical and were resistant to β-lactam antibiotics, but not to aminoglycosides or fluoroquinolones. The production of red prodigiosin pigment by the bacterium suggested an environmental origin. Overall, the clinical and histopathological presentation suggests that S. marcescens should be included in the list of aetiological agents of the 'red-leg'/bacterial dermatosepticaemia syndrome of amphibians. Copyright © 2010 Elsevier Ltd. All rights reserved.

The Mexican oil industry

International Nuclear Information System (INIS)

Marcos-Giacoman, E.

1991-01-01

In the environment of growing domestic demand and enhanced international competitiveness, Petroleos Mexicanos (PEMEX)-the Mexican national oil company-faces the challenge of not only responding adequately to the rapid changes taking place in the Mexican economy, but making a significant contribution towards solid and stable growth. This paper reports that the relevant concern is how PEMEX is going to live up to these expectations. The Mexican oil industry, especially including the petrochemical sector, has great potential in terms of an ample domestic market as well as external foreign-currency-generating markets

Forecasting the electricity consumption of the Mexican border states maquiladoras

Energy Technology Data Exchange (ETDEWEB)

Flores, C.E.; Phelan, P.E. [Arizona State Univ., Dept. of Mechanical and Aerospace Engineering, Tempe, AZ (United States); Mou, J.-I. [Taiwan Semiconductor Manufacturing Co., Operation Planning Div., Hsin-Chu (Taiwan); Bryan, H. [Arizona State Univ., School of Architecture, Tempe, AZ (United States)

2004-07-01

The consumption of electricity by maquiladora industries in the Mexican border states is an important driver for determining future powerplant needs in that area. An industrial electricity forecasting model is developed for the border states' maquiladoras, and the outputs are compared with a reference forecasting model developed for the US industrial sector, for which considerably more data are available. This model enables the prediction of the effect of implementing various energy efficiency measures in the industrial sector. As an illustration, here the impact of implementing energy-efficient lighting and motors in the Mexican border states' maquiladoras was determined to be substantial. Without such energy efficiency measures, electricity consumption for these industries is predicted to rise by 64% from 2001 to 2010, but if these measures are implemented on a gradual basis over the same time period, electricity consumption is forecast to rise by only 36%. (Author)

[Influence of predisposing, enabling, and health care need variables on the use of dental health services among Mexican adolescents from a semi-rural location].

Science.gov (United States)

Pontigo-Loyola, América Patricia; Medina-Solís, Carlo Eduardo; Márquez-Corona, María de Lourdes; Vallejos-Sánchez, Ana Alicia; Minaya-Sánchez, Mirna; Escoffié-Ramírez, Mauricio; Maupomé, Gerardo

2012-01-01

The purpose of this study was to quantify the influence of some of the predisposing, enabling, and healthcare need variables on dental health services utilization (DHSU) among Mexican adolescents. This is a cross-sectional analytical study including 1,538 Mexican teenagers 12 and 15 years of age. The dependent variable was DHSU in the previous 12 months. Data were collected through a questionnaire and included demographic, socioeconomic, and behavioral factors. The study included an oral examination. The analysis included nonparametric statistics and a logistic regression model. Of the 1,538 adolescents, 688 were 12 years old and 850 were 15 years old. Girls accounted for 49.9%. The prevalence of DHSU was 15%. In the final model we found that having moved at least once from the community in which the child was born was associated with DHSU (OR: 1.24; 95% CI: 1.10-1.40; p > 0.05), just as it was observed for purchasing purified water for home consumption instead of relying on piped water supplies (OR: 1.52; 95% CI: 1.03-2.25), higher educational attainment of the mother (OR: 1.39; 95% CI: 1.02-1.91) and of the father (OR: 1.87; 95% CI: 1.09-3.19). Having more sound teeth (OR: 0.96; 95% CI: 0.94-0.98), and having at least one tooth with caries (OR: 1.10; 95% CI: 1.01-1.18) were also associated with DHSU (p > 0.05). The percentage of subjects with DHSU in the prior 12 months was low compared with other studies. Our identification of the variables associated with DHSU (often surrogates of socioeconomic position) indicated the existence of oral health inequalities and the need to develop strategies to reduce the gaps identified.

The relationship between Mexican American cultural values and resilience among Mexican American college students: a mixed methods study.

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Morgan Consoli, Melissa L; Llamas, Jasmin D

2013-10-01

The current study investigated the role of cultural values in the resilience of Mexican American college students. Utilizing mixed methodology, 124 self-identified Mexican American college students were asked to complete an online survey, including a demographic questionnaire, the Resilience Scale, Mexican American Cultural Values Scale, and 2 open-ended questions concerning overcoming adversity and cultural values. As hypothesized, Mexican American traditional cultural values (Familismo, Respeto, Religiosidad, and Traditional Gender Roles) predicted resilience, with Familismo accounting for the majority of the variance. Consensual qualitative research (Hill, Thompson, & Nutt Williams, 1997) was used to identify emergent domains and themes within the open-ended question responses. Traditional Mexican American Value themes included Familismo, Ethnic Identity, Religiosidad, Perseverance, and Respeto. Results highlight the important role that certain Mexican American cultural values play in providing strength for overcoming adversities.

Perceived social stress, pregnancy-related anxiety, depression and subjective social status among pregnant Mexican and Mexican American women in south Texas.

Science.gov (United States)

Fleuriet, K Jill; Sunil, T S

2014-05-01

The purpose of this study was to determine differences in subjective social status, perceived social stress, depressive symptoms, and pregnancy-related anxiety between pregnant Mexican American and Mexican immigrant women. Three hundred pregnant Mexican immigrant and Mexican American women in South Texas were surveyed for pregnancy-related anxiety, perceived social stress, depressive symptoms, and subjective social status. Pregnant Mexican immigrant women had higher levels of pregnancy-related anxiety and lower levels of depression and perceived social stress than pregnant Mexican American women. Change in these variables among Mexican immigrant women was relatively linear as time of residence in the United States increased. Mexican immigrant and Mexican American women had significantly different correlations between subjective social status, self-esteem and perceived social stress. Results indicate that subjective social status is an important psychosocial variable among pregnant Hispanic women. Results contribute to ongoing efforts to provide culturally responsive prenatal psychosocial support services.

Another Mexican birthweight paradox? The role of residential enclaves and neighborhood poverty in the birthweight of Mexican-origin infants.

Science.gov (United States)

Osypuk, Theresa L; Bates, Lisa M; Acevedo-Garcia, Dolores

2010-02-01

Examining whether contextual factors influence the birth outcomes of Mexican-origin infants in the US may contribute to assessing rival explanations for the so-called Mexican health paradox. We examined whether birthweight among infants born to Mexican-origin women in the US was associated with Mexican residential enclaves and exposure to neighborhood poverty, and whether these associations were modified by nativity (i.e. mother's place of birth). We calculated metropolitan indices of neighborhood exposure to Mexican-origin population and poverty for the Mexican-origin population, and merged with individual-level, year 2000 natality data (n=490,332). We distinguished between neighborhood exposure to US-born Mexican-origin population (i.e. ethnic enclaves) and neighborhood exposure to foreign-born (i.e. Mexico-born) Mexican-origin population (i.e. immigrant enclaves). We used 2-level hierarchical linear regression models adjusting for individual, metropolitan, and regional covariates and stratified by nativity. We found that living in metropolitan areas with high residential segregation of US-born Mexican-origin residents (i.e. high prevalence of ethnic enclaves) was associated with lower birthweight for infants of US-born Mexican-origin mothers before and after covariate adjustment. When simultaneously adjusting for exposure to ethnic and immigrant enclaves, the latter became positively associated with birthweight and the negative effect of the former increased, among US-born mothers. We found no contextual birthweight associations for mothers born in Mexico in adjusted models. Our findings highlight a differential effect of context by nativity, and the potential health effects of ethnic enclaves, which are possibly a marker of downward assimilation, among US-born Mexican-origin women. Copyright 2009 Elsevier Ltd. All rights reserved.

A cross-over in Mexican and Mexican-American fertility rates: Evidence and explanations for an emerging paradox

Directory of Open Access Journals (Sweden)

Patrick Heuveline

2005-03-01

Full Text Available Against a backdrop of two new developments in the fertility behavior of the Mexican- Origin population in the U.S., the present discussion will update contemporary Mexican-Origin fertility patterns and address several theoretical weaknesses in the current approach to minority group fertility. Data come from six national surveys (three from Mexico and three from the U.S. that cover a twenty-five year period (1975-2000. The findings demonstrate dramatic decreases in the fertility rates in Mexico at the same time that continuous increases have been documented in the fertility rates of third-or-later generation Mexican-Americans in the U.S., particularly at younger ages. These changes necessitate a reexamination of the ubiquitous theory that Mexican pronatalist values are responsible for the high fertility rates found within the Mexican-Origin population in the U.S. Instead, they point to the increasing relevance of framing the fertility behavior of the Mexican-Origin population within a racial stratification perspective that stresses the influence of U.S. social context on fertility behavior. As a step in this direction, the analysis examines fertility patterns within the Mexican-Origin population in the U.S. Special attention is given to the role of nativity/generational status in contributing to within group differences.

Obesity and central adiposity in Mexican adults: results from the Mexican National Health and Nutrition Survey 2006.

Science.gov (United States)

Barquera, Simón; Campos-Nonato, Ismael; Hernández-Barrera, Lucía; Flores, Mario; Durazo-Arvizu, Ramón; Kanter, Rebecca; Rivera, Juan A

2009-01-01

To estimate the prevalence of overweight, obesity and central adiposity in Mexico, and to explore trends compared to the previous Mexican National Health Survey (ENSA 2000) and to Mexican-Americans. The Mexican National Health and Nutrition Survey 2006 (ENSANUT 2006) was used to describe overweight, obesity and central adiposity. Trends over time were assessed using the ENSA 2000 and by comparing the ENSANUT 2006 results to those of Mexican-Americans using the United States National Health and Nutrition Examination Survey (NHANES) 1999-2000 and 2005-2006. A total of 33023 adults > 20 years old were included; 39.7% were found to be overweight and 29.9% were found to be obese; 75.9% of all adults had abdominal obesity. In Mexico between 2000 and 2006, the combined prevalence of overweight and obesity in adults increased approximately 12%. Mexican-Americans showed a higher prevalence of morbid obesity compared to native Mexicans. Mexico has experienced a rapid increase in the number of adults who have experienced excess weight gain between the years 2000 and 2006.

Localization of amylin-like immunoreactivity in melanocyte-stimulating hormone-containing cells of the pars intermedia but not those of the pars distalis in the axolotl (Ambystoma mexicanum) pituitary.

Science.gov (United States)

Suzuki, Hirohumi; Yamamoto, Toshiharu

2016-04-01

Immunohistochemical techniques were employed to investigate the distribution of amylin-like immunoreactivity in the axolotl (Ambystoma mexicanum) pituitary. Amylin-immunoreactive cells were observed in the pars intermedia, and these cells were found to be immunoreactive for α-melanocyte-stimulating hormone (αMSH) as well. In contrast, αMSH-immunoreactive cells in the pars distalis were immuno-negaitive for amylin. These light microscopic findings were confirmed by immunoelectron microscopy. Amylin-immunoreactive signals were located on the haloes of presumable secretory granules in association with αMSH-immunoreactive signals in the amylin-positive cells. However, in the pars distalis, the αMSH-positive cells did not contain amylin-immunoreactive secretory granules. Western blot analysis of axolotl pituitary extracts revealed the labeling of a protein band at approximately 10.5-kDa by the anti-rat amylin serum, which was not labeled by the anti-αMSH antibody. These findings indicate that amylin secreted from MSH-producing cells in the pars intermedia may modulate MSH secretion in an autocrine fashion and may participate in MSH functions such as fatty homeostasis together with MSH. Copyright © 2016 Elsevier GmbH. All rights reserved.

Microarray and cDNA sequence analysis of transcription during nerve-dependent limb regeneration

Directory of Open Access Journals (Sweden)

Bryant Susan V

2009-01-01

Full Text Available Abstract Background Microarray analysis and 454 cDNA sequencing were used to investigate a centuries-old problem in regenerative biology: the basis of nerve-dependent limb regeneration in salamanders. Innervated (NR and denervated (DL forelimbs of Mexican axolotls were amputated and transcripts were sampled after 0, 5, and 14 days of regeneration. Results Considerable similarity was observed between NR and DL transcriptional programs at 5 and 14 days post amputation (dpa. Genes with extracellular functions that are critical to wound healing were upregulated while muscle-specific genes were downregulated. Thus, many processes that are regulated during early limb regeneration do not depend upon nerve-derived factors. The majority of the transcriptional differences between NR and DL limbs were correlated with blastema formation; cell numbers increased in NR limbs after 5 dpa and this yielded distinct transcriptional signatures of cell proliferation in NR limbs at 14 dpa. These transcriptional signatures were not observed in DL limbs. Instead, gene expression changes within DL limbs suggest more diverse and protracted wound-healing responses. 454 cDNA sequencing complemented the microarray analysis by providing deeper sampling of transcriptional programs and associated biological processes. Assembly of new 454 cDNA sequences with existing expressed sequence tag (EST contigs from the Ambystoma EST database more than doubled (3935 to 9411 the number of non-redundant human-A. mexicanum orthologous sequences. Conclusion Many new candidate gene sequences were discovered for the first time and these will greatly enable future studies of wound healing, epigenetics, genome stability, and nerve-dependent blastema formation and outgrowth using the axolotl model.

Precise control of miR-125b levels is required to create a regeneration-permissive environment after spinal cord injury: a cross-species comparison between salamander and rat

Directory of Open Access Journals (Sweden)

Juan Felipe Diaz Quiroz

2014-06-01

Full Text Available Most spinal cord injuries lead to permanent paralysis in mammals. By contrast, the remarkable regenerative abilities of salamanders enable full functional recovery even from complete spinal cord transections. The molecular differences underlying this evolutionary divergence between mammals and amphibians are poorly understood. We focused on upstream regulators of gene expression as primary entry points into this question. We identified a group of microRNAs (miRNAs that are conserved between the Mexican axolotl salamander (Ambystoma mexicanum and mammals but show marked cross-species differences in regulation patterns following spinal cord injury. We found that precise post-injury levels of one of these miRNAs (miR-125b is essential for functional recovery, and guides correct regeneration of axons through the lesion site in a process involving the direct downstream target Sema4D in axolotls. Translating these results to a mammalian model, we increased miR-125b levels in the rat through mimic treatments following spinal cord transection. These treatments downregulated Sema4D and other glial-scar-related genes, and enhanced the animal’s functional recovery. Our study identifies a key regulatory molecule conserved between salamander and mammal, and shows that the expression of miR-125b and Sema4D must be carefully controlled in the right cells at the correct level to promote regeneration. We also show that these molecular components of the salamander’s regeneration-permissive environment can be experimentally harnessed to improve treatment outcomes for mammalian spinal cord injuries.

Racial Identity and Racial Treatment of Mexican Americans.

Science.gov (United States)

Ortiz, Vilma; Telles, Edward

2012-04-01

How racial barriers play in the experiences of Mexican Americans has been hotly debated. Some consider Mexican Americans similar to European Americans of a century ago that arrived in the United States with modest backgrounds but were eventually able to participate fully in society. In contrast, others argue that Mexican Americans have been racialized throughout U.S. history and this limits their participation in society. The evidence of persistent educational disadvantages across generations and frequent reports of discrimination and stereotyping support the racialization argument. In this paper, we explore the ways in which race plays a role in the lives of Mexican Americans by examining how education, racial characteristics, social interactions, relate to racial outcomes. We use the Mexican American Study Project, a unique data set based on a 1965 survey of Mexican Americans in Los Angeles and San Antonio combined with surveys of the same respondents and their adult children in 2000, thereby creating a longitudinal and intergenerational data set. First, we found that darker Mexican Americans, therefore appearing more stereotypically Mexican, report more experiences of discrimination. Second, darker men report much more discrimination than lighter men and than women overall. Third, more educated Mexican Americans experience more stereotyping and discrimination than their less-educated counterparts, which is partly due to their greater contact with Whites. Lastly, having greater contact with Whites leads to experiencing more stereotyping and discrimination. Our results are indicative of the ways in which Mexican Americans are racialized in the United States.

Green Medicine: Traditional Mexican-American Herbal Remedies.

Science.gov (United States)

Torres, Eliseo

Traditional Mexican American herbal potions and remedies and their history are explained in an introductory book for the general reader. The importance of curanderismo, or green medicine, in Mexican and Mexican American cultures is explored. A brief history traces the herbal aspects of curanderismo through Mayan and Aztec cultures, the Spanish…

Alcohol Use Disorders in National Samples of Mexicans and Mexican-Americans: The Mexican National Addiction Survey and the U.S. National Alcohol Survey

Science.gov (United States)

Borges, Guilherme; Medina-Mora, Maria Elena; Lown, Anne; Ye, Yu; Robertson, Marjorie J.; Cherpitel, Cheryl; Greenfield, Tom

2006-01-01

The authors show associations between immigration and alcohol disorders using data from the 1995 and 2000 U.S. National Alcohol Surveys and the 1998 Mexico National Household Survey on Addictions. The prevalence of alcohol dependence was 4.8% for the Mexicans, 4.2% for the Mexico-born immigrants, and 6.6% for the U.S.-born Mexican Americans. They…

Idioms of Distress Among Depressed White-Non-Mexican and Mexican-Origin Older Men.

Science.gov (United States)

Apesoa-Varano, Ester Carolina; Barker, Judith C; Unutzer, Jurgen; Aguilar-Gaxiola, Sergio; Johnson, Megan Dwight; Tran, Cindy; Guarnaccia, Peter; Hinton, Ladson

2015-09-01

Older men are less likely than older women to receive depression treatment. Latino older men in particular have been found to have significantly lower rates of depression treatment than their white-non-Mexican (WNM) counterparts. Prior research has shown that men are less likely than women to express overt affect and/or report depression symptoms that may prompt primary care physicians' inquiry about depression. Previous studies have overlooked the idioms of distress common among older men. This study investigates: a) the range of idioms of distress that emerge in the narratives of depressed older men, and b) the use of these idioms among depressed WNM and Mexican-origin older men. The present report is based on qualitative data collected through the Men's Health and Aging Study (MeHAS), a mixed-method study of clinically depressed WNM and Mexican-origin older (65 and above) men recruited in primary care settings. Qualitative analysis of 77 interviews led to identification of idioms of distress and informed idiom categories. Study findings show that: a) both groups of men utilized a range of idioms of distress that met current DSM criteria for depression, b) both groups were also likely to utilize idioms that feel outside clinical depression criteria, and c) there were similarities as well as differences between WNM and Mexican-origin men. This study provides a larger vocabulary that clinicians might consider in recognizing depression and initiating depression care for older men from diverse ethnic backgrounds. This is important to improve depression care among older men in general and those of Mexican-origin in particular.

El Arte Culinario Mexicano (Mexican Culinary Art).

Science.gov (United States)

Card, Michelle

This unit in Mexican cooking can be used in Junior High School home economics classes to introduce students to Mexican culture or as a mini-course in Spanish at almost any level. It is divided into two parts. Part One provides historical background and information on basic foods, the Mexican market, shopping tips, regional cooking and customs.…

Reproductive habitus, psychosocial health, and birth weight variation in Mexican immigrant and Mexican American women in south Texas.

Science.gov (United States)

Fleuriet, K Jill; Sunil, T S

2015-08-01

The Latina Paradox, or persistent, unexplained variation in low birth weight rates in recently immigrated Mexican women and the trend toward higher rates in subsequent generations of Mexican American women, is most often attributed to unidentified sociocultural causes. We suggest herein that different disciplinary approaches can be synthesized under the constructs of reproductive habitus and subjective social status to identify influences of sociocultural processes on birth weight. Reproductive habitus are "modes of living the reproductive body, bodily practices, and the creation of new subjects through interactions between people and structures" (Smith-Oka, 2012: 2276). Subjective social status infers comparison of self to others based on community definitions of status or socioeconomic status (Adler 2007). We present results from a prospective study of low-income Mexican immigrant and Mexican American women from south Texas that tested the ability of reproductive habitus and subjective social status to elucidate the Latina Paradox. We hypothesized that reproductive habitus between Mexican immigrant women and Mexican American women inform different subjective social statuses during pregnancy, and different subjective social statuses mediate responses to psychosocial stressors known to correlate with low birth weight. Six hundred thirty-one women were surveyed for psychosocial health, subjective social status, and reproductive histories between 2011 and 2013. Eighty-three women were interviewed between 2012 and 2013 for status during pregnancy, prenatal care practices, and pregnancy narratives and associations. Birth weight was extracted from medical records. Results were mixed. Subjective social status and pregnancy-related anxiety predicted low birth weight in Mexican immigrant but not Mexican American women. Mexican immigrant women had significantly lower subjective social status scores but a distinct reproductive habitus that could explain improved psychosocial

Two Decades of Mexican Particle Physics at Fermilab

International Nuclear Information System (INIS)

Rubinstein, R.

2003-01-01

This report is a view from Fermilab of Mexican particle physics at the Laboratory since about 1980; it is not intended to be a history of Mexican particle physics: that topic is outside the expertise of the writer. The period 1980 to the present coincides with the growth of Mexican experimental particle physics from essentially no activity to its current state where Mexican groups take part in experiments at several of the world's major laboratories

National Mexican Tourism Policy and North American Second Homeowners In Mexico: Local Tourism Development and Mexican Identity (Chapter 6)

DEFF Research Database (Denmark)

Clausen, Helene Balslev

2018-01-01

. Still the Mexican state does not seize the second home owners as a resource and ‘producers’ rather only as consumers of different Mexican objects, food etc. The chapter addresses this research gap and proposes rather than only perceive North American second home owners as part of tourism development...... participate in reshaping and reconfigure public policy and Mexican culture/identity construction. The purpose of the chapter is to explore the role of the North American second home owners and their impact on the planning and regulation of Mexican state policies, and how they might reconfigure practices and...

Engineering assessment of inactive uranium mill tailings: Mexican Hat Site, Mexican Hat, Utah

International Nuclear Information System (INIS)

1981-09-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Mexican Hat site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Mexican Hat, Utah. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 2.2 million tons of tailings at the Mexican Hat site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material to removal of the tailings to remote disposal sites and decontamination of the tailings site. Cost estimates for the four options range from about $15,200,000 for stabilization in place, to about $45,500,000 for disposal at a distance of about 16 mi. Three principal alternatives for the reprocessing of the Mexican Hat tailings were examined: heap leaching; treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $115/lb of U 3 O 8 whether by heap leach or conventional plant processes. The spot market price for uranium was $25/lb early in 1981. Reprocessing the Mexican Hat tailings for uranium recovery is not economically attractive under present conditions

Weight status of Mexican immigrant women: a comparison with women in Mexico and with US-born Mexican American women.

Science.gov (United States)

Guendelman, Sylvia D; Ritterman-Weintraub, Miranda L; Fernald, Lia C H; Kaufer-Horwitz, Martha

2013-09-01

We assessed the association between birthplace, residence, or years in the United States and actual weight (body mass index), perceived weight accuracy, or provider screens for overweight or obesity among Mexican immigrant women. We used linked data from Health and Nutrition Examination Survey waves 2001-2006 and 2006 National Mexican Health and Nutrition Survey to compare 513 immigrants with 9527 women in Mexico and 342 US-born Mexican American women. Immigrants were more likely than women in Mexico to be obese and to perceive themselves as overweight or obese after adjustment for confounders. Recent immigrants had similar weight-related outcomes as women in Mexico. Immigrants were less likely to be obese than were US-born Mexican Americans. Within the overweight or obese population, reported provider screens were higher among immigrants than among women in Mexico, but lower than among US-born Mexican Americans. US residency of at least 5 years but less than 20 years and reporting insufficient provider screens elevated obesity risk. Mexican-origin women in the United States and Mexico are at risk for overweight and obesity. We found no evidence of a "healthy immigrant" effect.

Craniofacial Secular Change in Recent Mexican Migrants.

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Spradley, Katherine; Stull, Kyra E; Hefner, Joseph T

2016-01-01

Research by economists suggests that recent Mexican migrants are better educated and have higher socioeconomic status (SES) than previous migrants. Because factors associated with higher SES and improved education can lead to positive secular changes in overall body form, secular changes in the craniofacial complex were analyzed within a recent migrant group from Mexico. The Mexican group represents individuals in the act of migration, not yet influenced by the American environment, and thus can serve as a starting point for future studies of secular change in this population group. The excavation of a historic Hispanic cemetery in Tucson, Arizona, also allows for a comparison between historic Hispanics and recent migrants to explore craniofacial trends over a broad time period, as both groups originate from Mexico. The present research addresses two main questions: (1) Are cranial secular changes evident in recent Mexican migrants? (2) Are historic Hispanics and recent Mexican migrants similar? By studying secular changes within a migrant population group, secular trends may be detected, which will be important for understanding the biological variation of the migrants themselves and will serve as a preliminary investigation of secular change within Mexican migrants. The comparison of a sample of recent Mexican migrants with a historic Hispanic sample, predominantly of Mexican origin, allows us to explore morphological similarities and differences between early and recent Mexicans within the United States. Vault and face size and a total of 82 craniofacial interlandmark distances were used to explore secular changes within the recent Mexican migrants (females, n = 38; males, n = 178) and to explore the morphological similarities between historic Hispanics (females, n = 54; males, n = 58) and recent migrants. Sexes were separated, and multivariate adaptive regression splines and basis splines (quadratic with one knot) were used to assess the direction and magnitude

Los Dos Mundos: Rural Mexican Americans, Another America.

Science.gov (United States)

Baker, Richard

This book explores race relations between Mexican Americans and Anglo Americans in "Middlewest," a fictitious name for an actual rural Idaho community with the highest proportion of Mexican Americans in the state. Many Mexican Americans in this predominantly agricultural area are current or former migrant workers. The first chapter…

Mexican Marine Corps in the Struggle for Scalable Security and Its Potential as a Guarantor of the Mexican Safety

Science.gov (United States)

2013-03-20

53 G. Elena. Presidente Peña pide a militares a participar en la transformación de México. 1...security of the government of Mexico and the Mexican people until the civilian police is able to do so. 1S. SUBJECT TERMS MAGTF Concept;Mexican...to contribute better to the safety and security of the government of Mexico and the Mexican people until the civilian police is able to do so

Patterns of contraceptive use among Mexican-origin women

Directory of Open Access Journals (Sweden)

Kari White

2013-06-01

Full Text Available BACKGROUND Mexican women in the United States (US have higher rates of fertility compared to other ethnic groups and women in Mexico. Whether variation in women's access to family planning services or patterns of contraceptive use contributes to this higher fertility has received little attention. OBJECTIVE We explore Mexican women's contraceptive use, taking into account women's place in the reproductive life course. METHODS Using nationally representative samples from the US (National Survey of Family Growth and Mexico (Encuesta National de la Dinámica Demográfica, we compared the parity-specific frequency of contraceptive use and fertility intentions for non-migrant women, foreign-born Mexicans in the US, US-born Mexicans, and whites. RESULTS Mexican women in the US were less likely to use IUDs and more likely to use hormonal contraception than women in Mexico. Female sterilization was the most common method among higher parity women in both the US and Mexico, however, foreign-born Mexicans were less likely to be sterilized, and the least likely to use any permanent contraceptive method. Although foreign-born Mexicans were slightly less likely to report that they did not want more children, differences in method use remained after controlling for women's fertility intentions. CONCLUSIONS At all parities, foreign-born Mexicans used less effective methods. These findings suggest that varying access to family planning services may contribute to variation in women's contraceptive use. COMMENTS Future studies are needed to clarify the extent to which disparities in fertility result from differences in contraceptive access.

Mexican Women, Migration and Sex Roles.

Science.gov (United States)

Baca, Reynaldo; Dexter, Bryan

1985-01-01

Compares Mexican women involved in migration to understand how their sex roles and status have been affected. Uses data from two separate studies: ethnography on migrants' wives left at home in a Mexican village and a survey of unauthorized immigrants in the Los Angeles area. (SA)

Engineering assessment of inactive uranium mill tailings: Mexican Hat site, Mexican Hat, Utah. Summary

International Nuclear Information System (INIS)

1981-09-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Mexican Hat site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Mexican Hat, Utah. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 2.2 million tons of tailings at the Mexican Hat site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material to removal of the tailings to remote disposal sites and decontamination of the tailings site. Cost estimates for the four options range from about $15,200,000 for stabilization in place, to about $45,500,000 for disposal at a distance of about 16 mi. Three principal alternatives for the reprocessing of the Mexican Hat tailings were examined: (a) heap leaching; treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $115/lb of U 3 O 8 whether by heap leach or conventional plant processes. The spot market price for uranium was $25/lb early in 1981. Reprocessing the Mexican Hat tailings for uranium recovery is not economically attractive under present conditions

Oxygen consumption and cytochrome exidase activity of axolotl limbs muscle tissue in restoration of regenerative ability suprressed by X-irradiation

International Nuclear Information System (INIS)

Teplits, N.A.

1975-01-01

The rate of oxygen use and activity of cytochrome oxidase in a homogenate of mitochondria and nuclei of muscle tissue of axolotl limbs after suppression of their regenerative capability by x irradiation and their restoration was studied experimentally. With suppression of the regenative capability the use of oxygen was depressed. Cytochrome oxidase activity in the homogenate and mitochondria decreased compared to that of the intact limb, in the nuclei of muscle tissue it was the same or greater. With restoration of the regenerative capability of the limbs the respiration rate of the homogenate and the mitochondria increased, accompanied by increased cytochrome oxidase activity. In the nuclei the cytochrome oxidase activity did not change in the blastema stage and sharply decreased in the limb formation state. (E.T.)

Oxygen consumption and cytochrome exidase activity of axolotl limbs muscle tissue in restoration of regenerative ability suppressed by X-irradiation

Energy Technology Data Exchange (ETDEWEB)

Teplits, N A [AN SSSR, Moscow. Inst. Biologii Razvitiya

1975-01-01

The rate of oxygen use and activity of cytochrome oxidase in a homogenate of mitochondria and nuclei of muscle tissue of axolotl limbs after suppression of their regenerative capability by x irradiation and their restoration was studied experimentally. With suppression of the regenative capability the use of oxygen was depressed. Cytochrome oxidase activity in the homogenate and mitochondria decreased compared to that of the intact limb, in the nuclei of muscle tissue it was the same or greater. With restoration of the regenerative capability of the limbs the respiration rate of the homogenate and the mitochondria increased, accompanied by increased cytochrome oxidase activity. In the nuclei the cytochrome oxidase activity did not change in the blastema stage and sharply decreased in the limb formation state.

The Mexican Committee against Racism and What It Reveals about Relations between Mexican and American Jews

Directory of Open Access Journals (Sweden)

Ariela Katz Gugenheim

2012-10-01

Full Text Available This work reconstructs the origin, organization, development, and disappearance of the Mexican Committee against Racism (Comité Mexicano contra el Racismo, CMR, active in Mexico City from 1944 to 1946, inthe context of the relations between a leading Jewish organization in the United States and a Mexican Jewish institution. The CMR appears in historiography as a Mexican anti-fascist institution, but this research reveals that it was conceived, implemented, financed, and supervised by the American Jewish Committee (AJC, a Jewish social action organization based in the United States, with the aim of fighting against racist and anti-Semitic prejudices, creating a friendly climate towards Jewish-refugee immigration, and quelling anti-American feelings in Mexico. The AJC's involvement was kept a secret for Mexicans in general and for the Jewish community in Mexico. Drawing on archives in Mexico and the United States, this work details the reasons that led to its organization, describes its implementation, explains why the AJC's involvement was kept a secret, and why the CMR failed to prosper and eventually disappeared.

Parental Factors Associated with Mexican American Adolescent Alcohol Use

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Cristina Mogro-Wilson

2013-01-01

Full Text Available The purpose of this study is to further the understanding of how parenting and the relationship between the parent and the youth influence adolescent alcohol use in Mexican American families, with particular attention to acculturation. Results indicated that parental warmth is a strong factor in predicting adolescent alcohol use among Mexican adolescents. The parent-youth relationship played an important role in lowering alcohol use for Mexican American youth. Acculturation has an impact on the level of warmth, control, and the parent-youth relationship for Mexican American families. Findings indicate that there are unique family mechanisms for Mexican American families that should be considered when developing prevention and treatment options.

Ex vivo generation of a functional and regenerative wound epithelium from axolotl (Ambystoma mexicanum) skin.

Science.gov (United States)

Ferris, Donald R; Satoh, Akira; Mandefro, Berhan; Cummings, Gillian M; Gardiner, David M; Rugg, Elizabeth L

2010-10-01

Urodele amphibians (salamanders) are unique among adult vertebrates in their ability to regenerate structurally complete and fully functional limbs. Regeneration is a stepwise process that requires interactions between keratinocytes, nerves and fibroblasts. The formation of a wound epithelium covering the amputation site is an early and necessary event in the process but the molecular mechanisms that underlie the role of the wound epithelium in regeneration remain unclear. We have developed an ex vivo model that recapitulates many features of in vivo wound healing. The model comprises a circular explant of axolotl (Ambystoma mexicanum) limb skin with a central circular, full thickness wound. Re-epithelialization of the wound area is rapid (typically <11 h) and is dependent on metalloproteinase activity. The ex vivo wound epithelium is viable, responds to neuronal signals and is able to participate in ectopic blastema formation and limb regeneration. This ex vivo model provides a reproducible and tractable system in which to study the cellular and molecular events that underlie wound healing and regeneration. © 2010 The Authors. Journal compilation © 2010 Japanese Society of Developmental Biologists.

Comparative transcriptional profiling of the axolotl limb identifies a tripartite regeneration-specific gene program.

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Dunja Knapp

Full Text Available Understanding how the limb blastema is established after the initial wound healing response is an important aspect of regeneration research. Here we performed parallel expression profile time courses of healing lateral wounds versus amputated limbs in axolotl. This comparison between wound healing and regeneration allowed us to identify amputation-specific genes. By clustering the expression profiles of these samples, we could detect three distinguishable phases of gene expression - early wound healing followed by a transition-phase leading to establishment of the limb development program, which correspond to the three phases of limb regeneration that had been defined by morphological criteria. By focusing on the transition-phase, we identified 93 strictly amputation-associated genes many of which are implicated in oxidative-stress response, chromatin modification, epithelial development or limb development. We further classified the genes based on whether they were or were not significantly expressed in the developing limb bud. The specific localization of 53 selected candidates within the blastema was investigated by in situ hybridization. In summary, we identified a set of genes that are expressed specifically during regeneration and are therefore, likely candidates for the regulation of blastema formation.

Historical aspects of Mexican psychiatry.

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Bayardo, Sergio Javier Villaseñor

2016-04-01

Mexican psychiatry initiated since pre-Hispanic times. Historically, treatments were a mixture of magic, science and religion. Ancient Nahuas had their own medical concepts with a holistic view of medicine, considering men and cosmos as a whole. The first psychiatric hospital appeared in 1566 and a more modern psychiatric asylum emerged until 1910. International exchanges of theoretical approaches started in the National University with the visit of Pierre Janet. There were other important figures that influenced Mexican psychiatry, such as Erich Fromm, Henri Ey, Jean Garrabé and Yves Thoret. Regarding Mexican psychiatrists, some of the most important contributors to Mexican psychiatry were José Luis Patiño Rojas, Manuel Guevara Oropeza and Ramón de la Fuente Muñiz. This article includes excerpts from "Clinical Psychiatry", a book by Patiño Rojas where he tries to understand and describe the inner world experienced by patients with schizophrenia; also, the thesis conducted by Guevara Oropeza ("Psychoanalisis"), which is a critical comparison between the theories of Janet and Freud. Finally, we include "The study of consciousness: current status" by Ramón de la Fuente, which leads us through the initial investigations concerning consciousness, its evolution, and the contributions made by psychology, philosophy and neurobiology.

Parent Group Education to ENABLE “Barrio” Parents

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Herman Curiel

2014-04-01

Full Text Available This paper describes a 1960s “War on Poverty” parent group education program that brought together three national private voluntary agencies with federal funding by the Office of Economic Opportunity (OEO. Project ENABLE (Education Neighborhood Action for a Better Living Environment sought to direct professional efforts to help/empower the poor and societal members of ethnic minority groups. Group education as a preventive modality was used to strengthen parents’ problem solving skills in their roles both as parents and as community leaders. The author describes his group leadership role together with that of the indigenous case aides who helped direct/enable the collective power of a group of poor Spanish speaking Mexican origin families living in barrios (neighborhoods of a major metropolitan southern city. Project ENABLE embraced a strengths-based perspective characteristic of social work’s historical empowerment traditions. Despite its brief existence, Project ENABLE functioned as a demonstration program in 62 communities across the United States. Ironically, its prevention focus and demonstration nature served to undermine its ability to compete with other OEO initiatives like Head Start and job training programs. The author cites a combination of historical and logistic factors that contributed to the short life and ultimate demise of a once promising outreach program.

Mexican energy policy and sustainability indicators

International Nuclear Information System (INIS)

Sheinbaum-Pardo, Claudia; Ruiz-Mendoza, Belizza Janet; Rodríguez-Padilla, Víctor

2012-01-01

The authors analyze the Mexican energy policy taking as reference the methodological framework for sustainable energy development proposed by the Economic Commission for Latin America and the Caribbean. This methodology takes eight related indicators to the social, environmental and economic dimensions in order to calculate a general sustainability indicator for the energy sector. In this methodology, the weight of each dimension is different; namely, the social and environmental issues have less relevance than the economic issues. The authors use this methodology because government institutions as the Department of Energy and the Department of Environment and Natural Resources have used some indicators from such a methodology to propose plans, programs, projects and bills. Authors know of the existence of other methodologies about sustainability. Nonetheless, opting for the Economic Commission for Latin America and the Caribbean's methodology is convenient because this organization is a respectable authority for civil servants from the Mexican institutions. Our objective is just to contrast the sustainability grade of the energy sector between 1990 and 2008 for Mexico whose government started reforms in the 1990s. It concludes that those reforms did not bring about a higher sustainability level for the energy sector. - Highlights: ► We used the OLADE, CEPAL and GTZ's methodology to calculate sustainability indicators for the Mexican energy sector. ► We studied the Mexican energy policy from 1990 to date and presented it. ► Currently, the Mexican energy sector is less sustainable than in 1990.

Business opportunities in the Mexican dairy industry

NARCIS (Netherlands)

Wijnands, J.H.M.; Armenta Gutierrez, B.M.; Poelarends, J.J.; Valk, van der O.M.C.

2010-01-01

This study explores the Mexican and Dutch business opportunities in the dairy industry in Mexico. The report discusses first the external environment of the Mexican dairy sector: the economic developments, the country's overall competitiveness, and the economic and agricultural policies. Next, it

Points for Improvement in Mexican Legislation on Safeguards

International Nuclear Information System (INIS)

Maciel Sánchez, S.; Carreño Padilla, A. L.

2015-01-01

The main goal of this paper is to underline the specific points needed still to be improved on safeguards in the Mexican legal framework. The problem: Mexico proposed the Tlatelolco Treaty which was before the TNP. So the Mexican legislation on safeguards should to be one of the best around the world, but there are still points to be improved, such as a specific regulation on the topic. Justification: Remembering that the exact sciences need of the law in order to be applied in a desirable way. I mean, the safeguards could be well conceived and well worked from the physics and mathematics point of view, but in order to be followed in any country, it is necessary the right legal framework. Hypothesis: What has Mexico now in its legislation on safeguards and what remains to be done (what is pending in the Mexican legal scope of the safeguards)? Objectives: – To propose legal solutions to correct the weakness of the Mexican legal framework on Safeguards; taking into account my own experience drafting the Mexican regulation on safeguards from 2008 for the Mexican Government in my nuclear law firm “Martínez and Maciel”. – To propose a legal framework on safeguards for Mexico as it is understood by the IAEA. – To update the legal frame work on safeguards in Mexico linking it to the Back end of the spent fuel. (Considering that sooner or later the Mexican Government will have to define its politic on this topic). (author)

Long-term surveillance plan for the Mexican Hat disposal site Mexican Hat, Utah

International Nuclear Information System (INIS)

1997-06-01

This long-term surveillance plan (LTSP) describes the U.S. Department of Energy's (DOE) long-term care program for the Uranium Mill Tailings Remedial Action (UMTRA) Project Mexican Hat, Utah, disposal site. This LSTP describes the long-term surveillance program the DOE will implement to ensure the Mexican Hat disposal site performs as designed and is cared for in a manner that protects the public health and safety and the environment. Before each disposal site is licensed for custody and long-term care, the Nuclear Regulatory Commission (NRC) requires the DOE to submit such a site-specific LTSP

Ontogeny of the VIP system in the gastro-intestinal tract of the Axolotl, Ambystoma mexicanum: successive appearance of co-existing PACAP and NOS.

