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Sample records for juvenile mexican axolotls

  1. Forever young: Endocrinology of paedomorphosis in the Mexican axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    De Groef, Bert; Grommen, Sylvia V H; Darras, Veerle M

    2018-05-16

    The Mexican axolotl (Ambystoma mexicanum) is a salamander species that does not undergo metamorphosis, resulting in the retention of juvenile characteristics in the mature breeding stage (paedomorphosis). Here we review the endocrinological studies investigating the proximate cause of axolotl paedomorphosis with a focus on the hypothalamo-pituitary-thyroid (HPT) axis. It is well established that axolotl paedomorphosis is a consequence of low activity of the HPT axis. The pituitary hormone thyrotropin (TSH) is capable of inducing metamorphosis in the axolotl, which indicates that all processes and interactions in the HPT axis below the pituitary level are functional, but that TSH release is impaired. In metamorphosing species, TSH secretion is largely controlled by the hypothalamic neuropeptide corticotropin-releasing hormone (CRH), which seems to have lost its thyrotropic activity in the axolotl. However, preliminary experiments have not yet confirmed a role for faulty CRH signalling in axolotl paedomorphosis. Other hypothalamic factors and potential pituitary inhibitors need to be investigated to identify their roles in amphibian metamorphosis and axolotl paedomorphosis. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. The Mexican Axolotl in Schools

    Science.gov (United States)

    Thomas, R. M.

    1976-01-01

    Suggests and describes laboratory activities in which the Mexican axolotl (Ambystoma mexicanum Shaw) is used, including experiments in embryology and early development, growth and regeneration, neoteny and metamorphosis, genetics and coloration, anatomy and physiology, and behavior. Discusses care and maintenance of animals. (CS)

  3. Housing and maintenance of Ambystoma mexicanum, the Mexican axolotl.

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    Farkas, Johanna E; Monaghan, James R

    2015-01-01

    The aim of this paper is to assemble a significant amount of information on Ambystoma mexicanum, the axolotl salamander, to assist in the basic knowledge needed to raise, breed, and study most aspects of axolotl biology. It is important to understand the basic biology of the axolotl in order to make informed decisions on their proper care and use in experiments. Therefore, we will provide necessary information to the non-herpetologist that will assist in their study of this unique and fascinating animal. We also aim to provide a resource on the general anatomy, behavior, and experimental tips specific to the Mexican axolotl that will be of use to most axolotl laboratories. Axolotls have been actively researched since the 1860s, giving testament to their relatively straightforward maintenance and their versatility as an animal model for development and regeneration. Interest in using the axolotl in laboratory research has grown tremendously over the past decade, so dedicated resources to support the study of this species are needed and encouraged.

  4. Role of Myofibril-Inducing RNA in cardiac TnT expression in developing Mexican axolotl

    Science.gov (United States)

    Sferrazza, Gian-Franco; Zhang, Chi; Jia, Pingping; Lemanski, Sharon L.; Athauda, Gagani; Stassi, Alyssa; Halager, Kristine; Maier, Jennifer A.; Rueda-de-Leon, Elena; Gupta, Amit; Dube, Syamalima; Huang, Xupei; Prentice, Howard M.; Dube, Dipak K.; Lemanski, Larry F.

    2007-01-01

    The Mexican axolotl, Ambystoma mexicanum, has been a useful animal model to study heart development and cardiac myofibrillogenesis. A naturally-occurring recessive mutant, gene “c”, for cardiac non-function in the Mexican axolotl causes a failure of myofibrillogenesis due to a lack of tropomyosin expression in homozygous mutant (c/c) embryonic hearts.. Myofibril-Inducing RNA (MIR) rescues mutant hearts in vitro by promoting tropomyosin expression and myofibril formation thereafter. We have studied the effect of MIR on the expression of various isoforms of cardiac Troponin-T (cTnT), a component of the thin filament that binds with tropomyosin. Four alternatively spliced cTnT isoforms have been characterized from developing axolotl heart. The expression of various cTnT isoforms in normal, mutant, and mutant hearts corrected with MIR, is evaluated by real-time RT-PCR using isoform specific primer pairs; MIR affects the total transcription as well as the splicing of the cTnT in axolotl heart PMID:17408593

  5. Regulation of antibody synthesis in the X-irradiated Mexican axolotl

    International Nuclear Information System (INIS)

    Charlemagne, J.

    1981-01-01

    The effects of X-irradiation were studied on the Mexican axolotl antibody synthesis. To reduce the anti-horse red blood cell (HRBC) antibody titers, 150 rd and smaller doses are ineffective, 200-450 rd are increasingly effective, and 700 rd are maximally effective (and lethal). A significant enhancement of the anti-HRBC titers was observed in low doses (50-150 rd X-irradiated animals). This enhancement was also observed when a low X-ray dose was applied only on the thymic areas. In whole body, but thymus area-shielded, 100 rd X-irradiated animals, the anti-HRBC titers were similar to those of the nonirradiated, HRBC-immunized control group. To explain these phenomena, it is suggested that a radiosensitive, adult thymectomy-sensitive and hydrocortisone-sensitive suppressor T cell subpopulation regulates the antibody synthesis in the axolotl. (orig.) [de

  6. Regulation of antibody synthesis in the X-irradiated Mexican axolotl

    Energy Technology Data Exchange (ETDEWEB)

    Charlemagne, J.

    1981-09-01

    The effects of X-irradiation were studied on the Mexican axolotl antibody synthesis. To reduce the anti-horse red blood cell (HRBC) antibody titers, 150 rd and smaller doses are ineffective, 200-450 rd are increasingly effective, and 700 rd are maximally effective (and lethal). A significant enhancement of the anti-HRBC titers was observed in low doses (50-150 rd X-irradiated animals). This enhancement was also observed when a low X-ray dose was applied only on the thymic areas. In whole body, but thymus area-shielded, 100 rd X-irradiated animals, the anti-HRBC titers were similar to those of the nonirradiated, HRBC-immunized control group. To explain these phenomena, it is suggested that a radiosensitive, adult thymectomy-sensitive and hydrocortisone-sensitive suppressor T cell subpopulation regulates the antibody synthesis in the axolotl.

  7. Effect of thyroid hormone concentration on the transcriptional response underlying induced metamorphosis in the Mexican axolotl (Ambystoma).