Science.gov (United States)

Badawy, Gamal; Reinecke, Manfred

2003-03-01

Evidence for the presence and potential co-existence of vasoactive intestinal polypeptide (VIP), pituitary adenylate cyclase-activating polypeptide (PACAP) and nitric oxide synthase (NOS) in gastro-intestinal endocrine cells and/or nerve fibers is conflicting and very few results exist on development. This immunofluorescence study aims to clarify the appearance and localization of VIP, PACAP and NOS in the gastro-intestinal tract of the Axolotl, Ambystoma mexicanum, during ontogeny. VIP-immunoreactivity appeared in nerve fibers as early as on day 3 after hatching likely indicating a particular role, such as a trophic action, of VIP in very early development. PACAP-immunoreactivity was observed 3 days later within the VIP-immunoreactive (-IR) fibers. From this time on, VIP- and PACAP-immunoreactivity exhibited complete co-existence. VIP/PACAP-IR fibers were found throughout the gastro-intestinal tract. They were most prominent in the myenteric plexus and the muscle layers and less frequent in the submucosa. NOS-immunoreactivity appeared as late as at the 1st (64 days) juvenile stage in a subpopulation of the VIP/PACAP-IR fibers that contacted submucosal arteries. We found only very few VIP/PACAP-IR perikarya, indicating that part of the VIP/PACAP-IR fibers is of extrinsic origin. On day 12 and in the 1st and 2nd (104 days) juvenile stage, infrequent PACAP-IR entero-endocrine cells were noted, while neither VIP- nor NOS-immunoreactivity occurred in endocrine cells at any stage of development. The complete coexistence of neuronal PACAP- and VIP-immunoreactivities and their very early appearance in ontogeny may suggest important and coordinated roles of both peptides in the control of Axolotl gastro-intestinal activity, while the VIP/ PACAP/NOS-IR fibers may be involved in the regulation of submucosal blood flow.

A Turnover Model for the Mexican Maquiladoras.

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Maertz, Carl P.; Stevens, Michael J.; Campion, Michael A.

2003-01-01

From interviews with 47 Mexican maquiladora workers, a model of voluntary turnover was created and compared with models from the United States, Canada, England, and Australia. Despite similarities, the cultural and economic environment affected the precise content of antecedents in the Mexican model. (Contains 63 references.) (SK)

Familism, machismo and child rearing practices among Mexican Americans.

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Tamez, E G

1981-09-01

Mexican Americans form the 2nd largest minority group in the US. Fertility is 50% higher than in any other ethnic group. Income levels are inordinately low. In 1970, 42% of Mexican Americans were indigent, making approxiamtely 4200 annually. The Mexican American poor can be categorized into newly arrived aliens or 2nd or 3rd generation American citizens. In the 1st instance, the couple is young and English is not spoken. 2nd or 3rd generation Mexican Americans speak English. The persistent socioeconomic status of the Mexican American relates directly to the level of education. 52% of all Mexican Americans do not finish high school. Paz and Remos described the Mexican in terms of Adler's inferiority model. Murillo stated that to an individual, the family--whether nuclear or extended--is the center of life. The inherent responsibility is that the individual behave properly lest the family be disgraced. The family provides emotional and material security. Familism was seen as a deterrant to utilization of health care services, although some studies claim opposing views. Familism and occupational stability related positively to seeking medical care when ill. Hayden believed that supreme male dominance, individualism, pride, wife beating, aversion to contraceptives, and other characteristics were attributable to machismo. A predominant pattern in Mexican American culture is that of elders' ordering young men and women to establish obedience and male dominance. The husband represents authority and the wife-mother maintains a role of complete devotion to her husband and children. Role differentiation is taught implicitly and explicitly from infancy. Studies on the psychological differences between the sexes indicated that females were oppressed and had lower self esteem than males. 18-24 year old Mexican Americans are becoming less insistent upon strict separation of sex roles and are beginning to reject the traditional Mexican notion of masculine superiority. The word

Prediabetes, undiagnosed diabetes, and diabetes among Mexican adults: findings from the Mexican Health and Aging Study.

Science.gov (United States)

Kumar, Amit; Wong, Rebeca; Ottenbacher, Kenneth J; Al Snih, Soham

2016-03-01

The purpose of the study was to examine the prevalence and determinants of prediabetes, undiagnosed diabetes, and diabetes among Mexican adults from a subsample of the Mexican Health and Aging Study. We examined 2012 participants from a subsample of the Mexican Health and Aging Study. Measures included sociodemographic characteristics, body mass index, central obesity, medical conditions, cholesterol, high-density lipoprotein cholesterol, hemoglobin A1c, and vitamin D. Logistic regression was performed to identify factors associated with prediabetes, undiagnosed diabetes, and self-reported diabetes. Prevalence of prediabetes, undiagnosed, and self-reported diabetes in this cohort was 44.2%, 18.0%, and 21.4%, respectively. Participants with high waist-hip ratio (1.61, 95% confidence interval [CI] = 1.05-2.45) and high cholesterol (1.85, 95% CI = 1.36-2.51) had higher odds of prediabetes. Overweight (1.68, 95% CI = 1.07-2.64), obesity (2.38, 95% CI = 1.41-4.02), and high waist circumference (1.60, 95% CI = 1.06-2.40) were significantly associated with higher odds of having undiagnosed diabetes. Those residing in a Mexican state with high U.S. migration had lower odds of prediabetes (0.61, 95% CI = 0.45-0.82) and undiagnosed diabetes (0.53, 95% CI = 0.41-0.70). Those engaged in regular physical activity had lower odds of undiagnosed diabetes (0.74, 95% CI = 0.57-0.97). There is a high prevalence of prediabetes and undiagnosed diabetes among Mexican adults in this subsample. Findings suggest the need for resources to prevent, identify, and treat persons with prediabetes and undiagnosed diabetes. Copyright © 2016 Elsevier Inc. All rights reserved.

The Smell of Memories. A Mexican Migrant’s Search for Emotional Sustainability through Mexican Films.

OpenAIRE

Gabriela Coronado

2011-01-01

For more than 10 years living as a Mexican migrant, between two countries (Mexico and Australia), two cities (Mexico City and Sydney), and two social worlds (Mexican and multicultural Australian ‘families-friends’), I have been immersed in a systematic process of self observation and self reflection on my life in my country of destination. During this time I have explored my memories of place and their relationship with my emotional experiences, looking for strategies to continue to be connec...

[Mexican] Private-sector petroleum companies and agents

International Nuclear Information System (INIS)

1993-07-01

An overview is presented of the Mexican petroleum sector. The sector is largely controlled by the state company PEMEX and is not completely open to foreign participation and supply, however the trend towards privatization and open competition, combined with the drive for competitiveness of PEMEX operations in particular, is creating market opportunities for foreign suppliers of petroleum equipment and services. Detailed profiles are provided of 50 Mexican companies and their primary products and services, specific areas of expertise, client base, international experience, interest in Canada, other relevant information, and a contact person. A less detailed list is also provided of additional Mexican contacts, petroleum industry associations and chambers of commerce

"American" Abjection: "Chicanos," Gangs, and Mexican/Migrant Transnationality in Chicago

Science.gov (United States)

De Genova, Nicholas

2008-01-01

Crime and street violence often evoke racialized discourses about urban space. In this ethnographic research in Chicago, however, the disdain that many Mexican migrants articulated about street gangs principally concerned issues "internal" to the Mexican/Chicano community, notably a profound ambivalence about U.S.-born Mexicans and a…

[Dichotic perception of Mandarin third tone by Mexican Chinese learners].

Science.gov (United States)

Wang, Hongbin

2014-05-01

To investigate the relationship between the advantage ear (cerebral hemisphere) of Spanish-speaking Mexican learners and the third Chinese tone. Third tone Chinese vowel syllables were used as experimental materials with dichotic listening technology to test the Spanish-speaking Mexican Chinese learners (20-32 years old) who studied Chinese about 20 h. In terms of error rates to identify the third Chinese tone, the Spanish-speaking Mexican Chinese learners's reaction to the third tone suggested that their left ears were the advantageous ear (the right cerebral hemisphere) (Z=-2.091, P=0.036). The verbal information of tones influenced the perception of Mexican Chinese learners' mandarin tones. In the process of learning mandarin tones, Mexican Chinese learners gradually formed the category of tones.

DNA Methylation Dynamics Regulate the Formation of a Regenerative Wound Epithelium during Axolotl Limb Regeneration.

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Cristian Aguilar

Full Text Available The formation of a blastema during regeneration of an axolotl limb involves important changes in the behavior and function of cells at the site of injury. One of the earliest events is the formation of the wound epithelium and subsequently the apical epidermal cap, which involves in vivo dedifferentiation that is controlled by signaling from the nerve. We have investigated the role of epigenetic modifications to the genome as a possible mechanism for regulating changes in gene expression patterns of keratinocytes of the wound and blastema epithelium that are involved in regeneration. We report a modulation of the expression DNMT3a, a de novo DNA methyltransferase, within the first 72 hours post injury that is dependent on nerve signaling. Treatment of skin wounds on the upper forelimb with decitabine, a DNA methyltransferase inhibitor, induced changes in gene expression and cellular behavior associated with a regenerative response. Furthermore, decitabine-treated wounds were able to participate in regeneration while untreated wounds inhibited a regenerative response. Elucidation of the specific epigenetic modifications that mediate cellular dedifferentiation likely will lead to insights for initiating a regenerative response in organisms that lack this ability.

Generational Variations in Mexican-Origin Intermarriage

OpenAIRE

Cedillo, Rosalio

2015-01-01

This dissertation examines intermarriage across generations of the Mexican-origin population in order to better understand how this population is incorporating in U.S. society, and looks at parental migration status and parental nativity as factors that may impede or facilitate intermarriage incorporation. Using data from the Immigration and Intergenerational Mobility in Metropolitan Los Angeles (IIMMLA) survey the research shows that: the majority of intermarriages among the Mexican-origin ...

Diabetes is more lethal in Mexicans and Mexican Americans compared to non-Hispanic Whites

Science.gov (United States)

Hunt, Kelly J; Gonzalez, Maria Elena; Lopez, Ruy; Haffner, Steve M; Stern, Michael P; Gonzalez-Villalpando, Clicerio

2012-01-01

Purpose To examine the mortality risk associated with diabetes in the Mexico City Diabetes Study (MCDS) and the San Antonio Heart Study (SAHS). Methods Prospective cohorts conducted 1990-2007 in MCDS and 1979-2000 in SAHS. Mortality risk was examined using Cox proportional hazard models in 1,402 non-Hispanic whites (NHW), 1,907 U.S.-born Mexican Americans (MA), 444 Mexican-born MA, 2,281 Mexico City residents (MCR) between the ages of 35 and 64. Results Age- and sex-adjusted mortality HRs comparing U.S.-born MA, Mexican-born MA and MCR to NHW were 1.09 (95% CI: 0.86, 1.37), 1.23 (95% CI: 0.86, 1.76) and 0.97 (95% CI: 0.77, 1.23), respectively, in non-diabetic individuals; in contrast, mortality risk varied in diabetic individuals with respective HRs of 1.77 (95% CI: 1.20, 2.61), 1.08 (95% CI: 0.59, 1.97) and 2.27 (95% CI: 1.53, 3.35) (interaction p-value=0.0003). Excluding Mexican-born MA and non-diabetic individuals, controlling for medication use, insulin use, fasting glucose levels and duration of diabetes explained a significant proportion of the mortality differential (HRs relative to NHW were 1.31 (95% CI: 0.87, 1.98) in U.S.-born MA and 1.38 (95% CI: 0.89, 2.12) in MCR). Conclusions This study provides evidence that diabetes is more lethal in U.S.-born MA and MCR than in NHW. PMID:21840730

Neurotrophic regulation of fibroblast dedifferentiation during limb skeletal regeneration in the axolotl (Ambystoma mexicanum).

Science.gov (United States)

Satoh, Akira; Cummings, Gillian M C; Bryant, Susan V; Gardiner, David M

2010-01-15

The ability of animals to repair tissue damage is widespread and impressive. Among tissues, the repair and remodeling of bone occurs during growth and in response to injury; however, loss of bone above a threshold amount is not regenerated, resulting in a "critical-size defect" (CSD). The development of therapies to replace or regenerate a CSD is a major focus of research in regenerative medicine and tissue engineering. Adult urodeles (salamanders) are unique in their ability to regenerate complex tissues perfectly, yet like mammals do not regenerate a CSD. We report on an experimental model for the regeneration of a CSD in the axolotl (the Excisional Regeneration Model) that allows for the identification of signals to induce fibroblast dedifferentiation and skeletal regeneration. This regenerative response is mediated in part by BMP signaling, as is the case in mammals; however, a complete regenerative response requires the induction of a population of undifferentiated, regeneration-competent cells. These cells can be induced by signaling from limb amputation to generate blastema cells that can be grafted to the wound, as well as by signaling from a nerve and a wound epithelium to induce blastema cells from fibroblasts within the wound environment. Copyright 2009 Elsevier Inc. All rights reserved.

Stress Resilience among Border Mexican American Women

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Guinn, Bobby; Vincent, Vern; Dugas, Donna

2009-01-01

The purpose of this study was to identify factors distinguishing Mexican American women living near the U.S.-Mexican border who are resilient to the experience of stress from those who are not. The study sample consisted of 418 participants ranging in age from 20 to 61 years. Data were gathered through a self-report survey instrument composed of…

Crystal structure of axolotl (Ambystoma mexicanum) liver bile acid-binding protein bound to cholic and oleic acid.

Science.gov (United States)

Capaldi, Stefano; Guariento, Mara; Perduca, Massimiliano; Di Pietro, Santiago M; Santomé, José A; Monaco, Hugo L

2006-07-01

The family of the liver bile acid-binding proteins (L-BABPs), formerly called liver basic fatty acid-binding proteins (Lb-FABPs) shares fold and sequence similarity with the paralogous liver fatty acid-binding proteins (L-FABPs) but has a different stoichiometry and specificity of ligand binding. This article describes the first X-ray structure of a member of the L-BABP family, axolotl (Ambystoma mexicanum) L-BABP, bound to two different ligands: cholic and oleic acid. The protein binds one molecule of oleic acid in a position that is significantly different from that of either of the two molecules that bind to rat liver FABP. The stoichiometry of binding of cholate is of two ligands per protein molecule, as observed in chicken L-BABP. The cholate molecule that binds buried most deeply into the internal cavity overlaps well with the analogous bound to chicken L-BABP, whereas the second molecule, which interacts with the first only through hydrophobic contacts, is more external and exposed to the solvent. (c) 2006 Wiley-Liss, Inc.

Proteomic analysis of blastema formation in regenerating axolotl limbs

Directory of Open Access Journals (Sweden)

Nye Holly LD

2009-11-01

Full Text Available Abstract Background Following amputation, urodele salamander limbs reprogram somatic cells to form a blastema that self-organizes into the missing limb parts to restore the structure and function of the limb. To help understand the molecular basis of blastema formation, we used quantitative label-free liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS-based methods to analyze changes in the proteome that occurred 1, 4 and 7 days post amputation (dpa through the mid-tibia/fibula of axolotl hind limbs. Results We identified 309 unique proteins with significant fold change relative to controls (0 dpa, representing 10 biological process categories: (1 signaling, (2 Ca2+ binding and translocation, (3 transcription, (4 translation, (5 cytoskeleton, (6 extracellular matrix (ECM, (7 metabolism, (8 cell protection, (9 degradation, and (10 cell cycle. In all, 43 proteins exhibited exceptionally high fold changes. Of these, the ecotropic viral integrative factor 5 (EVI5, a cell cycle-related oncoprotein that prevents cells from entering the mitotic phase of the cell cycle prematurely, was of special interest because its fold change was exceptionally high throughout blastema formation. Conclusion Our data were consistent with previous studies indicating the importance of inositol triphosphate and Ca2+ signaling in initiating the ECM and cytoskeletal remodeling characteristic of histolysis and cell dedifferentiation. In addition, the data suggested that blastema formation requires several mechanisms to avoid apoptosis, including reduced metabolism, differential regulation of proapoptotic and antiapoptotic proteins, and initiation of an unfolded protein response (UPR. Since there is virtually no mitosis during blastema formation, we propose that high levels of EVI5 function to arrest dedifferentiated cells somewhere in the G1/S/G2 phases of the cell cycle until they have accumulated under the wound epidermis and enter mitosis in response to

Personality traits associated with success in Mexican exporter

Directory of Open Access Journals (Sweden)

Olga Leticia Gil Gaytan

2017-06-01

Full Text Available The objective of this research is to identify the personality traits associated with success in exporting by Mexican entrepreneurs in the Guadalajara metropolitan area. The main justification for carrying out this study is Mexico’s need to reduce its current dependence on manufacturing exports using foreign investment and increase the exports of Mexican companies. According to this study, there is association between export success and personality traits in successful Mexican exporters. With the spread of these findings, it is expected that both universities and business organizations will consider these results when selecting students for programs related to international venture.

Mexican immigration and the port-of-entry school.

Science.gov (United States)

Baca, R; Bryan, D; Mclean-bardwell, C; Gomez, F

1989-01-01

The results of an immigrant student census in a California port-of-entry school district are used to describe the educational backgrounds of Mexican immigrant students and to distinguish types of Mexican immigrant students by school entry patterns. Interviews with recently arrived Mexican immigrant parents reveal the educational and occupational expectations they hold for their children in the US. The study findings are used as a basis for raising policy questions and generating research issues. The most notable observation from the study is that the children of Mexican immigrants in La Entrada do not migrate once they are in school. Parents may be migrating back and forth between the US and Mexico, but children once in La Entrada do not leave the school to return to school in Mexico. The study suggests that the parents of immigrant students do not know how the US educational system works but they are interested in helping teachers educate their children.

United States -- Mexican joint ventures: A case history approach

Energy Technology Data Exchange (ETDEWEB)

Moore, N.L.; Chidester, R.J.; Hughes, K.R.; Fowler, R.A.

1993-03-01

Because the Mexican government has encouraged investment in Mexico by increasing the percentage of ownership of a Mexican business that a US company can hold, joint ventures are more attractive now than they had been in the past. This study provides preliminary information for US renewable energy companies who are interested in forming a joint venture with a Mexican company. This report is not intended to be a complete reference but does identifies a number of important factors that should be observed when forming a Mexican joint venture: (1)Successful joint ventures achieve the goals of each partner. (2)It is essential that all parties agree to the allocation of responsibilities. (3)Put everything in writing. (4)Research in depth the country or countries in which you are considering doing business.

Contemporary Fertility Patterns and First-Birth Timing among Mexican-Origin Women

Science.gov (United States)

Batson, Christie D.

2013-01-01

This article examines first-birth timing among Mexican women in the United States over two birth cohorts. Currently, Mexican women are one of a small group that maintains above-replacement fertility in the United States, contributing to both Mexican population growth and overall national population growth. Yet, the fertility timing of Mexican…

Anxiety disorders among Mexican Americans and non-Hispanic whites in Los Angeles.

Science.gov (United States)

Karno, M; Golding, J M; Burnam, M A; Hough, R L; Escobar, J I; Wells, K M; Boyer, R

1989-04-01

This report from the Los Angeles site of the NIMH Epidemiologic Catchment Area study reveals significant ethnic and national origin differences in lifetime prevalence rates for three out of six specific, DSM-III-defined anxiety disorders. In the case of simple phobia, United States-born Mexican Americans report higher rates than native non-Hispanic whites or immigrant Mexican Americans, the latter two groups having similar rates. Mexican Americans born in the United States had higher rates of agoraphobia than immigrant Mexican Americans, and non-Hispanic whites reported higher lifetime rates of generalized anxiety disorder compared with both immigrant and native Mexican Americans. Neither ethnic nor national origin differences in lifetime prevalence rates were found for panic disorder, social phobia, and obsessive-compulsive disorder. Selective migration is postulated as a potential factor influencing prevalence differences between native and immigrant Mexican Americans.

Virtual Genome Walking across the 32 Gb Ambystoma mexicanum genome; assembling gene models and intronic sequence.

Science.gov (United States)

Evans, Teri; Johnson, Andrew D; Loose, Matthew

2018-01-12

Large repeat rich genomes present challenges for assembly using short read technologies. The 32 Gb axolotl genome is estimated to contain ~19 Gb of repetitive DNA making an assembly from short reads alone effectively impossible. Indeed, this model species has been sequenced to 20× coverage but the reads could not be conventionally assembled. Using an alternative strategy, we have assembled subsets of these reads into scaffolds describing over 19,000 gene models. We call this method Virtual Genome Walking as it locally assembles whole genome reads based on a reference transcriptome, identifying exons and iteratively extending them into surrounding genomic sequence. These assemblies are then linked and refined to generate gene models including upstream and downstream genomic, and intronic, sequence. Our assemblies are validated by comparison with previously published axolotl bacterial artificial chromosome (BAC) sequences. Our analyses of axolotl intron length, intron-exon structure, repeat content and synteny provide novel insights into the genic structure of this model species. This resource will enable new experimental approaches in axolotl, such as ChIP-Seq and CRISPR and aid in future whole genome sequencing efforts. The assembled sequences and annotations presented here are freely available for download from https://tinyurl.com/y8gydc6n . The software pipeline is available from https://github.com/LooseLab/iterassemble .

Problems Faced by Mexican Asylum Seekers in the United States

Directory of Open Access Journals (Sweden)

J. Anna Cabot

2014-12-01

Full Text Available Violence in Mexico rose sharply in response to President Felipe Calderón’s military campaign against drug cartels which began in late 2006. As a consequence, the number of Mexicans who have sought asylum in the United States has grown significantly. In 2013, Mexicans made up the second largest group of defensive asylum seekers (those in removal proceedings in the United States, behind only China (EOIR 2014b. Yet between 2008 and 2013, the grant rate for Mexican asylum seekers in immigration court fell from 23 percent to nine percent (EOIR 2013, 2014b. This paper examines—from the perspective of an attorney who represented Mexican asylum seekers on the US-Mexico border in El Paso, Texas—the reasons for low asylum approval rates for Mexicans despite high levels of violence in and flight from Mexico from 2008 to 2013. It details the obstacles faced by Mexican asylum seekers along the US-Mexico border, including placement in removal proceedings, detention, evidentiary issues, narrow legal standards, and (effectively judicial notice of country conditions in Mexico. The paper recommends that asylum seekers at the border be placed in affirmative proceedings (before immigration officials, making them eligible for bond. It also proposes increased oversight of immigration judges.

NAFTA: The Mexican Economy, and Undocumented Migration

Science.gov (United States)

2011-10-28

NAFTA contributed to modest increases in Mexican formal employment since 1994. Since employment constitutes one of the chief factors affecting poverty...any other provision of law , no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a...FINAL 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE NAFTA , the Mexican Economy, and Undocumented Migration 5a

Mexican Art and Architecture Databases: Needs, Achievements, Problems.

Science.gov (United States)

Barberena, Elsa

At the international level, a lack of diffusion of Mexican art and architecture in indexes and abstracts has been detected. Reasons for this could be lack of continuity in publications, the use of the Spanish language, lack of interest in Mexican art and architecture, and sporadic financial resources. Nevertheless, even though conditions are not…

Metabolic responses to a traditional Mexican diet compared with a commonly consumed US diet in women of Mexican descent: a randomized crossover feeding trial.

Science.gov (United States)

Santiago-Torres, Margarita; Kratz, Mario; Lampe, Johanna W; Tapsoba, Jean De Dieu; Breymeyer, Kara L; Levy, Lisa; Villaseñor, Adriana; Wang, Ching-Yun; Song, Xiaoling; Neuhouser, Marian L

2016-02-01

Mexican immigrants are disproportionally affected by diet-related risk of metabolic dysfunction. Whether adhering to a traditional Mexican diet or adopting a US diet contributes to metabolic changes associated with future risk of type 2 diabetes and other chronic diseases has not been investigated. The purpose of this study was to test in a randomized crossover feeding trial the metabolic responses to a Mexican diet compared with a commonly consumed US diet. First- and second-generation healthy women of Mexican descent (n = 53) were randomly assigned in a crossover design to consume a Mexican or US diet for 24 d each, separated by a 28-d washout period. Diets were eucaloric and similar in macronutrient composition. The metabolic responses to diets were assessed by measuring fasting serum concentrations of glucose, insulin, insulin-like growth factor 1 (IGF-1), insulin-like growth factor binding protein 3 (IGFBP-3), adiponectin, C-reactive protein (CRP), and interleukin 6 (IL-6), as well as the homeostasis model assessment of insulin resistance (HOMA-IR) at the beginning and end of each period. Linear mixed models tested the intervention effect on the biomarkers, while adjusting for diet sequence, feeding period, baseline and washout biomarker concentrations, age, acculturation, and BMI. Compared with the US diet, the Mexican diet reduced insulin by 14% [geometric means (95% CIs): 9.3 (8.3, 10.3) compared with 8.0 (7.2, 8.9) μU/mL; P = 0.02], HOMA-IR by 15% [2.0 (1.8, 2.3) compared with 1.7 (1.6, 2.0); P = 0.02], and IGFBP-3 by 6% (mean ± SEM: 2420 ± 29 compared with 2299 ± 29 ng/mL; P diet. Compared with the commonly consumed US diet, the traditional Mexican diet modestly improved insulin sensitivity under conditions of weight stability in healthy women of Mexican descent, while having no impact on biomarkers of inflammation. This trial was registered at clinicaltrials.gov as NCT01369173. © 2016 American Society for Nutrition.

The Struggles of Solidarity: Chicana/o-Mexican Networks, 1960s–1970s

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Nydia A. Martinez

2015-07-01

Full Text Available Throughout the 1960s and 1970s, members of the Chicana/o Movement reached across class, borders, and ideologies to proclaim a political solidarity with the Mexican Left. Both, Chicana/os and Mexican activists expressed a narrative of political solidarity that encompassed a perceived shared experience of oppression and struggles for liberation. I contend, however, that both groups saw the source of their oppression and forms of resistance through different lenses. Chicana/o activists identified racism, discrimination, and cultural erasure with oppression, and they retrofit Mexican nationalism with political radicalism. In contrast, Mexican activists celebrated Marxist ideologies as radical political resistance against an increasing authoritarian government and associated Mexican nationalism with state repression and political manipulation.

The Mexican Revolution and health care or the health of the Mexican Revolution.

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Horn, J J

1985-01-01

Despite a victorious social revolution, a self-proclaimed "revolutionary" government, and a significant post-war economic growth, Mexico has not achieved a just or equitable social system. The Mexican Revolution led to the emergence of a new bureaucratic class whose "trickle-down" development strategy sacrificed social welfare to capital accumulation. Mexican morbidity and mortality patterns resemble those of more impoverished developing nations without revolutionary experience. The patterns of health care in Mexico reflect inequities and contradictions in the society and economy at large and flow from the erosion of the egalitarian aims of the revolution concomitant with the expansion of capitalism and the concentration of the benefits of "modernization" in the hands of privileged elites. Mexico's health problems are symptomatic of a general socio-economic malaise which questions the legitimacy of the Revolution.

Neuroticism, acculturation and the cortisol awakening response in Mexican American adults.

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Mangold, Deborah; Mintz, Jim; Javors, Martin; Marino, Elise

2012-01-01

Neuroticism is associated with greater susceptibility to the adverse effects of stress and greater exposure to the stressors associated with acculturation in U.S. born Mexican Americans. Neuroticism and acculturation have been associated with injury to crucial stress response systems and are known risk factors for certain mood and anxiety disorders. The purpose of the current study was to examine the effects of neuroticism, and acculturation on the cortisol awakening response (CAR) in healthy Mexican-American adults. Salivary cortisol samples were collected at awakening and 30, 45, and 60 min thereafter, on two consecutive weekdays from 59 healthy Mexican American adult males (26) and females (33), ages 18 to 38 years. Participants were assessed for level of neuroticism and acculturation. Data were analyzed using a mixed effects regression model with repeated measures at four time points. Results showed a significant Neuroticism×Acculturation×Time interaction. The CAR was virtually eliminated in highly acculturated Mexican Americans with greater Anglo orientation and high neuroticism compared with less acculturated Mexican Americans with greater Mexican orientation and lower neuroticism. Findings suggest that some Mexican Americans with high levels of neuroticism may be particularly susceptible to certain challenges and stressors associated with acculturation leading over time to the development of allostatic load, desensitization of the Hypothalamic CRF system and attenuation of the CAR. Copyright © 2011 Elsevier Inc. All rights reserved.

Regulation of Axolotl (Ambystoma mexicanum) Limb Blastema Cell Proliferation by Nerves and BMP2 in Organotypic Slice Culture.

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Lehrberg, Jeffrey; Gardiner, David M

2015-01-01

We have modified and optimized the technique of organotypic slice culture in order to study the mechanisms regulating growth and pattern formation in regenerating axolotl limb blastemas. Blastema cells maintain many of the behaviors that are characteristic of blastemas in vivo when cultured as slices in vitro, including rates of proliferation that are comparable to what has been reported in vivo. Because the blastema slices can be cultured in basal medium without fetal bovine serum, it was possible to test the response of blastema cells to signaling molecules present in serum, as well as those produced by nerves. We also were able to investigate the response of blastema cells to experimentally regulated changes in BMP signaling. Blastema cells responded to all of these signals by increasing the rate of proliferation and the level of expression of the blastema marker gene, Prrx-1. The organotypic slice culture model provides the opportunity to identify and characterize the spatial and temporal co-regulation of pathways in order to induce and enhance a regenerative response.

Regulation of Axolotl (Ambystoma mexicanum Limb Blastema Cell Proliferation by Nerves and BMP2 in Organotypic Slice Culture.

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Jeffrey Lehrberg

Full Text Available We have modified and optimized the technique of organotypic slice culture in order to study the mechanisms regulating growth and pattern formation in regenerating axolotl limb blastemas. Blastema cells maintain many of the behaviors that are characteristic of blastemas in vivo when cultured as slices in vitro, including rates of proliferation that are comparable to what has been reported in vivo. Because the blastema slices can be cultured in basal medium without fetal bovine serum, it was possible to test the response of blastema cells to signaling molecules present in serum, as well as those produced by nerves. We also were able to investigate the response of blastema cells to experimentally regulated changes in BMP signaling. Blastema cells responded to all of these signals by increasing the rate of proliferation and the level of expression of the blastema marker gene, Prrx-1. The organotypic slice culture model provides the opportunity to identify and characterize the spatial and temporal co-regulation of pathways in order to induce and enhance a regenerative response.

B Physics at the D0 experiment A Mexican review

International Nuclear Information System (INIS)

De La Cruz-Burelo, E.

2010-01-01

On April of 1992 a Mexican group from Cinvestav officially joined the D0 experiment, one of the two experiments in the Tevatron collider at Fermilab. The seed for this experimental group on high energy physics from Cinvestav was planted in Mexico in some measure by Augusto Garcia, to whom this workshop is in memorial. Augusto's efforts and support to groups dedicated to this area was clear and important. Some of these seeds have given origin to today's established Mexican groups on experimental high energy physics, one example of this is the Mexican group at D0. I present here a short review of some of the D0 results on which the Mexican group has contributed, emphasizing the last decade, which I have witnessed.

Description of Mexican Cleft Surgeons' Experience With Foreign Surgical Volunteer Missions in Mexico.

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Schoenbrunner, Anna R; Kelley, Kristen D; Buckstaff, Taylor; McIntyre, Joyce K; Sigler, Alicia; Gosman, Amanda A

2018-05-01

Mexican cleft surgeons provide multidisciplinary comprehensive cleft lip and palate care to children in Mexico. Many Mexican cleft surgeons have extensive experience with foreign, visiting surgeons. The purpose of this study was to characterize Mexican cleft surgeons' domestic and volunteer practice and to learn more about Mexican cleft surgeons' experience with visiting surgeons. A cross-sectional validated e-mail survey tool was sent to Mexican cleft surgeons through 2 Mexican plastic surgery societies and the Asociación Mexicana de Labio y Paladar Hendido y Anomalías Craneofaciales, the national cleft palate society that includes plastic and maxillofacial surgeons who specialize in cleft surgery. We utilized validated survey methodology, including neutral fact-based questions and repeated e-mails to survey nonresponders to maximize validity of statistical data; response rate was 30.6% (n = 81). Mexican cleft surgeons performed, on average, 37.7 primary palate repairs per year with an overall complication rate of 2.5%; 34.6% (n = 28) of respondents had direct experience with patients operated on by visiting surgeons; 53.6% of these respondents performed corrective surgery because of complications from visiting surgeons. Respondents rated 48% of the functional outcomes of visiting surgeons as "acceptable," whereas 43% rated aesthetic outcomes of visiting surgeons as "poor"; 73.3% of respondents were never paid for the corrective surgeries they performed. Thirty-three percent of Mexican cleft surgeons believe that there is a role for educational collaboration with visiting surgeons. Mexican cleft surgeons have a high volume of primary cleft palate repairs in their domestic practice with good outcomes. Visiting surgeons may play an important role in Mexican cleft care through educational collaborations that complement the strengths of Mexican cleft surgeons.

Economic reform, energy, and development: the case of Mexican manufacturing

International Nuclear Information System (INIS)

Aguayo, Francisco; Gallagher, K.P.

2005-01-01

Given increasing concern over global climate change and national security there is a burgeoning interest in examining the relationship between economic growth and energy use in developed and developing countries. More specifically, decoupling energy use per unit of gross domestic product (GDP) has fast come to be seen as in the interests of national economies and the world as a whole. Recent attention has been paid to the dramatic decreases in the energy intensity of the Chinese economy, which fell by 55% between 1975 and 1995. Do other developing economies follow similar trajectories? This paper examines the energy intensity of the Mexican economy for the period 1988-1998. Although the long-term trend in Mexican energy intensity is rising, the energy intensity of the Mexican economy began to decline in 1988. This paper explores the factors that have contributed to this reduction. Diminishing Mexican energy use per unit of GDP has been driven by significant decreases in industrial energy intensity. We show that these changes have resulted from changes in the composition of Mexican industrial structure, and technological change

A review of the Mexican national innovation system

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Samantha Rullán

2015-12-01

Full Text Available Governments and business leaders are increasingly aware of the role that innovation plays in economic growth, development and competitiveness. There are imperative challenges for Latin American countries, among them, poverty, social inclusion, sustainable development, climate change, natural disasters, productivity, improve the quality of education and health. Innovations are essential to drive economic growth and prosperity in the region. According to the Global Innovation Index (2015, Mexico is ranked 57th. Most of the research on innovation performance is mostly focused on technological innovation. Therefore, the main variables used, such as patents and number of scientific publications, do not always reflect the other types of innovations (i.e. business model, organizational, etc. that are developing in emerging markets. The aim of this paper is to analyze the Mexican innovation system using a broad concept with a focus on other types of innovation including cultural aspects to identify the main characteristics that distinguish and determine how innovation in Mexico is formed. Although the Mexican government has improved its institutional structure for innovation and its support policies, they need to evaluate programs and adjust incentive schemes based on performance to improve their innovation policy. Purpose – The purpose of this paper is to examine the Mexican National Innovation System using a broad concept with a focus on other types of innovation and including cultural aspects to identify some of the main characteristics that determine how innovation in Mexico is formed. Design/methodology/approach – The national innovation systems framework is used to review the Mexican innovation policy.A review of relevant literature on national innovation systems and Mexican innovation policies with data from the Global Innovation Index and INEGI were used for this paper. Findings – Higher private investment in R&D is needed to enhance

Contaminated Mexican steel incident

International Nuclear Information System (INIS)

1985-01-01

This report documents the circumstances contributing to the inadvertent melting of cobalt 60 (Co-60) contaminated scrap metal in two Mexican steel foundries and the subsequent distribution of contaminated steel products into the United States. The report addresses mainly those actions taken by US Federal and state agencies to protect the US population from radiation risks associated with the incident. Mexico had much more serious radiation exposure and contamination problems to manage. The United States Government maintained a standing offer to provide technical and medical assistance to the Mexican Government. The report covers the tracing of the source to its origin, response actions to recover radioactive steel in the United States, and return of the contaminated materials to Mexico. The incident resulted in significant radiation exposures within Mexico, but no known significant exposure within the United States. Response to the incident required the combined efforts of the Nuclear Regulatory Commission (NRC), Department of Energy, Department of Transportation, Department of State, and US Customs Service (Department of Treasury) personnel at the Federal level and representatives of all 50 State Radiation Control Programs and, in some instances, local and county government personnel. The response also required a diplomatic interface with the Mexican Government and cooperation of numerous commercial establishments and members of the general public. The report describes the factual information associated with the event and may serve as information for subsequent recommendations and actions by the NRC. 8 figures

Parents' Promotion of Psychological Autonomy, Psychological Control, and Mexican-American Adolescents' Adjustment

Science.gov (United States)

Sher-Censor, Efrat; Parke, Ross D.; Coltrane, Scott

2011-01-01

Mexican-American adolescents are at an elevated risk for adjustment difficulties. In an effort to identify parenting practices that can affect the adjustment of Mexican-American youth, the current study examined parents' promotion of psychological autonomy and parents' psychological control as perceived by Mexican-American early adolescents, and…

New tariffs confuse Mexican market

International Nuclear Information System (INIS)

Coeyman, M.

1992-01-01

Indelpro - the Grupo Alfa/Himont joint venture 150,000-m.t./year polypropylene (PP) plant in Altamira, Mexico - has been working to find its place in the Mexican market since coming onstream in March. At the same time, that market has been complicated by the imposition of import and export tariffs by the U.S. Department of Commerce early this fall. Commerce's accession to a 10% ad valorem tax on US PP exports to Mexico surprised some industry observers. The tariff is scheduled to be phased out within 10 years and is partly countermanded by a 5% tariff over a five-year period on Mexican PP exports to the US. But some market analysts say the arrangement is baffling

Problems Faced by Mexican Asylum Seekers in the United States

OpenAIRE

J. Anna Cabot

2014-01-01

Violence in Mexico rose sharply in response to President Felipe Calderón’s military campaign against drug cartels which began in late 2006. As a consequence, the number of Mexicans who have sought asylum in the United States has grown significantly. In 2013, Mexicans made up the second largest group of defensive asylum seekers (those in removal proceedings) in the United States, behind only China (EOIR 2014b). Yet between 2008 and 2013, the grant rate for Mexican asylum seekers in immigration...

Women's Networks and the Social Needs of Mexican Immigrants.

Science.gov (United States)

O'Connor, Mary I.

1990-01-01

Reports on the persistence of a two-tiered economic and political system that routinely excludes Mexican immigrants. Focuses on the predominantly female employees of a wholesale nursery in Carpinteria (California), who have adapted the Mexican tradition of "confianza"-based relationships to form networks that facilitate communication and…

The Mexican American in Higher Education: Implications for Educators.

Science.gov (United States)

Muhs, William F.; And Others

1979-01-01

Literature reviews suggest that Mexican-American students place more emphasis on cooperation and group than on individual achievement. Education may be enhanced when teachers reinforce "successful behavior." Problems may arise using U.S.-based theories of "democratic" leadership styles because Mexican-American culture places emphasis on…

The Mexican Health Paradox: Expanding the Explanatory Power of the Acculturation Construct

Science.gov (United States)

Horevitz, Elizabeth; Organista, Kurt C.

2013-01-01

The Mexican health paradox refers to initially favorable health and mental health outcomes among recent Mexican immigrants to the United States. The subsequent rapid decline in Mexican health outcomes has been attributed to the process of acculturation to U.S. culture. However, the construct of acculturation has come under significant criticism…

Opportunities - oil and gas development in the Mexican market

International Nuclear Information System (INIS)

1997-01-01

This review of business opportunities is intended as a guide for Alberta companies who are interested in investing or otherwise participating in the Mexican oil and gas industry. The guide provides a brief summary of Mexico, its political, legal and economic system, a brief review of the Mexican oil and gas industry, environmental legislation, the financial institutions, labour/management relations and overseas trade relations. Opportunities for Alberta firms in the Mexican resources industry are identified. Steps to follow for anyone contemplating business with Pemex, the state-owned oil company, are outlined and sources of assistance available to Alberta companies are reviewed. There are various lists of private consultants, Canadian banks in Mexico, accounting firms, customs brokers, freight forwarders and tips on Canadian and Mexican sources of financing. There is also a summary of commercial regulations between Pemex and its suppliers, and an organization chart of the Exploration and Production Branch of Petroleos Mexicanos. tabs., figs

Invisible Infantry: Mexicans in World War II

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Enrique Plasencia de la Parra

2003-04-01

Full Text Available This paper analyses the  participation of Mexican  and  Mexican- American troops in the United States army during World War II. Recruiting, discrimination, their  role  in the  armed forces  and their reinsertion into society once the war ended, are examined. Special emphasis is placed  on the  Hispanics  fight for their  civil and political rights that was carried on very actively by many War veterans.

Chicano-Mexican Cultural Assimilation and Anglo-Saxon Cultural Dominance.

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Menchaca, Martha

1989-01-01

Examines cultural assimilation in a Mexican and Chicano community in Santa Paula, California. Argues that the assumption of Anglo-Saxon superiority ascribed inferior social positions to Mexican-origin groups and generated conflict among these groups at times, but promoted intergroup unity when social conditions became intolerable. Contains 39…

Effect of water quality on the feeding ecology of axolotl Ambystoma mexicanum

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Diego de Jesus Chaparro-Herrera

2013-10-01

Full Text Available Ambystoma mexicanum, a highly endangered species, is endemic to lake Xochimilco (Mexico City, Mexico which currently is being negatively affected by the introduction of Oreochromis niloticus (Tilapia and water pollution. During the first weeks of development, when mortality is the highest, Ambystoma mexicanumdepends on a diet of zooplankton. The aim of this study was to check whether contamination levels in lake Xochimilco influence zooplankton consumption by similar size classes of A. mexicanum and Oreochromis niloticus. In this study, we analysed changes in the functional responses and prey preference of A. mexicanum and larval Tilapia in two media, one with filtered lake Xochimilco water and another one with reconstituted water. As prey we used cladocerans (Moina macrocopa, Alona glabra, Macrothrix triserialis and Simocephalus vetulus and ostracods (Heterocypris incongruens. Zooplankton was offered in 5 different densities, 10, 20, 40, 80, 160 ind./mL. Prey consumption by A. mexicanum varied in relation to the species offered and age of the larvae. From the first week to the eighth week prey consumption by A. mexicanum increased by 57%. Our functional response tests showed that regardless of the prey type, prey consumption by A. mexicanum was lower in the contaminated water from lake Xochimilco. Among the zooplankton offered in the contaminated environment predators preferred smaller and slower moving microcrustaceans such as Alona glabra and Heterocypris incongruens. Furthermore, O. niloticus preferred prey such as Moina macrocopa and Macrothrix triserialis in the contaminated medium and was more voracious than the axolotl. Our results indicate that both water quality of the lake and the presence of the more resistant exotic fish adversely impact the survival of this endangered amphibian.

Two decades of Mexican particle physics at Fermilab

International Nuclear Information System (INIS)

Roy Rubinstein

2002-01-01

This report is a view from Fermilab of Mexican particle physics at the Laboratory since about 1980; it is not intended to be a history of Mexican particle physics: that topic is outside the expertise of the writer. The period 1980 to the present coincides with the growth of Mexican experimental particle physics from essentially no activity to its current state where Mexican groups take part in experiments at several of the world's major laboratories. Soon after becoming Fermilab director in 1979, Leon Lederman initiated a program to encourage experimental physics, especially experimental particle physics, in Latin America. At the time, Mexico had significant theoretical particle physics activity, but none in experiment. Following a visit by Lederman to UNAM in 1981, a conference ''Panamerican Symposium on Particle Physics and Technology'' was held in January 1982 at Cocoyoc, Mexico, with about 50 attendees from Europe, North America, and Latin America; these included Lederman, M. Moshinsky, J. Flores, S. Glashow, J. Bjorken, and G. Charpak. Among the conference outcomes were four subsequent similar symposia over the next decade, and a formal Fermilab program to aid Latin American physics (particularly particle physics); it also influenced a decision by Mexican physicist Clicerio Avilez to switch from theoretical to experimental particle physics. The first physics collaboration between Fermilab and Mexico was in particle theory. Post-docs Rodrigo Huerta and Jose Luis Lucio spent 1-2 years at Fermilab starting in 1981, and other theorists (including Augusto Garcia, Arnulfo Zepeda, Matias Moreno and Miguel Angel Perez) also spent time at the Laboratory in the 1980s

Mobility and International Collaboration: Case of the Mexican Scientific Diaspora.

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Rafael Marmolejo-Leyva

Full Text Available We use a data set of Mexican researchers working abroad that are included in the Mexican National System of Researchers (SNI. Our diaspora sample includes 479 researchers, most of them holding postdoctoral positions in mainly seven countries: USA, Great Britain, Germany, France, Spain, Canada and Brazil. Their research output and impact is explored in order to determine their patterns of production, mobility and scientific collaboration as compared with previous studies of the SNI researchers in the periods 1991-2001 and 2003-2009. Our findings confirm that mobility has a strong impact on their international scientific collaboration. We found no substantial influence among the researchers that got their PhD degrees abroad from those trained in Mexican universities. There are significant differences among the areas of knowledge studied: biological sciences, physics and engineering have better production and impact rates than mathematics, geosciences, medicine, agrosciences, chemistry, social sciences and humanities. We found a slight gender difference in research production but Mexican female scientists are underrepresented in our diaspora sample. These findings would have policy implications for the recently established program that will open new academic positions for young Mexican scientists.

Mobility and International Collaboration: Case of the Mexican Scientific Diaspora.

Science.gov (United States)

Marmolejo-Leyva, Rafael; Perez-Angon, Miguel Angel; Russell, Jane M

2015-01-01

We use a data set of Mexican researchers working abroad that are included in the Mexican National System of Researchers (SNI). Our diaspora sample includes 479 researchers, most of them holding postdoctoral positions in mainly seven countries: USA, Great Britain, Germany, France, Spain, Canada and Brazil. Their research output and impact is explored in order to determine their patterns of production, mobility and scientific collaboration as compared with previous studies of the SNI researchers in the periods 1991-2001 and 2003-2009. Our findings confirm that mobility has a strong impact on their international scientific collaboration. We found no substantial influence among the researchers that got their PhD degrees abroad from those trained in Mexican universities. There are significant differences among the areas of knowledge studied: biological sciences, physics and engineering have better production and impact rates than mathematics, geosciences, medicine, agrosciences, chemistry, social sciences and humanities. We found a slight gender difference in research production but Mexican female scientists are underrepresented in our diaspora sample. These findings would have policy implications for the recently established program that will open new academic positions for young Mexican scientists.

The North American Free Trade Agreement (NAFTA) and Mexican nursing.

Science.gov (United States)

Squires, Allison

2011-03-01

In the context of nurse migration, experts view trade agreements as either vehicles for facilitating migration or as contributing to brain-drain phenomena. Using a case study design, this study explored the effects of the North American Free Trade Agreement (NAFTA) on the development of Mexican nursing. Drawing results from a general thematic analysis of 48 interviews with Mexican nurses and 410 primary and secondary sources, findings show that NAFTA changed the relationship between the State and Mexican nursing. The changed relationship improved the infrastructure capable of producing and monitoring nursing human resources in Mexico. It did not lead to the mass migration of Mexican nurses to the United States and Canada. At the same time, the economic instability provoked by the peso crisis of 1995 slowed the implementation of planned advances. Subsequent neoliberal reforms decreased nurses' security as workers by minimizing access to full-time positions with benefits, and decreased wages. This article discusses the linkages of these events and the effects on Mexican nurses and the development of the profession. The findings have implications for nursing human resources policy-making and trade in services.

Contact with the Dead, Religion, and Death Anxiety among Older Mexican Americans

Science.gov (United States)

Krause, Neal; Bastida, Elena

2012-01-01

The purpose of this study is to see if contact with the dead is associated with lower death anxiety among older Mexican Americans. The data come from a nationwide survey of older Mexican Americans (N = 1,005). The study model specifies that (a) older Mexican Americans who have experienced contact with the dead are more likely to see the…

The Mexican mesozoic uranium province: its distribution and metallogeny

International Nuclear Information System (INIS)

Bazan B, S.

1981-01-01

The distribution of uranium scattered in sedimentary terrains of the continental jurassic such as those found in the Tlaxiaco-Guerrero Basin encourage the outlook for uncovering extensive new deposits of strato-bound uranium belonging to the Mexican mesozoic in other structurally similar intercratonic basins. Stratographic and paleographic structural references define the simultaneous evolution of five sedimentary basins during the Mexican geotechtonic cycle: 1. the Tlaxiaco-Guerrero basin, 2. the Huayacocotla basin, 3. the Gulf of Sabinas basin, 4. the Chihuahua basin and 5. the Sonora basin. From the various lithostratographic formations in them we favourably infer the presence of intermountainous mesozoic concentrations of uranium sediments leached from crystalline precambric packets and from nevadian plutonites and volcanic rocks. During the metallogeny process described under the techtonic evolution of the Mexican structural belt, the presence is established of extensive terciary hydrothermal uranium deposits in the districts of Aldama, Chihuahua; Coneto-El Rodeo, Durango; Vizarron de Montes, Queretaro; Tlaucingo, Puebla; Los Amoles, Sonora; El Picacho, Sonora; Amalia Margarita, Coahuila; etc., scattered in sandstones and sinters of the continental mesozoic and shifted during the postorogenic phase of the Mexican geotectonic cycle. The extensive mesozoic province defined within the Mexican territory favourable to large deposits of uranium, scattered and strato-bound in triassic, jurassic and cretaceous sandstone and sinters, could resolve future demands for energetics within a modified philosophy and resourceful policy of regional mining. (author)

Neurotrophic regulation of epidermal dedifferentiation during wound healing and limb regeneration in the axolotl (Ambystoma mexicanum).

Science.gov (United States)

Satoh, A; Graham, G M C; Bryant, S V; Gardiner, D M

2008-07-15

Adult urodeles (salamanders) are unique in their ability to regenerate complex organs perfectly. The recently developed Accessory Limb Model (ALM) in the axolotl provides an opportunity to identify and characterize the essential signaling events that control the early steps in limb regeneration. The ALM demonstrates that limb regeneration progresses in a stepwise fashion that is dependent on signals from the wound epidermis, nerves and dermal fibroblasts from opposite sides of the limb. When all the signals are present, a limb is formed de novo. The ALM thus provides an opportunity to identify and characterize the signaling pathways that control blastema morphogenesis and limb regeneration. In the present study, we have utilized the ALM to identity the buttonhead-like zinc-finger transcription factor, Sp9, as being involved in the formation of the regeneration epithelium. Sp9 expression is induced in basal keratinocytes of the apical blastema epithelium in a pattern that is comparable to its expression in developing limb buds, and it thus is an important marker for dedifferentiation of the epidermis. Induction of Sp9 expression is nerve-dependent, and we have identified KGF as an endogenous nerve factor that induces expression of Sp9 in the regeneration epithelium.

The role of familism in weight loss treatment for Mexican American women.

Science.gov (United States)

McLaughlin, Elizabeth A; Campos-Melady, Marita; Smith, Jane Ellen; Serier, Kelsey N; Belon, Katherine E; Simmons, Jeremiah D; Kelton, Katherine

2017-10-01

Mexican American women are disproportionately affected by overweight/obesity and the health complications accompanying them, but weight loss treatments are less successful in this ethnic group. High levels of familism, a value reflecting obligation to family that supersedes attention to oneself, interfere with weight loss for Mexican American women. This mixed methods study investigated overweight Mexican American women's beliefs about how familism, and Mexican American culture, might hinder weight loss success, and how treatments might be culturally adapted. Results suggest a need to support women in their commitment to family while also helping them make changes. Recommendations for culturally adapted treatments are made.

Ion channel signaling influences cellular proliferation and phagocyte activity during axolotl tail regeneration.

Science.gov (United States)

Franklin, Brandon M; Voss, S Randal; Osborn, Jeffrey L

2017-08-01

Little is known about the potential for ion channels to regulate cellular behaviors during tissue regeneration. Here, we utilized an amphibian tail regeneration assay coupled with a chemical genetic screen to identify ion channel antagonists that altered critical cellular processes during regeneration. Inhibition of multiple ion channels either partially (anoctamin1/Tmem16a, anoctamin2/Tmem16b, K V 2.1, K V 2.2, L-type Ca V channels and H/K ATPases) or completely (GlyR, GABA A R, K V 1.5 and SERCA pumps) inhibited tail regeneration. Partial inhibition of tail regeneration by blocking the calcium activated chloride channels, anoctamin1&2, was associated with a reduction of cellular proliferation in tail muscle and mesenchymal regions. Inhibition of anoctamin 1/2 also altered the post-amputation transcriptional response of p44/42 MAPK signaling pathway genes, including decreased expression of erk1/erk2. We also found that complete inhibition via voltage gated K + channel blockade was associated with diminished phagocyte recruitment to the amputation site. The identification of H + pumps as required for axolotl tail regeneration supports findings in Xenopus and Planaria models, and more generally, the conservation of ion channels as regulators of tissue regeneration. This study provides a preliminary framework for an in-depth investigation of the mechanistic role of ion channels and their potential involvement in regulating cellular proliferation and other processes essential to wound healing, appendage regeneration, and tissue repair. Copyright © 2017 Elsevier B.V. All rights reserved.

Mexican Identification. Project Mexico.

Science.gov (United States)

Castellano, Rita

This document presents an outline and teacher's guide for a community college-level teaching module in Mexican identification, designed for students in introductory courses in the social sciences. Although intended specifically for cultural anthropology, urban anthropology, comparative social organization and sex roles in cross-cultural…

The Dissolution of the Mexican-American Border and Redefinition of Chicano/a /Mexican Identity in Leslie Marmon Silko's Almanac of the Dead

DEFF Research Database (Denmark)

Harding, David

2006-01-01

In Leslie Marmon Silko's Almanac of the Dead, notions of Mexican identity are deconstructed. This article analyzes how Silko, through a variety of characters and sub-plotlines, brings to the surface hidden tensions in the contsruction of Mexican identity through the melding of the sangre limpia...

Long-term surveillance plan for the Mexican Hat disposal site Mexican Hat, Utah

International Nuclear Information System (INIS)

1997-05-01

This long-term surveillance plan (LTSP) describes the U.S. Department of Energy's (DOE) long-term care program for the Uranium Mill Tailings Remedial Action (UMTRA) Project Mexican Hat, Utah, disposal site. The U.S. Nuclear Regulatory Commission (NRC) has developed regulations for the issuance of a general license for the custody and long-term care of UMTRA Project disposal sites in 10 CFR Part 40. The purpose of this general license is to ensure that the UMTRA Project disposal sites will be cared for in a manner that protects the public health and safety and the environment. Before each disposal site is licensed, the NRC requires the DOE to submit a site-specific LTSP. The DOE prepared this LTSP to meet this requirement for the Mexican Hat disposal site. The general license becomes effective when the NRC concurs with the DOE's determination of completion of remedial action for the disposal site and the NRC formally accepts this LTSP. This LTSP describes the long-term surveillance program the DOE will implement to ensure that the Mexican Hat disposal site performs as designed. The program is based on two distinct types of activities: (1) site inspections to identify potential threats to disposal cell integrity, and (2) monitoring of selected seeps to observe changes in flow rates and water quality. The LTSP is based on the UMTRA Project long-term surveillance program guidance and meets the requirements of 10 CFR section 40.27(b) and 40 CFR section 192.03. 18 refs., 6 figs., 1 tab

Scale and scope economies in Mexican private medical units.

Science.gov (United States)

Keith, Jorge; Prior, Diego

2014-01-01

To evaluate technical efficiency and potential presence of scale and scope economies in Mexican private medical units (PMU) that will improve management decisions. We used data envelopment analysis methods with inputs and outputs for 2 105 Mexican PMU published in 2010 by the Instituto Nacional de Estadística y Geografía from the "Estadística de Unidades Médicas Privadas con Servicio de Hospitalización (PEC-6-20-A)" questionnaire. The application of the models used in the paper found that there is a marginal presence of economies of scale and scope in Mexican PMU. PMU in Mexico must focus to deliver their services on a diversified structure to achieve technical efficiency.

Cultural Values, U.S. Neighborhood Danger, and Mexican American Parents' Parenting

Science.gov (United States)

White, Rebecca M. B.; Zeiders, Katharine H.; Gonzales, Nancy A.; Tein, Jenn-Yun; Roosa, Mark W.

2013-01-01

To begin accounting for cultural and contextual factors related to child rearing among Mexican American parents we examined whether parents' Mexican American cultural values and perceptions of neighborhood danger influenced patterns of parenting behavior in two-parent Mexican-origin families living in the U.S. To avoid forcing Mexican American parents into a predefined model of parenting styles, we used latent profile analysis to identify unique patterns of responsiveness and demandingness among mothers and fathers. Analyses were conducted using parent self-reports on parenting and replicated with youth reports on mothers' and fathers' parenting. Across reporters most mothers and fathers exhibited a pattern of responsiveness and demandingness consistent with authoritative parenting. A small portion of parents exhibited a pattern of less-involved parenting. None of the patterns were indicative of authoritarianism. There was a modicum of evidence for no nonsense parenting among fathers. Both neighborhood danger and parents' cultural values were associated with the likelihood of employing one style of parenting over another. The value of using person-centered analytical techniques to examine parenting among Mexican Americans is discussed. PMID:23750519

Mexican-Origin Women's Employment Instability. Working Paper No. 51.

Science.gov (United States)

De Anda, Roberto M.

This paper compares the causes and consequences of employment instability among Mexican-origin women, White women, and White men. Data came from the work experience supplement in the March 1995 file of the Current Population Survey for a sample that included 1,399 Mexican-origin women, 17,092 White women, and 24,440 White men. All were experienced…

Identifying Strategic Groups: An Assessment in Mexican Franchises

Directory of Open Access Journals (Sweden)

Cesario Armando Flores Villanueva

2017-07-01

Full Text Available The formation of strategic groups in the franchising sector has been previously documented in the context of different countries. Our proposal is the franchise industry in Mexico should be formed by groups of differentiated franchisors. The identification and analysis of the different strategic groups formed in the franchise system of the Mexican market is the objective of this research. Our evaluation was performed using the factor analysis technique in a sample of 167 franchises of national origin. Seven strategic dimensions supported by the theory of scarce resources and agency theory make up the existence of differentiated groups of franchisors in the Mexican market. Our research confirmed the identification of five strategic groups called: rapid growth, converters, experienced and international franchisors, high entry fees and expensive conservatives, which use differentiated strategies to compete in the Mexican market.

Transformative, Mixed Methods Checklist for Psychological Research with Mexican Americans

Science.gov (United States)

Canales, Genevieve

2013-01-01

This is a description of the creation of a research methods tool, the "Transformative, Mixed Methods Checklist for Psychological Research With Mexican Americans." For conducting literature reviews of and planning mixed methods studies with Mexican Americans, it contains evaluative criteria calling for transformative mixed methods, perspectives…

Storytelling in Mexican Homes: Connections between Oral and Literacy Practices

Science.gov (United States)

Reese, Leslie

2012-01-01

The study focuses on storytelling among Mexican families, documenting the frequency of storytelling in the homes of working- and middle-class Mexican families, the range of topics of the stories, characteristics and genres of stories, and intergenerational continuity of storytelling practices. Also examined are potential associations between…

Supplement to the UMTRA Project water sampling and analysis plan, Mexican Hat, Utah

International Nuclear Information System (INIS)

1995-09-01

This water sampling and analysis plan (WSAP) supplement supports the regulatory and technical basis for water sampling at the Mexican Hat, Utah, Uranium Mill Tailings Remedial Action (UMTRA) Project site, as defined in the 1994 WSAP document for Mexican Hat (DOE, 1994). Further, the supplement serves to confirm our present understanding of the site relative to the hydrogeology and contaminant distribution as well as our intention to continue to use the sampling strategy as presented in the 1994 WSAP document for Mexican Hat. Ground water and surface water monitoring activities are derived from the US Environmental Protection Agency regulations in 40 CFR Part 192 (1991) and 60 FR 2854 (1995). Sampling procedures are guided by the UMTRA Project standard operating procedures (JEG, n.d.), the Technical Approach Document (DOE, 1989), and the most effective technical approach for the site. Additional site-specific documents relevant to the Mexican Hat site are the Mexican Hat Long-Term Surveillance Plan (currently in progress), and the Mexican Hat Site Observational Work Plan (currently in progress)

Scale and scope economies in Mexican private medical units

Directory of Open Access Journals (Sweden)

Jorge Keith

2014-07-01

Full Text Available Objective. To evaluate technical efficiency and potential presence of scale and scope economies in Mexican private medical units (PMU that will improve management decisions. Materials and methods. We used data envelopment analysis methods with inputs and outputs for 2 105 Mexican PMU published in 2010 by the Instituto Nacional de Estadística y Geografía from the “Estadística de Unidades Médicas Privadas con Servicio de Hospitalización (PEC-6-20-A” questionnaire. Results. The application of the models used in the paper found that there is a marginal presence of economies of scale and scope in Mexican PMU. Conclusions. PMU in Mexico must focus to deliver their services on a diversified structure to achieve technical efficiency.

Volunteer work in the church among older Mexican Americans.

Science.gov (United States)

Krause, Neal; Hayward, R David

2012-07-01

The purpose of this study is to identify the factors that influence the amount of volunteer work that older Mexican Americans perform in the place where they worship. The relationship between religion and volunteering is viewed from a social identity perspective. Data from a nationally representative sample of older Mexican Americans suggest that Evangelical/Pentecostal church members spend more time performing volunteer work at church than older Mexican Americans who affiliate with other denominations. Moreover, the findings indicate that the difference in the amount of volunteering between the two groups can largely be explained by differences in the nature of the spiritual support that Evangelical/Pentecostal receive from their fellow church members as well as depth of their commitment to their faith.

Deconstructive humour: subverting Mexican and Chicano stereotypes in ‘Un Día Sin Mexicanos’

OpenAIRE

Barrow, Sarah

2012-01-01

a long time, US cinema developed unshakeable stereotypes of Mexican ‘otherness’, with characters of Mexican cultural and ethnic heritage stigmatised as criminals or as sensual objects of desire. Filmmakers in Mexico, meanwhile, treated Mexican Americans as misfits who belonged nowhere, or ignored them and their complex experience completely. The emergence of a distinct ‘Chicano cinema’ in the 1960s allowed for the development of a more powerful set of images of Mexican Americans, exploiting t...

THE MEXICAN CALORIE ALLOCATION AMONG THE WORKING CLASS IN THE AMERICAN WEST, 1870-1920

Directory of Open Access Journals (Sweden)

Scott Alan Carson

2015-06-01

Full Text Available When measures for material conditions are sparse or unreliable, height and weight measurements are now widely accepted proxies that reflect changing economic conditions. This study uses two biological measurements related to height and weight: the basal metabolic rate (BMR and calorie accounting. BMRs and calories of Mexicans in the American West remained constant, indicating that their diets did not vary with United States economic development, but Mexican BMRs and diets varied with occupations. Farmers and unskilled workers had greater BMRs and received more calories per day than workers in other occupations. During much of the late 19th and early 20th centuries, Mexicans born in Mexico received fewer calories in the US than Mexicans born in the West. Mexican nutrition and diets also did not vary by residence within the US, indicating that Mexican diets were similar across western states.

Mexican experience on migration and development 1990-2013

Directory of Open Access Journals (Sweden)

Rodolfo García Zamora

Full Text Available After 40 years of a long rising emigration from Mexico to the United States, the number of Mexicans increased to 12 million in 2006, while the increased input of remittances reached $26 million dollars in 2007. Yet, the increasing migration and remittances mainly in Zacatecas and Michoacan states do not achieve economic and social development because of the persistent backwardness, unemployment and marginalization. It demands the need for new Policies of Development, Migration and Human Rights that allow exercising the right to not emigrate in a medium term. Positive products of this long migration are the Mexican Migrant Clubs and their Federations that elaborated the concrete development proposals. Whereas, the possibility that these proposals can become a Development, Migration and Human Rights, Comprehensive and Long Term State Policy will depend on the capacity and participation of Mexican Civil Society and the Transnational Communities in both countries.

Effect of acculturation and mutuality on family loyalty among Mexican American caregivers of elders.

Science.gov (United States)

Kao, Hsueh-Fen S; An, Kyungeh

2012-06-01

Informal family care for elders is conventional in Mexican American communities despite increasing intergenerational gaps in filial values. In our study, we explored whether acculturation and dyadic mutuality, as perceived by Mexican American family caregivers, explain the caregivers' expectations of family loyalty toward elderly relatives. A nonexperimental, correlational design with convenience sampling was used in El Paso, Texas, from October 2007 to January 2008. Three bilingual promotoras collected data from 193 Mexican American adult caregivers of community-dwelling elders using three scales designed for Mexican Americans: the Acculturation Rating Scale for Mexican Americans II-Short Form, the Mutuality Scale, and the Expectations of Family Loyalty of Children Toward Elderly Relatives Scale. Confirmatory factor analysis was used to analyze the data. Acculturation had a marginal effect (r = .21, p loyalty toward elderly relatives. There was no significant correlation between acculturation and mutuality (r = .05). Although Mexican American caregivers with strong Mexican orientation may have high expectations of family loyalty toward elderly relatives, mutuality exhibits more significant effects on expectations. Among Mexican Americans, mutuality between the caregiving dyad, as perceived by caregivers, may be a better predictor of filial values than caregivers' acculturation alone. It may be useful to incorporate the dual paradigm of acculturation and mutuality into immigrant family care for elderly relatives. © 2012 Sigma Theta Tau International.

Energy-urban transition: The Mexican case

International Nuclear Information System (INIS)

Paez, Armando

2010-01-01

In this paper I present a study regarding the institutional conditions of Mexican cities based on a post-petroleum urban model that considers transport, architecture, urban planning and land use, renewable energy sources, energy saving and efficiency, and urban metabolism issues. The model was constructed with recommendations of authors and organizations that have analysed the energy dimension of cities under an energy-availability, environmental or petroleum-independent view. To make the study I sent a questionnaire to some local governments of all the country. The information indicates that Mexican cities do not have institutional conditions to manage the urban-energy transition that signify the end of cheap oil and the peak of world oil production.

Cultural values, U.S. neighborhood danger, and Mexican American parents' parenting.

Science.gov (United States)

White, Rebecca M B; Zeiders, Katharine H; Gonzales, Nancy A; Tein, Jenn-Yun; Roosa, Mark W

2013-06-01

To begin accounting for cultural and contextual factors related to child rearing among Mexican American parents we examined whether parents' Mexican American cultural values and perceptions of neighborhood danger influenced patterns of parenting behavior in two-parent Mexican-origin families living in the U.S. To avoid forcing Mexican American parents into a predefined model of parenting styles, we used latent profile analysis to identify unique patterns of responsiveness and demandingness among mothers and fathers. Analyses were conducted using parent self-reports on parenting and replicated with youth reports on mothers' and fathers' parenting. Across reporters, most mothers and fathers exhibited a pattern of responsiveness and demandingness consistent with authoritative parenting. A small portion of parents exhibited a pattern of less-involved parenting. None of the patterns were indicative of authoritarianism. There was a modicum of evidence for no nonsense parenting among fathers. Both neighborhood danger and parents' cultural values were associated with the likelihood of employing one style of parenting over another. The value of using person-centered analytical techniques to examine parenting among Mexican Americans is discussed. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Genetic ancestry in relation to the metabolic response to a US versus traditional Mexican diet: a randomized crossover feeding trial among women of Mexican descent.

Science.gov (United States)

Santiago-Torres, M; De Dieu Tapsoba, J; Kratz, M; Lampe, J W; Breymeyer, K L; Levy, L; Song, X; Villaseñor, A; Wang, C-Y; Fejerman, L; Neuhouser, M L; Carlson, C S

2017-03-01

Certain populations with a large proportion of indigenous American (IA) genetic ancestry may be evolutionarily adapted to traditional diets high in legumes and complex carbohydrates, and may have a detrimental metabolic response to US diets high in refined carbohydrates and added sugars. We tested whether IA ancestry modified the metabolic response to a US versus traditional Mexican diet in a controlled dietary intervention. First and second generation Mexican immigrant women (n=53) completed a randomized crossover feeding trial testing the effects of a US versus traditional Mexican diet. The metabolic response to the diets was measured by fasting serum concentrations of glucose, insulin, insulin-like growth factor-1 (IGF-1), IGF-binding protein-3 (IGFBP-3), adiponectin, C-reactive protein, interleukin-6 and computed homeostasis model assessment for insulin resistance (HOMA IR ). Blood collected at baseline was used for genotyping, and estimation of African, European and IA ancestries with the use of 214 ancestry informative markers. The genetic ancestral background was 56% IA, 38% European and 6% African. Women in the highest IA ancestry tertile (>62%) were shorter in height, less educated and less acculturated to the US lifestyle, and tended to have higher waist-to-hip ratio compared with women in the middle and lowest IA ancestry tertiles, respectively. Compared with the US diet, the traditional Mexican diet tended to reduce glucose, insulin, IGF-1, IGFBP-3 and HOMA IR among women in the middle IA ancestry group (IA ancestry ⩽45-62%), whereas having no effect on biomarkers related to inflammation. We observed modest interactions between IA ancestry and the metabolic response to a US versus traditional Mexican diet among Mexican immigrant women.

'He supported me 100%': Mexican-immigrant fathers, daughters, and adolescent sexual health.

Science.gov (United States)

Coleman-Minahan, Kate; Samari, Goleen

2018-02-19

First and second generation Mexican-origin adolescents in the U.S. face social and economic disadvantage and sexual health disparities. Although fathers can support child and adolescent development, the literature has portrayed Mexican-origin immigrant fathers as emotionally distant and sexist. This study aims to treat migration as a social determinant of health to examine father-daughter relationships and adolescent sexual health in Mexican-origin immigrant families. Integrating qualitative data from life history interviews with 21 Mexican-origin young women in immigrant families with quantitative data on first and second generation Mexican-origin young women in the National Longitudinal Study of Adolescent to Adult Health, this study describes father-daughter relationships, examines the association between father-daughter relationships and daughters' early sexual initiation, and considers the impact of migration on the father-daughter relationship and sexual health among Mexican-origin young women. Qualitative data identify four types of father-daughter relationships: 'good,' hostile, distant, and conflicted. Supporting the qualitative patterns, quantitative data find that positive or 'good' father-daughter relationship quality is significantly associated with reduced risk of early sexual initiation. Importantly, father-daughter separation across borders and economic inequality facing immigrant families is associated with hostile or distant father-daughter relationship quality and increased risk of early sexual initiation. Reports of good father-daughter relationships are common and may protect against early sexual initiation in Mexican-origin immigrant families. Policies that keep families together and reduce economic inequality among immigrants may also reduce sexual health disparities among immigrant adolescents.

Evaluation of expressed emotion in schizophrenia: a comparison of Caucasians and Mexican-Americans.

Science.gov (United States)

Kopelowicz, Alex; Zarate, Roberto; Gonzalez, Veronica; Lopez, Steven R; Ortega, Paula; Obregon, Nora; Mintz, Jim

2002-05-01

Social desirability, while a recognized source of respondent bias among Mexican-Americans, has not been evaluated as an explanation for the lower rate of high expressed emotion (EE) found in the family members of Mexican-Americans versus Caucasians with schizophrenia. In this study, we tested the hypothesis that the lower rate of high EE (hostility and criticism) among Mexican-Americans was the result of cultural factors impacting on how information was reported by the Mexican-American relative of a patient with schizophrenia. We compared the ratings of EE between Caucasian (N = 17) and Mexican-American (N = 44) patients with schizophrenia or schizoaffective disorder and their key relatives using the level of expressed emotion (LEE) scale (paper and pencil instrument rated by the patient and relative separately) and the Five Minute Speech Sample (observational experimenter rated). The ability of the various measures to predict relapse over two years was also examined. Contrary to our hypothesis, there were no differences between patient and family measures within ethnic group. Mexican-American patients and relatives reported lower rates of high EE than Caucasians across all measures. High EE predicted relapse across measures for Caucasian participants, but did not predict relapse for Mexican-Americans on any of the measurement instruments. We discuss the implications of these findings on cross-cultural research and family interventions for individuals with psychotic disorders.

Positive pregnancy outcomes in Mexican immigrants: what can we learn?

Science.gov (United States)

Page, Robin L

2004-01-01

To provide an integrated review of the literature of potential explanations for better than expected pregnancy outcomes in Mexican immigrants, focusing on socioeconomics, social support, desirability of pregnancy, nutrition, substance use, religion, acculturation, and prenatal care. Computerized searches of MEDLINE and CINAHL databases, as well as reference lists from published articles on low birth weight and prematurity in immigrants and acculturation in immigrants from January 1989 to December 2002. Search terms were Mexican immigrant women, childbearing, and pregnancy outcome, and only English-language articles were reviewed. Literature was selected from refereed publications in the areas of nursing, medicine, public health, family, and sociology. Data were extracted using keywords pertinent to pregnancy outcome in Mexican immigrants. Despite having many of the risk factors for poor pregnancy outcomes, Mexican immigrants have superior birth outcomes when compared to U.S.-born women. Social support, familism, healthy diet, limited use of cigarettes and alcohol, and religion may play a role in improved outcomes. The superior outcomes diminish with the process of acculturation as the individual adapts to her new culture. Low birth weight and prematurity are public health concerns in the United States. Through further study of the factors that lead to superior birth outcomes among Mexican immigrant women, rates of low birth weight and prematurity in the United States may be reduced.

MEXICAN DRUG CARTELS AND TERRORIST ORGANIZATIONS, A NEW ALLIANCE

Science.gov (United States)

2016-02-16

Nevertheless, existing studies provide little evidence to support the claim that a risk of collaboration exists between Mexican cartels and...of Defense (DoD) nor Department of Homeland Security (DHS) have a published definition for cartel. For purposes of this study it is important to note...commodities and real estate. According to National Drug Intelligence Center, Mexican and Colombian cartels launder between $18- $39 billion annually.15

Family Structure and Family Processes in Mexican American Families

OpenAIRE

Zeiders, Katharine H.; Roosa, Mark W.; Tein, Jenn-Yun

2011-01-01

Despite increases in single-parent families among Mexican Americans (MA), few studies have examined the association of family structure and family adjustment. Utilizing a diverse sample of 738 Mexican American families (21.7% single parent), the current study examined differences across family structure on early adolescent outcomes, family functioning, and parent-child relationship variables. Results revealed that early adolescents in single parent families reported greater school misconduct,...

Mexican Folkart for Children.

Science.gov (United States)

Dominguez, Graciela; And Others

Directions, suggested materials, and illustrations are given for making paper mache pinatas and masks, cascarones, Ojos de Dios, maracas, dresser scarf embroidery, burlap murals, yarn designs, paper plate trays, paper cut designs, the poppy, sarape aprons, and paper Mexican dolls. Filled with candy and broken, the pinata is used on most Mexican…

Mexican oil industry: Shifting to difficult oil

Energy Technology Data Exchange (ETDEWEB)

Bazan G., Gerardo; Gonzalez, Cristobal J.

2010-09-15

Mexico has stepped into an important transition of declining oil fields and new challenging oil projects. The aim of this paper is to show a new perspective of the oil resources that have been exploited throughout the Mexican territory, as well as the remaining resources yet to be exploited. We have developed a resources/production-costs chart that illustrates the historical and future development of the Mexican oil industry, showing the shift that the industry will face in the coming years; this chart was taken from a model already in use by the most prestige energy agencies in the world.

The Smell of Memories. A Mexican Migrant’s Search for Emotional Sustainability through Mexican Films.

Directory of Open Access Journals (Sweden)

Gabriela Coronado

2011-12-01

Full Text Available For more than 10 years living as a Mexican migrant, between two countries (Mexico and Australia, two cities (Mexico City and Sydney, and two social worlds (Mexican and multicultural Australian ‘families-friends’, I have been immersed in a systematic process of self observation and self reflection on my life in my country of destination. During this time I have explored my memories of place and their relationship with my emotional experiences, looking for strategies to continue to be connected with my country of origin and my people. In this process I discovered films were especially significant in sustaining me emotionally. I benefited from the memory associations triggered by representations of Mexico in films produced by Mexicans or by filmmakers from other nationalities. By reflecting on my responses to those films, in this paper I explore how representations of their country of origin can impact on migrants’ emotional life. Using autoethnography, examining my own subjectivity as a way to arrive at a deeper grasp of these processes, I analyse the roles played by different senses in the process of recollection and in the emotional effects produced, which come to embody the experience. My particular focus in this article is the sense of smell triggered by complex interactions within the sensorium while watching films, producing associations and feelings through which I re-live my memories and maintain my emotional sustainability.

We, You, They? Spanish Traits in the Nationlist Memory of Mexican Architecture

Directory of Open Access Journals (Sweden)

Johanna Lozoya

2010-01-01

Full Text Available The new mestizo tradition in Mexican architectural historiography was invented after the 1930's by sublimating the racist character ever-present in the development of the philosophical, aesthetical, and scientific structures of modern Mexican architectural thought. In the face of the monopoly exerted by the State's cultural ideology on the imaginaries of late-nineteenth-century architectural historiography, still expressed in taxonomies  such as “indian expressionism” or “Creole expressionism”, Spanish traits become at once national and foreign, Mexican and anti- Mexican, traditional and opposed  to tradition modernity and antiquity, universality and locality. This work desconstructs turn-of-the-century arguments  by analyzing the continuity of Hispanic  traits in the post-revolutionary invention of an old mestizo tradition.

The Diffusion of Mexican Immigrants During the 1990s: Explanations and Impacts

OpenAIRE

David Card; Ethan G. Lewis

2005-01-01

Mexican immigrants were historically clustered in a few cities, mainly in California and Texas. During the past 15 years, however, arrivals from Mexico established sizeable immigrant communities in many "new" cities. We explore the causes and consequences of the widening geographic diffusion of Mexican immigrants. A combination of demand-pull and supply push factors explains most of the inter-city variation in inflows of Mexican immigrants over the 1990s, and also illuminates the most importa...

Acculturation and Life Satisfaction Among Immigrant Mexican Adults

Directory of Open Access Journals (Sweden)

Flavio F. Marsiglia

2013-09-01

Full Text Available The numbers of Mexican Americans living in the United States, many of whom are first generation immigrants, are increasing. The process of immigration and acculturation can be accompanied by stress, as an individual attempts to reconcile two potentially competing sets of norms and values and to navigate a new social terrain. However, the outcomes of studies investigating the relationship between levels of acculturation and well-being are mixed. To further investigate the dynamic of acculturation, this article will address the impact of acculturation and familismo, on reported life satisfaction and resilience among Mexican American adults living in the Southwest (N=307, the majority (89% of which are immigrants. The findings indicate that bilingual individuals report significantly higher levels of life satisfaction and resilience than their Spanish-speaking counterparts do. Speaking primarily English only predicted higher levels of resilience but not life satisfaction. Implications for social work practice with Mexican American immigrants are discussed.

Losing American Students, Mexican Universities Struggle against a Scary Image

Science.gov (United States)

Ambrus, Steven

2012-01-01

Like most Mexicans, Eugenio Yarce has been deeply affected by the violence between drug cartels and the Mexican army, which has filled news coverage with accounts of kidnappings, assassinations, and torture. But for Mr. Yarce, deputy rector for outreach here at the private Autonomous Popular University of the State of Puebla, or Upaep, the…

[Observational study of craniofacial growth and development in Mexican children].

Science.gov (United States)

Fijikami, T K; Cedeño Pacheco, E

1991-01-01

The election of a investigation about craniofacial growing and development in Mexican children, was done due to a lack of national information in this rubric and as a fundamental part of the "growing and development in the scholastic" module of the Universidad Autónoma Metropolitana-Xochimilco, which work hypothesis was that "craniofacial growing and development in Mexican, 6 to 12 children in Xochimilco area are due to nutritional deficiency, second dentition eruption delay and dental maloclution "which was totality confirmed in a 100 Mexican facial characteristic children field work study, with cephalometric studies which permit to determine the craniofacial growing standard. This study was corroborated with a 40 children, 4 years later follow up.

Characterization of Mexican zeolite minerals

International Nuclear Information System (INIS)

Jimenez C, M.J.

2005-01-01

50% of the Mexican territory is formed by volcanic sequences of the Pliocene type, which appear extensively in the northwest states (Sonora, Sinaloa, Chihuahua, Durango) and west of Mexico (Jalisco and Nayarit), in central Mexico (Zacatecas, Guanajuato, San Luis Potosi, Queretaro, Hidalgo) and south of Mexico (Guerrero, Oaxaca); therefore, it is to be expected that in our country big locations of natural zeolites exist in its majority of the clinoptilolite type. The present study was focused toward the characterization of two Mexican natural zeolite rocks presumably of the clinoptilolite and filipsite types, one of them comes from the state of Chihuahua and the other of a trader company of non metallic minerals, due that these materials are not characterized, its are not known their properties completely and therefore, the uses that can be given to these materials. In this investigation work it was carried out the characterization of two Mexican zeolite rocks, one coming from the Arroyo zone, municipality of La Haciendita, in the state of Chihuahua; and the other one was bought to a trader company of non metallic minerals. The two zeolites so much in their natural form as conditioned with sodium; they were characterized by means of X-ray diffraction, scanning electron microscopy of high vacuum and elementary microanalysis (EDS), surface area analysis (BET), thermal gravimetric analysis. To differentiate the heulandite crystalline phase of the other clinoptilolite rock, its were carried out thermal treatments. The quantification of Al, Na, Ca, K, Mg, Fe was carried out in solution, by means of atomic absorption spectroscopy and the quantity of Si was determined by gravimetry. The zeolite rocks presented for the major part the crystalline heulandite and clinoptilolite phases for the most part, and it was found that the zeolite coming from the state of Chihuahua possesses a bigger content of heulandite and the denominated filipsite it is really a zeolite

AZTLAN: Mexican platform for analysis and design of nuclear reactors - 15493

International Nuclear Information System (INIS)

Gomez Torres, A.M.; Puente Espel, F.; Valle Gallegos, E. del; Francois, J.L.; Martin-del-Campo, C.; Espinosa-Paredes, G.

2015-01-01

The AZTLAN platform is presented in this paper. This project aims at modernizing, improving and incorporating the neutron transport codes such as AZTLAN, AZKIND and AZNHEX, thermo-hydraulics codes like AZTHECA and thermo-mechanical codes developed in the Mexican institutions of higher education as well as in the Mexican nuclear research institute, in an integrated platform, established and maintained for the benefit of the Mexican nuclear knowledge. An important part of the project is to develop a coupling methodology between neutron transport codes and thermal-hydraulics codes in order to get an accurate 3-dimensional simulation of a reactor core

Acculturation and substance use in a Mexican American college student sample.

Science.gov (United States)

Mercado, Alfonso; Ramirez, Maria; Sharma, Rachita; Popan, Jason; Avalos Latorre, Maria Luisa

2017-01-01

Although the association between acculturation and substance use among Latino groups is important, it is often understudied, especially within specific Latino groups living in geographically distinct communities, such as the Mexican American population in South Texas. The researchers of this study aimed to better understand the effect of acculturation on substance use and alcohol dependence in a Mexican American college student population. This survey study investigated the correlation between acculturation and substance use and dependence by using the Vancouver Index of Acculturation (VIA), items related to substance use (nicotine, marijuana, and cocaine) in a Mexican American college student sample (N = 1,494), and the Short Alcohol Dependence Data Questionnaire (SADD; N = 715). The study was conducted in the Texas-Mexico border region. The results suggest that higher levels of acculturation do not predict increased drug use or alcohol dependence in the Mexican American college students. However, acculturation was found to be associated with lower use of cocaine and marijuana. The discussion examines commonalities and differences in drug use and dependence. Specifically, acculturation seems to have an inverse relationship to substance use and may serve as a protective factor to licit and illicit drug use among Mexican American college students.