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    Page, Robert B; Voss, Stephen R; Samuels, Amy K; Smith, Jeramiah J; Putta, Srikrishna; Beachy, Christopher K

    2008-02-11

    Thyroid hormones (TH) induce gene expression programs that orchestrate amphibian metamorphosis. In contrast to anurans, many salamanders do not undergo metamorphosis in nature. However, they can be induced to undergo metamorphosis via exposure to thyroxine (T4). We induced metamorphosis in juvenile Mexican axolotls (Ambystoma mexicanum) using 5 and 50 nM T4, collected epidermal tissue from the head at four time points (Days 0, 2, 12, 28), and used microarray analysis to quantify mRNA abundances. Individuals reared in the higher T4 concentration initiated morphological and transcriptional changes earlier and completed metamorphosis by Day 28. In contrast, initiation of metamorphosis was delayed in the lower T4 concentration and none of the individuals completed metamorphosis by Day 28. We identified 402 genes that were statistically differentially expressed by > or = two-fold between T4 treatments at one or more non-Day 0 sampling times. To complement this analysis, we used linear and quadratic regression to identify 542 and 709 genes that were differentially expressed by > or = two-fold in the 5 and 50 nM T4 treatments, respectively. We found that T4 concentration affected the timing of gene expression and the shape of temporal gene expression profiles. However, essentially all of the identified genes were similarly affected by 5 and 50 nM T4. We discuss genes and biological processes that appear to be common to salamander and anuran metamorphosis, and also highlight clear transcriptional differences. Our results show that gene expression in axolotls is diverse and precise, and that axolotls provide new insights about amphibian metamorphosis.

  8. Using Ambystoma mexicanum (Mexican axolotl) embryos, chemical genetics, and microarray analysis to identify signaling pathways associated with tissue regeneration.

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    Ponomareva, Larissa V; Athippozhy, Antony; Thorson, Jon S; Voss, S Randal

    2015-12-01

    Amphibian vertebrates are important models in regenerative biology because they present exceptional regenerative capabilities throughout life. However, it takes considerable effort to rear amphibians to juvenile and adult stages for regeneration studies, and the relatively large sizes that frogs and salamanders achieve during development make them difficult to use in chemical screens. Here, we introduce a new tail regeneration model using late stage Mexican axolotl embryos. We show that axolotl embryos completely regenerate amputated tails in 7days before they exhaust their yolk supply and begin to feed. Further, we show that axolotl embryos can be efficiently reared in microtiter plates to achieve moderate throughput screening of soluble chemicals to investigate toxicity and identify molecules that alter regenerative outcome. As proof of principle, we identified integration 1 / wingless (Wnt), transforming growth factor beta (Tgf-β), and fibroblast growth factor (Fgf) pathway antagonists that completely block tail regeneration and additional chemicals that significantly affected tail outgrowth. Furthermore, we used microarray analysis to show that inhibition of Wnt signaling broadly affects transcription of genes associated with Wnt, Fgf, Tgf-β, epidermal growth factor (Egf), Notch, nerve growth factor (Ngf), homeotic gene (Hox), rat sarcoma/mitogen-activated protein kinase (Ras/Mapk), myelocytomatosis viral oncogene (Myc), tumor protein 53 (p53), and retinoic acid (RA) pathways. Punctuated changes in the expression of genes known to regulate vertebrate development were observed; this suggests the tail regeneration transcriptional program is hierarchically structured and temporally ordered. Our study establishes the axolotl as a chemical screening model to investigate signaling pathways associated with tissue regeneration. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Effect of thyroid hormone concentration on the transcriptional response underlying induced metamorphosis in the Mexican axolotl (Ambystoma

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    Samuels Amy K

    2008-02-01

    Full Text Available Abstract Background Thyroid hormones (TH induce gene expression programs that orchestrate amphibian metamorphosis. In contrast to anurans, many salamanders do not undergo metamorphosis in nature. However, they can be induced to undergo metamorphosis via exposure to thyroxine (T4. We induced metamorphosis in juvenile Mexican axolotls (Ambystoma mexicanum using 5 and 50 nM T4, collected epidermal tissue from the head at four time points (Days 0, 2, 12, 28, and used microarray analysis to quantify mRNA abundances. Results Individuals reared in the higher T4 concentration initiated morphological and transcriptional changes earlier and completed metamorphosis by Day 28. In contrast, initiation of metamorphosis was delayed in the lower T4 concentration and none of the individuals completed metamorphosis by Day 28. We identified 402 genes that were statistically differentially expressed by ≥ two-fold between T4 treatments at one or more non-Day 0 sampling times. To complement this analysis, we used linear and quadratic regression to identify 542 and 709 genes that were differentially expressed by ≥ two-fold in the 5 and 50 nM T4 treatments, respectively. Conclusion We found that T4 concentration affected the timing of gene expression and the shape of temporal gene expression profiles. However, essentially all of the identified genes were similarly affected by 5 and 50 nM T4. We discuss genes and biological processes that appear to be common to salamander and anuran metamorphosis, and also highlight clear transcriptional differences. Our results show that gene expression in axolotls is diverse and precise, and that axolotls provide new insights about amphibian metamorphosis.

  10. 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.

  11. Identification of Conserved and Novel MicroRNAs during Tail Regeneration in the Mexican Axolotl

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    Micah D. Gearhart

    2015-09-01

    Full Text Available The Mexican axolotl salamander (Ambystoma mexicanum is one member of a select group of vertebrate animals that have retained the amazing ability to regenerate multiple body parts. In addition to being an important model system for regeneration, the axolotl has also contributed extensively to studies of basic development. While many genes known to play key roles during development have now been implicated in various forms of regeneration, much of the regulatory apparatus controlling the underlying molecular circuitry remains unknown. In recent years, microRNAs have been identified as key regulators of gene expression during development, in many diseases and also, increasingly, in regeneration. Here, we have used deep sequencing combined with qRT-PCR to undertake a comprehensive identification of microRNAs involved in regulating regeneration in the axolotl. Specifically, among the microRNAs that we have found to be expressed in axolotl tissues, we have identified 4564 microRNA families known to be widely conserved among vertebrates, as well as 59,811 reads of putative novel microRNAs. These findings support the hypothesis that microRNAs play key roles in managing the precise spatial and temporal patterns of gene expression that ensures the correct regeneration of missing tissues.

  12. Highly restricted diversity of TCR delta chains of the amphibian Mexican axolotl (Ambystoma mexicanum) in peripheral tissues.

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    André, Sébastien; Kerfourn, Fabienne; Affaticati, Pierre; Guerci, Aline; Ravassard, Philippe; Fellah, Julien S

    2007-06-01

    Gammadelta T cells localize at mammalian epithelial surfaces to exert both protective and regulatory roles in response to infections. We have previously characterized the Mexican axolotl (Ambystoma mexicanum) T cell receptor delta (TRD) chain. In this study, TRD repertoires in spleen, liver, intestine and skin from larvae, pre-adult and adult axolotls were examined and compared to the thymic TRD repertoire. A TRDV transcript without N/D diversity, TRDV1S1-TRDJ1, dominates the TRD repertoires until sexual maturation. In adult tissues, this canonical transcript is replaced by another dominant TRDV1S1-TRDJ1 transcript. In the thymus, these two transcripts are detected early in development. Our results suggest that gammadelta T cells that express the canonical TRDV1S1-TRDJ1 transcript emerge from the thymus and colonize the peripheral tissues, where they are selectively expanded by recurrent ligands. This particular situation is probably related to the neotenic state and the slow development of the axolotl. In thymectomized axolotls, TRD repertoires appear different from those of normal axolotls, suggesting that extrathymic gammadelta T cell differentiation could occur. Gene expression analysis showed the importance of the gut in T cell development.

  13. Molecular and immunohistochemical analyses of cardiac troponin T during cardiac development in the Mexican axolotl, Ambystoma mexicanum.

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    Zhang, C; Pietras, K M; Sferrazza, G F; Jia, P; Athauda, G; Rueda-de-Leon, E; Rveda-de-Leon, E; Maier, J A; Dube, D K; Lemanski, S L; Lemanski, L F

    2007-01-01

    The Mexican axolotl, Ambystoma mexicanum, is an excellent animal model for studying heart development because it carries a naturally occurring recessive genetic mutation, designated gene c, for cardiac nonfunction. The double recessive mutants (c/c) fail to form organized myofibrils in the cardiac myoblasts resulting in hearts that fail to beat. Tropomyosin expression patterns have been studied in detail and show dramatically decreased expression in the hearts of homozygous mutant embryos. Because of the direct interaction between tropomyosin and troponin T (TnT), and the crucial functions of TnT in the regulation of striated muscle contraction, we have expanded our studies on this animal model to characterize the expression of the TnT gene in cardiac muscle throughout normal axolotl development as well as in mutant axolotls. In addition, we have succeeded in cloning the full-length cardiac troponin T (cTnT) cDNA from axolotl hearts. Confocal microscopy has shown a substantial, but reduced, expression of TnT protein in the mutant hearts when compared to normal during embryonic development. 2006 Wiley-Liss, Inc.

  14. 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.

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

    OpenAIRE

    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

    2012-01-01

    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 ce...

  16. 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

  17. An introduction to the Mexican axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Gresens, Jill

    2004-10-01

    A number of unusual traits, including a remarkable capacity for wound healing and limb regeneration, make the axolotl an interesting animal model. The author provides an overview of axolotl care and use in biomedical research.

  18. Resegmentation in the Mexican axolotl, Ambystoma mexicanum.

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    Piekarski, Nadine; Olsson, Lennart

    2014-02-01

    The segmental series of somites in the vertebrate embryo gives rise to the axial skeleton. In amniote models, single vertebrae are derived from the sclerotome of two adjacent somites. This process, known as resegmentation, is well-studied using the quail-chick chimeric system, but the presumed generality of resegmentation across vertebrates remains poorly evaluated. Resegmentation has been questioned in anamniotes, given that the sclerotome is much smaller and lacks obvious differentiation between cranial and caudal portions. Here, we provide the first experimental evidence that resegmentation does occur in a species of amphibian. Fate mapping of individual somites in the Mexican axolotl (Ambystoma mexicanum) revealed that individual vertebrae receive cells from two adjacent somites as in the chicken. These findings suggest that large size and segmentation of the sclerotome into distinct cranial and caudal portions are not requirements for resegmentation. Our results, in addition to those for zebrafish, indicate that resegmentation is a general process in building the vertebral column in vertebrates, although it may be achieved in different ways in different groups. Copyright © 2013 Wiley Periodicals, Inc.

  19. Evolutionary genetics of metamorphic failure using wild-caught vs. laboratory axolotls (Ambystoma mexicanum).

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    Voss, S R; Shaffer, H B

    2000-09-01

    In many organisms metamorphosis allows for an ecologically important habitat-shift from water to land. However, in some salamanders an adaptive life cycle mode has evolved that is characterized by metamorphic failure (paedomorphosis); these species remain in the aquatic habitat throughout the life cycle. Perhaps the most famous example of metamorphic failure is the Mexican axolotl (Ambystoma mexicanum), which has become a focal species for developmental biology since it was introduced into laboratory culture in the 1800s. Our previous genetic linkage mapping analysis, using an interspecific crossing design, demonstrated that a major gene effect underlies the expression of metamorphic failure in laboratory stocks of the Mexican axolotl. Here, we repeated this experiment using A. mexicanum that were sampled directly from their natural habitat at Lake Xochimilco, Mexico. We found no significant association between the major gene and metamorphic failure when wild-caught axolotls were used in the experimental design, although there is evidence of a smaller genetic effect. Thus, there appears to be genetic variation among Mexican axolotls (and possibly A. tigrinum tigrinum) at loci that contribute to metamorphic failure. This result suggests a role for more than one mutation and possibly artificial selection in the evolution of the major gene effect in the laboratory Mexican axolotl.

  20. Evaluation of the anesthetic effects of MS222 in the adult Mexican axolotl (Ambystoma mexicanum

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    Zullian C

    2016-01-01

    Full Text Available Chiara Zullian,1 Aurore Dodelet-Devillers,1 Stéphane Roy,2 Pascal Vachon1 1Département de Biomédecine Vétérinaire, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, 2Département de Stomatologie, Faculté de Médecine Dentaire, Montréal, Québec, Canada Abstract: The Mexican axolotl (Ambystoma mexicanum is a unique research model in several fields of medicine, where surgical and invasive procedures may be required. As yet, little is known about the efficacy of MS222 (tricaine methanesulfonate, which is the most commonly used anesthetic agent in amphibians. The main objectives of this study were to evaluate the anesthetic effects and physiological changes in adult axolotls following a 20-minute immersion bath, containing progressive MS222 concentrations starting at 0.1%. Depth of anesthesia and physiological changes were evaluated every 15 minutes post-MS222 exposure with the following parameters: righting behavior, withdrawal reflex, acetic acid test response, heart rate, and blood oxygen saturation, as well as cloacal and body surface temperatures. A 20-minute exposure in a 0.1% MS222 immersion bath (n=6 animals had no anesthetic effects on adult axolotls after 20 minutes of exposure. With a 0.2% MS222 solution, all axolotls (n=9 were deeply anesthetized at 15 minutes, and 80% were still unresponsive at 30 minutes postexposure. Blood oxygen saturation and heart rate were slightly, but significantly, increased when compared with the baseline value and remained stable up to recovery. There was no significant increase in surface and cloaca temperatures, compared with baseline. With the 0.4% MS222 solution, the duration of anesthesia lasted for 90 minutes to at least 120 minutes (n=3 animals and this concentration was deemed too high. In conclusion, a 20-minute immersion bath with 0.2% MS222 may be used for short procedures (15–30 minutes requiring anesthesia of adult axolotls. Keywords: Ambystoma mexicanum

  1. 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 neurophysiologi......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...

  2. 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.

  3. Optimized axolotl (Ambystoma mexicanum) husbandry, breeding, metamorphosis, transgenesis and tamoxifen-mediated recombination.

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    Khattak, Shahryar; Murawala, Prayag; Andreas, Heino; Kappert, Verena; Schuez, Maritta; Sandoval-Guzmán, Tatiana; Crawford, Karen; Tanaka, Elly M

    2014-03-01

    The axolotl (Mexican salamander, Ambystoma mexicanum) has become a very useful model organism for studying limb and spinal cord regeneration because of its high regenerative capacity. Here we present a protocol for successfully mating and breeding axolotls in the laboratory throughout the year, for metamorphosing axolotls by a single i.p. injection and for axolotl transgenesis using I-SceI meganuclease and the mini Tol2 transposon system. Tol2-mediated transgenesis provides different features and advantages compared with I-SceI-mediated transgenesis, and it can result in more than 30% of animals expressing the transgene throughout their bodies so that they can be directly used for experimentation. By using Tol2-mediated transgenesis, experiments can be performed within weeks (e.g., 5-6 weeks for obtaining 2-3-cm-long larvae) without the need to establish germline transgenic lines (which take 12-18 months). In addition, we describe here tamoxifen-induced Cre-mediated recombination in transgenic axolotls.