Optimal transmission planning under the Mexican new electricity market

International Nuclear Information System (INIS)

Zenón, Eric; Rosellón, Juan

2017-01-01

This paper addresses electricity transmission planning under the new industry and institutional structure of the Mexican electricity market, which has engaged in a deep reform process after decades of a state-owned-vertically-integrated-non-competitive-closed industry. Under this new structure, characterized by a nodal pricing system and an independent system operator (ISO), we analyze welfare-optimal network expansion with two modeling strategies. In a first model, we propose the use of an incentive price-cap mechanism to promote the expansion of Mexican networks. In a second model, we study centrally-planned grid expansion in Mexico by an ISO within a power-flow model. We carry out comparisons of these models which provide us with hints to evaluate the actual transmission planning process proposed by Mexican authorities (PRODESEN). We obtain that the PRODESEN plan appears to be a convergent welfare-optimal planning process. - Highlights: • We model transmission planning (PRODESEN) in the Mexican new electricity market. • We propose a first model with a price-cap mechanism to promote network expansion. • In a second power-flow model, we study centrally-planned grid expansions. • The PRODESEN appears to be a convergent welfare-optimal planning process. • Incentive regulation could further help to implement such an optimal process.

Antibacterial and antifungal activities of some Mexican medicinal plants.

Science.gov (United States)

Ruiz-Bustos, E; Velazquez, C; Garibay-Escobar, A; García, Z; Plascencia-Jatomea, M; Cortez-Rocha, M O; Hernandez-Martínez, J; Robles-Zepeda, R E

2009-12-01

In Mexico about 4,000 plant species have some medicinal use. The aim of this work was to evaluate the antimicrobial activity of six Mexican medicinal plants against fungi and Gram-positive and Gram-negative bacteria. Methanolic extracts were prepared from the Mexican medicinal plants Amphypteringium adstrigens, Castella tortuosa, Coutarea latiflora, Ibervillea sonorae, Jatropha cuneata, and Selaginella lepidophylla. The antibacterial and antifungal activities of the plants were determined by the broth microdilution method and the radial growth inhibition assay, respectively. All Mexican plants tested showed antimicrobial activity. Among the six plant extracts analyzed, J. cuneata showed the highest growth-inhibitory activity against fungi, Gram-positive and Gram-negative bacteria (J. cuneata > A. adstrigens > C. latiflora > C. tortuosa > I. sonorae approximately S. lepidophylla). Shigella flexneri and Staphylococcus aureus were the most susceptible bacteria to plant extracts. Complete inhibition of S. flexneri growth was observed with J. cuneata methanolic extract at 90 microg/mL. This plant extract also showed the strongest antifungal activity against Fusarium verticillioides and Aspergillus niger. Our data suggest that the medicinal plants tested have important antimicrobial properties. This is the first report describing the antimicrobial activities of several of the Mexican medicinal plants used in this study.

Undocumented immigration status and diabetes care among Mexican immigrants in two immigration "sanctuary" areas.

Science.gov (United States)

Iten, A Elizabeth; Jacobs, Elizabeth A; Lahiff, Maureen; Fernández, Alicia

2014-04-01

The objective of this study is to investigate the relationship between immigration status and the patient experience of health care, diabetes self-management, and clinical outcomes among Mexican immigrants with diabetes receiving health care in two immigration sanctuary cities. We used data from the Immigration, Culture and Health Care study, a cross-sectional survey and medical record study of low-income patients with diabetes recruited from public hospitals and community clinics in the San Francisco Bay Area and Chicago. Undocumented Mexican, documented Mexican immigrants, and US-born Mexican-Americans' health care experiences, diabetes self-management, and clinical outcomes were compared using multivariate linear and logistic regressions. We found no significant differences in reports of physician communication, or in measures of diabetes management between undocumented and documented immigrants. All three groups had similar clinical outcomes in glycemic, systolic blood pressure, and lipid control. These results indicate that, at least in some settings, undocumented Mexican immigrants with diabetes can achieve similar clinical outcomes and report similar health care experiences as documented immigrants and US-born Mexican-Americans.

The metabolic syndrome, biomarkers, and the acculturation-health relationship among older Mexican Americans.

Science.gov (United States)

González, Hector M; Tarraf, Wassim; Haan, Mary N

2011-10-01

To examine the acculturation-health relationship using metabolic syndrome biomarkers. Cross-sectional sample data. 1,789 Mexican Americans (60 years and older) from northern California. Biomarkers (waist circumference, blood pressure, fasting plasma glucose, triglycerides, and high-density lipids) were used to construct the metabolic syndrome indicator using American Heart Association criteria. MAIN PREDICTOR: Acculturation Rating Scale for Mexican Americans-II scores. Higher acculturation scores were associated with a significantly lower risk for the metabolic syndrome for foreign-born, but not U.S.-born, Mexican Americans. Immigrant health advantages over U.S.-born Mexican Americans are not evident in older adulthood. Higher acculturation was associated with lowered metabolic syndrome risk among older foreign-born Mexican Americans. This suggests that the prevailing acculturative stress hypothesis may not apply to the health of older adults and that any negative relationship between acculturation and health found in younger adults may yield to different developmental health influences in later adulthood.

Hypertension in Mexican adults: results from the National Health and Nutrition Survey 2006.

Science.gov (United States)

Barquera, Simón; Campos-Nonato, Ismael; Hernández-Barrera, Lucía; Villalpando, Salvador; Rodríguez-Gilabert, César; Durazo-Arvizú, Ramón; Aguilar-Salinas, Carlos A

2010-01-01

To describe the prevalence of hypertension among Mexican adults, and to compare to that observed among Mexican-Americans living in the US. The primary data source came from adults (>20 years) sampled (n=33366) in the Mexican National Health and Nutrition Survey 2006 (ENSANUT 2006). Hypertension was defined when systolic blood pressure was >or=140 and/or diastolic was >or= 90 or patients previously diagnosed. A total of 43.2% of participants were classified as having hypertension. We found a positive statistically significant association (p<0.05) between hypertension and BMI, abdominal obesity, previous diagnosis of diabetes and hypercholesterolemia. Subjects with hypertension had a significantly higher odd of having a history of diabetes or hypercholesterolemia. Hypertension had a higher prevalence in Mexico than among Mexican-Americans living in the US. Hypertension is one of the most prevalent chronic diseases in Mexico. In the last six years in Mexico, a substantial increase (25%) has been observed in contrast to the reduction seen among Mexican-Americans (-15%).

Participants in urban Mexican male homosexual encounters.

Science.gov (United States)

Carrier, J M

1971-12-01

Preliminary data are presented on 53 urban Mexican males interviewed during 1970-1971 in a study of homosexual encounters in a large Mexican city. These data are compared with data from recent studies in the United States and England of male homosexual behavior. Although preliminary and limited, the Mexican data indicate that cultural factors are important determinants of life styles and sex practices of homosexual males. Forty-eight of the 53 (90%) preferred and usually practiced anal intercourse, four preferred oral contacts, and one preferred mutual masturbation. Interviewees were also grouped according to major type of sex activity during the first sustained year of homosexual activity after puberty. One intragroup comparison indicates significant differences between anal active and anal passive interviewees. For example, as children anal passive subjects had significantly more homosexual contacts with adults; they also considered themselves more effeminate and as children were more involved with female sex-typed activities. Comparison of data from the English and United States studies with the present data suggests that preference for a particular sexual technique is not as developed in the former two countries; when there is a preference, it is not usually for anal intercourse.

Genetic analysis of Mexican Criollo cattle populations.

Science.gov (United States)

Ulloa-Arvizu, R; Gayosso-Vázquez, A; Ramos-Kuri, M; Estrada, F J; Montaño, M; Alonso, R A

2008-10-01

The objective of this study was to evaluate the genetic structure of Mexican Criollo cattle populations using microsatellite genetic markers. DNA samples were collected from 168 animals from four Mexican Criollo cattle populations, geographically isolated in remote areas of Sierra Madre Occidental (West Highlands). Also were included samples from two breeds with Iberian origin: the fighting bull (n = 24) and the milking central American Criollo (n = 24) and one Asiatic breed: Guzerat (n = 32). Genetic analysis consisted of the estimation of the genetic diversity in each population by the allele number and the average expected heterozygosity found in nine microsatellite loci. Furthermore, genetic relationships among the populations were defined by their genetic distances. Our data shows that Mexican cattle populations have a relatively high level of genetic diversity based either on the mean number of alleles (10.2-13.6) and on the expected heterozygosity (0.71-0.85). The degree of observed homozygosity within the Criollo populations was remarkable and probably caused by inbreeding (reduced effective population size) possibly due to reproductive structure within populations. Our data shows that considerable genetic differentiation has been occurred among the Criollo cattle populations in different regions of Mexico.

Conflict Resolution in Mexican-Origin Couples: Culture, Gender, and Marital Quality

Science.gov (United States)

Wheeler, Lorey A.; Updegraff, Kimberly A.; Thayer, Shawna M.

2010-01-01

This study examined associations between Mexican-origin spouses' conflict resolution strategies (i.e., nonconfrontation, solution orientation, and control) and (a) gender-typed qualities and attitudes, (b) cultural orientations, and (c) marital quality in a sample of 227 couples. Results of multilevel modeling revealed that Mexican cultural…

Mexican and Cuban Composers in New York City circa 1880-1920

Directory of Open Access Journals (Sweden)

John Koegel

2006-10-01

Full Text Available Cuban musicians active in New  York in the 1860s through the 1890s such as Ignacio Cervantes, Emilio Agramonte, and Rosalia Chalia assisted in the struggle for Cuban independence from Spain from the vantage point of New York's Cuban émigré community, and they also established  a strong  presence in the city's musical life.  Important Mexican musicians such as Miguel Lerdo  de Tejada and Carlos Curti intermittently visited New York or were long-term residents there. This was especially true during the late- nineteenth century, when the forced political stability during the Porfiriato made possible the extended visits of Mexican musicians and ensembles to North American cities such as New York. The Mexican Revolution also sent Mexican musicians to the United States in search of political freedom as well as economic and artistic opportunities that were temporarily closed to them in Mexico.

Nervios and dysphoria in Mexican American widows.

Science.gov (United States)

Kay, M; Portillo, C

1989-01-01

One hundred widows participating in experimental research entitled Efficacy of Support Groups for Mexican American Widows were studied to learn how they express the loss of their husbands. Mourning practices, acknowledged symptoms of dysphoria, and somatic reactions were studied to learn if the syndrome of nervios subsumes their reaction to bereavement. In addition, their responses to instruments designed to measure depression, the Spanish version of the Beck Depression Inventory and the Center for Epidemiologic Studies Depression Scale, were examined for correlation with nervios and relationships to Mexican American acculturation. Nervios seems to be a manifestation of dysphoria rather than a specific syndrome for these women.

The Food Environment in an Urban Mexican American Community

OpenAIRE

Lisabeth, Lynda D; Sánchez, Brisa N; Escobar, James; Hughes, Rebecca; Meurer, William J; Zuniga, Belinda; Garcia, Nelda; Brown, Devin L; Morgenstern, Lewis B

2010-01-01

The objective was to determine whether ethnic composition of neighborhoods is associated with number and type of food stores in an urban, Mexican American US community. Data were from a commercial food store data source and the US Census. Multivariate count models were used to test associations with adjustment for neighborhood demographics, income, and commercialization. Neighborhoods at the 75th percentile of percent Mexican American (76%) had nearly four times the number of convenience stor...

The United Mexican States: an update.

Science.gov (United States)

Hakkert, R; Aguirre, E J

1988-09-01

Although the popular North American opinion of Mexico is one that paints a picture of a poor, disadvantaged country, South America sees Mexico has a richer more prosperous nation. It is observed that only in the Latin American countries of Venezuela, Suriname and Trinidad and Tobago do consumers have higher incomes than Mexican consumers. Moreover, while millions of Mexicans migrate to the United States to seek a better standard of living, several thousand Central American refugees illegally migrate to Mexico in search of a better life. This better life includes an increased age of lie expectancy from 51 years in the 1950s to 64 years in the late 1970s. There have also been improvements in health care and school enrollments and in the low cost availability of education. Tourism and the prospect of the manufacturing of energy are significant, positive factors working in favor of an improved Mexican economy and a higher overall quality of life. However, Mexico faces serious problems such as a mounting foreign debt. Also rising is Mexico's population which has doubled since 1964 and which continues to grow at a rate of 1.9%. Economic programs and reforms and family development planning have been instituted in response to the countries' current recession and population growth and have begun to show positive results.

Mexican and Mexican-American children's funds of knowledge as interventions into deficit thinking: opportunities for praxis in science education

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Licona, Miguel M.

2013-12-01

In this case study, I use an ethnographic-style approach to understand the funds of knowledge of immigrant families living in colonias on both sides of the US/Mexico border. I focus on how these "knowledges" and concomitant experiences impact the ways we perceive and treat immigrant students who have all too often been viewed through deficit lenses that relegate them to the lowest expectations and outcomes in the classroom. I find that Mexican and Mexican-American families hold unusually sophisticated and relevant "knowledges" to mitigate their everyday lives. In this paper, I will refer to citizens of Mexico, whether they reside in Mexico or have crossed to the United States legally or without documentation for purposes of work, as Mexican. People who have crossed the border and are living in the US as legal residents or have gained citizenship are referred to as Mexican-Americans. They live a hybrid identity that is varied and dynamic, an issue that adds to the complexity of the content and contexts of this study. These families know and use these "knowledges" on a daily basis, yet they are not recognized by teachers in the US as a starting point to affirm and support immigrant children. Instead, immigrant children are relegated to the non-gifted and lower track classes where science is taught from an abstract and non-contextual and therefore less engaged basis. The approach I outline here, based on insights from my case study, can greatly improve teachers' abilities to prepare their curricula for diversity in science education and science literacy as well as for broad expectations for student success.

Changes in health selection of obesity among Mexican immigrants: a binational examination.

Science.gov (United States)

Ro, Annie; Fleischer, Nancy

2014-12-01

Health selection is often measured by comparing the health of more recent immigrants to the native born of their new host country. However, this comparison fails to take into account two important factors: (1) that changes in the health profile of sending countries may impact the health of immigrants over time, and (2) that the best comparison group for health selection would be people who remain in the country of origin. Obesity represents an important health outcome that may be best understood by taking into account these two factors. Using nationally-representative datasets from Mexico and the US, we examined differences in obesity-related health selection, by gender, in 2000 and 2012. We calculated prevalence ratios from log-binomial models to compare the risk of obesity among recent immigrants to the US to Mexican nationals with varying likelihood of migration, in order to determine changes in health selection over time. Among men in 2000, we found little difference in obesity status between recent immigrants to the US and Mexican non-migrants. However, in 2012, Mexican men who were the least likely to migrate had higher obesity prevalence than recent immigrants, which may reflect emerging health selection. The trends for women, however, indicated differences in obesity status between recent Mexican immigrants and non-migrants at both time points. In both 2000 and 2012, Mexican national women had significantly higher obesity prevalence than recent immigrant women, with the biggest difference between recent immigrants and Mexican women who were least likely to migrate. There was also indication that selection increased with time for women, as the differences between Mexican nationals and recent immigrants to the US grew from 2000 to 2012. Our study is among the first to use a binational dataset to examine the impact of health selectivity, over time, on obesity. Copyright © 2014 Elsevier Ltd. All rights reserved.

4. Mexican School of Nuclear Physics

International Nuclear Information System (INIS)

Aguilera, E.F.; Hernandez, E.; Hirsch, J.G. -mail: svp@nuclear.inin.mx

2005-01-01

The IV Mexican School of Nuclear Physics, organized by the Nuclear Physics Division of the Mexican Physics Society, taken place from June 27 to July 8, 2005 in the Institute of Nuclear Sciences and the Institute of Physics of the UNAM and in the National Institute of Nuclear Research (ININ). This school, as the previous ones, it was guided to the students of the last semesters of the career of Physics, of the Post grade of the same specialty, and of other adjacent careers. To give the students a current vision of some of the topics more important of the nuclear physics and their relationship with other near areas of the physics it was the objective of this School. The School covered a wide range of theoretical and experimental courses, imparted in its majority by Mexican expert professor-investigators in the subject to whom we thank them the one effort and the quality of their presentations, reflected in the content of this document. The answer of the students to the convocation was excellent, 31 students presented application for admission coming from the following institutions: Meritorious Autonomous University of Puebla, National Institute of Nuclear Research, Technological Institute of Orizaba, National Polytechnic Institute, The University of Texas at Brownsville, Autonomous University of the State de Mexico, Autonomous University of the State of Morelos, Autonomous University of Baja California, Autonomous University of San Luis Potosi, University of Guadalajara, University of Guanajuato, National Autonomous University of Mexico, University of Texas, at El Paso and University Veracruzana. They were admitted to those 22 students with the higher averages qualifications of the list of applicants. The organizers of this school thank the financial support granted by the following sponsor institutions: Institute of Nuclear Sciences, UNAM, Institute of Physics, UNAM, Coordination of the Scientific Research, UNAM, National Institute of Nuclear Research, Nuclear

Survey Response Styles, Acculturation, and Culture Among a Sample of Mexican American Adults.

Science.gov (United States)

Davis, Rachel E; Resnicow, Ken; Couper, Mick P

2011-10-01

A number of studies have investigated use of extreme (ERS) and acquiescent (ARS) response styles across cultural groups. However, due to within-group heterogeneity, it is important to also examine use of response styles, acculturation, and endorsement of cultural variables at the individual level. This study explores relationships between acculturation, six Mexican cultural factors, ERS, and ARS among a sample of 288 Mexican American telephone survey respondents. Three aspects of acculturation were assessed: Spanish use, the importance of preserving Mexican culture, and interaction with Mexican Americans versus Anglos. These variables were hypothesized to positively associate with ERS and ARS. Participants with higher Spanish use did utilize more ERS and ARS; however, value for preserving Mexican culture and interaction with Mexican Americans were not associated with response style use. In analyses of cultural factors, endorsement of familismo and simpatia were related to more frequent ERS and ARS, machismo was associated with lower ERS among men, and la mujer was related to higher ERS among women. Caballerismo was marginally associated with utilization of ERS among men. No association was found between la mujer abnegada and ERS among women. Relationships between male gender roles and ARS were nonsignificant. Relationships between female gender roles and ARS were mixed but trended in the positive direction. Overall, these findings suggest that Mexican American respondents vary in their use of response styles by acculturation and cultural factors. This usage may be specifically influenced by participants' valuing of and engagement with constructs directly associated with social behavior.

Acculturative stress negatively impacts maternal depressive symptoms in Mexican-American women during pregnancy

Science.gov (United States)

D’Anna-Hernandez, Kimberly L.; Aleman, Brenda; Flores, Ana-Mercedes

2015-01-01

Background Mexican-American women exhibit high rates of prenatal maternal depressive symptoms relative to the general population. Though pregnant acculturated Mexican-American women experience cultural stressors such as acculturation, acculturative stress and discrimination that may contribute to elevated depressive symptoms, the contribution of these socio-cultural correlates to depressive symptomology is unknown. Method Ninety-eight pregnant women of Mexican descent were recruited from a community hospital clinic during their first trimester. Women completed surveys about acculturation, acculturative stress, perceived discrimination, general perceived stress, and maternal depressive symptoms as well as the potential protective factor of Mexican cultural values. Results Women who experienced greater acculturative and perceived stress, but not perceived discrimination or acculturation, reported significantly elevated depressive symptoms during pregnancy. Also, women who experienced greater acculturative stress identified with a mixture of Mexican and American cultural values. However, only the Mexican cultural value of respect was protective against maternal depressive symptoms while adhering to the Anglo value of independence and self-reliance was a risk factor. Limitations A limitation in the study is the cross-sectional and descriptive self-report nature of the work, underscoring the need for additional research. Moreover, physiological measures of stress were not analyzed in the current study. Conclusions Results point to acculturative stress, above other cultural stressors, as a potential intervention target in culturally competent obstetric care. These findings have implications for maternal mental health treatment during pregnancy, which likely affects maternal-fetal programming and may favorably affect perinatal outcomes in the vulnerable Mexican-American population. PMID:25699668

The Relation between Maternal and Child Depression in Mexican American Families

Science.gov (United States)

Corona, Marissa; McCarty, Carolyn; Cauce, Ana Mari; Robins, Richard W.; Widaman, Keith F.; Conger, Rand D.

2012-01-01

In an effort to better understand possible pathways that lead to a relatively high incidence of depressive symptoms among Mexican American youth, an interpersonal stress model of depression was tested using a community sample of 674 Mexican American mothers and their 5th grade children. Structural equation analyses revealed that maternal…

An Anthropology of "Familismo": On Narratives and Description of Mexican/Immigrants

Science.gov (United States)

Smith-Morris, Carolyn; Morales-Campos, Daisy; Alvarez, Edith Alejandra Castaneda; Turner, Matthew

2013-01-01

Research on core cultural values has been central to behavioral and clinical research in ethnic groups. "Familismo" is one such construct, theorized as the strong identification and attachment of Hispanic persons with their nuclear and extended families. Our anthropological research on this concept among Mexicans and Mexican immigrants in the…

The Politics of Drug Trafficking in Mexican and Mexico-Related Narconovelas

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Palaversich, Diana

2006-01-01

This essay traces the emergence of the Mexican and Mexico-related narconovela. It examines perspectives on drug trafficking and traffickers expressed in novels by Elmer Mendoza, Leonides Alfaro, Gerardo Cornejo, Homero Aridjis, Arturo Perez-Reverte, and Paul Flores. The variety of positions taken refutes the tendency of the Mexican mainstream…

Predictors of Mexican American Mothers' and Fathers' Attitudes toward Gender Equality.

Science.gov (United States)

Leaper, Campbell; Valin, Dena

1996-01-01

Among 50 Mexican American married mothers and 33 Mexican American married fathers of preschool children, egalitarian gender attitudes were related to greater educational attainment and placing lower value on competitiveness for both mothers and fathers, and to U.S. birth and holding communal values for mothers. Suggests that egalitarian gender…

Glucose transporter distribution in the vessels of the central nervous system of the axolotl Ambystoma mexicanum (Urodela: Ambystomatidae).

Science.gov (United States)

Lazzari, Maurizio; Bettini, Simone; Ciani, Franco; Franceschini, Valeria

2008-10-01

The GLUT-1 isoform of the glucose transporter is commonly considered a reliable molecular marker of blood-brain barrier endothelia in the neural vasculature organized in a three-dimensional network of single vessels. The central nervous system of the axolotl Ambystoma mexicanum is characterized by a vascular architecture that contains both single and paired vessels. The presence and distribution of the GLUT-1 transporter are studied in this urodele using both immunoperoxidase histochemistry and immunogold technique. Light microscopy reveals immunopositivity in both parenchymal and meningeal vessels. The transverse-sectioned pairs of vessels do not show the same size. Furthermore, in the same pair, the two elements often differ in diameter. The main regions of the central nervous system show a different percentage of the paired structures. Only immunogold cytochemistry reveals different staining intensity in the two adjoined elements of a vascular pair. Colloidal gold particles show an asymmetric distribution in the endothelia of both single and paired vessels. These particles are more numerous on the abluminal surface than on the luminal one. The particle density is calculated in both vascular types. The different values could indicate functional differences between single and paired vessels and between the two adjoined elements of a pair, regarding glucose transport.

Obesity and central adiposity in Mexican adults: results from the Mexican National Health and Nutrition Survey 2006 Obesidad y adiposidad central en adultos mexicanos: resultados de la Encuesta Nacional de Salud y Nutrición 2006

OpenAIRE

Simón Barquera; Ismael Campos-Nonato; Lucía Hernández-Barrera; Mario Flores; Ramón Durazo-Arvizu; Rebecca Kanter; Juan A Rivera

2009-01-01

OBJECTIVE: To estimate the prevalence of overweight, obesity and central adiposity in Mexico, and to explore trends compared to the previous Mexican National Health Survey (ENSA 2000) and to Mexican-Americans. MATERIAL AND METHODS: The Mexican National Health and Nutrition Survey 2006 (ENSANUT 2006) was used to describe overweight, obesity and central adiposity. Trends over time were assessed using the ENSA 2000 and by comparing the ENSANUT 2006 results to those of Mexican-Americans using the...

Do health care needs of indigent Mexican-American, black, and white adolescents differ?

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Fitzpatrick, S B; Fujii, C; Shragg, G P; Rice, L; Morgan, M; Felice, M E

1990-03-01

Few studies have addressed the specific health care needs of Mexican-American adolescents. This 2-year study assessed the routine health care needs and incidence of chronic illness among 279 Mexican-American, 233 white, and 333 black indigent adolescents enrolled in a vocational training program. Mexican-Americans were more likely to have a positive purified protein derivative tuberculin test and acne/eczema requiring treatment. Blacks were more likely to have incomplete immunizations and thyroid disorders, while whites were more likely to have musculoskeletal conditions and require family planning services and psychiatric intervention for mental health disorders. Although no difference in incidence of chronic illness was noted, our data suggests that routine health care needs may differ among indigent Mexican-American, white, and black adolescents.

Espanol mexicano y espanol chicano: Problemas y propuestas fundamentales (Mexican Spanish and Chicano Spanish: Fundamental Problems and Proposals).

Science.gov (United States)

Hidalgo, Margarita

1987-01-01

Discusses the rise of Mexican Spanish as a distinct variety of Spanish and describes the regional and social dialects of contemporary Mexican Spanish. Although countless similarities exist between Mexican Spanish and the Chicano Spanish spoken in the southwestern United States, Mexican Spanish shows greater variability. (GR)

[Peredo's Inferno: a Mexican physician-translator in the XIX century].

Science.gov (United States)

Delgado García, Guillermo; Estañol Vidal, Bruno

2013-01-01

Manuel Peredo (1830-1890) participated fully in Mexico's national literary circles during the second half of the 19th century. Besides being recognized for his translation of Basch's Memories of Mexico, Peredo also translated the first tercets of Inferno's Canto XXXIII. Although forgotten today, his contribution is significant since it is the second Mexican translation of Dante, and particularly, the first Mexican translation of Canto XXXIII.

Migration, Culture and Health of Mexican Americans in an Acculturation Gradient.

Science.gov (United States)

Aranda, Robert G.; Acosta, Phyllis B.

In East Los Angeles, 26 Mexican American families with children in Head Start responded to a questionnaire gathering data on birthplace, family income, occupation, individuals in the home, dietary intake and habits of the children, food buying and preparation practices, and pregnancy history of the mothers. In San Ysidro, 101 Mexican American…

Maternal Beliefs and Parenting Practices Regarding Their Preschool Child's Television Viewing: An Exploration in a Sample of Low-Income Mexican-Origin Mothers.

Science.gov (United States)

Thompson, Darcy A; Polk, Sarah; Cheah, Charissa S L; Vandewater, Elizabeth A; Johnson, Susan L; Chrismer, Marilyn Camacho; Tschann, Jeanne M

2015-08-01

To explore maternal beliefs about television (TV) viewing and related parenting practices in low-income Mexican-origin mothers of preschoolers. Semistructured interviews were conducted with 21 low-income Mexican-origin mothers of preschoolers. Interviews were audio recorded and analyzed using a theoretically based thematic analytic approach. Mothers described strong beliefs about the positive and negative impact of TV content. Mothers emphasized the educational value of specific programming. Content restrictions were common. Time restrictions were not clearly defined; however, many mothers preferred short versus long episodes of viewing. Mothers spoke positively about family viewing and the role of TV viewing in enabling mothers to accomplish household tasks. These findings have implications for intervening in this population. Interventionists should consider the value mothers place on the educational role of TV viewing, the direct benefit to mothers of viewing time, the lack of clear time limits, and the common practice of family co-viewing. © The Author(s) 2015.

The Free Trade Agreement and the Mexican health sector.

Science.gov (United States)

Laurell, A C; Ortega, M E

1992-01-01

This article presents a discussion of the probable implications for the Mexican health sector of the Free Trade Agreement (FTA) between the United States, Canada, and Mexico. The authors argue that the FTA should be seen as part of neoliberal policies adopted by the Mexican government in 1983 that are based on large-scale privatization and deregulation of labor relations. In this general context the health sector, which traditionally has been dominated by public institutions, is undergoing a deep restructuring. The main trends are the decapitalization of the public sector and a selective process of privatization that tends to constitute the private health sector in a field of capital accumulation. The FTA is likely to force a change in Mexican health legislation, which includes health services in the public social security system and recognizes the right to health, and to accelerate selective privatization. The U.S. insurance industry and hospital corporations are interested in promoting these changes in order to gain access to the Mexican market, estimated at 20 to 25 million persons. This would lead to further deterioration of the public institutions, increasing inequalities in health and strengthening the private sector. The historical trend toward the integration of a National Health Service in Mexico would be interrupted in favor of formation of a dual private-public system.

Periodontitis associated with chronic kidney disease among Mexican Americans.

Science.gov (United States)

Ioannidou, Effie; Hall, Yoshio; Swede, Helen; Himmelfarb, Jonathan

2013-01-01

In comparison to non-Hispanic whites, a number of health-care disparities, including poor oral health, have been identified among Hispanics in general and Mexican Americans in particular. We hypothesized that Mexican Americans with chronic kidney disease (CKD) would have higher prevalence of chronic periodontitis compared with Mexican Americans with normal kidney function, and that the level of kidney function would be inversely related to the prevalence of periodontal disease. We examined this hypothesis using the National Health and Nutrition Examination Survey 1988-1994 (NHANES III) data set. We followed the American Academy of Periodontology/Center for Disease Control and Prevention case definition for periodontitis. Glomerular filtration rate was estimated using the CKD-Epidemiology equation for Hispanic populations. The classification to CKD stages was based on the National Kidney Foundation Kidney Disease Outcomes Quality Initiative. Periodontitis prevalence increased across the kidney function groups showing a statistically significant dose-response association (Pperiodontitis compared with Mexican Americans with normal kidney function after adjusting for potential confounders such as smoking, diabetes, and socioeconomic status. Multivariate adjusted odds ratio for periodontitis significantly increased with 1, 5, and 10 mL/minute estimated glomerular filtration rate reduction from the mean. This is the first report, to the best our knowledge, that showed an increase of periodontitis prevalence with decreased kidney function in this population. © 2012 American Association of Public Health Dentistry.

The Binational Civic and Political Engagement of Mexican Migrant Hometown Associations and Federations in the United States

Directory of Open Access Journals (Sweden)

Xóchitl Bada

2014-06-01

Full Text Available This article focuses on the history and current situation of Mexican hometown associations (HTAs in the United States with a special emphasis on Chicago-based Mexican hometown associations and federations. It presents empirical evidence of new forms of binational engagement among Mexican migrant communities in the United States leading to the creation of a Mexican migrant civil society.

Employers mexican migrants in the United States

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Eduardo Fernández Guzmán

2013-09-01

Full Text Available You might think that by definition the migrant labor plays in less profitable niches and meager social mobility. However, a large group of migrants in different economically developed countries have successfully launched businesses of diverse nature and volume. This is why entrepreneurship of migrants is an issue that has received increasing attention in recent years. Compared to other immigrant groups in the United States, Mexicans show low levels of entrepreneurial activity. The aim of this paper is to, through a general literature review of official statistical data, a preliminary analysis of mexican migrant entrepreneurship in the United States, that is to say in recent years has been growing in importance.

Mexican renewable electricity law

Energy Technology Data Exchange (ETDEWEB)

Ruiz-Mendoza, B.J.; Sheinbaum-Pardo, C. [Institute of Engineering of the National Autonomous University of Mexico, Circuito Exterior s/n, Edificio 12 Bernardo Quintana, Piso 3, Cubiculo 319, Ciudad Universitaria, Delegacion Coyoacan, CP 04510, Mexico D.F. (Mexico)

2010-03-15

Two renewable electricity bills have been proposed in Congress since 2005 in Mexico. The first one was rejected by the Senate and the second one was approved by both the House of Representatives and the Senate in October 2008. Our objective is to explain the nature of both bills and to analyze each of them bearing in mind the Mexican electricity sector management scheme. In the Mexican electricity sector single-buyer scheme, the state-owned companies (Comision Federal de Electricidad and Luz y Fuerza del Centro) are responsible of the public services and the private sector generates electricity under six modalities: self-supply, cogeneration, independent production, small production, export, and import, which are not considered a public service. This scheme has caused controversies related to the constitutionality of the 1992 Power Public Services Law that allowed this scheme to be implemented. Both bills, the rejected one and the approved one, were formulated and based on that controversial law and their objectives are linked precisely more to the controversial issues than to the promotion of renewable electricity technologies; consequently, the gap among environmental, economic and social issues related with sustainability notion is wider. (author)

Mexican renewable electricity law

International Nuclear Information System (INIS)

Ruiz-Mendoza, B.J.; Sheinbaum-Pardo, C.

2010-01-01

Two renewable electricity bills have been proposed in Congress since 2005 in Mexico. The first one was rejected by the Senate and the second one was approved by both the House of Representatives and the Senate in October 2008. Our objective is to explain the nature of both bills and to analyze each of them bearing in mind the Mexican electricity sector management scheme. In the Mexican electricity sector single-buyer scheme, the state-owned companies (Comision Federal de Electricidad and Luz y Fuerza del Centro) are responsible of the public services and the private sector generates electricity under six modalities: self-supply, cogeneration, independent production, small production, export, and import, which are not considered a public service. This scheme has caused controversies related to the constitutionality of the 1992 Power Public Services Law that allowed this scheme to be implemented. Both bills, the rejected one and the approved one, were formulated and based on that controversial law and their objectives are linked precisely more to the controversial issues than to the promotion of renewable electricity technologies; consequently, the gap among environmental, economic and social issues related with sustainability notion is wider. (author)

Men of Mexican Origin Who Abuse Women: A Qualitative Study.

Science.gov (United States)

Montalvo-Liendo, Nora; Matthews, Debra W; Gilroy, Heidi; Nava, Angeles; Gangialla, Christyn

2018-03-01

Current literature indicates that intimate partner violence is a complex phenomenon that exists worldwide. However, little is known about why some men of Mexican origin abuse women. This descriptive study was conducted to understand the experiences of men of Mexican origin who abuse their intimate partners. A qualitative research design was used to conduct this study in a south Texas border community adjacent to the United States-Mexico border. This study builds on existing research and furthers the knowledge related to the factors contributing to intimate partner violence, including cultural factors. The results also reinforce the negative impacts of intimate partner violence on children and the family structure. Further research is needed to support the development of a culturally appropriate prevention and intervention program for men of Mexican origin who abuse women and their families.

Training in the Mexican company: a study of job training

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Alma Lilia Sapién Aguilar

2014-12-01

Full Text Available The processes of training and instruction in a medium-sized Mexican company are not being understood as an investment that contributes to business success.The aim of this study was to analyze these processes. The methodological approach was exploratory and descriptive with a non-experimental or ex post facto design. The Mexican Business Information System was consulted and 17 medium-sized companies in the industrial sector were randomly chosen. The results indicated that in the median Mexican company decisive actions must be taken in order to achieve that training and instruction are no longer seen as an unnecessary expense. They need to be understood as the best investment one can make in human resources. Therefore, training and instruction must become a part of the work culture of any organization.

Durational and generational differences in Mexican immigrant obesity: Is acculturation the explanation?

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Creighton, Mathew J.; Goldman, Noreen; Pebley, Anne R.; Chung, Chang Y.

2012-01-01

Using the Los Angeles Family and Neighborhood Survey (L.A.FANS-2; n = 1610), we explore the link between Mexican immigrant acculturation, diet, exercise and obesity. We distinguish Mexican immigrants and 2nd generation Mexicans from 3rd+ generation whites, blacks and Mexicans. First, we examine variation in social and linguistic measures by race/ethnicity, duration of residence and immigrant generation. Second, we consider the association between acculturation, diet and exercise. Third, we evaluate the degree to which acculturation, diet, exercise, and socioeconomic status explain the association between race/ethnicity, immigrant exposure to the US (duration since immigration/generation), and adult obesity. Among immigrants, we find a clear relationship between acculturation measures, exposure to the US, and obesity-related behaviors (diet and exercise). However, the acculturation measures do not clearly account for the link between adult obesity, immigrant duration and generation, and race/ethnicity. PMID:22575698

Sanitary and Phytosanitary Measures: The Case of Mexican Avocados

OpenAIRE

Bakshi, Nishita

2003-01-01

This thesis examines the effects on demand, supply, imports, and prices of partial easing of sanitary and phytosanitary (SPS) barriers to trade in the U.S. market in the case of Mexican avocados. The SPS Agreement plays a role in the avocado market studied here through its implications for negotiations between countries that have not utilized the formal channels of the WTO for resolving disputes. A quarantine in place from 1914 until very recently banned entry of Mexican avocados into the...

Para Los Ninos -- For the Children: Improving Education for Mexican Americans.

Science.gov (United States)

Sotomayor, Frank

The U.S. Commission on Civil Rights conducted the Mexican American Education Study between 1969 and 1974. Drawn from the published and unpublished findings of this study, this report discusses the education of Mexican Americans in the 5 Southwestern states of Arizona, California, Colorado, New Mexico, and Texas, where about 85 percent of all…

Social and cultural influences among Mexican border entrepreneurs.

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Díaz Bretones, Francisco; Cappello, Héctor M; Garcia, Pedro A

2009-06-01

Social and cultural conditions (including U.S. border and inland influence, role models within the family, and educational background) which affect locus of control and achievement motivation among Mexican entrepreneurs were explored among 64 selected entrepreneurs in two Mexican towns, one on the Mexico-U.S. border, the other located inland. Analyses showed that the border subsample scored higher on External locus of control; however, in both subsamples the father was an important element in the locus of control variable and the entrepreneur status. No statistically significant mean difference was noted for achievement motivation. Practical applications and limitations are discussed.

Proverbs in Mexican American Tradition.

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Arora, Shirley L.

1982-01-01

Examines proverb use among 304 Mexican Americans (aged 16-85) of Los Angeles (California), assembling information on how or where particular proverbs were learned, with whom or what kind of individual their use is associated, the occasions on which they are used, and general attitudes toward the use of proverbs. (LC)

Father involvement in Mexican origin families: Preliminary development of culturally-informed measure

Science.gov (United States)

Roubinov, Danielle S.; Luecken, Linda J.; Gonzales, Nancy A.; Crnic, Keith A.

2015-01-01

Objectives An increasing body of research has documented the significant influence of father involvement on children’s development and overall well-being. However, extant research has predominately focused on middle-class Caucasian samples with little examination of fathering in ethnic minority and low-income families, particularly during the infancy period. The present study evaluated measures of early father involvement (paternal engagement, accessibility, and responsibility) that were adapted to capture important cultural values relevant to the paternal role in Mexican origin families. Methods A sample of 180 Mexican origin mothers (M age = 28.3) and 83 Mexican origin fathers (M age = 31.5) were interviewed during the perinatal period. Results Descriptive analyses indicated that Mexican origin fathers are involved in meaningful levels of direct interaction with their infant. A two-factor model of paternal responsibility was supported by factor analyses, consisting of a behavioral responsibility factor aligned with previous literature and culturally-derived positive machismo factor. Qualities of the romantic relationship, cultural orientation, and maternal employment status were related to indices of father involvement. Conclusions These preliminary results contribute to understanding of the transition to fatherhood among low-income Mexican origin men and bring attention to the demographic, social, and cultural contexts in which varying levels of father involvement may emerge. PMID:26237543

PEMEX: The Mexican state petroleum agency

International Nuclear Information System (INIS)

1993-03-01

An overview is presented of the Mexican state petroleum company PEMEX. The Mexican government created PEMEX through the expropriation of the largely foreign-dominated industry. Mexico is the world's fifth largest crude oil producer, and in 1992 PEMEX had proven reserves of 65.5 billion bbl, crude production of 2.668 million bbl/d, gas production of 3.6 billion cubic feet per day, refined product production of 1.57 million bbl/d and 18 million tonnes of petrochemical production per year. A background is presented of Mexico's economy, followed by discussion of PEMEX's market, the best sales prospects for foreign suppliers, a company profile, financial structure, exploration and production, refining, gas and basic petrochemicals, petrochemicals, transportation and distribution, research and development, recent activities, planned future activities, procurement, and market access. Extensive appendices supply relevant contacts and information. 30 tabs

Mexican participation in the AMS project

Science.gov (United States)

Menchaca-Rocha, A.; Buenerd, M.; Cabrera, J. I.; Canizal, C.; Esquivel, O.; Núñez, R.; Plascencia, J. C.; Reyes, T.; Villoro, M. F.

2001-05-01

Optical characterization of hydrophobic silica aerogel SP-25 for the RICH, and a scheme to generate particle-ID conditions on TOF and Tracker amplitude data are reported, as part of a Mexican effort to contribute to the AMS Project. .

Mammagraphy Use by Older Mexican American Women

National Research Council Canada - National Science Library

Freeman, Jean

1998-01-01

The purpose of this study is to examine the determinants of mammographic screening in older Mexican- American women, particularly the influence of strong family relationships on promoting screening behavior...

Dietary quality and household food insecurity among Mexican children and adolescents.

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Rodríguez, Luis A; Mundo-Rosas, Verónica; Méndez-Gómez-Humarán, Ignacio; Pérez-Escamilla, Rafael; Shamah-Levy, Teresa

2017-10-01

Seventy percent of Mexican households experience some level of food insecurity (FI). Studies have shown positive associations between FI and poor dietary quality. As far as it is known, this is the first time the Healthy Eating Index (HEI-2010) has been used to assess dietary quality of children and adolescents in Mexico, and to examine if FI is related to it. The objective of this research is to assess dietary quality and its association with FI among Mexican children and adolescents from a nationally representative cross-sectional sample. We analyzed data from 4635 2-19-year-old Mexican children and adolescents participating in the Mexican National Health and Nutrition Survey (Ensanut 2012). FI was measured using the Latin American and Caribbean Household Food Security Scale (ELCSA) and dietary quality with the HEI-2010. We examined the association between FI and dietary quality using multivariate linear regressions. Dietary quality was worst as FI became more severe among children and adolescents compared with their counterparts living in households with food security. Specifically, FI had a negative association with fruits, vegetables, and protein foods, and a positive association with refined grains consumption. Dairy intake was negatively associated with FI among older children and adolescents. Added sugars were not associated with FI, but intake was excessive across the population at 15% of total daily energy intake. Decreasing FI may help improve dietary quality of Mexican children and adolescents. © 2016 John Wiley & Sons Ltd.

Machismo sustains health and illness beliefs of Mexican American men.

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Sobralske, Mary

2006-08-01

To inform nurse practitioners (NPs) about Mexican American men's health and illness beliefs and the ways in which these are influenced by their masculine identity and how they view themselves as men in their culture. The data sources used were based on a selected review of the literature about Mexican American men's health and illness beliefs and the concept of machismo. Several studies, including the author's study on Mexican American men's healthcare-seeking beliefs and behaviors and experience in providing primary health care to men across cultures, contributed new data. The meaning of manhood in the Mexican American culture is critical in understanding how men perceive health and illness and what they do when they are ill. Machismo enhances men's awareness of their health because they have to be healthy to be good fathers, husbands, brothers, sons, workers, and community members. Pain and disability are motivating factors in finding ways to regain their health. Men's health beliefs across cultures need further investigation by nurse researchers and NPs. How culture influences healthcare delivery to men should be better understood. If NPs are aware of men's views on masculinity, they are better prepared to understand and assist men in becoming more aware of their health status and to seek health care when appropriate.

Gene expression patterns specific to the regenerating limb of the Mexican axolotl

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James R. Monaghan

2012-07-01

Salamander limb regeneration is dependent upon tissue interactions that are local to the amputation site. Communication among limb epidermis, peripheral nerves, and mesenchyme coordinate cell migration, cell proliferation, and tissue patterning to generate a blastema, which will form missing limb structures. An outstanding question is how cross-talk between these tissues gives rise to the regeneration blastema. To identify genes associated with epidermis-nerve-mesenchymal interactions during limb regeneration, we examined histological and transcriptional changes during the first week following injury in the wound epidermis and subjacent cells between three injury types; 1 a flank wound on the side of the animal that will not regenerate a limb, 2 a denervated limb that will not regenerate a limb, and 3 an innervated limb that will regenerate a limb. Early, histological and transcriptional changes were similar between the injury types, presumably because a common wound-healing program is employed across anatomical locations. However, some transcripts were enriched in limbs compared to the flank and are associated with vertebrate limb development. Many of these genes were activated before blastema outgrowth and expressed in specific tissue types including the epidermis, peripheral nerve, and mesenchyme. We also identified a relatively small group of transcripts that were more highly expressed in innervated limbs versus denervated limbs. These transcripts encode for proteins involved in myelination of peripheral nerves, epidermal cell function, and proliferation of mesenchymal cells. Overall, our study identifies limb-specific and nerve-dependent genes that are upstream of regenerative growth, and thus promising candidates for the regulation of blastema formation.

Perceived Discrimination and Mexican-Origin Young Adults' Sleep Duration and Variability: The Moderating Role of Cultural Orientations.

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Zeiders, Katharine H; Updegraff, Kimberly A; Kuo, Sally I-Chun; Umaña-Taylor, Adriana J; McHale, Susan M

2017-08-01

Perceived ethnic discrimination is central to the experiences of Latino young adults, yet we know little about the ways in which and the conditions under which ethnic discrimination relates to Latino young adults' sleep patterns. Using a sample of 246 Mexican-origin young adults (M age  = 21.11, SD = 1.54; 50 % female), the current study investigated the longitudinal links between perceived ethnic discrimination and both sleep duration and night-to-night variability in duration, while also examining the moderating roles of Anglo and Mexican orientations in the associations. The results revealed that perceived discrimination predicted greater sleep variability, and this link was not moderated by cultural orientations. The relation between perceived discrimination and hours of sleep, however, was moderated by Anglo and Mexican orientations. Individuals with high Anglo and Mexican orientations (bicultural) and those with only high Mexican orientations (enculturated), showed no association between discrimination and hours of sleep. Individuals with low Anglo and Mexican orientations (marginalized) displayed a positive association, whereas those with high Anglo and low Mexican orientations (acculturated) displayed a negative association. The results suggest that discrimination has long term effects on sleep variability of Mexican-origin young adults, regardless of cultural orientations; however, for sleep duration, bicultural and enculturated orientations are protective.

Association between Obesity and Serum 25(OH)D Concentrations in Older Mexican Adults.

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Rontoyanni, Victoria G; Avila, Jaqueline C; Kaul, Sapna; Wong, Rebeca; Veeranki, Sreenivas P

2017-01-31

Vitamin D is essential for maintaining bone mineralization and calcium homeostasis, and prevents falls and fractures in older adults. Mexico is undergoing an epidemiologic and demographic transition with increasing obesity rates. The study's aim was to determine the association of obesity with serum 25-hydroxyvitamin D [25(OH)D] concentrations in older Mexican adults. Data from 1772 Mexicans, aged ≥50 years, enrolled in a sub-sample of the 3rd wave of the Mexican Health and Aging Study, were included. Serum 25(OH)D concentrations were used to define vitamin D status, and were categorized into tertiles. Body mass index measures were used to categorize older adults into under/normal weight, overweight, and obese groups. Multinomial logistic regression models were used to assess the relationship, adjusting for potential confounders. Approximately 40% and 37% of older Mexican adults were either overweight or obese, respectively. Compared to under/normal weight older Mexicans, obese adults were 1.78 times (95% Confidence Interval (CI) 1.27-2.48) and 1.94 times (95% CI 1.40-2.68) more associated with the first and second tertile concentrations of serum 25(OH)D, respectively. Overweight adults were 1.52 times (95% CI 1.12-2.06) more associated with the second tertile of serum 25(OH)D concentration than under/normal weight adults. Overweight/Obesity was found to be significantly associated with low concentrations of serum 25(OH) in older Mexican adults.

Extended Family Ties among Mexicans, Puerto Ricans, and Whites: Superintegration or Disintegration?

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Sarkisian, Natalia; Gerena, Mariana; Gerstel, Naomi

2006-01-01

Addressing recent theoretical debates, this study examined the differences in extended family integration among Mexicans, Puerto Ricans, and Whites, as well as the importance of culture and structure in explaining these differences. Our findings showed Whites and Latinos/as have distinctive patterns of extended family integration: Mexicans and…

Usual Vitamin Intakes by Mexican Populations.

Science.gov (United States)

Pedroza-Tobías, Andrea; Hernández-Barrera, Lucía; López-Olmedo, Nancy; García-Guerra, Armando; Rodríguez-Ramírez, Sonia; Ramírez-Silva, Ivonne; Villalpando, Salvador; Carriquiry, Alicia; Rivera, Juan A

2016-09-01

In the past several years, the consumption of high-energy, nutrient-poor foods has increased globally. Dietary intake data collected by the National Health and Nutrition Survey (ENSANUT) 2012 provide information to assess the quality of the Mexican diet and to guide food and nutrition policy. The aim was to describe the usual intake and the prevalence of inadequate intakes of vitamins for the overall Mexican population and by subgroups defined by sex, age, region, urban or rural areas, and socioeconomic status (SES). ENSANUT 2012 is a cross-sectional probabilistic survey representative of the Mexican population. Dietary information was collected by using the 24-h recall automated multiple-pass method (n = 10,096) with a repeated measurement on a subsample (n = 889) to permit adjustment for intraindividual variability with the use of the Iowa State University method. Mean usual intakes and the prevalence of inadequate intakes of thiamin, riboflavin, niacin, folate, and vitamins A, D, E, C, B-6, and B-12 were calculated for children aged 1-4 y (CH1-4y), children aged 5-11 y (CH5-11y), adolescents aged 12-19 y, and adults aged ≥20 y. In all of the age groups, prevalences of inadequate intakes of vitamins D and E were the highest (77-99% of adults and adolescents and 53-95% of CH5-11y and CH1-4y) and those of folate and vitamin A were intermediate (47-70% of adults and adolescents, 15-23% of CH5-11y and 8-13% of CH1-4y), whereas those of thiamin, riboflavin, niacin, and vitamins B-6, B-12, and C were the lowest (0-37% of adults, 1-27% of adolescents, and 0-2.4% of CH5-11y and CH1-4y). With few exceptions, the highest prevalences of inadequate intakes for vitamins were observed in the poorest populations (rural South region and the lowest tertile of SES). The intake of vitamins among Mexicans is inadequate overall. Information collected by ENSANUT can help target food assistance programs and develop strategies to prevent vitamin deficiencies. © 2016 American Society

Mexican-Americans in the Southwest.

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Galarza, Ernesto; And Others

With findings as presented in this 1969 book, a 2-year field study conducted by a 3-member team analyzed the economic, cultural, political, and educational conditions of Mexican Americans in the Southwest (California, Arizona, New Mexico, Colorado, and Texas) with some reference to braceros and the situation in Mexico. An overview of 8 geographic…

La Artesania Mexicana (Mexican Handicrafts).

Science.gov (United States)

Steele, Bettina

This booklet contains instructions in English and Spanish for making eleven typical Mexican craft articles. The instructions are accompanied by pen-and-ink drawings. The objects are (1) "La Rosa" (The Rose); (2) "El Crisantemo" (The Chrysanthemum); (3) "La Amapola" (The Poppy); (4) "Ojos de Dios" (God's Eyes); (5) "Ojitos con dos caras" (Two-Sided…

Unemployment Among Mexican Immigrant Men in the United States, 2003 – 2012

Science.gov (United States)

Laird, Jennifer

2014-01-01

Based on their socioeconomic characteristics, Mexican immigrant men should have very high un-employment. More than half do not have a high school diploma. One in four works in construction; at the height of the recent recession, 20% of construction workers were unemployed. Yet their unemployment rates are similar to those of native-born white men. After controlling for education and occupation, Mexican immigrant men have lower probabilities of unemployment than native-born white men – both before and during the recent recession. I consider explanations based on eligibility for unemployment benefits, out-migrant selection for unemployment, and employer preferences for Mexican immigrant labor. PMID:25432614

Employer Sanctions and the Wages of Mexican Immigrants

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Peter Brownell

2017-07-01

Full Text Available Wage differences between authorized and unauthorized Mexican immigrants can be explained by human capital factors prior to the 1986 passage of employer sanctions, which prohibited knowingly hiring unauthorized aliens. However, a significant post-1986 wage differential has been interpreted as employers “passing along” expected costs of sanctions through lower wages for unauthorized immigrants. I test this explanation using administrative data on employer sanctions enforcement, finding employer sanctions enforcement levels are related to Mexican immigrants’ wages but have no statistically significant differential effect based on legal status. Estimated savings to employers due to the pay gap are orders of magnitude larger than actual fines.

Suicide Ideation, Plan, and Attempt in the Mexican Adolescent Mental Health Survey

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Borges, Guilherme; Benjet, Corina; Medina-Mora, Maria Elena; Orozco, Ricardo; Nock, Matthew

2008-01-01

The study examines data from the Mexican Adolescent Mental Health Survey to study the prevalence and risk factors for suicide ideation, plan, and attempt among Mexican adolescents. The results reveal patterns of the risk factors and suggest that intervention should focus on adolescents with mental disorders to effectively prevent suicides.

Hopelessness, Family Stress, and Depression among Mexican-Heritage Mothers in the Southwest

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Marsiglia, Flavio F.; Kulis, Stephen; Perez, Hilda Garcia; Bermudez-Parsai, Monica

2011-01-01

This article reports on the findings of a study conducted with a sample of 136 Mexican-heritage mothers residing in a large southwestern metropolitan area. From a risk-and-resiliency perspective, hopelessness was approached as a culturally specific response to family stress and other challenges encountered by Mexican immigrants. Although…

3. Mexican school of nuclear physics

International Nuclear Information System (INIS)

Chavez L, E.R.; Hess, P.O.; Martinez Q, E.

2002-01-01

The III Mexican School of Nuclear Physics which is directed to those post graduate in Sciences and those of last semesters students of the Physics career or some adjacent career was organized by the Nuclear Physics Division of the Mexican Physics Society, carrying out at November 18-29, 2002 in the installations of the Institute of Physics and the Institute of Nuclear Sciences both in the UNAM, and the National Institute of Nuclear Research (ININ). In this as well as the last version its were offered 17 courses, 9 of them including laboratory practices and the rest were of theoretical character only. This book treats about the following themes: Nuclear physics, Electrostatic accelerators, Cyclotrons, Thermonuclear reactions, Surface barrier detectors, Radiation detection, Neutron detection, Bonner sphere spectrometers, Radiation protection, Biological radiation effects, Particle kinematics, Nucleosynthesis, Plastics, Muons, Quadrupoles, Harmonic oscillators, Quantum mechanics among many other matters. (Author)

Contribution of Common Genetic Variants to Obesity and Obesity-Related Traits in Mexican Children and Adults

Science.gov (United States)

Villalobos-Comparán, Marisela; Villarreal-Molina, Teresa; Romero-Hidalgo, Sandra; López-Contreras, Blanca; Gutiérrez-Vidal, Roxana; Vega-Badillo, Joel; Jacobo-Albavera, Leonor; Posadas-Romeros, Carlos; Canizalez-Román, Adrián; Río-Navarro, Blanca Del; Campos-Pérez, Francisco; Acuña-Alonzo, Victor; Aguilar-Salinas, Carlos; Canizales-Quinteros, Samuel

2013-01-01

Background Several studies have identified multiple obesity-associated loci mainly in European populations. However, their contribution to obesity in other ethnicities such as Mexicans is largely unknown. The aim of this study was to examine 26 obesity-associated single-nucleotide polymorphisms (SNP) in a sample of Mexican mestizos. Methods 9 SNPs in biological candidate genes showing replications (PPARG, ADRB3, ADRB2, LEPR, GNB3, UCP3, ADIPOQ, UCP2, and NR3C1), and 17 SNPs in or near genes associated with obesity in first, second and third wave GWAS (INSIG2, FTO, MC4R, TMEM18, FAIM2/BCDIN3, BDNF, SH2B1, GNPDA2, NEGR1, KCTD15, SEC16B/RASAL2, NPC1, SFRF10/ETV5, MAF, PRL, MTCH2, and PTER) were genotyped in 1,156 unrelated Mexican-Mestizos including 683 cases (441 obese class I/II and 242 obese class III) and 473 normal-weight controls. In a second stage we selected 12 of the SNPs showing nominal associations with obesity, to seek associations with quantitative obesity-related traits in 3 cohorts including 1,218 Mexican Mestizo children, 945 Mexican Mestizo adults, and 543 Indigenous Mexican adults. Results After adjusting for age, sex and admixture, significant associations with obesity were found for 6 genes in the case-control study (ADIPOQ, FTO, TMEM18, INSIG2, FAIM2/BCDIN3 and BDNF). In addition, SH2B1 was associated only with class I/II obesity and MC4R only with class III obesity. SNPs located at or near FAIM2/BCDIN3, TMEM18, INSIG2, GNPDA2 and SEC16B/RASAL2 were significantly associated with BMI and/or WC in the combined analysis of Mexican-mestizo children and adults, and FTO locus was significantly associated with increased BMI in Indigenous Mexican populations. Conclusions Our findings replicate the association of 8 obesity-related SNPs with obesity risk in Mexican adults, and confirm the role of some of these SNPs in BMI in Mexican adults and children. PMID:23950976

Moving In and Out of Bilingualism: Investigating Native Language Maintenance and Shift in Mexican-Descent Children. Research Report: 6.

Science.gov (United States)

Pease-Alvarez, Lucinda

A study investigated patterns and influences in Mexican-American children's Spanish language maintenance and shift toward English dominance or monolingualism. Subjects were 64 Mexican-descent children, ages 8-9, of varying immigration backgrounds (Mexican-born, U.S.-born of Mexican-born parents, U.S.-born of U.S.-born parents), and their families…

SES Gradients Among Mexicans in the United States and in Mexico: A New Twist to the Hispanic Paradox?

Science.gov (United States)

Beltrán-Sánchez, Hiram; Palloni, Alberto; Riosmena, Fernando; Wong, Rebeca

2016-10-01

Recent empirical findings have suggested the existence of a twist in the Hispanic paradox, in which Mexican and other Hispanic foreign-born migrants living in the United States experience shallower socioeconomic status (SES) health disparities than those in the U.S. In this article, we seek to replicate this finding and test conjectures that could explain this new observed phenomenon using objective indicators of adult health by educational attainment in several groups: (1) Mexican-born individuals living in Mexico and in the United States, (2) U.S.-born Mexican Americans, and (3) non-Hispanic American whites. Our analytical strategy improves upon previous research on three fronts. First, we derive four hypotheses from a general framework that has also been used to explain the standard Hispanic paradox. Second, we study biomarkers rather than self-reported health and related conditions. Third, we use a binational data platform that includes both Mexicans living in Mexico (Mexican National Health and Nutrition Survey 2006) and Mexican migrants to the United States (NHANES 1999-2010). We find steep education gradients among Mexicans living in Mexico's urban areas in five of six biomarkers of metabolic syndrome (MetS) and in the overall MetS score. Mexican migrants living in the United States experience similar patterns to Mexicans living in Mexico in glucose and obesity biomarkers. These results are inconsistent with previous findings, suggesting that Mexican migrants in the United States experience significantly attenuated health gradients relative to the non-Hispanic white U.S. Our empirical evidence also contradicts the idea that SES-health gradients in Mexico are shallower than those in the United States and could be invoked to explain shallower gradients among Mexicans living in the United States.

Age at migration and disability-free life expectancy among the elder Mexican-origin population

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Marc Garcia

2016-12-01

Full Text Available Background: Migration selectivity is thought to shape the health profiles of Mexican immigrants. Objective: This study examines how the experience of Mexican migration to the United States affects the health process and the quality of life in old age by age at migration, specific to sex. Methods: We use 20 years of data from the Hispanic Established Populations for the Epidemiologic Study of the Elderly to estimate the proportion of life spent disability-free prior to death across eight subgroups by sex, nativity, and age at migration among Mexican-origin elderly in the United States. Results: Female migrants are at a significant disadvantage in terms of IADL disability-free life expectancy relative to US-born women, particularly late-life migrants. Conversely, mid- and late-life male migrants exhibit an advantage in ADL disability-free life expectancy compared to their US-born counterparts. Conclusions: Foreign-born Mexican elders are not a homogeneous group. This issue merits special attention in the development of community-based long-term care programs in order to appropriately target the specific needs of different subgroups of older Mexican individuals entering their last decades of life. Contribution: This study contributes to immigrant health literature by providing a more comprehensive documentation of nativity differentials, by distinguishing subgroups of Mexican elderly by sex, nativity, and age at migration.

Market study on the Mexican market for electrical distribution equipment

International Nuclear Information System (INIS)

1991-01-01

A brief historical survey of the development of the Mexican electric power sector is presented, along with an overview of the state of the Mexican economy since the late 1980s and the present characteristics of the Mexican electricity sector. The Mexican market for electric power generation and distribution equipment is then assessed, from the perspective of Canadian suppliers and manufacturers intending to enter this market. Projected consumption of electrical generation and distribution equipment in Mexico for 1994 is estimated at US$1,035,600,000 ($719.4 million in production, $356.9 million in imports, and $40.7 million in exports). This market increased 12.3% in 1990, and since power demand in Mexico has been growing faster than growth in capacity, it is possible that investments in the electricity sector will grow at faster rates. Items which are traditionally imported include nuclear reactors and related equipment, boilers, turbines, power breakers, valves, coal and ash handling equipment, relays, automatic controls, and chemical treatment equipment. The USA has the greatest share of the import market with 35%, followed by Japan (22%), Switzerland (18%), and Germany (13%). Canadian exports have concentrated on distribution equipment and only totalled $1.7 million in 1990. Electricity is distributed to some 16.6 million users over a national interconnected system having total installed capacity of 30,513 MW in 1991. There are plans to increase capacity by 9.7 GW by 1994 and another 37.4-47.8 GW between 1995 and 2010. Projections of electricity needs by region are listed along with the new power plants targeted for investment. Market liberalization and lowering of tariffs have made the Mexican market more accessible to exporters. 8 tabs

4. Mexican School of Nuclear Physics. Papers

International Nuclear Information System (INIS)

Aguilera, E.F.; Hernandez, E.; Hirsch, J.

2005-01-01

The IV Mexican School of Nuclear Physics, organized by the Nuclear Physics Division of the Mexican Physics Society, takes place from June 27 to July 8, 2005 in the Nuclear Sciences and of Physics Institutes of the UNAM and in the National Institute of Nuclear Research (ININ). This school, as the previous ones, it was guided the students of the last semesters of the career of Physics, of the Post grade of the same specialty, and of other adjacent careers. To give the students a current vision of some of the topics more important of the nuclear physics and their relationship with other near areas of the physics it was the objective of this School. The School covered a wide range of theoretical and experimental courses, imparted in its majority by Mexican expert professor-investigators in the matter to who we thank them the one effort and the quality of their presentations, reflected in the content of this document. The answer of the students to the convocation was excellent, 31 students presented application for admission coming from the following institutions: Meritorious Autonomous University de Puebla, National Institute of Nuclear Research, Technological Institute of Orizaba, National Polytechnic Institute, The University of Texas at Brownsville, Autonomous University of the State de Mexico, Autonomous University of the State of Morelos, Autonomous University of Baja California, Autonomous University of San Luis Potosi, University of Guadalajara, University of Guanajuato, National Autonomous University of Mexico, University of Texas, at El Paso and University Veracruzana. They were admitted to the 22 students with the higher averages qualifications of the list of applicants. The organizers of this school thank the financial support granted by the following sponsor institutions: Nuclear Sciences Institute, UNAM, Physics Institute of UNAM, Coordination of the Scientific Research UNAM, National Institute of Nuclear Research, Nuclear Physics Division of the Mexican

Georeferenced Population Datasets of Mexico (GEO-MEX): Raster Based GIS Coverage of Mexican Population

Data.gov (United States)

National Aeronautics and Space Administration — The Raster Based GIS Coverage of Mexican Population is a gridded coverage (1 x 1 km) of Mexican population. The data were converted from vector into raster. The...

San Pedro Martir Telescope: Mexican design endeavor

Science.gov (United States)

Toledo-Ramirez, Gengis K.; Bringas-Rico, Vicente; Reyes, Noe; Uribe, Jorge; Lopez, Aldo; Tovar, Carlos; Caballero, Xochitl; Del-Llano, Luis; Martinez, Cesar; Macias, Eduardo; Lee, William; Carramiñana, Alberto; Richer, Michael; González, Jesús; Sanchez, Beatriz; Lucero, Diana; Manuel, Rogelio; Segura, Jose; Rubio, Saul; Gonzalez, German; Hernandez, Obed; García, Mary; Lazaro, Jose; Rosales-Ortega, Fabian; Herrera, Joel; Sierra, Gerardo; Serrano, Hazael

2016-08-01

The Telescopio San Pedro Martir (TSPM) is a new ground-based optical telescope project, with a 6.5 meters honeycomb primary mirror, to be built in the Observatorio Astronomico Nacional on the Sierra San Pedro Martir (OAN-SPM) located in Baja California, Mexico. The OAN-SPM has an altitude of 2830 meters above sea level; it is among the best location for astronomical observation in the world. It is located 1830 m higher than the atmospheric inversion layer with 70% of photometric nights, 80% of spectroscopic nights and a sky brightness up to 22 mag/arcsec2. The TSPM will be suitable for general science projects intended to improve the knowledge of the universe established on the Official Mexican Program for Science, Technology and Innovation 2014-2018. The telescope efforts are headed by two Mexican institutions in name of the Mexican astronomical community: the Universidad Nacional Autonoma de Mexico and the Instituto Nacional de Astrofisica, Optica y Electronica. The telescope has been financially supported mainly by the Consejo Nacional de Ciencia y Tecnologia (CONACYT). It is under development by Mexican scientists and engineers from the Center for Engineering and Industrial Development. This development is supported by a Mexican-American scientific cooperation, through a partnership with the University of Arizona (UA), and the Smithsonian Astrophysical Observatory (SAO). M3 Engineering and Technology Corporation in charge of enclosure and building design. The TSPM will be designed to allow flexibility and possible upgrades in order to maximize resources. Its optical and mechanical designs are based upon those of the Magellan and MMT telescopes. The TSPM primary mirror and its cell will be provided by the INAOE and UA. The telescope will be optimized from the near ultraviolet to the near infrared wavelength range (0.35-2.5 m), but will allow observations up to 26μm. The TSPM will initially offer a f/5 Cassegrain focal station. Later, four folded Cassegrain and

Father involvement in Mexican-origin families: Preliminary development of a culturally informed measure.

Science.gov (United States)

Roubinov, Danielle S; Luecken, Linda J; Gonzales, Nancy A; Crnic, Keith A

2016-04-01

An increasing body of research has documented the significant influence of father involvement on children's development and overall well-being. However, extant research has predominately focused on middle-class Caucasian samples with little examination of fathering in ethnic minority and low-income families, particularly during the infancy period. The present study evaluated measures of early father involvement (paternal engagement, accessibility, and responsibility) that were adapted to capture important cultural values relevant to the paternal role in Mexican-origin families. A sample of 180 Mexican-origin mothers (M age = 28.3) and 83 Mexican-origin fathers (M age = 31.5) were interviewed during the perinatal period. Descriptive analyses indicated that Mexican-origin fathers are involved in meaningful levels of direct interaction with their infant. A 2-factor model of paternal responsibility was supported by factor analyses, consisting of a behavioral responsibility factor aligned with previous literature and culturally derived positive machismo factor. Qualities of the romantic relationship, cultural orientation, and maternal employment status were related to indices of father involvement. These preliminary results contribute to understanding of the transition to fatherhood among low-income Mexican-origin men and bring attention to the demographic, social, and cultural contexts in which varying levels of father involvement may emerge. (c) 2016 APA, all rights reserved).

Reasons for self-medication and perceptions of risk among Mexican migrant farm workers.

Science.gov (United States)

Horton, Sarah; Stewart, Analisia

2012-08-01

Although the frequency of self-medication among Mexican migrants has been well-documented in the public health literature, the multiple reasons for this practice are poorly understood. Most studies point to migrants' cultural preferences for Mexican medications, their prior experiences in countries where antibiotics are loosely regulated, and their lack of access to health care as the primary factors behind their self-medication. Based on participant observation and in-depth interviews with 23 Mexican migrants in a farm working community in the interior of California, we argue that occupational vulnerability is an equally important factor that encourages self-medication. All 23 of our interviewees reported having engaged in some degree of self-medication, notable in this location 8 h from the US-Mexico border. Among interviewees, occupational vulnerability represented an even more important factor influencing self-medication than lack of health insurance or lack of legal documentation. While interviewees did express a preference for Mexican medications as more potent and effective, this did not necessarily translate to a preference for using them without a doctor's supervision. Finally, we show that rather than remaining unaware of the risks of following this custom "transported from Latin America", Mexican migrants devised an elaborate hierarchy of resort of the safest self-medication practices to follow.

Barreda, Vasconcelos, and Mexican Educational Reforms.

Science.gov (United States)

Skirius, John

1983-01-01

Reviews the contributions to Mexican education of Gabino Barredas' positivism between 1867-1898 and the contributions of Jose Vasconcelos during the 1920s. Discusses the secondary curriculum reforms of Barreda's era and the vocational education and the education for women and adults during the Vasconcelos era. (SB)

Immigration and Wage Dynamics: Evidence from the Mexican Peso Crisis

OpenAIRE

Monras , Joan

2015-01-01

How does the US labor market absorb low-skilled immigration? I address this question using the 1995 Mexican Peso Crisis, an exogenous push factor that raised Mexican migration to the US. In the short run, high-immigration states see their low-skilled labor force increase and native low-skilled wages decrease, with an implied local labor demand elasticity of -.7. Internal relocation dissipates this shock spatially. In the long run, the only lasting consequences are for low-skilled natives who ...

Genetic ancestry in relation to the metabolic response to a U.S. versus traditional Mexican diet: a randomized crossover feeding trial among women of Mexican descent

OpenAIRE

Santiago-Torres, Margarita; De Dieu Tapsoba, Jean; Kratz, Mario; Lampe, Johanna W.; Breymeyer, Kara L.; Levy, Lisa; Song, Xiaoling; Villase?or, Adriana; Wang, Ching-Yun; Fejerman, Laura; Neuhouser, Marian L.; Carlson, Christopher S.

2016-01-01

Background Certain populations with a large proportion of Indigenous American (IA) genetic ancestry may be evolutionarily adapted to traditional diets high in legumes and complex carbohydrates, and may have a detrimental metabolic response to U.S. diets high in refined carbohydrates and added sugars. We tested whether IA ancestry modified the metabolic response to a U.S. versus traditional Mexican diet in a controlled dietary intervention. Methods First and second generation Mexican immigrant...

Methodological Appendix of Research Methods Employed in the Mexican American Education Study.

Science.gov (United States)

Commission on Civil Rights, Washington, DC.

The U.S. Commission on Civil Rights released Mexican American Education Study findings in a series of documents: (1) "The Ethnic Isolation of Mexican Americans in the Public Schools of the Southwest" (ED 052 849), "The Unfinished Education" (ED 056 821), and "The Excluded Student" (ED 062 069). The research methods employed in the study are…

Mexican American Mothers' Perceptions of Childhood Obesity: A Theory-Guided Systematic Literature Review

Science.gov (United States)

Sosa, Erica T.

2012-01-01

Childhood obesity continues to increase, disproportionately affecting Mexican American children. The aims of this review are to (a) assess the literature regarding Mexican American mothers' knowledge and perceptions of childhood obesity, prevention, and their role in prevention; (b) critically evaluate the methodological quality of the research…

FastStats: Health of Mexican American Population

Science.gov (United States)

... Submit Button NCHS Home Health of Mexican American Population Recommend on Facebook Tweet Share Compartir Data are ... Source: Summary Health Statistics Tables for the U.S. Population: National Health Interview Survey, 2015, Table P-1c [ ...

Parental perceptions of childhood overweight in the Mexican American population: an integrative review.

Science.gov (United States)

Ward, Carroll L

2008-12-01

The prevalence of overweight in Mexican American children has been increasing at a steady rate over the past few years. People of Mexican origin make up the largest proportion of the Hispanic population, which has been reported by the U.S. Census Bureau to be the fastest growing ethnic group in the United States. The purpose of this integrative review was to examine and summarize the current research on parental perceptions of childhood overweight in the Mexican American population. Four main themes evolved as a result of the data analysis: parental perception of overweight, parental practices, household food security status, and acculturation. School nurses are in a position to influence children in improving their nutritional status and increasing their physical activity. Understanding cultural values and beliefs regarding health status and overweight of Mexican American families should be a priority for school nurses. Identifying food-related parenting styles and the concept of acculturation should also be considered prior to incorporating relevant interventions in the school setting.

Couples' cultural values, shared parenting, and family emotional climate within Mexican American families.

Science.gov (United States)

Sotomayor-Peterson, Marcela; Figueredo, Aurelio J; Christensen, Donna H; Taylor, Angela R

2012-06-01

This study tested a model of shared parenting as its centerpiece that incorporates cultural values as predictors and family emotional climate as the outcome variable of interest. We aimed to assess the predictive power of the Mexican cultural values of familismo and simpatia over couples' shared parenting practices. We anticipated that higher levels of shared parenting would predict family emotional climate. The participants were 61 Mexican American, low income couples, with at least one child between 3 and 4 years of age, recruited from a home-based Head Start program. The predictive model demonstrated excellent goodness of fit, supporting the hypothesis that a positive emotional climate within the family is fostered when Mexican American couples practice a sufficient level of shared parenting. Empirical evidence was previously scarce on this proposition. The findings also provide evidence for the role of cultural values, highlighting the importance of family solidarity and avoidance of confrontation as a pathway to shared parenting within Mexican American couples. © FPI, Inc.

Family and Cultural Correlates of Mexican-origin Youths’ Sexual Intentions

Science.gov (United States)

Killoren, Sarah E.; Updegraff, Kimberly A.; Christopher, F. Scott

2013-01-01

Understanding how culture and familial relationships are related to Mexican-origin youths’ normative sexual development is important. Using cultural-ecological, sexual scripting, and risk and resilience perspectives, the associations between parent-adolescent relationship characteristics, adolescents’ cultural orientations and familism values, and sexual intentions among 246 Mexican-origin adolescents (50% female) were investigated. Regression analyses were conducted to examine the connections between youths’ cultural orientations and familism values and their intentions to engage in sexual intercourse and to test the moderating role of parent-adolescent relationship characteristics and adolescent sex. For boys, under conditions of high maternal acceptance, higher Anglo orientations and higher Mexican orientations were related to greater sexual intentions. For girls, familism values played a protective role and were related to fewer sexual intentions when girls spent less time with their parents. The findings highlight the complex nature of relationships between culture, family relationships, and youths’ sexual intentions and different patterns for girls versus boys. PMID:20835919

Family and cultural correlates of Mexican-origin youths' sexual intentions.

Science.gov (United States)

Killoren, Sarah E; Updegraff, Kimberly A; Christopher, F Scott

2011-06-01

Understanding how culture and familial relationships are related to Mexican-origin youths' normative sexual development is important. Using cultural-ecological, sexual scripting, and risk and resilience perspectives, the associations between parent-adolescent relationship characteristics, adolescents' cultural orientations and familism values, and sexual intentions among 246 Mexican-origin adolescents (50% female) were investigated. Regression analyses were conducted to examine the connections between youths' cultural orientations and familism values and their intentions to engage in sexual intercourse and to test the moderating role of parent-adolescent relationship characteristics and adolescent sex. For boys, under conditions of high maternal acceptance, higher Anglo orientations and higher Mexican orientations were related to greater sexual intentions. For girls, familism values played a protective role and were related to fewer sexual intentions when girls spent less time with their parents. The findings highlight the complex nature of relationships between culture, family relationships, and youths' sexual intentions and different patterns for girls versus boys.

Finite-time singularities in the dynamics of Mexican financial crises

Science.gov (United States)

Alvarez-Ramirez, Jose; Ibarra-Valdez, Carlos

2004-01-01

Historically, symptoms of Mexican financial crises have been strongly reflected in the dynamics of the Mexican peso to the dollar exchange currency market. Specifically, in the Mexican financial crises during 1990's, the peso suffered significant depreciation processes, which has important impacts in the macro- and micro-economical environment. In this paper, it is shown that the peso depreciation growth was greater than an exponential and that these growth rates are compatible with a spontaneous singularity occurring at a critical time, which signals an abrupt transition to new dynamical conditions. As in the major 1990's financial crisis in 1994-1995, some control actions (e.g., increasing the USA dollar supply) are commonly taken to decelerate the degree of abruptness of peso depreciation. Implications of these control actions on the crisis dynamics are discussed. Interestingly, by means of a simple model, it is demonstrated that the time at which the control actions begin to apply is critical to moderate the adverse effects of the financial crisis.

Alkaline pretreatment of Mexican pine residues for bioethanol ...

African Journals Online (AJOL)

Alkaline pretreatment of Mexican pine residues for bioethanol production. ... Keywords: Lignocellulosic biomass, alkaline pretreatment, enzymatic hydrolysis, fermentable sugars, fermentation. African Journal of Biotechnology Vol. 12(31), pp.

Metabolic syndrome prevalence among Northern Mexican adult population.

Science.gov (United States)

Salas, Rogelio; Bibiloni, Maria del Mar; Ramos, Esteban; Villarreal, Jesús Z; Pons, Antoni; Tur, Josep A; Sureda, Antoni

2014-01-01

Dietary habits in the Mexican population have changed dramatically over the last few years, which are reflected in increased overweight and obesity prevalence. The aim was to examine the prevalence of metabolic syndrome (MetS) and associated risk factors in Northern Mexican adults aged ≥ 16 years. The study was a population-based cross-sectional nutritional survey carried out in the State of Nuevo León, Mexico. The study included a sub-sample of 1,200 subjects aged 16 and over who took part in the State Survey of Nutrition and Health-Nuevo León 2011/2012. Anthropometric measurements, physical activity, blood pressure and fasting blood tests for biochemical analysis were obtained from all subjects. The prevalence of MetS in Mexican adults aged ≥ 16 years was 54.8%, reaching 73.8% in obese subjects. This prevalence was higher in women (60.4%) than in men (48.9%) and increased with age in both genders. Multivariate analyses showed no evident relation between MetS components and the level of physical activity. Obese adults, mainly women, are particularly at risk of developing MetS, with the associated implications for their health. The increasing prevalence of MetS highlights the need for developing strategies for its early detection and prevention.

Metabolic syndrome prevalence among Northern Mexican adult population.

Directory of Open Access Journals (Sweden)

Rogelio Salas

Full Text Available Dietary habits in the Mexican population have changed dramatically over the last few years, which are reflected in increased overweight and obesity prevalence. The aim was to examine the prevalence of metabolic syndrome (MetS and associated risk factors in Northern Mexican adults aged ≥ 16 years.The study was a population-based cross-sectional nutritional survey carried out in the State of Nuevo León, Mexico. The study included a sub-sample of 1,200 subjects aged 16 and over who took part in the State Survey of Nutrition and Health-Nuevo León 2011/2012. Anthropometric measurements, physical activity, blood pressure and fasting blood tests for biochemical analysis were obtained from all subjects. The prevalence of MetS in Mexican adults aged ≥ 16 years was 54.8%, reaching 73.8% in obese subjects. This prevalence was higher in women (60.4% than in men (48.9% and increased with age in both genders. Multivariate analyses showed no evident relation between MetS components and the level of physical activity.Obese adults, mainly women, are particularly at risk of developing MetS, with the associated implications for their health. The increasing prevalence of MetS highlights the need for developing strategies for its early detection and prevention.

The Center for Regenerative Biology and Medicine at Mount Desert Island Biological Laboratory

Science.gov (United States)

2015-08-01

TERMS limb regeneration Positional Memory Code Axolotl microRNAs Zebrafish Polypterus 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18...injury induced regeneration of limbs/appendage tissues in Ambystoma ( axolotl ) and Polypterus animals. The defining feature of limb/appendage...downregulated in UPREGULATED DOWNREGULATED Figure 1: Venn diagram of UniProt protein sequence IDs among Axolotl and Polypterus contigs that

Open Access to Mexican Academic Production

Science.gov (United States)

Adame, Silvia I.; Llorens, Luis

2016-01-01

This paper presents a description of the metadata harvester software development. This system provides access to reliable and quality educational resources, shared by Mexican Universities through their repositories, to anyone with Internet Access. We present the conceptual and contextual framework, followed by the technical basis, the results and…

Supporting Two Households: Unaccompanied Mexican Minors and Their Absences from U.S. Schools

Science.gov (United States)

Martinez, Isabel

2016-01-01

This article illustrates simultaneous household participation in the lives of undocumented, unaccompanied Mexican teenage minors in New York City and its impact on their school attendance. Emigrating without parents, some Mexican youths arrive to enter into the labor market, not school. Unable to assume monetary dependence, these youths' absences…

Sleep Moderates and Mediates the Relationship Between Acculturation and Depressive Symptoms in Pregnant Mexican-American Women.

Science.gov (United States)

D'Anna-Hernandez, Kimberly L; Garcia, Esmeralda; Coussons-Read, Mary; Laudenslager, Mark L; Ross, Randal G

2016-02-01

Greater acculturation is associated with adverse perinatal outcomes in Mexican-American women, but the mechanisms by which acculturation influences perinatal outcomes are unclear. Pregnant acculturated Mexican-American women are more likely to engage in unhealthy prenatal behaviors relative to those less acculturated, including poor sleep. As sleep disruptions are associated with acculturation and negative perinatal outcomes, particularly maternal depression, alterations in sleep may adversely affect pregnant Mexican-American women. Sixty pregnant women of Mexican descent completed surveys about sleep, acculturation, depressive symptoms and potential protective factor of social support. Acculturation, but not social support, significantly predicted increased sleep disruptions as well as overall feeling less refreshed upon waking across pregnancy. Moderation analysis indicated that more acculturated women who took longer to fall asleep reported increased depressive symptoms. Feeling refreshed upon waking also mediated the relationship between increased acculturation and elevated maternal depressive symptoms. Acculturation and altered sleep contribute to greater risk in Mexican-American women for maternal depressive symptoms in the perinatal period. These findings have implications for prevention and treatment of maternal mental health disorders, which may adversely affect perinatal outcomes in the vulnerable Mexican-American population.