  4. Role of cranial neural crest cells in visceral arch muscle positioning and morphogenesis in the Mexican axolotl, Ambystoma mexicanum.

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    Ericsson, Rolf; Cerny, Robert; Falck, Pierre; Olsson, Lennart

    2004-10-01

    The role of cranial neural crest cells in the formation of visceral arch musculature was investigated in the Mexican axolotl, Ambystoma mexicanum. DiI (1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine, perchlorate) labeling and green fluorescent protein (GFP) mRNA injections combined with unilateral transplantations of neural folds showed that neural crest cells contribute to the connective tissues but not the myofibers of developing visceral arch muscles in the mandibular, hyoid, and branchial arches. Extirpations of individual cranial neural crest streams demonstrated that neural crest cells are necessary for correct morphogenesis of visceral arch muscles. These do, however, initially develop in their proper positions also in the absence of cranial neural crest. Visceral arch muscles forming in the absence of neural crest cells start to differentiate at their origins but fail to extend toward their insertions and may have a frayed appearance. Our data indicate that visceral arch muscle positioning is controlled by factors that do not have a neural crest origin. We suggest that the cranial neural crest-derived connective tissues provide directional guidance important for the proper extension of the cranial muscles and the subsequent attachment to the insertion on the correct cartilage. In a comparative context, our data from the Mexican axolotl support the view that the cranial neural crest plays a fundamental role in the development of not only the skeleton of the vertebrate head but also in the morphogenesis of the cranial muscles and that this might be a primitive feature of cranial development in vertebrates. 2004 Wiley-Liss, Inc.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  7. Musashi and Plasticity of Xenopus and Axolotl Spinal Cord Ependymal Cells

    Science.gov (United States)

    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

  8. 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

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

    Science.gov (United States)

    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

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

    DEFF Research Database (Denmark)

    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...

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

    DEFF Research Database (Denmark)

    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...

  12. Experimentally induced metamorphosis in axolotls reduces regenerative rate and fidelity

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

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

    DEFF Research Database (Denmark)

    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...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  5. Juvenile Justice in Mexico

    Directory of Open Access Journals (Sweden)

    Martha Frías Armenta

    2014-08-01

    Full Text Available The first tribunal in Mexico was established in the central state of San Luis Potosi in 1926. The Law Regarding Social Prevention and Juvenile Delinquency for the Federal District and Mexican territories was promulgated in 1928. In 2005, Article 18 of the Mexican Constitution was modified to establish a comprehensive system (“Sistema Integral de justicia” in Spanish of justice for juveniles between 12 and 18 years old who had committed a crime punishable under criminal law. Its objective was to guarantee juveniles all the due process rights established for adults, in addition to the special ones recognized for minors. The constitutional reform also provides a framework that includes special tribunals as well as alternative justice options for juveniles. With these reforms, institutionalization of minors was to be considered an extreme measure applicable only to felonies and to juveniles older than 14. In 2006, all states within the Mexican federation enacted the “Law of justice for adolescents”. This system, at both the federal and state levels, formalizes a new global paradigm with regard to the triangular relationship between children, the State and the Law. It recognizes that children are also bearers of the inherent human rights recognized for all individuals, instead of simply objects in need of protection. However, despite formally aligning Mexican juvenile justice law with the Convention on the Rights of the Child (CRC, issues of actual substantive rights remained and new ones have appeared. For example, juveniles younger than 14 who have not committed a felony are released from institutions without any rehabilitation or treatment options, and alternative forms of justice were included without evaluating their possibilities of application or their conditions for success. In addition, the economic status of most juvenile detainees continues to be one of the most important determining factors in the administration of justice

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

    Science.gov (United States)

    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.

  7. Transcriptional landscapes of Axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  9. 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.

  10. 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.

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

    Science.gov (United States)

    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.

  12. 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.

  13. 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  17. 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

  18. 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

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

    Science.gov (United States)

    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.

  20. 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  4. 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 ...

  5. 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.

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

    Science.gov (United States)

    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.

  7. Transgenesis in axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    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.

  8. 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.

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

    Science.gov (United States)

    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.

  10. Diffusion tensor tractography reveals muscle reconnection during axolotl limb regeneration.

    Directory of Open Access Journals (Sweden)

    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.

  11. 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  18. Novel axolotl cardiac function analysis method using magnetic resonance imaging

    NARCIS (Netherlands)

    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

  19. Novel axolotl cardiac function analysis method using magnetic resonance imaging

    NARCIS (Netherlands)

    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

  20. 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.

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

    Science.gov (United States)

    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

  2. Microarray Analysis of microRNA Expression during Axolotl Limb Regeneration

    Science.gov (United States)

    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

  3. 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.

  4. 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

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

    Science.gov (United States)

    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.

  6. 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  9. 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.

  10. 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.

  11. Axolotl cells and tissues enhances cutaneous wound healing in mice

    OpenAIRE

    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...

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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

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

    NARCIS (Netherlands)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  16. Comparison of tissue processing methods for microvascular visualization in axolotls.

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  1. 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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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

  4. "Changing for My Kid": Fatherhood Experiences of Mexican-Origin Teen Fathers Involved in the Justice System

    Science.gov (United States)

    Parra-Cardona, Jose Ruben; Sharp, Elizabeth A.; Wampler, Richard S.

    2008-01-01

    A descriptive phenomenological study was conducted with six adolescent fathers of Mexican origin on juvenile probation for a variety of serious offenses. All participants successfully completed a parenting program designed especially for teen fathers. In a series of consecutive in-depth interviews, teen fathers were asked to discuss their…

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  7. Brief report: An examination of the relationships between parental monitoring, self-esteem and delinquency among Mexican American male adolescents.

    Science.gov (United States)

    Caldwell, Roslyn M; Beutler, Larry E; An Ross, Sylvia; Clayton Silver, N

    2006-06-01

    The present study examined relationships between parental monitoring (mother and father), self-esteem, and delinquency among 95 adjudicated Mexican American male adolescents who were on probationary status with the juvenile justice system. Consistent with previous literature pertaining to familial processes and delinquency among the general adolescent population, findings from the current study revealed that parental monitoring was negatively associated with delinquency. In addition, self-esteem was shown to be positively correlated with delinquency. These results highlight the generalizability of previous research related to familial, emotional, and behavioral processes among Mexican American male adolescents.

  8. Mexican Perspectives on Mexican-U.S. Relations

    Science.gov (United States)

    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

  9. Axolotl/Bichos Raros Crónica

    Directory of Open Access Journals (Sweden)

    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.

  10. 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

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

    Science.gov (United States)

    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.