Mexican Ancestry, Immigrant Generation, and Educational Attainment in the United States

Directory of Open Access Journals (Sweden)

Stephen L. Morgan

2014-09-01

Full Text Available After introducing alternative perspectives on assimilation and acculturation, we use the 2002-2012 waves of the Education Longitudinal Study to model differences in educational attainment for students sampled as high school sophomores in 2002. We focus on patterns observed for the growing Mexican immigrant population, analyzing separately the trajectories of 1st, 1.5th, 2nd, and 3rd+ generation Mexican immigrant students, in comparison to 3rd+ generation students who self-identify as non-Hispanic whites and students who self-identify as non-Hispanic blacks or African Americans. The results suggest that the dissonant acculturation mechanism associated with the segmented assimilation perspective is mostly unhelpful for explaining patterns of educational attainment, especially for the crucial groups of 1.5th and 2nd generation Mexican immigrant students. Instead, standard measures of family background can account for large portions of group differences in bachelor’s degree attainment, with or without additional adjustments for behavioral commitment to schooling, occupational plans, and educational expectations. The broad structure of inequality in the United States, as well as the rising costs of bachelor’s degrees, should be the primary source of concern when considering the prospects for the incorporation of the children of recent Mexican immigrants into the mainstream.

Perceived discrimination and health among Puerto Rican and Mexican Americans: buffering effect of the Lazo matrimonial?

Science.gov (United States)

Lee, Min-Ah; Ferraro, Kenneth F

2009-06-01

An emerging body of research shows that perceived discrimination adversely influences the mental health of minority populations, but is it also deleterious to physical health? If yes, can marriage buffer the effect of perceived discrimination on physical health? We address these questions with data from Puerto Rican and Mexican American residents of Chicago. Multivariate regression analyses reveal that perceived discrimination is associated with more physical health problems for both Puerto Rican and Mexican Americans. In addition, an interaction effect between marital status and perceived discrimination was observed: married Mexican Americans with higher perceived discrimination had fewer physical health problems than their unmarried counterparts even after adjusting for differential effects of marriage by nativity. The findings reveal that perceived discrimination is detrimental to the physical health of both Puerto Rican and Mexican Americans, but that the stress-buffering effect of marriage on physical health exists for Mexican Americans only.

Prevalence of metabolic syndrome among elderly Mexicans.

Science.gov (United States)

Ortiz-Rodríguez, María Araceli; Yáñez-Velasco, Lucía; Carnevale, Alessandra; Romero-Hidalgo, Sandra; Bernal, Demetrio; Aguilar-Salinas, Carlos; Rojas, Rosalba; Villa, Antonio; Tur, Josep A

2017-11-01

One of the most prevalent chronic diseases among elderly population is the Metabolic Syndrome (MetS). The aim of this study was to assess the prevalence of MetS and associated factors among Mexican elderly people. Cross-sectional survey carried out in Mexico (2007). A random sample (n=516) of the elderly population (≥65years; 277 female, 239 male) was interviewed. Anthropometric and analytical measurements, and a general questionnaire incorporating questions related to socio-demographic and life-style factors were used. MetS definition AHA/NHLBI/IDF was applied. The prevalence of MetS in the elderly (≥65years) was of 72.9% (75.7% men; 70.4% women). Participants with values above MetS cut-off points were 92.4% (hypertension), 77.8% (hypertriglyceridemia), 77.1% (low HDL-cholesterol), 71.1% (hyperglycaemia), and 65.4% (central obesity). People with MetS showed higher values of anthropometric and biochemical variables than those without MetS, except for the height, cholesterol and creatinine. Mid-high education level (9-12 years), no smokers and former smokers, and Central-Western inhabitants of Mexico were associated with MetS components. BMI status was the main determinant of MetS prevalence and MetS components. The reported prevalence of MetS among the elderly Mexican population was higher than those previously obtained in the geographical area, showing a major public health problem in Mexican elders. Copyright © 2017 Elsevier B.V. All rights reserved.

Stories of Social Class: Self-Identified Mexican Male College Students Crack the Silence

Science.gov (United States)

Schwartz, Jana L.; Donovan, Jody; Guido-DiBrito, Florence

2009-01-01

This study explores the meaning of social class in the lives of five self-identified Mexican male college students. Participants shared the significant influence social class has on their college experience. Intersections of social class and students' Mexican identity are illuminated throughout the findings. Themes include: social class rules and…

Becoming Overweight Without Gaining a Pound: Weight Evaluations and the Social Integration of Mexicans in the United States.

Science.gov (United States)

Altman, Claire E; Van Hook, Jennifer; Gonzalez, Jonathan

2017-01-01

Mexican women gain weight with increasing duration in the United States. In the United States, body dissatisfaction tends to be associated with depression, disordered eating, and incongruent weight evaluations, particularly among white women and women of higher socioeconomic status. However, it remains unclear how overweight and obesity is interpreted by Mexican women. Using comparable data of women ages 20-64 from both Mexico (the 2006 Encuesta Nacional de Salud y Nutricion; N=17,012) and the United States (the 1999-2009 National Health and Nutrition Examination Surveys; N=8,487), we compare weight status evaluations among Mexican nationals, Mexican immigrants, U.S.-born Mexicans, U.S.-born non-Hispanic Whites, and U.S.-born non-Hispanic blacks. Logistic regression analyses, which control for demographic and social-economic variables and measured body mass index and adjust for the likelihood of migration for Mexican nationals, indicate that the tendency to self-evaluate as overweight among Mexicans converges with levels among non-Hispanic whites and diverges from blacks over time in the United States. Overall, the results suggest a U.S. integration process in which Mexican-American women's less critical self-evaluations originate in Mexico but fade with time in the United States as they gradually adopt U.S. white norms for thinner body sizes. These results are discussed in light of social comparison and negative health assimilation.

The shape of things to come? Obesity prevalence among foreign-born vs. US-born Mexican youth in California.

Science.gov (United States)

Buttenheim, Alison M; Pebley, Anne R; Hsih, Katie; Chung, Chang Y; Goldman, Noreen

2013-02-01

Obesity among the Mexican-origin adult population in the US has been associated with longer stays in the US and with being US- vs. Mexican-born, two proxies for acculturation. This pattern is less clear for Mexican-origin children and young adults: recent evidence suggests that it may be reversed, with foreign-born Mexican youth in the US at higher risk of obesity than their US-born Mexican-American counterparts. The objective of this study is to evaluate the hypothesis that the immigrant advantage in obesity prevalence for Mexican-origin populations in the US does not hold for children and young adults. We use data from the Los Angeles Family and Neighborhood Survey (N = 1143) and the California Health Interview Survey (N = 25,487) for respondents ages 4-24 to calculate the odds of overweight/obesity by ethnicity and nativity. We find support for the hypothesis that overweight/obesity prevalence is not significantly lower for first-generation compared to second- and third-generation Mexican-origin youth. Significantly higher obesity prevalence among the first generation was observed for young adult males (ages 18-24) and adolescent females (ages 12-17). The previously-observed protective effect against obesity risk among recent adult immigrants does not hold for Mexican-origin youth. Copyright © 2012 Elsevier Ltd. All rights reserved.

Decision Profiles of Mexican-Descent Families.

Science.gov (United States)

Baker, Georgianne

An exploratory study of decision-making in families of Mexican heritage was carried out in Phoenix, Arizona. A Normative model of decision rationality and measurement (Family Problem Instrument-FPI) was adapted from previous research. Tape-recorded data were provided by 27 families. Husbands and wives responded separately to family decision…

Feminist Refiguring of La Malinche in Sandra Cisneros’ Never Marry A Mexican

Directory of Open Access Journals (Sweden)

Dian Natalia Sutanto

2016-12-01

Full Text Available La Malinche, the mistress of Spanish conquistador Hernán Cortés, has evolved from a historical figure into Mexican national myth that connotes all the negative aspects of woman’s sexuality in Mexican and Mexican-American Culture. Sandra Cisneros in her Never Marry A Mexican reinterpretsLa Malinchein a more positive light and points out how women sexuality can be the site for women empowerment.By drawing on insights from feminist theories on motherhood, marriage, and incest taboo, this study identifies the way Cisneros revises the negative image of La Malinche as a dupe, passive and submissive mistress. This study identifies that Cisneros has created a strong protagonist character named Clemencia, who exerts her subjectivity and claims for her sexual agency totransgress patriarchal construction of woman passive sexuality, imposition of maternal identity as asexual mother and taboo on incestuous relationship. Cisneros’s La Malinche is no longer depicted as the victim duped by the patriarchy, but as the survivor who is able to preserve her sense of herself in the dominating patriarchal world.   DOI: https://doi.org/10.24071/llt.2015.180103

Protective factors for HIV infection among Mexican American men who have sex with men.

Science.gov (United States)

Meyer, Mark A; Champion, Jane Dimmitt

2010-01-01

Latinos in the United States have been disproportionately affected by the HIV epidemic. The purpose of this study was to identify potential themes for inclusion in effective HIV prevention interventions for Mexican American men who have sex with men (MSM). The authors used a phenomenological design to explore the lived experiences of Mexican American MSM who had grown up in Dallas, Texas, regarding protective factors for HIV infection. A total of 20 30- to 60-year-old Mexican American MSM participated in semistructured interviews. During data analysis, the following themes concerning protective behaviors for HIV emerged: (a) accepting one's sexuality; (b) machismo; (c) being in love; (d) respect for family, self, and life; and (e) having HIV-living now. Strategies for potential inclusion in HIV prevention interventions geared toward Mexican American MSM were identified based on these themes. The recommendations encompass modification of behavioral interventions and related social policies.

Analysis of the expression and function of Wnt-5a and Wnt-5b in developing and regenerating axolotl (Ambystoma mexicanum) limbs.

Science.gov (United States)

Ghosh, Sukla; Roy, Stéphane; Séguin, Carl; Bryant, Susan V; Gardiner, David M

2008-05-01

Urodele amphibians are unique adult vertebrates because they are able to regenerate body parts after amputation. Studies of urodele limb regeneration, the key model system for vertebrate regeneration, have led to an understanding of the origin of blastema cells and the importance of positional interactions between blastema cells in the control of growth and pattern formation. Progress is now being made in the identification of the signaling pathways that regulate dedifferentiation, blastema morphogenesis, growth and pattern formation. Members of the Wnt family of secreted proteins are expressed in developing and regenerating limbs, and have the potential to control growth, pattern formation and differentiation. We have studied the expression of two non-canonical Wnt genes, Wnt-5a and Wnt-5b. We report that they are expressed in equivalent patterns during limb development and limb regeneration in the axolotl (Ambystoma mexicanum), and during limb development in other tetrapods, implying conservation of function. Our analysis of the effects of ectopic Wnt-5a expression is consistent with the hypothesis that canonical Wnt signaling functions during the early stages of regeneration to control the dedifferentiation of stump cells giving rise to the regeneration-competent cells of the blastema.

Enzyme activities and microbial indices of Mexican volcanic soils under different managements

International Nuclear Information System (INIS)

Pajares, S.; Gallardo, J. F.; Masciandaro, G.; Ceccanti, B.; Etchevers, J. D.; Marinari, S.

2009-01-01

Soils at the Mexican Trans-volcanic Belt are extremely important because the lack of agricultural land in overpopulated areas in Mexico. In addition, contents of soil organic matter (SOM) have been declining since the Mexican fields have been cultivated intensively. The aim of this work was to study how different agricultural management practices affect the SOM quality, using biochemical and microbiological parameters as indices. (Author)

β-cell function is associated with metabolic syndrome in Mexican subjects

OpenAIRE

Baez-Duarte, Blanca G; Sánchez-Guillén, María Del Carmen; Pérez-Fuentes, Ricardo; Zamora-Ginez, Irma; Leon-Chavez, Bertha Alicia; Revilla-Monsalve, Cristina; Islas-Andrade, Sergio

2010-01-01

Aims The clinical diagnosis of metabolic syndrome does not find any parameters to evaluate the insulin sensitivity (IS) or β-cell function. The evaluation of these parameters would detect early risk of developing metabolic syndrome. The aim of this study is to determine the relationship between β-cell function and presence of metabolic syndrome in Mexican subjects. Material and methods This study is part of the Mexican Survey on the Prevention of Diabetes (MexDiab Study) with headquarters in ...

Chemical Composition and Biological Activities of Fragrant Mexican Copal (Bursera spp.).

Science.gov (United States)

Gigliarelli, Giulia; Becerra, Judith X; Curini, Massimo; Marcotullio, Maria Carla

2015-12-12

Copal is the Spanish word used to describe aromatic resins from several genera of plants. Mexican copal derives from several Bursera spp., Protium copal, some Pinus spp. (e.g., P. pseudostrobus) and a few Fabaceae spp. It has been used for centuries as incense for religious ceremonies, as a food preservative, and as a treatment for several illnesses. The aim of this review is to analyze the chemical composition and biological activity of commercial Mexican Bursera copal.

Unauthorized Mexican workers in the 1990 Los Angeles County labour force.

Science.gov (United States)

Marcelli, E A; Heer, D M

1997-01-01

"By analysing how unauthorized Mexicans compare with seven other ethno-racial groups in Los Angeles County, separately and collectively, by educational attainment and time spent in the U.S., we find that unauthorized Mexicans had relatively fewer years of formal education (either in the U.S. or in Mexico) and had been in the U.S. a relatively fewer number of years than in-migrants of other ethno-racial backgrounds in 1990. These findings are then used as proxies to compare the human capital endowments of different ethno-racial groups. We next estimate the number of unauthorized Mexicans by occupation, industry and class of worker, and compare these distributions with the total labour force and with the other ethno-racial groups in Los Angeles County.... Results show that amounts of human capital are positively related to the kinds of occupations filled." (SUMMARY IN FRE AND SPA) excerpt

Genetic structure of seven Mexican indigenous populations based on five polymarker loci.

Science.gov (United States)

Buentello-Malo, Leonora; Peñaloza-Espinosa, Rosenda I; Loeza, Francisco; Salamanca-Gomez, Fabio; Cerda-Flores, Ricardo M

2003-01-01

This descriptive study investigates the genetic structure of seven Mexican indigenous populations (Mixteca Alta, Mixteca Baja, Otomies, Purepecha, Nahuas-Guerrero, Nahuas-Xochimilco, and Tzeltales) on the basis of five PCR-based polymorphic DNA loci: LDLR, GYPA, HBGG, D7S8, and GC. Genetic distance and diversity analyses indicate that these Mexican indigenous are similar and that more than 96% of the total gene diversity (H(T)) can be attributed to individual variation within populations. Mixteca-Alta, Mixteca-Baja, and Nahuas-Xochimilco show indications of higher admixture with European-derived persons. The demonstration of a relative genetic homogeneity of Mexican Indians for the markers studied suggests that this population is suitable for studying disease-marker associations in the search for candidate genes of complex diseases. Copyright 2002 Wiley-Liss, Inc.

Conflict Resolution between Mexican Origin Adolescent Siblings

Science.gov (United States)

Killoren, Sarah E.; Thayer, Shawna M.; Updegraff, Kimberly A.

2008-01-01

We investigated correlates of adolescents' sibling conflict resolution strategies in 246, two-parent Mexican origin families. Specifically, we examined links between siblings' conflict resolution strategies and sibling dyad characteristics, siblings' cultural orientations and values, and sibling relationship qualities. Data were gathered during…

DiI Perfusion as a Method for Vascular Visualization in Ambystoma mexicanum.

Science.gov (United States)

Saltman, Anna J; Barakat, May; Bryant, Donald M; Brodovskaya, Anastasia; Whited, Jessica L

2017-06-16

Perfusion techniques have been used for centuries to visualize the circulation of tissues. Axolotl (Ambystoma mexicanum) is a species of salamander that has emerged as an essential model for regeneration studies. Little is known about how revascularization occurs in the context of regeneration in these animals. Here we report a simple method for visualization of the vasculature in axolotl via perfusion of 1,1'-Dioctadecy-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI). DiI is a lipophilic carbocyanine dye that inserts into the plasma membrane of endothelial cells instantaneously. Perfusion is done using a peristaltic pump such that DiI enters the circulation through the aorta. During perfusion, dye flows through the axolotl's blood vessels and incorporates into the lipid bilayer of vascular endothelial cells upon contact. The perfusion procedure takes approximately one hour for an eight-inch axolotl. Immediately after perfusion with DiI, the axolotl can be visualized with a confocal fluorescent microscope. The DiI emits light in the red-orange range when excited with a green fluorescent filter. This DiI perfusion procedure can be used to visualize the vascular structure of axolotls or to demonstrate patterns of revascularization in regenerating tissues.

Metabolic Syndrome Prevalence among Northern Mexican Adult Population

Science.gov (United States)

Salas, Rogelio; Bibiloni, Maria del Mar; Ramos, Esteban; Villarreal, Jesús Z.; Pons, Antoni; Tur, Josep A.; Sureda, Antoni

2014-01-01

Background and Aims Dietary habits in the Mexican population have changed dramatically over the last few years, which are reflected in increased overweight and obesity prevalence. The aim was to examine the prevalence of metabolic syndrome (MetS) and associated risk factors in Northern Mexican adults aged ≥16 years. Methods and Results The study was a population-based cross-sectional nutritional survey carried out in the State of Nuevo León, Mexico. The study included a sub-sample of 1,200 subjects aged 16 and over who took part in the State Survey of Nutrition and Health–Nuevo León 2011/2012. Anthropometric measurements, physical activity, blood pressure and fasting blood tests for biochemical analysis were obtained from all subjects. The prevalence of MetS in Mexican adults aged ≥16 years was 54.8%, reaching 73.8% in obese subjects. This prevalence was higher in women (60.4%) than in men (48.9%) and increased with age in both genders. Multivariate analyses showed no evident relation between MetS components and the level of physical activity. Conclusions Obese adults, mainly women, are particularly at risk of developing MetS, with the associated implications for their health. The increasing prevalence of MetS highlights the need for developing strategies for its early detection and prevention. PMID:25141255

Electricity supply opportunities -- The Mexican door opens

International Nuclear Information System (INIS)

Holland, H.W.

1993-01-01

Anyone who assumes that the Mexican market for electrical capacity is just a matter of selling equipment and services is in for a shock. The astute neighbor to the south is exploring privatization in the power sector with a style and flair that is uniquely Mexican. While free market-market forces have, to some extent, already transformed the manner in which new generating capacity is added in the US, a Mexico equivalent will not develop over night. Mexico is no place for the faint of heart. You have to play hard in order to win against competition almost equivalent to that of the US market and have the staying power to be around long enough to reap the rewards. This work presents the author's views concerning the manner in which competition has been introduced within the electricity supply market of the neighbor to the south

Identification of Bioactivity, Volatile and Fatty Acid Profile in Supercritical Fluid Extracts of Mexican arnica

Directory of Open Access Journals (Sweden)

J. Saúl García-Pérez

2016-09-01

Full Text Available Supercritical fluid extraction (SFE is a sustainable technique used for the extraction of lipophilic metabolites such as pigments and fatty acids. Arnica plant is considered a potential candidate material with high antioxidant and antimicrobial activities. Therefore, in this study, a locally available Heterotheca inuloides, also known as Mexican arnica, was analyzed for the extraction of high-value compounds. Based on different pressure (P, temperature (T, and co-solvent (CoS, four treatments (T were prepared. A maximum 7.13% yield was recovered from T2 (T = 60 °C, P = 10 MPa, CoS = 8 g/min, followed by 6.69% from T4 (T = 60 °C, P = 30 MPa, CoS = 4 g/min. Some bioactive sesquiterpenoids such as 7-hydroxycadalene, caryophyllene and δ-cadinene were identified in the extracts by GC/MS. The fatty acid profile revealed that the main components were palmitic acid (C16:0, followed by linoleic acid (C18:2ω6c, α-linolenic acid (C18:3ω3 and stearic acid (C18:0 differing in percent yield per treatment. Antibacterial activities were determined by the agar diffusion method, indicating that all the treatments exerted strong antibacterial activity against S. aureus, C. albicans, and E. coli strains. The antioxidant capacity of the extracts was also measured by three in vitro assays, DPPH, TEAC and FRAP, using Trolox as a standard. Results showed high antioxidant capacity enabling pharmaceutical applications of Mexican arnica.

NAFTA and the Mexican Economy

Science.gov (United States)

2008-11-04

its loans. Then President Miguel de la Madrid took steps to open and liberalize the Mexican economy and initiated procedures to replace import...capita income in countries. 24 Lessons from NAFTA, 2005. 25 Economia , “NAFTA and Convergence in North America: High Expectations, Big Events, Little Time...Easterly, Norbert Fiess, and Daniel Lederman, Economia , “NAFTA and Convergence in North America: High Expectations, Big Events, Little Time,” Fall 2003. The

Chemical Composition and Biological Activities of Fragrant Mexican Copal (Bursera spp.

Directory of Open Access Journals (Sweden)

Giulia Gigliarelli

2015-12-01

Full Text Available Copal is the Spanish word used to describe aromatic resins from several genera of plants. Mexican copal derives from several Bursera spp., Protium copal, some Pinus spp. (e.g., P. pseudostrobus and a few Fabaceae spp. It has been used for centuries as incense for religious ceremonies, as a food preservative, and as a treatment for several illnesses. The aim of this review is to analyze the chemical composition and biological activity of commercial Mexican Bursera copal.

Social support, stressors, and frailty among older Mexican American adults.

Science.gov (United States)

Peek, M Kristen; Howrey, Bret T; Ternent, Rafael Samper; Ray, Laura A; Ottenbacher, Kenneth J

2012-11-01

There is little research on the effects of stressors and social support on frailty. Older Mexican Americans, in particular, are at higher risk of medical conditions, such as diabetes, that could contribute to frailty. Given that the Mexican American population is rapidly growing in the United States, it is important to determine whether there are modifiable social factors related to frailty in this older group. To address the influence of social support and stressors on frailty among older Mexican Americans, we utilized five waves of the Hispanic Established Populations for the Epidemiologic Study of the Elderly (Hispanic EPESE) to examine the impact of stressors and social support on frailty over a 12-year period. Using a modified version of the Fried and Walston Frailty Index, we estimated the effects of social support and stressors on frailty over time using trajectory modeling (SAS 9.2, PROC TRAJ). We first grouped respondents according to one of three trajectories: low, progressive moderate, and progressive high frailty. Second, we found that the effects of stressors and social support on frailty varied by trajectory and by type of stressor. Health-related stressors and financial strain were related to increases in frailty over time, whereas social support was related to less-steep increases in frailty. Frailty has been hypothesized to reflect age-related physiological vulnerability to stressors, and the analyses presented indicate partial support for this hypothesis in an older sample of Mexican Americans. Future research needs to incorporate measures of stressors and social support in examining those who become frail, especially in minority populations.

Mexicans' use of illicit drugs in an era of drug reform: national comparative analysis by migrant status.

Science.gov (United States)

Guerrero, Erick G; Villatoro, Jorge Ameth; Kong, Yinfei; Gamiño, Marycarmen Bustos; Vega, William A; Mora, Maria Elena Medina

2014-05-01

Although rates of illicit drug use are considerably lower in Mexico than in the United States, rates in Mexico have risen significantly. This increase has particular implications for Mexican women and US migrants, who are considered at increased risk of drug use. Due to drug reforms enacted in Mexico in 2008, it is critical to evaluate patterns of drug use among migrants who reside in both regions. We analysed a sample of Mexicans (N=16,249) surveyed during a national household survey in 2011, the Encuesta Nacional de Adicciones (National Survey of Addictions). Comparative analyses based on Mexicans' migrant status - (1) never in the United States, (2) visited the United States, or (3) lived in the United States (transnationals) - featured analysis of variance and Chi-square global tests. Two multilevel regressions were conducted to determine the relationships among migrant status, women, and illicit drug use. Comparative findings showed significant differences in type and number of drugs used among Mexicans by migrant status. The regression models showed that compared with Mexicans who had never visited the United States, Mexican transnationals were more likely to report having used drugs (OR=2.453, 95% CI=1.933, 3.113) and using more illicit drugs (IRR=2.061, 95% CI=1.626, 2.613). Women were less likely than men to report having used drugs (OR=0.187, 95% CI=0.146, 0.239) and using more illicit drugs (IRR=0.153, 95% CI=0.116, 0.202). Overall, the findings support further exploration of risk factors for illicit drug use among Mexican transnationals, who exhibit greater drug use behaviours than Mexicans never in the United States. Because drug reform mandates referrals to treatment for those with recurrent issues of drug use, it is critical for the Mexican government and civic society to develop the capacity to offer evidence-based substance abuse treatment for returning migrants with high-risk drug behaviours. Copyright © 2014 Elsevier B.V. All rights reserved.

Partner effects of Mexican cultural values: the couple and parenting relationships.

Science.gov (United States)

Yu, Jeong Jin; Lucero-Liu, Ana A; Gamble, Wendy C; Taylor, Angela R; Christensen, Donna Hendrickson; Modry-Mandell, Kerri L

2008-03-01

In this investigation, the authors explored the impact of individuals' cultural values on their partners' relationship adjustment and perceptions of their parenting relationship. The authors examined Mexican cultural values of simpatía (i.e., harmonious interpersonal relationships) and respeto (i.e., respect for authority figures) using a sample of 50 Mexican-origin couples in southern Arizona. Congruent with their hypotheses, results supported the proposition that fathers' simpatía is positively associated with both relationship adjustment and the parenting relationship as reported by mothers, whereas fathers' respeto is negatively associated with both relationship adjustment and the parenting relationship as reported by mothers. However, the authors found little evidence of a contribution of mothers' cultural values to fathers' perceptions of either relationship adjustment or the parenting relationship. They interpret these findings to suggest that mothers' relationship adjustment and parenting relationship are more sensitive to and dependent on fathers' degree of traditional cultural values among Mexican-origin families.

Autonomy support, basic psychological needs and well-being in Mexican athletes.

Science.gov (United States)

López-Walle, Jeanette; Balaguer, Isabel; Castillo, Isabel; Tristán, José

2012-11-01

Based on Basic Needs Theory, one of the mini-theories of Self-determination Theory (Ryan & Deci, 2002), the present study had two objectives: (a) to test a model in the Mexican sport context based on the following sequence: perceived coach autonomy support, basic psychological needs satisfaction, and psychological well-being, and b) to analyze the mediational effect of the satisfaction of perceived coach autonomy support on indicators of psychological well-being (satisfaction with life and subjective vitality). Six hundred and sixty-nine young Mexican athletes (Boys = 339; Girls = 330; M(age) = 13.95) filled out a questionnaire assessing the study variables. Structural equations analyses revealed that perceived coach autonomy support predicted satisfaction of the basic psychological needs for autonomy, competence, and relatedness. Furthermore, basic need satisfaction predicted subjective vitality and satisfaction with life. Autonomy, competence and relatedness partially mediated the path from perceived coach autonomy support to psychological well-being in young Mexican athletes.

The Mexican-American and Dramatic Literature.

Science.gov (United States)

Serrano, Hector M.

In the area of the arts, the Mexican American has discovered a rich cultural heritage which gives him a strong sense of pride and a deep feeling of satisfaction. A new interest in the literature of Mexico and the Southwestern states of Texas, Arizona, New Mexico, Colorado, and California has started the Chicano people reading classic and modern…

Recent Increases in Intermarriage by Mexican American Males: Bexar County, Texas, from 1971 to 1980.

Science.gov (United States)

Valdez, Avelardo

1983-01-01

Consistent with previous decades, Mexican-American exogamy rates during the 1970s steadily increased. However, this increase was a result of a rise in outmarriage rates for Mexican-American males rather than females as was the case in the past. (Author)

United States versus Mexican Perceptions of the Impact of the North American Free Trade Agreement.

Science.gov (United States)

Nicholson, Joel D.; And Others

1994-01-01

Surveys U.S. and Mexican managerial attitudes concerning the impact of the North American Free Trade Agreement (NAFTA) process on the United States. Discusses differences in Mexican and U.S. attitudes concerning NAFTA and a number of socioeconomic concerns. (SR)

Atlas of Mexican Triatominae (Reduviidae: Hemiptera) and vector transmission of Chagas disease

Science.gov (United States)

Ramsey, Janine M; Peterson, A Townsend; Carmona-Castro, Oscar; Moo-Llanes, David A; Nakazawa, Yoshinori; Butrick, Morgan; Tun-Ku, Ezequiel; de la Cruz-Félix, Keynes; Ibarra-Cerdeña, Carlos N

2015-01-01

Chagas disease is one of the most important yet neglected parasitic diseases in Mexico and is transmitted by Triatominae. Nineteen of the 31 Mexican triatomine species have been consistently found to invade human houses and all have been found to be naturally infected with Trypanosoma cruzi. The present paper aims to produce a state-of-knowledge atlas of Mexican triatomines and analyse their geographic associations with T. cruzi, human demographics and landscape modification. Ecological niche models (ENMs) were constructed for the 19 species with more than 10 records in North America, as well as for T. cruzi. The 2010 Mexican national census and the 2007 National Forestry Inventory were used to analyse overlap patterns with ENMs. Niche breadth was greatest in species from the semiarid Nearctic Region, whereas species richness was associated with topographic heterogeneity in the Neotropical Region, particularly along the Pacific Coast. Three species, Triatoma longipennis, Triatoma mexicana and Triatoma barberi, overlapped with the greatest numbers of human communities, but these communities had the lowest rural/urban population ratios. Triatomine vectors have urbanised in most regions, demonstrating a high tolerance to human-modified habitats and broadened historical ranges, exposing more than 88% of the Mexican population and leaving few areas in Mexico without the potential for T. cruzi transmission. PMID:25993505

Atlas of Mexican Triatominae (Reduviidae: Hemiptera and vector transmission of Chagas disease

Directory of Open Access Journals (Sweden)

Janine M Ramsey

2015-05-01

Full Text Available Chagas disease is one of the most important yet neglected parasitic diseases in Mexico and is transmitted by Triatominae. Nineteen of the 31 Mexican triatomine species have been consistently found to invade human houses and all have been found to be naturally infected with Trypanosoma cruzi. The present paper aims to produce a state-of-knowledge atlas of Mexican triatomines and analyse their geographic associations with T. cruzi, human demographics and landscape modification. Ecological niche models (ENMs were constructed for the 19 species with more than 10 records in North America, as well as for T. cruzi. The 2010 Mexican national census and the 2007 National Forestry Inventory were used to analyse overlap patterns with ENMs. Niche breadth was greatest in species from the semiarid Nearctic Region, whereas species richness was associated with topographic heterogeneity in the Neotropical Region, particularly along the Pacific Coast. Three species, Triatoma longipennis, Triatoma mexicana and Triatoma barberi, overlapped with the greatest numbers of human communities, but these communities had the lowest rural/urban population ratios. Triatomine vectors have urbanised in most regions, demonstrating a high tolerance to human-modified habitats and broadened historical ranges, exposing more than 88% of the Mexican population and leaving few areas in Mexico without the potential for T. cruzi transmission.

Cultural and social determinants of health among indigenous Mexican migrants in the United States.

Science.gov (United States)

Lee, Junghee; Donlan, William; Cardoso, Edgar Ezequiel Orea; Paz, Juan Jesus

2013-01-01

Despite growing numbers, indigenous Mexican migrants are relatively invisible to health practitioners who group them with nonindigenous, mestizo Mexican-origin populations. Associations between indigenous and mestizo cultural identifications with psychosocial characteristics and health indicators among indigenous Mexican migrants were examined. Results revealed gender differences in cultural identifications, perceived discrimination, self-esteem, self-efficacy, and various health indicators including depression severity, culture-bound syndromes, and self-rated health. Multivariate regression and structural equation path modeling demonstrated how indigenous cultural identification and perceived discrimination affects health. Findings suggest that interventions should utilize indigenous community-based activities designed to promote self-esteem and the value of indigenous culture, with a focus on females.

Prayer to the Saints or the Virgin and Health among Older Mexican Americans

Science.gov (United States)

Krause, Neal; Bastida, Elena

2011-01-01

The purpose of this study was to evaluate a conceptual model that assesses whether praying to the saints or the Virgin is associated with the health of older Mexican Americans. A survey was conducted of 1,005 older Mexican Americans (Mean age = 73.9 years; SD = 6.6 years). Data from 795 of the Catholic respondents are presented in this study. The…

Global trade in environmental goods and services Performance and Challenges of Mexican Industry

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René Lara

2017-11-01

Full Text Available This article studies the environmental industries of Mexico and the United States Within the framework of the North American Free Trade NAFTA, where Mexican industry lags behind lack of funds due to recurring economic crises. Should this situation not be overcome, the benefits of foreign trade for the Mexican environmental industry will remain low.

Mexican-Origin Youth's Cultural Orientations and Adjustment: Changes from Early to Late Adolescence

Science.gov (United States)

Updegraff, Kimberly A.; Umaña-Taylor, Adriana J.; McHale, Susan M.; Wheeler, Lorey A.; Perez-Brena, Norma

2013-01-01

Drawing from developmental and cultural adaptation perspectives and using a longitudinal design, this study examined: (a) mean-level changes in Mexican-origin adolescents’ cultural orientations and adjustment from early to late adolescence; and (b) bidirectional associations between cultural orientations and adjustment using a cross-lag panel model. Participants included 246 Mexican-origin, predominantly immigrant families that participated in home interviews and a series of nightly phone calls when target adolescents were 12 years and 18 years of age. Girls exhibited more pronounced declines in traditional gender role attitudes than did boys, and all youth declined in familism values, time spent with family, and involvement in Mexican culture. Bidirectional relations between cultural orientations and adjustment emerged, and some associations were moderated by adolescent nativity and gender. PMID:22966929

A Biopsychosocial Approach to Examine Mexican American Adolescents’ Academic Achievement and Substance Use

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Yang Qu

2018-04-01

Full Text Available Taking a comprehensive biopsychosocial approach and using a two-wave longitudinal design, this study examines the relation between brain development and the social environment in Mexican American youth’s (N = 41.56 percent female academic achievement and substance use. We find that both Mexican American youth’s structural brain development and social environment uniquely contribute to their adjustment. Specially, smaller hippocampal volume and parental cultural socialization each uniquely predict better academic achievement. Moreover, smaller nucleus accumbens volume and less affiliation with deviant peers each uniquely predict less substance use. These findings underscore the independent contributions of biological and psychosocial factors in youth’s adjustment. The study provides a new biopsychosocial perspective on Mexican American youth’s well-being.

New offshore platform in the Mexican Gulf

Energy Technology Data Exchange (ETDEWEB)

Beisel, T.

1982-04-01

After a construction period of only 10 months, the second steel Offshore platform was recently completed in the Mexican Gulf. The pattern for this structure was the Cognac platform. The erection of the new platform, called the 'Cerveza' platform, is described in the article.

Second Mexican School of Nuclear Physics: Notes

International Nuclear Information System (INIS)

Aguilera, E.F.; Chavez L, E.R.; Hess, P.O.

2001-01-01

The II Mexican School of Nuclear Physics which is directed to those last semesters students of the Physics career or post-graduate was organized by the Nuclear Physics Division of the Mexican Physics Society, carrying out at April 16-27, 2001 in the installations of the Institute of Physics and the Institute of Nuclear Sciences, both in the UNAM, and the National Institute of Nuclear Research (ININ). A first school of a similar level in Nuclear Physics, was carried out in Mexico at 1977 as Latin american School of Physics. This book treats about the following themes: Interactions of radiation with matter, Evaluation of uncertainty in experimental data, Particle accelerators, Notions of radiological protection and dosimetry, Cosmic rays, Basis radiation (environmental), Measurement of excitation functions with thick targets and inverse kinematics, Gamma ray technique for to measure the nuclear fusion, Neutron detection with Bonner spectrometer, Energy losses of alpha particles in nickel. It was held the practice Radiation detectors. (Author)

38 CFR 3.252 - Annual income; pension; Mexican border period and later war periods.

Science.gov (United States)

2010-07-01

...; Mexican border period and later war periods. 3.252 Section 3.252 Pensions, Bonuses, and Veterans' Relief... Dependency, Income and Estate § 3.252 Annual income; pension; Mexican border period and later war periods. (a) Annual income limitations; old-law pension. Where the right to old-law pension is payable under section...

Socioeconomic status and organ damage in Mexican systemic lupus erythematosus women.

Science.gov (United States)

Mendoza-Pinto, C; Méndez-Martínez, S; Soto-Santillán, P; Galindo Herrera, J; Pérez-Contreras, I; Macías-Díaz, S; Taboada-Cole, A; García-Carrasco, M

2015-10-01

The objective of this cross-sectional study was to determine relationships between socioeconomic status and organ damage in Mexican systemic lupus erythematosus (SLE) patients. Demographic and clinical variables were assessed. Socioeconomic status was evaluated using the Graffar method and monthly household income. Lupus activity and organ damage were measured using the SLE disease activity scale, validated for the Mexican population (Mex-SLEDAI), and the Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) scale. The 143 Mexican female SLE patients included (mean age 40.1 ± 8.9 years, mean disease duration 8.9 ± 6.3 years) had a mean monthly household income of $ 407.2 ± 326.5. According to the Graffar index, 18.9%, 52.5%, and 28.7% had high/medium-high, medium, and medium-low/low socioeconomic status, respectively. Organ damage was observed in 61 patients (42.7%). Patients with organ damage had lower monthly household incomes ($241.4 ± 152.4 vs. $354.8 ± 288.3) and were more frequently unemployed (57.3% vs. 35.3%; p = 0.01) than those without. Low monthly income was not associated with lupus activity or self-reported health status. In the adjusted multivariate analysis, low monthly income ( < $300) was associated with organ damage. In conclusion, low income may be associated with organ damage in Mexican SLE patients. © The Author(s) 2015.

Civic Engagement Patterns of Undocumented Mexican Students

Science.gov (United States)

Perez, William; Espinoza, Roberta; Ramos, Karina; Coronado, Heidi; Cortes, Richard

2010-01-01

This study examined the civic engagement of undocumented Mexican students. Civic engagement was defined as providing a social service, activism, tutoring, and functionary work. Survey data results (n = 126) suggest that despite high feelings of rejection because of their undocumented status, part-time employment, and household responsibilities,…

Weight Preoccupation in Female Mexican American Adolescents.

Science.gov (United States)

Guinn, Bobby; Jorgensen, Layne; Semper, Tom; Vincent, Vern

2002-01-01

Investigated the contribution of body size, self-esteem, age, mainstream acculturation, and athletic status to concern or preoccupation about weight among female Mexican American adolescents. Students had low acculturation, high body fatness, and moderate self-esteem. There was little difference between athletes and non-athletes. Greater body size…

Mexican-origin parents' work conditions and adolescents' adjustment.

Science.gov (United States)

Wheeler, Lorey A; Updegraff, Kimberly A; Crouter, Ann

2015-06-01

Mexican-origin parents' work experiences are a distal extrafamilial context for adolescents' adjustment. This 2-wave multiinformant study examined the prospective mechanisms linking parents' work conditions (i.e., self-direction, work pressure, workplace discrimination) to adolescents' adjustment (i.e., educational expectations, depressive symptoms, risky behavior) across the transition to high school drawing on work socialization and spillover models. We examined the indirect effects of parental work conditions on adolescent adjustment through parents' psychological functioning (i.e., depressive symptoms, role overload) and aspects of the parent-adolescent relationship (i.e., parental solicitation, parent-adolescent conflict), as well as moderation by adolescent gender. Participants were 246 predominantly immigrant, Mexican-origin, 2-parent families who participated in home interviews when adolescents were approximately 13 and 15 years of age. Results supported the positive impact of fathers' occupational self-direction on all 3 aspects of adolescents' adjustment through decreased father-adolescent conflict, after controlling for family socioeconomic status and earner status, and underemployment. Parental work pressure and discrimination were indirectly linked to adolescents' adjustment, with different mechanisms emerging for mothers and fathers. Adolescents' gender moderated the associations between fathers' self-direction and girls' depressive symptoms, and fathers' experiences of discrimination and boys' risk behavior. Results suggest that Mexican-origin mothers' and fathers' perceptions of work conditions have important implications for multiple domains of adolescents' adjustment across the transition to high school. (c) 2015 APA, all rights reserved).

Historical, Socio-Cultural, and Conceptual Issues to Consider When Researching Mexican American Children and Families, and other Latino Subgroups

Directory of Open Access Journals (Sweden)

Raymond Buriel

2012-12-01

Full Text Available In order for the field of psychology in the United States to maintain its relevance and validity, it must become more inclusive in its theory and research of Latinos, who are now the largest "minority" group in the nation. In particular, due to immigration and birth rates, Mexican Americans are the largest and fastest growing segment of the Latino population. This paper addresses some of the most significant historical and socio-cultural factors contributing to the psychological nature and wellbeing of Mexican Americans. These factors should be understood and used to guide research and theory in order to make the discipline of psychology relevant for Mexican Americans. The concept of mestizaje is used to explain the biological and cultural mixing constituting the diverse origins of the Mexican people. Immigration to the U.S. is described in terms of selective socio-cultural variables giving rise to a diverse Mexican American culture that is resistant to complete assimilation. Within a U.S. context, the constructs of generational status, acculturation, and biculturalism are used to explain the socio-cultural adaptation of Mexican Americans. The special role of children in immigrant families as language and cultural brokers are also discussed, and used to explain the adjustment of Mexican American families.

[To what extent is Mexican emigration to the United States a brain drain?].

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Osborn, T N; Newton, J R

1979-01-01

The authors examine the problem of legal Mexican emigration to the United States, analyzing its effects on both countries. Characteristics of the Mexican emigrants are examined with respect to level of employment, salary, and employment opportunities. The total number of emigrants in professional and technical capacities is investigated in order to determine the likelihood of a brain drain from Mexico to the United States

Genome-wide analysis of SNPs is consistent with no domestic dog ancestry in the endangered Mexican Wolf (Canis lupus baileyi)

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Fitak, Robert R.; Rinkevich, Sarah E.; Culver, Melanie

2018-01-01

The Mexican gray wolf (Canis lupus baileyi) was historically distributed throughout the southwestern United States and northern Mexico. Extensive predator removal campaigns during the early 20th century, however, resulted in its eventual extirpation by the mid 1980s. At this time, the Mexican wolf existed only in 3 separate captive lineages (McBride, Ghost Ranch, and Aragón) descended from 3, 2, and 2 founders, respectively. These lineages were merged in 1995 to increase the available genetic variation, and Mexican wolves were reintroduced into Arizona and New Mexico in 1998. Despite the ongoing management of the Mexican wolf population, it has been suggested that a proportion of the Mexican wolf ancestry may be recently derived from hybridization with domestic dogs. In this study, we genotyped 87 Mexican wolves, including individuals from all 3 captive lineages and cross-lineage wolves, for more than 172000 single nucleotide polymorphisms. We identified levels of genetic variation consistent with the pedigree record and effects of genetic rescue. To identify the potential to detect hybridization with domestic dogs, we compared our Mexican wolf genotypes with those from studies of domestic dogs and other gray wolves. The proportion of Mexican wolf ancestry assigned to domestic dogs was only between 0.06% (SD 0.23%) and 7.8% (SD 1.0%) for global and local ancestry estimates, respectively; and was consistent with simulated levels of incomplete lineage sorting. Overall, our results suggested that Mexican wolves lack biologically significant ancestry with dogs and have useful implications for the conservation and management of this endangered wolf subspecies.

The Effects of Parental Acculturation and Parenting Practices on the Substance Use of Mexican-Heritage Adolescents from Southwestern Mexican Neighborhoods

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MARSIGLIA, FLAVIO F.; NAGOSHI, JULIE L.; PARSAI, MONICA; CASTRO, FELIPE GONZÁLEZ

2014-01-01

A sample of 189 Mexican-heritage seventh grade adolescents reported their substance use, while one of the child’s parents reported parent’s acculturation and communication, involvement, and positive parenting with his or her child. Higher levels of parental acculturation predicted greater marijuana use, whereas parent communication predicted lower cigarette and marijuana use among girls. A significant parent acculturation by parent communication interaction for cigarette use was due to parent communication being highly negatively associated with marijuana use for high acculturated parents, with attenuated effects for low acculturated parents. A significant child gender by parent acculturation by parent positive parenting interaction was found. For girls, positive parenting had a stronger association with lower cigarette use for high acculturated parents. For boys, positive parenting had a stronger association with reduced cigarette use for low acculturated parents. Discussion focuses on how acculturation and gender impact family processes among Mexican-heritage adolescents. PMID:25176121

75 FR 24741 - Endangered and Threatened Wildlife and Plants; Mexican Wolf (Canis lupus baileyi) Conservation...

Science.gov (United States)

2010-05-05

...] Endangered and Threatened Wildlife and Plants; Mexican Wolf (Canis lupus baileyi) Conservation Assessment... Mexico Ecological Services Field Office, 2105 Osuna NE, Albuquerque, NM 87113; by telephone at 505-761... guided by the 1982 Mexican Wolf Recovery Plan (U.S. Fish and Wildlife Service 1982) (recovery plan...

Current floristic and phytogeographic knowledge of Mexican Bromeliaceae

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Adolfo Espejo Serna

1998-09-01

Full Text Available A current floristic and phytogeographic knowledge of native Mexican Bromeliaceae is presented. There are 22 genera of Bromeliaceae recorded from the country that include 326 species. The genus Ursulaea with 2 species is endemic to Mexico, while Hechtia with 48 of its 50 species has its principal center of diversity in the country. Tillandsia (175 spp, Hechtia (48 spp and Pitcairnia (46 spp are the genera with the greatest number of species. We present a comparative analysis of Mexican Bromeliaceae with that of other American regions that have recently published accounts for the Family, particularly the Mesomerican area, Venezuela, Ecuador, and the Guianas. Our results led us to the conclusion that all these floras should be considered as distinct. We observe a progressive decrease of the Simpson index value related with the remoteness of the Mexican area. A general analysis of the species numbers of Mexican bromeliad genera shows a distinct preference of the species for coniferous and oak forests, followed by tropical caducifolious forests. There is also significant representation of the family in other vegetation types such as cloud forests and tropical perennifolious forests. Generally Mexican Bromeliaceae species have scarce and sparse populations and in many cases they inhabit cliffs, bluffs and scarps in restricted areas. Concerning the geographic distribution of Mexican genera, 77.27 % are neotropical, 4.54% are South American and the remainder are Mexican and Central American. The generic endemism is very low (4.54 %, even if we extend the country limits to Megamexico sensu Rzedowsi (1991 it reaches only 13.63 %. The family endemism at specific level reaches 63.07 %. There are not available data about a specific analysis of the conservation status of Mexican Bromeliaceae, but we can point out that a great number of taxa are only known from the type collection or at the most from the type locality. This can perhaps be attributed in part to

Thermal-Diffusivity Measurements of Mexican Citrus Essential Oils Using Photoacoustic Methodology in the Transmission Configuration

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Muñoz, G. A. López; González, R. F. López; López, J. A. Balderas; Martínez-Pérez, L.

2011-05-01

Photoacoustic methodology in the transmission configuration (PMTC) was used to study the thermophysical properties and their relation with the composition in Mexican citrus essential oils providing the viability of using photothermal techniques for quality control and for authentication of oils and their adulteration. Linear relations for the amplitude (on a semi-log scale) and phase, as functions of the sample's thickness, for the PMTC was obtained through a theoretical model fit to the experimental data for thermal-diffusivity measurements in Mexican orange, pink grapefruit, mandarin, lime type A, centrifuged essential oils, and Mexican distilled lime essential oil. Gas chromatography for distilled lime essential oil and centrifuged lime essential oil type A is reported to complement the study. Experimental results showed close thermal-diffusivity values between Mexican citrus essential oils obtained by centrifugation, but a significant difference of this physical property for distilled lime oil and the corresponding value obtained by centrifugation, which is due to their different chemical compositions involved with the extraction processes.

The Need to Remove the Civil Code from Mexican Commercial Laws: The Case of “Offers” and “Firm Promises”

OpenAIRE

Iturralde González, Raúl

2017-01-01

Abstract: In 1889, then Mexican President Porfirio Díaz enacted the Mexican Commercial Code that is still in force today. This code was inspired on the Napoleonic code of 1807. Unfortunately, the Mexican code eliminated the use of commercial customs and practices as an accepted method for breaching gaps in commercial law. Since then, Mexican commercial law has held the civil code as the basis for dealing with gaps and loopholes in the application of commercial law. This has prevented the furt...

Towards an Informed Mexican and Mexican-American Citizenry: Bridging the Gap to Increase Human Capacity and Information Dissemination

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Ramirez, M. D.; Ramirez, D. M.

2008-12-01

The research translation and community outreach goal of The University of Arizona's (UA) Superfund Basic Research Program and U.S.-Mexico Binational Center for Environmental Sciences and Toxicology is to increase human capacity and information dissemination to diverse stakeholders, including federal, state, and local government agencies as well as northern Mexican and border community stakeholders. Due to Arizona's demographic characteristics and the UA's proximity to the U.S. - Mexico border, activities target primarily Mexican and Mexican-American populations. With this in mind, a model has been established that pulls from human capital, community-based participatory research and public participation theories. The theories applied to our target population have resulted in the creation of a successful model that is used in both research translation and community outreach work. The model contains four components: community needs (participation), science translation (information), engagement (outreach), and training (education). Examples of how this model operates for various stakeholders involved in environmental science and health issues will be discussed. A case in point of how this model has been applied effectively is the partnership with promotoras (community health advocates) to do environmental science and health trainings to increase the knowledge base of specific populations disproportionately exposed to contaminants of concern. Additional case studies and methodologies used to develop innovative communicative tools (that takes into consideration cultural idiosyncrasies) for stakeholders at all levels in Arizona, the border, and Mexico will be highlighted, such as: 1) information sheets regarding local environmental issues for communities neighboring contaminated sites, 2) SciTransfer Bulletins targeting professional level stakeholders such as Project Managers, Community Involvement Coordinators and the general public, 3) coordinating technical and

The influence of an estimated energy saving due to natural ventilation on the Mexican energy system

DEFF Research Database (Denmark)

Oropeza-Perez, Ivan; Østergaard, Poul Alberg

2014-01-01

This article shows the impacts of the extensive use of NV (natural ventilation) in the Mexican residential sector on the Mexican energy system. By integrating a thermal-airflow simulation programme with an energy systems analysis model, the impact on the Mexican energy system of replacing air...... conditioning, in particular, with natural ventilation to cool residential buildings is determined. It is shown that when, as in Mexico, there is a relatively simple connection between supply and electricity demand, NV creates savings which could be used to reduce either the fossil-fuel-based generation...

Using a Positive Psychology and Family Framework to Understand Mexican American Adolescents' College-Going Beliefs

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Vela, Javier C.; Lenz, A. Stephen; Sparrow, Gregory Scott; Gonzalez, Stacey Lee

2017-01-01

Positive psychology is a useful framework to understand Mexican American adolescents' academic experiences. We used a quantitative, predictive design to explore how presence of meaning in life, search for meaning in life, subjective happiness, hope, and family importance influenced 131 Mexican American adolescents' college-going beliefs. We used…

Study protocol: intervention in maternal perception of preschoolers' weight among Mexican and Mexican-American mothers.

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Flores-Peña, Yolanda; He, Meizi; Sosa, Erica T; Avila-Alpirez, Hermelinda; Trejo-Ortiz, Perla M

2018-05-30

Childhood obesity is a public health issue negatively affecting children's physical and psychosocial health. Mothers are children's primary caregivers, thus key players in childhood obesity prevention. Studies have indicated that mothers underestimate their children's weight. If mothers are unaware of their children's weight problem, they are less likely to participate in activities preventing and treating excess weight. The "Healthy Change" intervention is designed to change maternal perception of child's weight (MPCW) through peer-led group health education in childcare settings. The "Healthy Change" is a multicenter two-arm randomized trial in four centers. Three centers are in Mexican States (Nuevo Leon, Tamaulipas, and Zacatecas). The fourth center is in San Antonio, Texas, USA. A total of 360 mother-child pairs (90 pairs per center) are to be randomly and evenly allocated to either the intervention or the control group. Intervention group will receive four-session group obesity prevention education. Control group will receive a four-session personal and food hygiene education. The education is delivered by trained peer-mother promotoras. Data will be collected using questionnaires and focus groups. The primary outcome is a change in proportion of mothers with accurate MPCW. Secondary outcomes include change in maternal feeding styles and practices, maternal self-efficacy and actions for managing child excessive weight gain. McNemar's Test will be used to test the primary outcome. The GLM Univariate procedure will be used to determine intervention effects on secondary outcomes. The models will include the secondary outcome measures as the dependent variables, treatment condition (intervention/control) as the fixed factor, and confounding factors (e.g., mother's education, children's gender and age) as covariates. Sub-analyses will be performed to compare intervention effects on primary and secondary outcomes between the samples from Mexico and Texas, USA

Reflective Polyethylene Mulch Reduces Mexican Bean Beetle (Coleoptera: Coccinellidae) Densities and Damage in Snap Beans.

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Nottingham, L B; Kuhar, T P

2016-08-01

Mexican bean beetle, Epilachna varivestis Mulsant, is a serious pest of snap beans, Phaseolus vulgaris L., in the eastern United States. These beetles are intolerant to direct sunlight, explaining why individuals are typically found on the undersides of leaves and in the lower portion of the plant canopy. We hypothesized that snap beans grown on reflective, agricultural polyethylene (plastic mulch) would have fewer Mexican bean beetles and less injury than those grown on black plastic or bare soil. In 2014 and 2015, beans were seeded into beds of metallized, white, and black plastic, and bare soil, in field plots near Blacksburg, VA. Mexican bean beetle density, feeding injury, predatory arthropods, and snap bean yield were sampled. Reflected light intensity, temperature, and humidity were monitored using data loggers. Pyranometer readings showed that reflected light intensity was highest over metallized plastic and second highest over white plastic; black plastic and bare soil were similarly low. Temperature and humidity were unaffected by treatments. Significant reductions in Mexican bean beetle densities and feeding injury were observed in both metallized and white plastic plots compared to black plastic and bare soil, with metallized plastic having the fewest Mexican bean beetle life stages and injury. Predatory arthropod densities were not reduced by reflective plastic. Metallized plots produced the highest yields, followed by white. The results of this study suggest that growing snap beans on reflective plastic mulch can suppress the incidence and damage of Mexican bean beetle, and increase yield in snap beans. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Update of the Mexican College of Rheumatology guidelines for the pharmacologic treatment of rheumatoid arthritis.

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Cardiel, Mario H; Díaz-Borjón, Alejandro; Vázquez del Mercado Espinosa, Mónica; Gámez-Nava, Jorge Iván; Barile Fabris, Leonor A; Pacheco Tena, César; Silveira Torre, Luis H; Pascual Ramos, Virginia; Goycochea Robles, María Victoria; Aguilar Arreola, Jorge Enrique; González Díaz, Verónica; Alvarez Nemegyei, José; González-López, Laura del Carmen; Salazar Páramo, Mario; Portela Hernández, Margarita; Castro Colín, Zully; Xibillé Friedman, Daniel Xavier; Alvarez Hernández, Everardo; Casasola Vargas, Julio; Cortés Hernández, Miguel; Flores-Alvarado, Diana E; Martínez Martínez, Laura A; Vega-Morales, David; Flores-Suárez, Luis Felipe; Medrano Ramírez, Gabriel; Barrera Cruz, Antonio; García González, Adolfo; López López, Susana Marisela; Rosete Reyes, Alejandra; Espinosa Morales, Rolando

2014-01-01

The pharmacologic management of rheumatoid arthritis has progressed substantially over the past years. It is therefore desirable that existing information be periodically updated. There are several published international guidelines for the treatment of rheumatoid arthritis that hardly adapt to the Mexican health system because of its limited healthcare resources. Hence, it is imperative to unify the existing recommendations and to incorporate them to a set of clinical, updated recommendations; the Mexican College of Rheumatology developed these recommendations in order to offer an integral management approach of rheumatoid arthritis according to the resources of the Mexican health system. To review, update and improve the available evidence within clinical practice guidelines on the pharmacological management of rheumatoid arthritis and produce a set of recommendations adapted to the Mexican health system, according to evidence available through December 2012. The working group was composed of 30 trained and experienced rheumatologists with a high quality of clinical knowledge and judgment. Recommendations were based on the highest quality evidence from the previously established treatment guidelines, meta-analysis and controlled clinical trials for the adult population with rheumatoid arthritis. During the conformation of this document, each working group settled the existing evidence from the different topics according to their experience. Finally, all the evidence and decisions were unified into a single document, treatment algorithm and drug standardization tables. This update of the Mexican Guidelines for the Pharmacologic Treatment of Rheumatoid Arthritis provides the highest quality information available at the time the working group undertook this review and contextualizes its use for the complex Mexican health system. Copyright © 2013 Elsevier España, S.L. All rights reserved.

Program of active aging in a rural Mexican community: a qualitative approach

OpenAIRE

Mendoza-Núñez Víctor; Correa-Muñoz Elsa; de la Luz Martínez-Maldonado María

2007-01-01

Abstract Background Education is one of the key elements in the promotion of a thorough paradigm for active aging. The aim of this study is to analyze factors that contribute the empowerment of older adults in a rural Mexican community and, thus, promote active aging. Methods The study was conducted in a rural Mexican community (Valle del Mezquital), based on an action-research paradigm. One hundred and fifty-five elderly subjects with elementary school education participated in a formal trai...

Implicit Race/Ethnic Prejudice in Mexican Americans

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Garza, Christelle Fabiola; Gasquoine, Philip Gerard

2013-01-01

Implicit race/ethnic prejudice was assessed using Spanish- and English-language versions of an Implicit Association Test that used Hispanic/Anglo first names and pleasant/unpleasant words as stimuli. This test was administered to a consecutive sample of Mexican American adults residing in the Rio Grande Valley region of Texas of whom about…

Reproductive rights violations reported by Mexican women with HIV.

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Kendall, Tamil

2009-01-01

Demand for reproductive health services by people with HIV is increasing, as is the urgency of protecting and promoting their reproductive rights. The reproductive rights of Mexicans with HIV are formally protected by the constitution and by health and anti-discrimination legislation, as well as by international conventions. However, the reproductive rights of women with HIV continue to be violated in public clinics and hospitals. This paper discusses three violations identified as priority problems by Mexican women with HIV, illustrating these problems with cases identified during a participatory skills building workshop. The violations cover the following rights: the right to non-discrimination, the right to adequate information and informed consent to medical procedures, and the right to choose the number and spacing of children. Physicians can either violate or promote reproductive rights. Unfortunately, in many instances Mexican physicians continue to perpetrate reproductive rights abuses against women with HIV. Collaborations between women with HIV, civil society, government, and international organizations are needed to educate and sanction health care providers and to support women with HIV in their pursuit of reproductive rights. Demanding accountability from health care practitioners and the State to guarantee reproductive rights in countries where these rights are formally protected will improve the quality of life of people with HIV and can demonstrate that rights-based approaches are compatible with and indeed, crucial for public health.

Perceived parental psychological control, familism values, and Mexican American college students' adjustment.

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Kline, Gabrielle C; Killoren, Sarah E; Alfaro, Edna C

2016-10-01

Drawing from cultural ecological and risk and resilience perspectives, we investigated associations among Mexican American college students' perceptions of mothers' and fathers' psychological control and familism values, and college students' adjustment (i.e., depressive symptoms and self-esteem). Additionally, we examined how familism values moderated the relations between perceived psychological control and college students' adjustment. Participants were 186 Mexican American college students (78.5% women; Mage = 21.56 years), and data were collected using self-report online surveys. Using path analyses, we found that perceived maternal psychological control was positively associated and familism values were negatively associated with college students' depressive symptoms. Additionally, perceived paternal psychological control was negatively associated with college students' self-esteem when college students reported low, but not high, familism values. Findings highlight the importance of family relationships for Mexican American college students and the significance of examining these relationships within this cultural context. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

School Context and the Effect ESL Placement on Mexican-Origin Adolescents' Achievement.

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Callahan, Rebecca; Wilkinson, Lindsey; Muller, Chandra

2008-01-01

OBJECTIVES: Immigrant adolescents' academic achievement is crucial to our future economic stability, and Mexican-origin linguistic minority youth in U.S. schools generally demonstrate lower levels of achievement. English as a Second Language (ESL) programs provide an institutional response to these students' needs, the effect of which may vary by the proportion of immigrant students in the school. MEASURES: Using propensity score matching and data from the Adolescent Health and Academic Achievement Study (AHAA) and the National Longitudinal Study of Adolescent Health (Add Health), we estimate the effect of ESL placement on Mexican-origin achievement for first-, second-, and third-generation adolescents separately in schools with many and few immigrant students. RESULTS: The estimated effect of ESL placement varies by both immigrant concentration in the school and by students' generational status. CONCLUSIONS: We find that ESL enrollment may be protective for second-generation Mexican-origin adolescents in high immigrant concentration schools, and may prove detrimental for first-generation adolescents in contexts with few other immigrant students.

Food-associated lactic acid bacteria with antimicrobial potential from traditional Mexican foods.

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Alvarado, C; García Almendárez, B E; Martin, S E; Regalado, C

2006-01-01

This work was conducted to identify indigenous LAB capable of antimicrobial activity, present in traditional Mexican-foods with potential as natural preservatives. A total of 27 artisan unlabeled Mexican products were evaluated, from which 94 LAB strains were isolated, and only 25 strains showed antimicrobial activity against at least one pathogen indicator microorganism. Most of the inhibitory activity showed by the isolated LAB strains was attributed to pH reduction by organic acids. Lactobacillus and Lactococcus strains were good acid producers, depending on the substrate, and may enhance the safety of food products. Cell free cultures of Leuconostoc mesenteroides CH210, and PT8 (from chorizo and pulque, respectively) reduced the number of viable cells of enteropathogenic E. coli in broth system. Lb. plantarum CC10 (from "madre" of vinegar) showed significant inhibitory effect against S. aureus 8943. E. faecium QPII (from panela cheese) produced a bacteriocin with wide anti-L. monocytogenes activity. Selected LAB from traditional Mexican foods showed good potential as bio-preservatives.

Generational Patterns in Mexican Americans' Academic Performance in an Unwelcoming Political Context

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Moosmann, Danyel A. V.; Roosa, Mark W.; Knight, George P.

2014-01-01

Research has shown that immigrant students often do better academically than their U.S.-born peers from the same ethnic group but it is unclear whether this pattern holds for Mexican Americans. We examined the academic performance of four generations of Mexican American students from fifth to 10th grade looking for generation differences and explanations for them. Using data from 749 families, we tested a model with fifth grade variables that differed by generation as potential mediators linking student generation to 10th grade academic performance. Results showed that immigrants were academically behind at fifth grade but caught up by seventh. Only economic hardship mediated the long term relationship between student generation and 10th grade academic performance; maternal educational expectations and child language hassles, English usage, discrimination, and mainstream values helped explained the early academic deficit of immigrant children. The results identified potential targets for interventions to improve Mexican American students' academic performance. PMID:24578588

Long term natural gas supply in North America: prospects for mexican exports

International Nuclear Information System (INIS)

Elizalde Baltierra, A.

1999-01-01

The aim of this work is to discuss the most important factors and uncertainties likely to affect future Mexican natural gas exports to the United States. Firstly, we study the long term natural gas supply/demand balance in North America over the period from 2000 to 2020. Secondly, we analyze the main driving forces determining future natural gas supply and demand in Mexico, which also allows us to discuss the prospects for Mexican gas exports. Finally, our analysis suggests that: in the short and medium term (2000-2010), Mexico will probably continue to increase imports of USA gas in order to satisfy increasing demand and will probably not export large volumes of gas to the USA; in the long term (2020-2020), Mexico could resume exports to the USA in sizeable quantities. Two main conditions appear necessary to resume exports: Premex's budgetary constraints should be relaxed and/or new foreign investment should be able to participate in the Mexican upstream oil and gas sector. (author)

A statistical assessment of population trends for data deficient Mexican amphibians

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Esther Quintero

2014-12-01

Full Text Available Background. Mexico has the world’s fifth largest population of amphibians and the second country with the highest quantity of threatened amphibian species. About 10% of Mexican amphibians lack enough data to be assigned to a risk category by the IUCN, so in this paper we want to test a statistical tool that, in the absence of specific demographic data, can assess a species’ risk of extinction, population trend, and to better understand which variables increase their vulnerability. Recent studies have demonstrated that the risk of species decline depends on extrinsic and intrinsic traits, thus including both of them for assessing extinction might render more accurate assessment of threats.Methods. We harvested data from the Encyclopedia of Life (EOL and the published literature for Mexican amphibians, and used these data to assess the population trend of some of the Mexican species that have been assigned to the Data Deficient category of the IUCN using Random Forests, a Machine Learning method that gives a prediction of complex processes and identifies the most important variables that account for the predictions.Results. Our results show that most of the data deficient Mexican amphibians that we used have decreasing population trends. We found that Random Forests is a solid way to identify species with decreasing population trends when no demographic data is available. Moreover, we point to the most important variables that make species more vulnerable for extinction. This exercise is a very valuable first step in assigning conservation priorities for poorly known species.

A statistical assessment of population trends for data deficient Mexican amphibians.

Science.gov (United States)

Quintero, Esther; Thessen, Anne E; Arias-Caballero, Paulina; Ayala-Orozco, Bárbara

2014-01-01

Background. Mexico has the world's fifth largest population of amphibians and the second country with the highest quantity of threatened amphibian species. About 10% of Mexican amphibians lack enough data to be assigned to a risk category by the IUCN, so in this paper we want to test a statistical tool that, in the absence of specific demographic data, can assess a species' risk of extinction, population trend, and to better understand which variables increase their vulnerability. Recent studies have demonstrated that the risk of species decline depends on extrinsic and intrinsic traits, thus including both of them for assessing extinction might render more accurate assessment of threats. Methods. We harvested data from the Encyclopedia of Life (EOL) and the published literature for Mexican amphibians, and used these data to assess the population trend of some of the Mexican species that have been assigned to the Data Deficient category of the IUCN using Random Forests, a Machine Learning method that gives a prediction of complex processes and identifies the most important variables that account for the predictions. Results. Our results show that most of the data deficient Mexican amphibians that we used have decreasing population trends. We found that Random Forests is a solid way to identify species with decreasing population trends when no demographic data is available. Moreover, we point to the most important variables that make species more vulnerable for extinction. This exercise is a very valuable first step in assigning conservation priorities for poorly known species.

Education in a Global Era: Exploring the Impact of Global Economic Exchanges on Mexican Education.

Science.gov (United States)

Hampton, Elaine

A study examined the changes created in Mexican education resulting from the North American Free Trade Agreement and the hundreds of foreign (mostly U.S.) manufacturing operations, or maquiladoras, benefitting from the agreement. Interview data from 100 Mexicans and 25 schools indicate that the maquiladoras provide jobs for people who had none,…

Mexican Origin Students in the Borderlands: The Construction of Social Identity in the School Context

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Villarreal Sosa, Leticia

2011-01-01

There has been continued concern over the continued high dropout rate among Mexican origin youth. The purpose of this study is to understand how everyday experiences in school shape the content and meaning of Mexican origin students' social identities and how those social identities influence their academic trajectories over the transition to…

Pubertal Timing and Mexican-Origin Girls' Internalizing and Externalizing Symptoms: The Influence of Harsh Parenting

Science.gov (United States)

Deardorff, Julianna; Cham, Heining; Gonzales, Nancy A.; White, Rebecca M. B.; Tein, Jenn-Yun; Wong, Jessie J.; Roosa, Mark W.

2013-01-01

Early-maturing girls are at risk for internalizing and externalizing problems. Research concerning pubertal timing and mental health among Mexican Americans or the influence of parenting behaviors on these relations has been scarce. This study addressed these gaps. This was a prospective examination of 362 Mexican-origin girls and their mothers in…

Reconnecting Alaska: Mexican Movements and the Last Frontier

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Sara V. Komarnisky

2012-06-01

Full Text Available This paper discusses the initial findings of on-going research with Mexican migrants and immigrants to Alaska. The paper outlines the historical and on-going connections between Alaska and Mexico and explores how and why those connections have been obscured or ignored. Powerful imaginaries are associated with places: Alaska, and 'the north' more generally, and Latin America, and Mexico specifically. My research shows how interesting things happen when they are brought together through movement. People from Acuitzio del Canje, Michoacán began travelling to Alaska (Anchorage, and elsewhere to work in the 1950s, and movement between Mexico and Alaska has continued across generations since then. Today, many Acuitzences who live in Anchorage maintain a close relationship with friends and family members in Acuitzio, and travel back and forth regularly. However, this movement is obscured by ideological work that makes Alaska seem separate, isolated, wild, and a place where Mexicans are not imagined to be. Mexican movements into Alaska over time disrupt this vision, showing how Alaska is connected to multiple other geographies, and making the US-Mexico border a salient reference point in everyday life in Anchorage. When the South moves into the North, it can make us think about both 'Alaska' and 'Mexico' in different ways. When the US-Mexico border is relocated to Anchorage, if only for a moment, it can elicit a reaction of humour or surprise. Why is that? And what does this have to do with how people actually live in an interconnected place?

The Role of Ethnicity in Mexican American and Non-Hispanic White Students' Experience of Sexual Harassment

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Kearney, Lisa K.; Gilbert, Lucia Albino

2012-01-01

This study explored dimensions of a social phenomenon not often investigated among Mexican American college students, namely sexual harassment. Mexican American (n = 261) and non-Hispanic White female students (n = 111) from three southwestern universities responded to scales assessing experiences of sexually harassing behaviors, harassment…

General overview of the Mexican energy sector

International Nuclear Information System (INIS)

Perez-Jacome, D.

1999-01-01

An overview of Mexico's energy sector was presented, with particular focus on the natural gas and electricity sectors. Mexico ranks fifth in oil production, eighth in proven oil reserves, and fourteenth in natural gas reserves. In 1998, the energy sector generated 3.3 per cent of Mexico's gross domestic product (GDP), and oil accounted for 7.5 per cent of total exports. National production of natural gas has been forecasted to grow at a rate of 5.2 per cent annually over the next 10 years. This will be largely due to the increased demand for natural gas to produce electricity. The Mexican government has also taken initiatives to restructure the Mexican energy sector with particular focus on increasing the competitiveness of the electric power industry. Electricity demand is also expected to grow at a rate of 6 per cent annually over the next six years. The objectives of energy reform are to promote more investment from all sectors in order to strengthen the development of the electric power industry and to provide a reliable, high quality service at competitive prices. 9 figs

Mexican Public Opinion in the aftermath of the 2006 Elections

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Alejandro Moreno

2008-01-01

Full Text Available In this article, I analyze public opinion about the 2006 Mexican presidential election in the context of the post–election conflict. My goal is to determine which individual–level variables influenced opinions about the post–election conflict. The analysis focuses on individual positions about the election fairness, confidence in the electoral Tribunal, claims for a full recount, and the public's stands on street protests and mobilization, among others. I use the Mexican component of the Comparative National Election Project (CNEP, conducted for the first time in Mexico in 2006 as a two–wave, preelection and postelection, panel design. The results highlight the importance of political predispositions in the analysis of public opinion in Mexico.

Long-term surveillance plan for the Mexican Hat disposal site, Mexican Hat, Utah

International Nuclear Information System (INIS)

1996-01-01

This plan describes the long-term surveillance activities for the Uranium Mill Tailings Remedial Action (UMTRA) Project disposal site at Mexican Hat, Utah. The US Department of Energy (DOE) will carry out these activities to ensure that the disposal site continues to function as designed. This long-term surveillance plan (LTSP) was prepared as a requirement for acceptance under the US Nuclear Regulatory Commission (NRC) general license for custody and long-term care of residual radioactive material (RRM). This LTSPC documents the land ownership interests and details how the long-term care of the disposal site will be accomplished

Reading Achievement and In-Grade Retention Rate Differentials for Mexican-American and Black Students in Selected States of the Southwest.

Science.gov (United States)

Casavantes, Edward Joseph

Two sets of data from the U.S. Commission on Civil Rights' Mexican American Education Study were selected for analysis in the areas of (1) comparative reading achievement rates of Mexican Americans and black students; and (2) differential in-grade retention rates of Anglo, Mexican American, and black students. Two separate issues were examined.…

Retrotransposon long interspersed nucleotide element-1 (LINE-1) is activated during salamander limb regeneration

Science.gov (United States)

Zhu, Wei; Kuo, Dwight; Nathanson, Jason; Satoh, Akira; Pao, Gerald M.; Yeo, Gene W.; Bryant, Susan V.; Voss, S. Randal; Gardiner, David M.; Hunter, Tony

2012-01-01

Salamanders possess an extraordinary capacity for tissue and organ regeneration when compared to mammals. In our effort to characterize the unique transcriptional fingerprint emerging during the early phase of salamander limb regeneration, we identified transcriptional activation of some germline-specific genes within the Mexican axolotl (Ambystoma mexicanum) that is indicative of cellular reprogramming of differentiated cells into a germline-like state. In this work, we focus on one of these genes, the long interspersed nucleotide element-1 (LINE-1) retrotransposon, which is usually active in germ cells and silent in most of the somatic tissues in other organisms. LINE-1 was found to be dramatically upregulated during regeneration. In addition, higher genomic LINE-1 content was also detected in the limb regenerate when compared to that before amputation indicating that LINE-1 retrotransposition is indeed active during regeneration. Active LINE-1 retrotransposition has been suggested to have a potentially deleterious impact on genomic integrity. Silencing of activated LINE-1 by small RNAs has been reported to be part of the machinery aiming to maintain genomic integrity. Indeed, we were able to identify putative LINE-1-related piRNAs in the limb blastema. Transposable element-related piRNAs have been identified frequently in the germline in other organisms. Thus, we present here a scenario in which a unique germline-like state is established during axolotl limb regeneration, and the re-activation of LINE-1 may serve as a marker for cellular dedifferentiation in the early-stage of limb regeneration. PMID:22913491

What can we learn from the study of Mexican-origin families in the United States?

Science.gov (United States)

Updegraff, Kimberly A; Umaña-Taylor, Adriana J

2015-06-01

Mexican-origin families are a large and rapidly increasing subgroup of the U.S. population, but they remain underrepresented in family scholarship. This paper introduces a special section of four papers on Mexican-origin families designed to contribute to the advancement of research on how cultural, family, and gender socialization processes unfold across key developmental periods and life transitions in this cultural context. Two longitudinal studies of Mexican-origin families provided the data for these four papers: (a) The Juntos Project, an 8-year longitudinal study of mothers, fathers, and adolescent sibling pairs in 246 Mexican-origin families; and (b) The Supporting MAMI Project, a study following 204 adolescent mothers and their mother figures from the third trimester of pregnancy through their young children's 5th birthdays. In this introductory paper, we highlight four themes, including (a) differential acculturation and reciprocal socialization, (b) interdependence in families, (c) the intersection of culture and gender, and (d) methodological issues. We end with suggestions for future research. © 2015 Family Process Institute.

The Mexican American Woman and Mental Health.

Science.gov (United States)

Gibson, Guadalupe

For a long time Chicanas have been self-denying, self sacrificing. Well, it is time that Mexican American women began thinking of themselves. It follows that if women love and cherish others, they must begin by loving and cherishing themselves. From the mental health perspective it is essential that they do so, not only for their sake, but for…

Genome Sequence of a Novel Archaeal Rudivirus Recovered from a Mexican Hot Spring

DEFF Research Database (Denmark)

Servín-Garcidueñas, L; Peng, X; Garrett, R

2013-01-01

We report the consensus genome sequence of a novel GC-rich rudivirus, designated SMR1 (Sulfolobales Mexican rudivirus 1), assembled from a high-throughput sequenced environmental sample from a hot spring in Los Azufres National Park in western Mexico.......We report the consensus genome sequence of a novel GC-rich rudivirus, designated SMR1 (Sulfolobales Mexican rudivirus 1), assembled from a high-throughput sequenced environmental sample from a hot spring in Los Azufres National Park in western Mexico....

MICROWAVE HEATING AND SEPARATION OF WATER-IN-OIL EMULSION FROM MEXICAN CRUDE OIL

OpenAIRE

VAZQUEZ V., ADRIAN; LOPEZ M., ARTURO; ANDRADE C., LUIS J.; VAZQUEZ A., ARIANA M.

2014-01-01

Microwave heating and gravity sedimentation are alternatives for demulsification and layer separation into oil and water layers, this process was demonstrated in the laboratory and provides an option for reducing and oil recovering from water-in-oil Mexican oil emulsions. The combinatorial process was implemented in a test lab using Mexican crude oil samples. The Laboratory samples were 100% and 50-50%, crude and crude-water respectively, were heated. The results were encouraging show that mi...

Friends' cultural orientation as a mediator between familial ethnic socialization and ethnic identity among Mexican-origin adolescent girls.

Science.gov (United States)

Kim, Peter Seung Yoo; Bámaca-Colbert, Mayra Y; Jian, Ni; Gonzales-Backen, Melinda A

2017-04-01

Research has indicated that ethnic identity protects ethnic minority youth on various indicators of adjustment, but there is a dearth of research pertaining to contextual influences on ethnic identity. Our study investigated how familial ethnic socialization and best friend's orientation toward Mexican culture influenced ethnic identity among Mexican-origin girls. Using a 3-wave longitudinal sample of 175 Mexican-origin adolescent girls (Mage = 13.75), the current study examined best friend's Mexican cultural orientation as a mediator between familial ethnic socialization and ethnic identity with structural equation modeling. Multigroup analyses were conducted to examine potential age and generational status differences within the model. Analyses revealed that familial ethnic socialization promoted ethnic identity exploration and resolution 3.5 years later and that this effect was mediated by best friend's Mexican cultural orientation. No significant differences were found across age or generational status groups. Our study highlights the contribution of peer context to ethnic identity and its role in the process by which familial ethnic socialization influences ethnic identity during adolescence. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Racial Formation in Theory and Practice: The Case of Mexicans in the United States.

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Massey, Douglas S

2009-03-01

Mechanisms of social stratification require the categorical definition of an out-group to that can be excluded and exploited. Historically, in the United States, African Americans have been the subject of a systematic process of racial formation to define socially in this fashion. Beginning in the 1970s, however, and accelerating in the 1980s and 1990s, Mexicans were increasingly subject to processes of racialization that have rendered them more exploitable and excludable than ever before. Over the past decade, Mexican Americans moved steadily away from their middle position in the socioeconomic hierarchy and gravitated toward the bottom. This paper describes the basic mechanisms of stratification in the United States and how Mexicans have steadily been racialized to label them socially as a dehumanized and vulnerable out-group.

PROTEIN & SENSORY ANALYSIS TO CHARACTERIZE MEXICAN CHIHUAHUA CHEESES

Science.gov (United States)

It has been established that native microflora in raw milk cheeses, including Queso Chihuahua, a Mexican cheese variety, contributes to the development of unique flavors through degradation of milk proteins resulting in the release of free amino acids and short peptides that influence the taste and ...

Mexican American Televison: Applied Anthropology and Public Television

Science.gov (United States)

Eiselein, E. B.; Marshall, Wes

1976-01-01

Fiesta Project provides a classic example of action anthropology in broadcasting. The project involved the research and production of a Spanish language public television series designed to attract, retain, and realistically help a Mexican American audience in southern Arizona. The project used anthropological research in initial program…

The prevalence and correlates of severe depression in a cohort of Mexican teachers.

Science.gov (United States)

Soria-Saucedo, Rene; Lopez-Ridaura, Ruy; Lajous, Martin; Wirtz, Veronika J

2018-07-01

Depression is among the 10 major causes of disability in Mexico. Yet, local contextual factors associated to the disorder remain poorly understood. We measured the impact of several factors on severe depression such as demographics, pharmacotherapy, multimorbidity, and unhealthy behaviors in Mexican teachers. A total of 43,845 Mexican female teachers from 12 Mexican states answered the Patient Health Questionnaire (PHQ9). Data were part the Mexican Teacher's Cohort prospective study, the largest ongoing cohort study in Latin America. Unadjusted and adjusted estimates assessed the impact of several contextual factors between severe versus mild-no depression cases. In total 7026 teachers (16%) had a PHQ9 score compatible with severe depression. From them, only 17% received psychotropics, compared to 60% for those with a formal diagnosis. Less than 5% of teachers with PHQ9 scores compatible with severe depression had a formal diagnosis. Adjusted analysis reported higher odds of pharmacotherapy, having ≥ 3 comorbidities, higher levels of couple, family and work stress, fewer hours of vigorous physical activity, higher alcohol consumption, and smoking as risk factors for severe depression. Also, rural residents of northern and center states appeared more severely depressed compared to their urban counterparts. On average, the PHQ9 scores differed by ~ 10 points between severe and mild-no depressed teachers. A cross-sectional design. Also, the study focused on female teachers between ages 25 and 74 years old, reducing the generalizability of the estimates. Under-diagnosis of clinical depression in Mexican teachers is concerning. Unhealthy behavior is associated with severe depression. The information collected in this study represents an opportunity to build prevention mechanisms of depression in high-risk subgroups of female educators and warrants improving access to mental care in Mexico. Copyright © 2018 Elsevier B.V. All rights reserved.

Mexican journalists: an investigation of their emotional health.

Science.gov (United States)

Feinstein, Anthony

2012-08-01

Mexican journalists are frequently the victims of violence, often drug related. The purpose of the study was to assess their mental well-being. Of 104 journalists recruited from 3 news organizations, those who had stopped working on drug-related stories because of intimidation from the criminal drug cartels (n = 26) had significantly greater social dysfunction (p = .024); and more depressive (p = .001) and higher intrusive (p = .027), avoidance (p = .005), and arousal (p = .033) symptoms than journalists living and working under threat in regions of drug violence (n = 61). They also had more arousal (p = .05) and depressive (p = .027) symptoms than journalists (n = 17) never threatened before and living in regions without a drug problem. These findings provide preliminary data on the deleterious effects of drug-related violence on the Mexican media, amplifying the concerns expressed by journalist watchdog organizations monitoring the state of the press in the country. Copyright © 2012 International Society for Traumatic Stress Studies.

Perceived Burdensomeness, Familism, and Suicidal Ideation among Mexican Women: Enhancing Understanding of Risk and Protective Factors

Science.gov (United States)

Garza, Monica J.; Pettit, Jeremy W.

2010-01-01

The interpersonal-psychological theory of suicide and a culturally-relevant construct, familism, was used to examine predictors of suicidal ideation among Mexican and Mexican American women in the United States. A sense of perceived burdensomeness toward others was expected to significantly predict suicidal ideation, especially among women who…

Pubertal Timing and Mexican-Origin Girls’ Internalizing and Externalizing Symptoms: The Influence of Harsh Parenting

Science.gov (United States)

Deardorff, J.; Cham, H.; Gonzales, NA.; White, R.M.B.; Tein, J.-Y.; Wong, J.; Roosa, M.W.