  12. 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...

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  15. 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...

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

    Science.gov (United States)

    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.

  17. Early regulation of axolotl limb regeneration.

    Science.gov (United States)

    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.

  18. Explanatory Emotion Talk in Mexican Immigrant and Mexican American Families.

    Science.gov (United States)

    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…

  19. 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...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

  6. 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.

  7. 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

  8. 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…

  9. 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

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  12. 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  15. 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

  16. 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

  17. Juvenile angiofibroma

    Science.gov (United States)

    Nasal tumor; Angiofibroma - juvenile; Benign nasal tumor; Juvenile nasal angiofibroma; JNA ... Juvenile angiofibroma is not very common. It is most often found in adolescent boys. The tumor contains many blood ...

  18. 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…

  19. 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

  20. 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.

  1. 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.

  2. Accuracy in the legal age estimation according to the third molars mineralization among Mexicans and Columbians.

    Science.gov (United States)

    Costa, José; Montero, Javier; Serrano, Sarai; Albaladejo, Alberto; López-Valverde, Antonio; Bica, Isabel

    2014-11-01

    This study aims to assess the accuracy of age estimation according to two cut-off points of Demirjian's developmental stages (G and H) in the wisdom teeth, using panoramic radiographs from Colombian and Mexican teenagers. The degree of maturation of the third molars was classified according to Demirjian in 8 stages (from A to H) by a blinded trained assessor. The sensitivity, specificity and efficacy of two cut-off points (G and H) were calculated for both samples. The orthopantomographies of 316 subjects, 171 Colombians (54.1%) and 145 Mexicans (45.9%), were analyzed. The stage H was found to be the best threshold for detecting juveniles (because the high specificity) in all the third molars assessed. The specificity was higher for lower third molars than for upper third molars, but no asymmetrical discrepancy was noted. The stage H is the best cut-off point for detecting the adulthood when a high-specificity test is required. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

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

    Science.gov (United States)

    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.

  4. 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.

  5. 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…

  6. 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.

  7. Juvenile rheumatoid arthritis

    Science.gov (United States)

    ... joints. This form of JIA may turn into rheumatoid arthritis. It may involve 5 or more large and ... no known prevention for JIA. Alternative Names Juvenile rheumatoid arthritis (JRA); Juvenile chronic polyarthritis; Still disease; Juvenile spondyloarthritis ...

  8. 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.

  9. 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…

  10. 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...

  11. 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.

  12. 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.

  13. 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.

  14. 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

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

    Science.gov (United States)

    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.

  16. 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.

  17. 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.

  18. Conceptualizing juvenile prostitution as child maltreatment: findings from the National Juvenile Prostitution Study.

    Science.gov (United States)

    Mitchell, Kimberly J; Finkelhor, David; Wolak, Janis

    2010-02-01

    Two studies were conducted to identify the incidence (Study 1) and characteristics (Study 2) of juvenile prostitution cases known to law enforcement agencies in the United States. Study 1 revealed a national estimate of 1,450 arrests or detentions (95% confidence interval [CI]: 1,287-1,614) in cases involving juvenile prostitution during a 1-year period. In Study 2, exploratory data were collected from a subsample of 138 cases from police records in 2005. The cases are broadly categorized into three main types: (a) third-party exploiters, (b) solo prostitution, and (c) conventional child sexual abuse (CSA) with payment. Cases were classified into three initial categories based on police orientation toward the juvenile: (a) juveniles as victims (53%), (b) juveniles as delinquents (31%), and (c) juvenile as both victims and delinquents (16%). When examining the status of the juveniles by case type, the authors found that all the juveniles in CSA with payment cases were treated as victims, 66% in third-party exploiters cases, and 11% in solo cases. Findings indicate law enforcement responses to juvenile prostitution are influential in determining whether such youth are viewed as victims of commercial sexual exploitation or as delinquents.

  19. 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.

  20. 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.

  1. 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.

  2. Juvenile Arthritis

    Science.gov (United States)

    Juvenile arthritis (JA) is arthritis that happens in children. It causes joint swelling, pain, stiffness, and loss of motion. It can affect any joint, but ... of JA that children get is juvenile idiopathic arthritis. There are several other forms of arthritis affecting ...

  3. What Is Juvenile Arthritis?

    Science.gov (United States)

    ... Initiative Breadcrumb Home Health Topics English Español Juvenile Arthritis Basics In-Depth Download Download EPUB Download PDF What is it? Points To Remember About Juvenile Arthritis Juvenile arthritis is the term used to describe ...

  4. 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.

  5. Juvenile Firesetting.

    Science.gov (United States)

    Peters, Brittany; Freeman, Bradley

    2016-01-01

    Juvenile firesetting is a significant cause of morbidity and mortality in the United States. Male gender, substance use, history of maltreatment, interest in fire, and psychiatric illness are commonly reported risk factors. Interventions that have been shown to be effective in juveniles who set fires include cognitive behavior therapy and educational interventions, whereas satiation has not been shown to be an effective intervention. Forensic assessments can assist the legal community in adjudicating youth with effective interventions. Future studies should focus on consistent assessment and outcome measures to create more evidence for directing evaluation and treatment of juvenile firesetters. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. 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…

  7. 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…

  8. 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.

  9. 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.…

  10. 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

  11. 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

  12. 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...

  13. Juvenile Court Statistics - 1972.

    Science.gov (United States)

    Office of Youth Development (DHEW), Washington, DC.

    This report is a statistical study of juvenile court cases in 1972. The data demonstrates how the court is frequently utilized in dealing with juvenile delinquency by the police as well as by other community agencies and parents. Excluded from this report are the ordinary traffic cases handled by juvenile court. The data indicate that: (1) in…

  14. Juvenile Court Statistics, 1974.

    Science.gov (United States)

    Corbett, Jacqueline; Vereb, Thomas S.

    This report presents information on juvenile court processing of youth in the U.S. during 1974. It is based on data gathered under the National Juvenile Court Statistical Reporting System. Findings can be summarized as follows: (1) 1,252,700 juvenile delinquency cases, excluding traffic offenses, were handled by courts in the U.S. in 1974; (2) the…

  15. THE STUDY OF FEATURES OF GUILT OF JUVENILE OFFENDERS IN THE CONTEXT OF JUVENILE JUSTICE

    Directory of Open Access Journals (Sweden)

    Natalija Vladimirovna Galkina

    2015-08-01

    Full Text Available The article is devoted to the results of empirical studies of the experiences of guilt of juvenile offenders in the context of juvenile justice where a minor appears as the subject of legal relations. Restorative approach of juvenile justice is based on an admission of guilt to the victim. In connection with it, the research of features of the guilt of minors who have committed an offence and the conditions for the development of the subjectivity will enhance understanding of the possibilities of restorative juvenile justice system in the prevention of juvenile delinquency.Thus, the results of empirical research presented in the article are important for determining of the psychological bases of realization of rehabilitation programs in the context of juvenile justice. In particular, the results are important for the organization and conduct of psychological work to overcome the psychological barriers in the behavior of juveniles having inherently maladaptive guilt and destructive psychological defense mechanisms.