2012-01-01

Early-maturing girls are at risk for internalizing and externalizing problems. Scarce research has examined pubertal timing and mental health among Mexican Americans, or examined the influence of parenting behaviors on these relations. This study addressed these gaps. This was a prospective examination of 362 Mexican-origin girls and their mothers using three waves of data. Measures included girls’ self-report of pubertal development and girls’ and mothers’ report of maternal harsh parenting and daughters’ mental health. Using structural equation modeling, we examined whether pubertal timing in 5th grade predicted girls’ internalizing and externalizing outcomes in 10th grade. We also examined the mediating and moderating effects of harsh parenting on the relations between pubertal timing and internalizing and externalizing behaviors, as well as the influence of mothers’ and daughters’ nativity on these relations. Results differed depending on reporter and maternal nativity. Using daughters’ report, Mexican American mothers’ harsh parenting acted as a moderator. At high levels of harsh parenting, early pubertal timing predicted higher externalizing scores, while at low levels of harsh parenting, early timing predicted lower externalizing scores. For Mexican immigrant mothers, harsh parenting mediated the effects of pubertal timing on girls’ internalizing and externalizing problems. There were no significant pubertal effects for mothers’ report. Findings suggest that maternal harsh parenting plays a key role in the relations between early pubertal timing and behavioral and emotional outcomes among Mexican-origin girls. PMID:23231686

Parent-Child Interactions Among Low-Income Mexican American Parents and Preschoolers: Do Clinic-Referred Families Differ From Nonreferred Families?

Science.gov (United States)

McCabe, Kristen; Yeh, May; Lau, Anna; Argote, Carolina Bertely; Liang, June

2009-01-01

This study compared low-income Mexican American parents of young children referred for behavior problems to their nonreferred counterparts on an observational measure of parent-child interactions. Referred Mexican American parents demonstrated more negative behaviors than their nonreferred counterparts in both nondirective and highly directive situations. However, no differences were found at moderate levels of directiveness. The most and least directive situations in the Dyadic Parent-Child Interaction Coding System best differentiated referred from nonreferred Mexican American families, and families differed more in their negative behaviors than positive behaviors. Many of the parenting behaviors that have been found to differ between referred and nonreferred Caucasian families were also observed to differ between their Mexican American counterparts. PMID:20171330

Genetic Epidemiology of Type 2 Diabetes in Mexican Mestizos

Directory of Open Access Journals (Sweden)

Eiralí Guadalupe García-Chapa

2017-01-01

Full Text Available There are currently about 415 million people with diabetes worldwide, a figure likely to increase to 642 million by 2040. In 2015, Mexico was the second Latin American country and sixth in the world in prevalence of this disorder with nearly 11.5 million of patients. Type 2 diabetes (T2D is the main kind of diabetes and its etiology is complex with environmental and genetic factors involved. Indeed, polymorphisms in several genes have been associated with this disease worldwide. To estimate the genetic epidemiology of T2D in Mexican mestizos a systematic bibliographic search of published articles through PubMed, Scopus, Google Scholar, and Web of Science was conducted. Just case-control studies of candidate genes about T2D in Mexican mestizo inhabitants were included. Nineteen studies that met the inclusion criteria were found. In total, 68 polymorphisms of 41 genes were assessed; 26 of them were associated with T2D risk, which were located in ABCA1, ADRB3, CAPN10, CDC123/CAMK1D, CDKAL1, CDKN2A/2B, CRP, ELMO1, FTO, HHEX, IGF2BP2, IRS1, JAZF1, KCNQ1, LOC387761, LTA, NXPH1, SIRT1, SLC30A8, TCF7L2, and TNF-α genes. Overall, 21 of the 41 analyzed genes were associated with T2D in Mexican mestizos. Such a genetic heterogeneity compares with findings in other ethnic groups.

Consumption and expenditure on food prepared away from home among Mexican adults in 2006

OpenAIRE

Brent A Langellier

2015-01-01

Objective. To describe food expenditure and consumption of foods prepared away from home among Mexican adults. Materials and methods. Data were from 45 241 adult participants in the National Health and Nutrition Survey 2006, a nationally-representative, cross-sectional survey of Mexican households. Descriptive statistics and multivariable linear and logistic regression were used to assess the relationship between location of residence, educational attainment, socioeconomic status and the foll...

Family Stress and Coping for Mexican Origin Adolescents

Science.gov (United States)

Liu, Freda F.; Gonzales, Nancy A.; Fernandez, Aida Cristina; Millsap, Roger E.; Dumka, Larry E.

2011-01-01

Family-related stressors pose special challenges for adolescents of Mexican origin, given traditional cultural norms that compel youths to get involved with family problems despite their limited ability to effect change. The current study examines the prospective effects of coping strategies (i.e., active, distraction, avoidance, support-seeking,…

Determinants of Coping Responses among Mexican American Adolescents.

Science.gov (United States)

Guinn, Bobby; Vincent, Vern

2002-01-01

Examined the relationship of perceived stress, self-esteem, acculturation, and gender to the coping response of Mexican American adolescents. Data from self-report surveys indicated that adolescents had relatively high perceived stress levels, low acculturation, and a moderate self-esteem, with no significant gender differences. Self-esteem was…

Domestic Dramas: Mexican American Music as an Archive of Immigrant Women's Experiences, 1920s-1950s

Science.gov (United States)

Barrera, Magdalena L.

2012-01-01

Mexican women's working and romantic lives were frequent subject matter in early-twentieth-century Mexican American music. Surprisingly, this trend is rendered nearly invisible by the corpus of scholarly work that focuses on the male-centered "heroic corrido," particularly the class and race conflicts represented in that "masculine" genre. This…

Teaching and Learning Critical Reading with Transnational Texts at a Mexican University: An Emergentist Case Study

Science.gov (United States)

Perales Escudero, Moises Damian

2011-01-01

This dissertation project examines the implementation of a critical reading intervention in a Mexican university, and the emergence of target critical reading processes in Mexican college-level EFL readers. It uses a Complexity Theory-inspired, qualitative methodology. Orienting the selection and design of materials is a deep view of culture that…

Mexican Trends: The Next Five Years,

Science.gov (United States)

1985-12-12

either Argentina (60%) or Chile (75%) and far higher than Brazil (26%), whose total debt was around the same size. Second, of the aggregate Mexican...liberalization policies in Brazil, Argentina, and Chile were hammered into place not by politicians and political parties but by technocrats and...accident that violence has exploded in three border cities ( Agua ; Prieta, Piedras Negras, and San Luis) where the opposition had access to the U.S. media

New records of Mexican Tardigrada Nuevos registros de Tardigrada mexicanos

Directory of Open Access Journals (Sweden)

Łukasz Kaczmarek

2011-12-01

Full Text Available In 9 moss samples collected from Mexico, 6 tardigrade species, including 4 new records for the country, were found. The new records raise the number of known Mexican water bear species to forty-one. We provide a full list of the known Mexican tardigrade species and discuss some biogeographical and taxonomic issues.En 9 muestras de musgo recolectadas en México, se encontraron 6 especies de tardígrados, incluyendo 4 nuevos registros para el país. Los nuevos registros incrementaron a 41 el número de especies de tardígrados mexicanos conocidos. Se proporciona una lista completa de tardígrados mexicanos conocidos y se discuten algunas cuestiones biogeográficas y taxonómicas.

A qualitative study of family healthy lifestyle behaviors of Mexican-American and Mexican immigrant fathers and mothers.

Science.gov (United States)

Turner, Barbara J; Navuluri, Neelima; Winkler, Paula; Vale, Shruthi; Finley, Erin

2014-04-01

This study qualitatively examines contrasting parental decision-making styles about family food choices and physical activities as well as willingness to change behaviors among Mexican-American and Mexican immigrant mothers and fathers of school-aged children. Twelve sex-specific focus groups were held in English or Spanish in 2012. Qualitative analysis informed by grounded theory examined parenting styles (ie, authoritative, authoritarian, or permissive), barriers to healthy lifestyle, and parents' stage of change about healthy lifestyles. One third of the 33 participating couples were born in Mexico. The majority of mothers and fathers described being permissive and allowing unhealthy food choices, and a minority of mothers reported more authoritarian approaches to promoting a healthier diet for their children. Mothers were more permissive than fathers about family physical activities and less engaged in these activities. Most mothers and fathers described only contemplating a healthier diet and more physical activity, while wanting their children to have a healthier lifestyle. These data suggest that clinicians need to assess and address differential parental roles when promoting a healthy lifestyle for children. Clinicians should also adopt culturally competent approaches to overcome barriers to parental engagement in diverse aspects of a healthy family lifestyle. Copyright © 2014 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

School Context and the Effect ESL Placement on Mexican-Origin Adolescents’ Achievement*

Science.gov (United States)

Callahan, Rebecca; Wilkinson, Lindsey; Muller, Chandra

2010-01-01

Objectives Immigrant adolescents’ academic achievement is crucial to our future economic stability, and Mexican-origin linguistic minority youth in U.S. schools generally demonstrate lower levels of achievement. English as a Second Language (ESL) programs provide an institutional response to these students’ needs, the effect of which may vary by the proportion of immigrant students in the school. Measures Using propensity score matching and data from the Adolescent Health and Academic Achievement Study (AHAA) and the National Longitudinal Study of Adolescent Health (Add Health), we estimate the effect of ESL placement on Mexican-origin achievement for first-, second-, and third-generation adolescents separately in schools with many and few immigrant students. Results The estimated effect of ESL placement varies by both immigrant concentration in the school and by students’ generational status. Conclusions We find that ESL enrollment may be protective for second-generation Mexican-origin adolescents in high immigrant concentration schools, and may prove detrimental for first-generation adolescents in contexts with few other immigrant students. PMID:20354570

Narcocultura: A Threat to Mexican National Security?

Science.gov (United States)

2012-12-01

Postcolony: The Zapatistas and Narcocultura,” PhD Essay , University of British Colombia: Department of Political Science, 2011, 18. 7 Rafael López...humorous lyrics or tones in some narcocorridos29 Edberg concludes by stating, “cultural images cross...provided inspiration for the lyrics of classical corridos.63 These original corridos became a source of Mexican national identity and a vehicle for

Ecological Risk Assessment of Perchlorate in Avian Species, Rodents, Amphibians and Fish

Science.gov (United States)

2003-04-01

http://www .indiana.edu/- axolotl ). 10.0 JUSTIFICATION OF TEST SYSTEM Perchlorate occurs in ground and surface waters in 44 states in the USA... axolotl ). * Sequentially numbered in order of the date that the change is effective Dept. of Biological Sciences (DBS) Box 43131 Lubbock, TX 79409...KCl, 0.025 giL; CaCh2 H20, 0.65 g/L; MgS04·7H20, 0.1 giL (http://www.indiana.edu/~ axolotl ). *Sequentially numbered in order of the date that the

Brief report: parenting styles and obesity in Mexican American children: a longitudinal study.

Science.gov (United States)

Olvera, Norma; Power, Thomas G

2010-04-01

To assess longitudinally the relations between four parenting styles (authoritative, authoritarian, uninvolved, and indulgent) and child weight status in Mexican American families. Sixty-nine low-income Mexican American mothers and their 4- to 8-year-old children participated in a 4-year longitudinal study. Mothers completed demographic and parenting measures. Children's body weight and height were assessed annually. Body mass index was calculated to determine weight status. At baseline, 65% of children were found to be normal weight, 14% were overweight, and 21% were obese. Analyses examined how parenting styles at baseline predicted child's weight status 3 years later, controlling for initial weight status. Children of indulgent mothers were more likely to become overweight 3 years later than children of authoritative or authoritarian mothers. This study provides longitudinal evidence for the role of indulgent parenting in predicting overweight in Mexican American children. Possible mediating factors that may account for this relationship (e.g., dietary patterns, physical activity patterns, and children's self-regulation) are considered.

[Road traffic injuries in Mexico: evidences to strengthen the Mexican road safety strategy].

Science.gov (United States)

Pérez-Núñez, Ricardo; Híjar, Martha; Celis, Alfredo; Hidalgo-Solórzano, Elisa

2014-05-01

Based on a review of secondary data and the scientific literature and an analysis of the ENSANut-2012 database, the current study provides a comprehensive overview of the current burden of road traffic injuries (RTI) in Mexico and analyzes the country's social response to RTI. The high collision, injury, mortality, and disability rates associated with this public health problem represent a high cost for Mexican society, especially for families. The paper argues that the Mexican response has focused on vehicle occupants while overlooking vulnerable road users and has prioritized strategies with limited effectiveness. Although the country's existing legislation addresses the main risk factors, enforcement has been limited. Finally, the paper makes some recommendations for strengthening the Mexican strategy to prevent RTI, such as safe, equitable, healthy, and sustainable mobility for all types of road users. Despite some strides in RTI prevention, there are still challenges and opportunities to be addressed in the future.

Consumption and expenditure on food prepared away from home among Mexican adults in 2006.

Science.gov (United States)

Langellier, Brent A

2015-01-01

To describe food expenditure and consumption of foods prepared away from home among Mexican adults. Data were from 45 241 adult participants in the National Health and Nutrition Survey 2006, a nationally-representative, cross-sectional survey of Mexican households. Descriptive statistics and multivariable linear and logistic regression were used to assess the relationship between location of residence, educational attainment, socioeconomic status and the following: 1) expenditure on all food and at restaurants, and 2) frequency of consumption of 'comida corrida' or restaurant food and street food. Food expenditure and consumption of food prepared away from home were positively associated with socioeconomic status, educational attainment, and urban vs. rural residence (pConsumption of food prepared outside home may be an important part of the diet among urban Mexican adults and those with high socioeconomic status and educational attainment.

A Model of Maternal and Paternal Ethnic Socialization of Mexican-American Adolescents' Self-Views.

Science.gov (United States)

Knight, George P; Carlo, Gustavo; Streit, Cara; White, Rebecca M B

2017-11-01

Data from a sample of 462 Mexican-American adolescents (M = 10.4 years, SD = .55; 48.1% girls), mothers, and fathers were used to test an ethnic socialization model of ethnic identity and self-efficacy that also considered mainstream parenting styles (e.g., authoritative parenting). Findings supported the ethnic socialization model: parents' endorsement of Mexican-American values were associated with ethnic socialization at fifth grade and seventh grade; maternal ethnic socialization at fifth grade and paternal ethnic socialization at seventh grade were associated with adolescents' ethnic identity exploration at 10th grade and, in turn, self-efficacy at 12th grade. The findings support ethnic socialization conceptions of how self-views of ethnicity develop from childhood across adolescence in Mexican-American children. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

Institutions in the Mexican coffee sector : changes and responses

NARCIS (Netherlands)

Rodriguez Padron, B.

2012-01-01

Keywords: Cooperation, contract arrangements, traders´ performance, market uncertainty, diversification, coffee, Mexico.

The main aim of this thesis is to investigate the institutional environment prevailing in the Mexican coffee sector and its effect on the producers, traders and

The Influence of Cultural Congruency, Communication, and Work Alienation on Employee Satisfaction and Commitment in Mexican Organizations

Science.gov (United States)

Madlock, Paul E.

2012-01-01

This study examined the influence of cultural congruency between societal and organizational cultures on Mexican supervisors' and employees' communication behaviors and employees' work alienation, satisfaction, and commitment. The participants were full time nonmanagement adults working for Mexican owned organizations located in Mexico. This study…

Transmission of Cultural Values among Mexican American Parents and their Adolescent and Emerging Adult Offspring

Science.gov (United States)

Perez-Brena, Norma J.; Updegraff, Kimberly A.; Umaña-Taylor, Adriana J.

2015-01-01

The integration of the U.S. and Mexican culture is an important process associated with Mexican-origin youths’ adjustment and family dynamics. The current study examined the reciprocal associations in parents’ and two offspring’s cultural values (i.e., familism and respect) in 246 Mexican-origin families. Overall, mothers’ values were associated with increases in youths’ values five years later. In contrast, youths’ familism values were associated with increases in fathers’ familism values five years later. In addition, developmental differences emerged where parent-to-offspring effects were more consistent for youth transitioning from early to late adolescence than for youth transitioning from middle adolescence to emerging adulthood. Finally, moderation by immigrant-status revealed a youth-to-parent effect for mother-youth immigrant dyads, but not for dyads where youth were U.S.-raised. Our findings highlight the reciprocal nature of parent-youth value socialization and provide a nuanced understanding of these processes through the consideration of familism and respect values. As Mexican-origin youth represent a large and rapidly growing segment of the U.S. population, research that advances our understanding of how these youth develop values that foster family cohesion and support are crucial. PMID:25470657

INTRODUCING MEXICAN NEEDLETS FOR CMB ANALYSIS: ISSUES FOR PRACTICAL APPLICATIONS AND COMPARISON WITH STANDARD NEEDLETS

International Nuclear Information System (INIS)

Scodeller, S.; Rudjord, Oe.; Hansen, F. K.; Marinucci, D.; Geller, D.; Mayeli, A.

2011-01-01

Over the last few years, needlets have emerged as a useful tool for the analysis of cosmic microwave background (CMB) data. Our aim in this paper is first to introduce into the CMB literature a different form of needlets, known as Mexican needlets, first discussed in the mathematical literature by Geller and Mayeli. We then proceed with an extensive study of the properties of both standard and Mexican needlets; these properties depend on some parameters which can be tuned in order to optimize the performance for a given application. Our second aim in this paper is then to give practical advice on how to adjust these parameters for WMAP and Planck data in order to achieve the best properties for a given problem in CMB data analysis. In particular, we investigate localization properties in real and harmonic space and propose a recipe for quantifying the influence of galactic and point-source masks on the needlet coefficients. We also show that for certain parameter values, the Mexican needlets provide a close approximation to the Spherical Mexican Hat Wavelets (whence their name), with some advantages concerning their numerical implementation and derivation of their statistical properties.

Values and Communication of Chinese, Filipino, European, Mexican, and Vietnamese American Adolescents with Their Families and Friends.

Science.gov (United States)

Cooper, Catherine R.; And Others

1993-01-01

Total of 393 American college students of Chinese, Filipino, European, Mexican, and Vietnamese descent rated their families' familistic values and their relationship with their families. Mexican, Vietnamese, and Filipino descent students endorsed most strongly values regarding mutual support among siblings, whereas all groups reported more formal…

The Relationship between Native American Ancestry, Body Mass Index and Diabetes Risk among Mexican-Americans.

Science.gov (United States)

Hu, Hao; Huff, Chad D; Yamamura, Yuko; Wu, Xifeng; Strom, Sara S

2015-01-01

Higher body mass index (BMI) is a well-established risk factor for type 2 diabetes, and rates of obesity and type 2 diabetes are substantially higher among Mexican-Americans relative to non-Hispanic European Americans. Mexican-Americans are genetically diverse, with a highly variable distribution of Native American, European, and African ancestries. Here, we evaluate the role of Native American ancestry on BMI and diabetes risk in a well-defined Mexican-American population. Participants were randomly selected among individuals residing in the Houston area who are enrolled in the Mexican-American Cohort study. Using a custom Illumina GoldenGate Panel, we genotyped DNA from 4,662 cohort participants for 87 Ancestry-Informative Markers. On average, the participants were of 50.2% Native American ancestry, 42.7% European ancestry and 7.1% African ancestry. Using multivariate linear regression, we found BMI and Native American ancestry were inversely correlated; individuals with ancestry were 2.5 times more likely to be severely obese compared to those with >80% Native American ancestry. Furthermore, we demonstrated an interaction between BMI and Native American ancestry in diabetes risk among women; Native American ancestry was a strong risk factor for diabetes only among overweight and obese women (OR = 1.190 for each 10% increase in Native American ancestry). This study offers new insight into the complex relationship between obesity, genetic ancestry, and their respective effects on diabetes risk. Findings from this study may improve the diabetes risk prediction among Mexican-American individuals thereby facilitating targeted prevention strategies.

Mexican Americans with type 2 diabetes: perspectives on definitions, motivators, and programs of physical activity.

Science.gov (United States)

Mier, Nelda; Medina, Alvaro A; Ory, Marcia G

2007-04-01

Research documents that Mexican Americans bear excess health risk because of physical inactivity and have higher morbidity and mortality rates from chronic diseases than do other ethnic groups. Factors influencing physical activity in this minority population, however, are not well understood. This study examines perceptions of physical activity in a population of Mexican Americans who have type 2 diabetes and live in the Texas-Mexico border region and identifies motivators and barriers to physical activity in this group. This study used a qualitative research design and employed six focus groups comprising 39 Mexican Americans with type 2 diabetes who live in the Texas-Mexico border region. A team of bilingual Mexican American researchers systematically reviewed and analyzed focus group data by means of qualitative data analysis software. The study was conducted during 2005-2006. Most participants considered physical activity to be related not only to exercise but also to occupational and home activities. Walking was the preferred type of activity. Motivators to physical activity included family support and the sense of well-being derived from physical activity. Barriers to physical activity included individual and environmental factors, such as lack of time, physical pain, depression, being overweight, unsafe neighborhoods, and lack of facilities. Participants suggested that the ideal intervention would be low in cost, family-based, close to home, and led by bilingual instructors. Health promotion efforts to prevent or reduce the effects of chronic disease among Mexican Americans with type 2 diabetes in the Texas-Mexico border region should focus on implementing neighborhood-based, family-oriented walking interventions.

Perceived Social Support Trajectories and the All-Cause Mortality Risk of Older Mexican American Women and Men

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Hill, Terrence D.; Uchino, Bert N.; Eckhardt, Jessica L.; Angel, Jacqueline L.

2016-01-01

Although numerous studies of non-Hispanic whites and blacks show that social integration and social support tend to favor longevity, it is unclear whether this general pattern extends to the Mexican American population. Building on previous research, we employed seven waves of data from the Hispanic Established Populations for the Epidemiologic Study of the Elderly to examine the association between perceived social support trajectories and the all-cause mortality risk of older Mexican Americans. Growth mixture estimates revealed three latent classes of support trajectories: high, moderate, and low. Cox regression estimates indicated that older Mexican American men in the low support trajectory tend to exhibit a higher mortality risk than their counterparts in the high support trajectory. Social support trajectories were unrelated to the mortality risk of older Mexican American women. A statistically significant interaction term confirmed that social support was more strongly associated with the mortality risk of men. PMID:26966256

Social Relationships in the Church during Late Life: Assessing Differences between African Americans, Whites, and Mexican Americans.

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Krause, Neal; Bastida, Elena

2011-09-01

The purpose of this study is to see if there are differences in the social relationships that older African Americans, older whites, and older Mexican Americans form with the people where they worship. Data from two nationwide surveys are pooled to see if race differences emerge in eleven different measures of church-based social relationships. These measures assess social relationships with rank-and-file church members as well as social relationships with members of the clergy. The findings reveal that older African Americans tend to have more well-developed social relationships in the church than either older whites or older Mexican Americans. This is true with respect to relationships with fellow church members as well as relationships with the clergy. In contrast, relatively few differences emerged between older Americans of European descent and older Mexican Americans. However, when differences emerged in the data, older whites tend to score higher on the support measures than older Mexican Americans.

Socioeconomic Position, Rural Residence, and Marginality Influences on Obesity Status in the Adult Mexican Population

OpenAIRE

Sparks, P. Johnelle; Sparks, Corey S.

2012-01-01

This paper assesses individual and social environment determinants of obesity in the adult Mexican population based on socioeconomic position, rural residence, and areal deprivation. Using a nationally representative health and nutrition survey, this analysis considers individual and structural determinants of obesity from a socioeconomic position and health disparities conceptual framework using multilevel logistic regression models. We find that more than thirty percent of Mexican adults we...

Cultures of moderation and expression: emotional experience, behavior, and physiology in Chinese Americans and Mexican Americans.

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Soto, José A; Levenson, Robert W; Ebling, Rachel

2005-06-01

Ethnographic accounts suggest that emotions are moderated in Chinese cultures and expressed openly in Mexican cultures. The authors tested this notion by comparing subjective, behavioral, and physiological aspects of emotional responses to 3 (warned, unwarned, instructed to inhibit responding) aversive acoustic startle stimuli in 95 Chinese Americans and 64 Mexican Americans. Subjective reports were consistent with ethnographic accounts; Chinese Americans reported experiencing significantly less emotion than Mexican Americans across all 3 startle conditions. Evidence from a nonemotional task suggested that these differences were not artifacts of cultural differences in the use of rating scales. Few cultural differences were found in emotional behavior or physiology, suggesting that these aspects of emotion are less susceptible to cultural influence.

Assessing the Prayer Lives of Older Whites, Older Blacks and Older Mexican Americans: A Descriptive Analysis

Science.gov (United States)

Krause, Neal

2011-01-01

The purpose of this study was to see whether differences emerge between older whites, older blacks, and older Mexican Americans in 12 measures of prayer. These measures assess four dimensions of prayer: The social context of prayer, interpersonal aspects of prayer, beliefs about how prayer operates, and the content or focus of prayers. Data from two nationwide surveys of older adults suggest that with respect to all four dimensions, the prayer lives of older whites appear be less developed than the prayer lives of older blacks and older Mexican Americans. In contrast, relatively few differences were found in the prayer lives of older African Americans and older Mexican Americans. The theoretical implications of these findings are discussed. PMID:22523464

Profiling neurotransmitter receptor expression in the Ambystoma mexicanum brain.

Science.gov (United States)

Reyes-Ruiz, Jorge Mauricio; Limon, Agenor; Korn, Matthew J; Nakamura, Paul A; Shirkey, Nicole J; Wong, Jamie K; Miledi, Ricardo

2013-03-22

Ability to regenerate limbs and central nervous system (CNS) is unique to few vertebrates, most notably the axolotl (Ambystoma sp.). However, despite the fact the neurotransmitter receptors are involved in axonal regeneration, little is known regarding its expression profile. In this project, RT-PCR and qPCR were performed to gain insight into the neurotransmitter receptors present in Ambystoma. Its functional ability was studied by expressing axolotl receptors in Xenopus laevis oocytes by either injection of mRNA or by direct microtransplantation of brain membranes. Oocytes injected with axolotl mRNA expressed ionotropic receptors activated by GABA, aspartate+glycine and kainate, as well as metabotropic receptors activated by acetylcholine and glutamate. Interestingly, we did not see responses following the application of serotonin. Membranes from the axolotl brain were efficiently microtransplanted into Xenopus oocytes and two types of native GABA receptors that differed in the temporal course of their responses and affinities to GABA were observed. Results of this study are necessary for further characterization of axolotl neurotransmitter receptors and may be useful for guiding experiments aimed at understanding activity-dependant limb and CNS regeneration. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Attitudes toward Suicide among Mexican American and Anglo Youth.

Science.gov (United States)

Domino, George

1981-01-01

There were statistically significant differences between answers of 76 Anglo and 76 Mexican American youth on 35 of 100 opinion questionnaire items. Items centered on religion, psychopathology, aggression-impulsivity, acceptability of suicide, the "cry for help" dimension, and emotional impact. (Author/CM)

The Mexican electricity industry - cogeneration potential

International Nuclear Information System (INIS)

Monroy, I.L.

2000-01-01

A brief history of Mexico's electric power industry is given. Diagrams show (i) the increase in primary energy production from 1990-1998; (ii) energy consumption by sector and (iii) the change in capacity between 1990 and 1998. The projected energy development for 1998-2007 is discussed. The Mexican government has chosen cogeneration to be an important contributor to future energy-efficient power production. Data on installed cogeneration capacity for years 2000 and 2001 are given according to sector

New Mexicans debate nuclear waste disposal

International Nuclear Information System (INIS)

Lepkowski, W.

1979-01-01

A brief survey of the background of the Waste Isolation Plant (WIPP) at Carlsbad, New Mexico and the forces at play around WIPP is presented. DOE has plans to establish by 1988 an underground repository for nuclear wastes in the salt formations near Carlsbad. Views of New Mexicans, both pro and con, are reviewed. It is concluded that DOE will have to practice public persuasion to receive approval for the burial of wastes in New Mexico

CEOs´ monetary incentives and performance of Mexican firms

Directory of Open Access Journals (Sweden)

Karen Watkins-Fassler

2017-02-01

Full Text Available This paper analyzes if changes in CEO remuneration and the execution of CEO stock options impact firm performance, under an emerging market context. Data is obtained from 88 non-financial companies listed in the Mexican Stock Exchange (2001-2012. A dynamic panel specification is employed, and regressions are run through the Generalized Method of Moments. Some evidence is found on the negative relationship between flat monetary incentives and Mexican firm performance, specifically for normal times. In addition, financial incentives based on results (particularly CEO stock options do not imply higher firm performance. Results suggest that companies in particular contexts should move towards the development of CEOs, more than promoting mostly monetary incentives for boosting firm performance. Companies operating in Mexico will gain from hiring intrinsically motivated CEOs, together with testing different extrinsic rewards (neither flat nor stock options in order to attain additive effects on intrinsic motivation.

North American Free Trade Agreement : coordinated operational plan needed to ensure Mexican trucks' compliance with U.S. standards

Science.gov (United States)

2001-12-01

In response to concerns about the safety of Mexican trucks, the General Accounting Office (GAO) was asked to examine (1) the extent to which Mexican-domiciled commercial trucks are likely to travel beyond U.S. border commercial zones once the border ...

The Role of la Familia for Women of Mexican Descent Who Are Leaders in Higher Education

Science.gov (United States)

Elizondo, Sandra Gray

2012-01-01

The purpose of this qualitative case study was to describe the role of "la familia" for women of Mexican descent as it relates to their development as leaders and their leadership in academia. Purposeful sampling was utilized to reach the goal of 18 participants who were female academic leaders of Mexican descent teaching full time in…

A qualitative analysis of posttraumatic stress among Mexican victims of disaster.

Science.gov (United States)

Norris, F H; Weisshaar, D L; Conrad, M L; Diaz, E M; Murphy, A D; Lbañez, G E

2001-10-01

In unstructured interviews, 24 Mexicans described survivors' responses to disasters in Guadalajara, Jalisco (n = 9), Homestead, Florida (n = 6), and Puerto Angel, Oaxaca (n = 9). This analysis assessed the extent to which symptom descriptions corresponded to the 17 criterion symptoms of PTSD. Nineteen participants (79%) mentioned from 1 to 9 criterion symptoms. Event-related distress, hypervigilance, recurrent recollections, and avoiding reminders were described most often. Only 3 criterion symptoms were never described. Twenty participants (83%) provided 109 separate expressions that could not be classified specifically as criterion symptoms. These phrases were sorted by 9 independent Mexican volunteers and cluster analyzed. Clusters composed of ataques de nervios, depression, lasting trauma, and somatic complaints provided the best description of the data.

Psychometric evaluation of the muscle appearance satisfaction scale in a Mexican male sample.

Science.gov (United States)

Escoto Ponce de León, María Del Consuelo; Bosques-Brugada, Lilián Elizabeth; Camacho Ruiz, Esteban Jaime; Alvarez-Rayón, Georgina; Franco Paredes, Karina; Rodríguez Hernández, Gabriela

2017-03-02

The purpose of this study was to determine whether the muscle appearance satisfaction scale (MASS) shows acceptable psychometric properties in Mexican bodybuilders. A total of 258 Mexican male bodybuilders were recruited. Two self-report questionnaires, including the MASS and drive for muscularity scale (DMS), were administered. Six models of the latent structure of the MASS were evaluated, using confirmatory factor analysis with maximum likelihood, considering robust Satorra-Bentler correction to estimate the fit of the models to the data. Similar to the original MASS, the series of CFA confirmed that the Mexican version was well represented with the 17-item five-factor structure, which showed a good model fit [Satorra-Bentler Chi-square (109, n = 258) = 189.18, p McDonald's omega, which was acceptable for the MASS (0.88), and their subscales (0.80 to 0.89), except for muscle checking scale (0.77). Test-retest reliability analysis showed stability of the MASS total as well as of the subscale scores over a 2-week period (intraclass correlation coefficients = 0.75-0.91). Construct validity was demonstrated by a significant positive correlation between MASS and DMS results (r = 0.75; p = 0.0001). These results were similar to those of previous studies, which demonstrate the scale's usefulness. Our results support the suitability of the MASS and its subscales to measure muscle dysmorphia symptoms in Mexican male bodybuilders.

ELECTROCARDIOGRAPHIC ABNORMALITIES AMONG MEXICAN AMERICANS: CORRELATIONS WITH DIABETES, OBESITY, AND THE METABOLIC SYNDROME.

Science.gov (United States)

Queen, Saulette R; Smulevitz, Beverly; Rentfro, Anne R; Vatcheva, Kristina P; Kim, Hyunggun; McPherson, David D; Hanis, Craig L; Fisher-Hoch, Susan P; McCormick, Joseph B; Laing, Susan T

2012-04-01

Resting ischemic electrocardiographic abnormalities have been associated with cardiovascular mortality. Simple markers of abnormal autonomic tone have also been associated with diabetes, obesity, and the metabolic syndrome in some populations. Data on these electrocardiographic abnormalities and correlations with coronary risk factors are lacking among Mexican Americans wherein these conditions are prevalent. This study aimed to evaluate the prevalent resting electrocardiographic abnormalities among community-dwelling Mexican Americans, and correlate these findings with coronary risk factors, particularly diabetes, obesity, and the metabolic syndrome. Study subjects (n=1280) were drawn from the Cameron County Hispanic Cohort comprised of community-dwelling Mexican Americans living in Brownsville, Texas at the United States-Mexico border. Ischemic electrocardiographic abnormalities were defined as presence of ST/T wave abnormalities suggestive of ischemia, abnormal Q waves, and left bundle branch block. Parameters that reflect autonomic tone, such as heart rate-corrected QT interval and resting heart rate, were also measured. Ischemic electrocardiographic abnormalities were more prevalent among older persons and those with hypertension, diabetes, obesity, and the metabolic syndrome. Subjects in the highest quartiles of QTc interval and resting heart rate were also more likely to be diabetic, hypertensive, obese, or have the metabolic syndrome. Among Mexican Americans, persons with diabetes, obesity, and the metabolic syndrome were more likely to have ischemic electrocardiographic abnormalities, longer QTc intervals, and higher resting heart rates. A resting electrocardiogram can play a complementary role in the comprehensive evaluation of cardiovascular risk in this minority population.

A Formal Approach to Discourse Anaphora

Science.gov (United States)

1978-05-01

was given a nut by Wendy, and Druce did 0 too. 0 = ? 41. The aardvark was given two peanuts for its birthday, and the axolotl was 0 too. 0...given two peanuts for its birthday 42. Wendy avoidf the aardvark, and the axolotl was 0 too. 0 = 7 In the case of multiple passives (such as are...the axolotl was 0 too. 0 = given an apple 45. Bert is a super dentist and his father was 0 too. 0 = (be) a super dentist Moreover, it appeals to me

Mexican journals of educational research towards mainstream dissemination of science

Directory of Open Access Journals (Sweden)

Cabrera-Flores, Mayer

2014-08-01

Full Text Available The purpose of this study is to analyze the Electronic Journal of Educational Research (REDIE on its path towards the common manner of scientific dissemination. This research presents the evolution of Mexican policy with regards to the journals, the situation of the Educational Research Mexican journals, and its profundity relating to REDIE. In its evolution, there were three moments that stood out the most: the standardization of quality criteria, the digitalization and open access of the scientific journals, those that came together with REDIE like REDALYC and LATINDEX , and the individual initiatives of those journals that motivated the development of the scientific dissemination in Mexico. The investigation concludes with the realization of the necessity of achieving agreement on the efforts of various principal actors: governmental bodies, institutions, and academic communities.

Abdominal obesity is strongly associated to blood pressure in young Mexicans.

Science.gov (United States)

Urquidez Romero, Rene; Murguía Romero, Miguel; Esparza Romero, Julián; Díaz Torres, Beatriz Araceli; Rodríguez Tadeo, Alejandra; Medrano Donlucas, Gabriel; Ramos Jiménez, Arnulfo; Wall Medrano, Abraham; Gallardo Ortíz, Itzell A; Tapia Pancardo, Diana C Tapia-Pancardo C; Méndez Cruz, A René; Jiménez Flores, J Rafael; Villalobos Molina, Rafael

2017-03-30

The objective of this study was to determine associations between abdominal obesity (AOb) and the other components of metabolic syndrome (MetS) in young Mexicans in a cross-sectional survey completed during a 4 year period. This cross-sectional study reports on components and prevalence of MetS by using Alberti et al. (16) criteria, as well as association between AOb and elevated blood pressure (BP) of 2,993 Mexican university students, ages 17 to 25 years (66% women) from central and northern Mexico, over a 4-year survey (2010-2013). The most prevalent MetS components in the total sample were low HDL-C concentration (43.6%) and AOb (41.1%). MetS prevalence was 11.8%, more men than women were classified with MetS (14.3% vs. 10.5%, p < 0.01). BP was the MetS component with the lowest prevalence (8.6%). A strong association between AOb and altered BP with in both men and women was found (OR 4.3, IC95% 2.5-7.4). Even BP was the component with the lowest prevalence, AOb was more strongly associated with it. This fact, could explain the prevalence of hypertension among young Mexican adults.

DNA barcode identification of commercial fish sold in Mexican markets.

Science.gov (United States)

Sarmiento-Camacho, Stephanie; Valdez-Moreno, Martha

2018-04-24

The substitution of high-value fish species for those of lower value is common practice. Although numerous studies have addressed this issue, few have been conducted in Mexico. In this study, we sought to identify fresh fillets of fish, sharks, and rays using DNA barcodes. We analyzed material from "La Viga" in Mexico City, and other markets located on the Gulf and Caribbean coasts of Mexico. From 134 samples, we obtained sequences from 129, identified to 9 orders, 28 families, 38 genera, and 44 species. The most common species were Seriola dumerili, Pangasianodon hypophthalmus, Carcharhinus falciformis, Carcharhinus brevipinna, and Hypanus americanus. Pangasianodon hypophthalmus was most commonly used as a substitute for higher-value species. The substitution rate was 18% of the total. A review of the conservation status of the specimens identified against the IUNC list enabled us to establish that some species marketed in Mexico are threatened: Makaira nigricans, Lachnolaimus maximus, Hyporthodus flavolimbatus, and Isurus oxyrinchus are classified as vulnerable; Lopholatilus chamaeleonticeps and Sphyrna lewini are endangered; and the status of Hyporthodus nigritus is critical. These results will demonstrate to the Mexican authorities that DNA barcoding is a reliable tool for species identification, even when morphological identification is difficult or impossible.

Mexican registry of pulmonary hypertension: REMEHIP.

Science.gov (United States)

Sandoval Zarate, Julio; Jerjes-Sanchez, Carlos; Ramirez-Rivera, Alicia; Zamudio, Tomas Pulido; Gutierrez-Fajardo, Pedro; Elizalde Gonzalez, Jose; Leon, Mario Seoane Garcia De; Gamez, Miguel Beltran; Abril, Francisco Moreno Hoyos; Michel, Rodolfo Parra; Aguilar, Humberto Garcia

REMEHIP is a prospective, multicentre registry on pulmonary hypertension. The main objective will be to identify the clinical profile, medical care, therapeutic trends and outcomes in adult and pediatric Mexican patients with well-characterized pulmonary hypertension. REMEHIP a multicenter registry began in 2015 with a planned recruitment time of 12 months and a 4-year follow-up. The study population will comprise a longitudinal cohort study, collecting data on patients with prevalent and incident pulmonary hypertension. Will be included patients of age >2 years and diagnosis of pulmonary hypertension by right heart catheterization within Group 1 and Group 4 of the World Health Organization classification. The structure, data collection and data analysis will be based on quality current recommendations for registries. The protocol has been approved by institutional ethics committees in all participant centers. All patients will sign an informed consent form. Currently in Mexico, there is a need of observational registries that include patients with treatment in the everyday clinical practice so the data could be validated and additional information could be obtained versus the one from the clinical trials. In this way, REMEHIP emerges as a link among randomized clinical trials developed by experts and previous Mexican experience. Copyright © 2016 Instituto Nacional de Cardiología Ignacio Chávez. Publicado por Masson Doyma México S.A. All rights reserved.

Time and space: undergraduate Mexican physics in motion

Science.gov (United States)

Candela, Antonia

2010-09-01

This is an ethnographic study of the trajectories and itineraries of undergraduate physics students at a Mexican university. In this work learning is understood as being able to move oneself and, other things (cultural tools), through the space-time networks of a discipline (Nespor in Knowledge in motion: space, time and curriculum in undergraduate physics and management. Routledge Farmer, London, 1994). The potential of this socio-cultural perspective allows an analysis of how students are connected through extended spaces and times with an international core discipline as well as with cultural features related to local networks of power and construction. Through an example, I show that, from an actor-network-theory (Latour in Science in action. Harvard University Press, Cambridge, 1987), that in order to understand the complexities of undergraduate physics processes of learning you have to break classroom walls and take into account students' movements through complex spatial and temporal traces of the discipline of physics. Mexican professors do not give classes following one textbook but in a moment-to-moment open dynamism tending to include undergraduate students as actors in classroom events extending the teaching space-time of the classroom to the disciplinary research work of physics. I also find that Mexican undergraduate students show initiative and display some autonomy and power in the construction of their itineraries as they are encouraged to examine a variety of sources including contemporary research articles, unsolved physics problems, and even to participate in several physicists' spaces, as for example being speakers at the national congresses of physics. Their itineraries also open up new spaces of cultural and social practices, creating more extensive networks beyond those associated with a discipline. Some economic, historical and cultural contextual features of this school of sciences are analyzed in order to help understanding the particular

Pandemics and networks : The case of the Mexican flu

NARCIS (Netherlands)

Omic, J.; Van Mieghem, P.

2010-01-01

The recent widespread of the new Mexican flu and SARS show the high dependency on contemporary traveling patterns. The air transport network is recognized as an important channel of epidemic propagation for different diseases. In order to predict epidemic spreading and the influence of protection

The Attitudes of Mexican Parents Toward School Discipline

Science.gov (United States)

Ogletree, Earl J.; Rodriquez, Margarita

1978-01-01

Surveys the attitudes of Mexican parents toward school discipline of primary-level children in terms of the following questions: 1) will parents accept the use of corporal punishment in schools?, 2) what form of disciplinary measure will they accept or recommend?, 3) if parents accept corporal punishment, who will be the school disciplinarian, and…