  16. 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

  17. 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.

  18. Craniofacial Secular Change in Recent Mexican Migrants.

    Science.gov (United States)

    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

  19. Juvenile mammary papillomatosis; Papilomatosis juvenil mamaria

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, M.; Jimenez, A. V. [Hospital Reina Sofia. Cordoba (Spain)

    2001-07-01

    Juvenile mammary papillomatosis is a benign proliferative disease of young patients, generally under 30 years of age. The most frequent clinical presentation is the existence of an elastic and mobile lymph node of the breast. Anatomopathologically, it is characterized because it presents ductal epithelial hyperplasia, sometimes with marked atypia, and there are numerous cysts having different sizes among the findings. It has been associated with an increase in the incidence of breast cancer, both in the patient herself as well as her family. We review the literature on the subject and present the mammographic and ultrasonographic findings of a 22 year old woman diagnosed of juvenile mammary papillomatosis. (Author) 12 refs.

  20. 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…

  1. Juvenile giant fibroadenoma

    Directory of Open Access Journals (Sweden)

    Vipul Yagnik

    2011-07-01

    Full Text Available Fibroadenomas are benign solid tumor associated with aberration of normal lobular development. Juvenile giant fibroadenoma is usually single and >5 cm in size /or >500 gms in weight. Important differential diagnoses are: phyllodes tumor and juvenile gigantomastia. Simple excision is the treatment of choice.

  2. 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

  3. 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.

  4. 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)

  5. 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

  6. 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.)

  7. 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.

  8. Juvenile Idiopathic Arthritis

    Directory of Open Access Journals (Sweden)

    Kenan Barut

    2017-04-01

    Full Text Available Juvenile idiopathic arthritis is the most common chronic rheumatic disease of unknown aetiology in childhood and predominantly presents with peripheral arthritis. The disease is divided into several subgroups, according to demographic characteristics, clinical features, treatment modalities and disease prognosis. Systemic juvenile idiopathic arthritis, which is one of the most frequent disease subtypes, is characterized by recurrent fever and rash. Oligoarticular juvenile idiopathic arthritis, common among young female patients, is usually accompanied by anti-nuclear antibodie positivity and anterior uveitis. Seropositive polyarticular juvenile idiopathic arthritis, an analogue of adult rheumatoid arthritis, is seen in less than 10% of paediatric patients. Seronegative polyarticular juvenile idiopathic arthritis, an entity more specific for childhood, appears with widespread large- and small-joint involvement. Enthesitis-related arthritis is a separate disease subtype, characterized by enthesitis and asymmetric lower-extremity arthritis. This disease subtype represents the childhood form of adult spondyloarthropathies, with human leukocyte antigen-B27 positivity and uveitis but commonly without axial skeleton involvement. Juvenile psoriatic arthritis is characterized by a psoriatic rash, accompanied by arthritis, nail pitting and dactylitis. Disease complications can vary from growth retardation and osteoporosis secondary to treatment and disease activity, to life-threatening macrophage activation syndrome with multi-organ insufficiency. With the advent of new therapeutics over the past 15 years, there has been a marked improvement in juvenile idiopathic arthritis treatment and long-term outcome, without any sequelae. The treatment of juvenile idiopathic arthritis patients involves teamwork, including an experienced paediatric rheumatologist, an ophthalmologist, an orthopaedist, a paediatric psychiatrist and a physiotherapist. The primary goals

  9. 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.

  10. Parental Factors Associated with Mexican American Adolescent Alcohol Use

    Directory of Open Access Journals (Sweden)

    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.

  11. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  13. Historical aspects of Mexican psychiatry.

    Science.gov (United States)

    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.

  14. Juvenile angiofibromer

    DEFF Research Database (Denmark)

    Thuesen, Anne Daugaard; Jakobsen, John; Nepper-Rasmussen, Jørgen

    2005-01-01

    Juvenile angiofibroma is a rare, benign, rich vascular tumor, and approximately one new case is diagnosed in Denmark each year. It sits in the foramen sphenopalatinum and occurs in boys from 14 to 25 years of age. The most frequent initial symptoms are nasal obstruction and epistaxis. Through...... the years, the treatment of juvenile angiofibroma has included many methods, including surgical excision, electrocoagulation, interstitial or external radiation therapy, cryosurgery, hormone administration and chemotherapy. Radiation, chemotherapy and surgery have proven to be the most effective treatments...

  15. Parenting and juvenile delinquency

    NARCIS (Netherlands)

    Hoeve, M.

    2008-01-01

    Juvenile delinquency is a noteworthy problem. This thesis addressed the association between parenting and juvenile delinquency by analyzing the concepts of parenting adopted in family research in relation to criminological concepts and measures of delinquent behavior. Four studies were conducted.

  16. 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.

  17. 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

  18. 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)

  19. Juvenile delinquency and correctional treatment in Britain

    OpenAIRE

    堀尾, 良弘; ホリオ, ヨシヒロ; Yoshihiro, Horio

    2006-01-01

    Japanese modernistic culture is influenced not a little from Britain. In looking at the Juvenile Law and the history of correctional treatment in Britain, understanding of today's juvenile delinquency and treatment deepen. Moreover, the background and issue of juvenile delinquency in Britain are also discussed. As a feature of the juvenile delinquency in Britain, the common field with Japan and the field peculiar to Britain became clear in each. It is common to the world that the juvenile del...

  20. Juvenile prison in parallel legislation

    Directory of Open Access Journals (Sweden)

    Lutovac Mitar

    2016-01-01

    Full Text Available The need for punishment of juveniles occurred from the time when there was no clear line separating them from the adult criminal population. At the same time, the evolution of the juvenile punishment is not in itself involve substantial changes to their criminal status. On the contrary, the status of minors in society did not show serious differences regarding the status of young adults, as well as the adult elderly. On the other hand, on the ground of their punishment is recorded deviations that go in the direction of application of mild corporal punishment. Closing the minor was performed in a physically separate parts of the general penal institutions with the use of a lower degree of restrictions while serving juvenile prison. Due to the different treatment of minors during the evolution of their criminal status leads to their different treatment in comparative law. That is why we are witnessing the existence of numerous differences in the juvenile punishment in some countries in the world. On the European continent there is a wide range of different legal solutions when it comes to punishing juveniles. There are considerable differences in the procedure pronouncing juvenile prison and in particular penal treatment of juveniles in penitentiary institutions. For these reasons, the author has decided to show the basic statutory provisions in the part that relates to the issue of punishment of minors in the legislation of individual countries.

  1. 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

  2. Bilateral, independent juvenile nasopharyngeal angiofibroma

    DEFF Research Database (Denmark)

    Mørkenborg, Marie-Louise; Frendø, M; Stavngaard, T

    2015-01-01

    BACKGROUND: Juvenile nasopharyngeal angiofibroma is a benign, vascular tumour that primarily occurs in adolescent males. Despite its benign nature, aggressive growth patterns can cause potential life-threatening complications. Juvenile nasopharyngeal angiofibroma is normally unilateral, originating...... from the sphenopalatine artery, but bilateral symptoms can occur if a large tumour extends to the contralateral side of the nasopharynx. This paper presents the first reported case of true bilateral extensive juvenile nasopharyngeal angiofibroma involving clinically challenging pre-surgical planning...... embolisation. Radical removal performed as one-step, computer-assisted functional endoscopic sinus surgery was performed. The follow-up period was uncomplicated. CONCLUSION: This case illustrates the importance of suspecting bilateral juvenile nasopharyngeal angiofibroma in patients presenting with bilateral...

  3. Criminal Profiles of Violent Juvenile Sex and Violent Juvenile Non-Sex Offenders: An Explorative Longitudinal Study

    Science.gov (United States)

    van Wijk, Anton Ph.; Mali, Bas R. F.; Bullens, Ruud A. R.; Vermeiren, Robert R.

    2007-01-01

    Few studies have longitudinally investigated the criminal profiles of violent juvenile sex and violent juvenile non-sex offenders. To make up for this lack, this study used police records of juveniles to determine the nature of the criminal profiles of violent sex offenders (n = 226) and violent non-sex offenders (n = 4,130). All offenders…

  4. A Turnover Model for the Mexican Maquiladoras.

    Science.gov (United States)

    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)

  5. Juvenile morphology in baleen whale phylogeny.

    Science.gov (United States)

    Tsai, Cheng-Hsiu; Fordyce, R Ewan

    2014-09-01

    Phylogenetic reconstructions are sensitive to the influence of ontogeny on morphology. Here, we use foetal/neonatal specimens of known species of living baleen whales (Cetacea: Mysticeti) to show how juvenile morphology of extant species affects phylogenetic placement of the species. In one clade (sei whale, Balaenopteridae), the juvenile is distant from the usual phylogenetic position of adults, but in the other clade (pygmy right whale, Cetotheriidae), the juvenile is close to the adult. Different heterochronic processes at work in the studied species have different influences on juvenile morphology and on phylogenetic placement. This study helps to understand the relationship between evolutionary processes and phylogenetic patterns in baleen whale evolution and, more in general, between phylogeny and ontogeny; likewise, this study provides a proxy how to interpret the phylogeny when fossils that are immature individuals are included. Juvenile individuals in the peramorphic acceleration clades would produce misleading phylogenies, whereas juvenile individuals in the paedomorphic neoteny clades should still provide reliable phylogenetic signals.

  6. Larval, pre-juvenile and juvenile development of Diapterus peruvianus (Perciformes: Gerreidae

    Directory of Open Access Journals (Sweden)

    Sylvia Patricia Adelheid Jiménez Rosenberg

    2003-06-01

    Full Text Available The development of Diapterus peruvianus (Sauvage 1879 is based on 60 larvae collected in superficial tows made in Bahía Concepción, and on 16 prejuvenile and juvenile organisms collected in Bahía de La Paz, B. C. S., México, using a standard plankton net and a rectangular epibenthonic net, respectively. Larvae of D. peruvianus show three large blotches on the dorsum of the gut that can fuse together and give the appearance of one large continuous blotch. There are two to three pre-anal pigments and 16 post-anal pigments in the ventral midline; cephalic pigments are present from the postflexion stage, as well as a serrated preoperculum. The prejuvenile and juvenile organisms are distinguished by their body depth, the analfin formula, the serrated preoperculum and the base pigments in the dorsal and anal fins.El desarrollo de Diapterus peruvianus se analizó con base en 60 larvas recolectadas en Bahía Concepción y 16 pre-juveniles y juveniles recolectados en la Ensenada de La Paz, B. C. S. México, usando respectivamente, una red estándar de plancton en arrastres superficiales y una red epibentónica para arrastres de plancton. Las larvas presentan desde la pre-flexión tres manchas alargadas sobre la superficie dorsal de la masa visceral, que pueden unirse y dar apariencia de pigmentación continua, observándose hasta 16 pigmentos post-anales en la línea media ventral y de dos a tres pigmentos pre-anales; la pigmentación cefálica así como la forma aserrada del pre-opérculo característica del género, aparecen a partir de la post-flexión. Los organismos pre-juveniles y juveniles se distinguen por la profundidad del cuerpo, la fórmula de la aleta anal, la fina forma aserrada del pre-opérculo y la pigmentación en la base de las aletas dorsal y anal.

  7. Familism, machismo and child rearing practices among Mexican Americans.

    Science.gov (United States)

    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

  8. 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.

  9. Juvenile Residential Facility Census, 2010: Selected Findings. Juvenile Offenders and Victims: National Report Series. Bulletin NCJ 241134

    Science.gov (United States)

    Hockenberry, Sarah; Sickmund, Melissa; Sladky, Anthony

    2013-01-01

    This bulletin is part of the "Juvenile Offenders and Victims National Report Series." The "National Report" offers a comprehensive statistical overview of the problems of juvenile crime, violence, and victimization and the response of the juvenile justice system. During each interim year, the bulletins in the "National…

  10. 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...

  11. Juvenile Confinement in Context

    Science.gov (United States)

    Mendel, Richard A.

    2012-01-01

    For more than a century, the predominant strategy for the treatment and punishment of serious and sometimes not-so-serious juvenile offenders in the United States has been placement into large juvenile corrections institutions, alternatively known as training schools, reformatories, or youth corrections centers. America's heavy reliance on…

  12. [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

  13. "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…

  14. Juvenile Angiofibroma: Evolution of Management

    Science.gov (United States)

    Nicolai, Piero; Schreiber, Alberto; Bolzoni Villaret, Andrea

    2012-01-01

    Juvenile angiofibroma is a rare benign lesion originating from the pterygopalatine fossa with distinctive epidemiologic features and growth patterns. The typical patient is an adolescent male with a clinical history of recurrent epistaxis and nasal obstruction. Although the use of nonsurgical therapies is described in the literature, surgery is currently considered the ideal treatment for juvenile angiofibroma. Refinement in preoperative embolization has provided significant reduction of complications and intraoperative bleeding with minimal risk of residual disease. During the last decade, an endoscopic technique has been extensively adopted as a valid alternative to external approaches in the management of small-intermediate size juvenile angiofibromas. Herein, we review the evolution in the management of juvenile angiofibroma with particular reference to recent advances in diagnosis and treatment. PMID:22164185

  15. Juvenile Angiofibroma: Evolution of Management

    Directory of Open Access Journals (Sweden)

    Piero Nicolai

    2012-01-01

    Full Text Available Juvenile angiofibroma is a rare benign lesion originating from the pterygopalatine fossa with distinctive epidemiologic features and growth patterns. The typical patient is an adolescent male with a clinical history of recurrent epistaxis and nasal obstruction. Although the use of nonsurgical therapies is described in the literature, surgery is currently considered the ideal treatment for juvenile angiofibroma. Refinement in preoperative embolization has provided significant reduction of complications and intraoperative bleeding with minimal risk of residual disease. During the last decade, an endoscopic technique has been extensively adopted as a valid alternative to external approaches in the management of small-intermediate size juvenile angiofibromas. Herein, we review the evolution in the management of juvenile angiofibroma with particular reference to recent advances in diagnosis and treatment.

  16. [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.

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

    Directory of Open Access Journals (Sweden)

    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.

  18. 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 ...

  19. 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

  20. 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.

  1. Evaluation of the effects of the metals Cd, Cr, Pb and their mixture on the filtration and oxygen consumption rates in catarina scallop, Argopecten ventricosus juveniles.

    Science.gov (United States)

    Sobrino-Figueroa, Alma S; Cáceres-Martinez, Carlos

    2014-01-01

    In this work, we evaluated the effect of sublethal concentrations ( LC25, LC10 and LC5) of cadmium, chromium, lead, and their mixture on the filtration rate and oxygen consumption rate of Catarina scallop, Argopecten ventricosus (Sowerby, 1842), juveniles, in order to evaluate the use of these biomarkers as a reliable tool in environmental monitoring studies, because these metals have been found at high levels in water and sediments in the Mexican Pacific systems. An inverse dose-response relationship was observed when metal concentration and exposure time increased, the filtration rate and oxygen consumption rate reduced. The physiological responses evaluated in this study were sufficiently sensitive to detect alterations in the organisms at 0.014 mg l(-1) Cd, 0.311 mg l(-1) Cr, 0.125 mg l(-1) Pb and 0.05 mg l(-1) Cd + Cr + Pb at 24 and 72 hrs. Cd showed the most drastic effect. The Catarina scallop juveniles were more sensitive to Cd, Cr and Pb as compared to other bivalves. The biomarkers evaluated are a reliable tool to carry out environmental monitoring studies.

  2. Juvenile polyposis syndrome

    OpenAIRE

    Hsiao, Yi-Han; Wei, Chin-Hung; Chang, Szu-Wen; Chang, Lung; Fu, Yu-Wei; Lee, Hung-Chang; Liu, Hsuan-Liang; Yeung, Chun-Yan

    2016-01-01

    Abstract Background: Juvenile polyposis syndrome, a rare disorder in children, is characterized with multiple hamartomatous polyps in alimentary tract. A variety of manifestations include bleeding, intussusception, or polyp prolapse. In this study, we present an 8-month-old male infant of juvenile polyposis syndrome initially presenting with chronic anemia. To the best of our knowledge, this is the youngest case reported in the literature. Methods: We report a rare case of an 8-month-old male...

  3. Stress Resilience among Border Mexican American Women

    Science.gov (United States)

    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…

  4. Social and psychological aspects of criminal juvenile justice in the world practice (Anglo-Saxon model of juvenile justice

    Directory of Open Access Journals (Sweden)

    D.S. Oshevsky

    2013-10-01

    Full Text Available The article is the final part of the review of existing foreign models of juvenile criminal justice system. We analyze the principles of juvenile justice in the criminal trial: protective orientation, personalization and social richness of the trial, the emphasis on educational influences. We present the foreign experience of incorporating social, psychological and clinical special knowledge into specialized justice concerning juvenile offenders. We analyze modern trends in the development of juvenile justice in the United States and Canada. We present material related to methods of risk assessment of re-offending among adolescents. We highlight approaches to complex long-term follow-up of juvenile offenders in Anglo-Saxon juvenile justice. We describe some aspects of the probation service using the method of case management. In the context of the accepted “National Strategy for Action for the Benefit of Children for 2012-2017”, the prospects for the development of specialized criminal justice for young offenders in the Russian Federation are discussed

  5. Juvenile polyposis syndrome

    Science.gov (United States)

    Hsiao, Yi-Han; Wei, Chin-Hung; Chang, Szu-Wen; Chang, Lung; Fu, Yu-Wei; Lee, Hung-Chang; Liu, Hsuan-Liang; Yeung, Chun-Yan

    2016-01-01

    Abstract Background: Juvenile polyposis syndrome, a rare disorder in children, is characterized with multiple hamartomatous polyps in alimentary tract. A variety of manifestations include bleeding, intussusception, or polyp prolapse. In this study, we present an 8-month-old male infant of juvenile polyposis syndrome initially presenting with chronic anemia. To the best of our knowledge, this is the youngest case reported in the literature. Methods: We report a rare case of an 8-month-old male infant who presented with chronic anemia and gastrointestinal bleeding initially. Panendoscopy and abdominal computed tomography showed multiple polyposis throughout the entire alimentary tract leading to intussusception. Technetium-99m-labeled red blood cell (RBC) bleeding scan revealed the possibility of gastrointestinal tract bleeding in the jejunum. Histopathological examination on biopsy samples showed Peutz-Jeghers syndrome was excluded, whereas the diagnosis of juvenile polyposis syndrome was established. Results: Enteroscopic polypectomy is the mainstay of the treatment. However, polyps recurred and occupied the majority of the gastrointestinal tract in 6 months. Supportive management was given. The patient expired for severe sepsis at the age of 18 months. Conclusion: Juvenile polyposis syndrome is an inherited disease, so it is not possible to prevent it. Concerning of its poor outcome and high mortality rate, it is important that we should increase awareness and education of the parents at its earliest stages. PMID:27631205

  6. Acupuntura em adolescentes com fibromialgia juvenil Acupuntura en adolescentes con fibromialgia juvenil Acupuncture in adolescents with juvenile fibromyalgia

    Directory of Open Access Journals (Sweden)

    Marialda Höfling P. Dias

    2012-01-01

    Full Text Available OBJETIVO: Descrever a utilização da acupuntura em adolescentes com fibromialgia juvenil. MÉTODOS: Estudo retrospectivo realizado em pacientes com fibromialgia juvenil (critérios do Colégio Americano de Reumatologia submetidos a, pelo menos, 11 sessões semanais de acupuntura. As avaliações antes e após acupuntura incluíram dados demográficos, características da dor musculoesquelética, número de pontos dolorosos (NPD, escala visual analógica (EVA de dor, algiometria e índice miálgico (IM. Durante o estudo, os pacientes puderam usar analgésicos, amitriptilina e foram orientados a praticar atividade física aeróbica. Os resultados antes e após acupuntura foram comparados pelo teste não paramétrico de Wilcoxon. RESULTADOS: Dos 38 pacientes com fibromialgia juvenil acompanhados em oito anos consecutivos, 13 tinham todas as informações nos prontuários e nas fichas de acupuntura e foram avaliados. Destes 13, sete obtiveram melhora nos três parâmetros analisados (número de pontos dolorosos, EVA de dor e IM. As medianas do número de pontos dolorosos e da EVA de dor foram significativamente maiores antes do tratamento quando comparados ao final do tratamento com as sessões de acupuntura [14 (11-18 versus 10 (0-15, p=0,005; 6 (2-10 versus 3 (0-10, p=0,045; respectivamente]. Em contraste, a mediana do IM foi significativamente menor antes do tratamento [3,4 (2,49-4,39 versus 4,2 (2,71-5,99, p=0,02]. Nenhum dos pacientes com fibromialgia juvenil apresentou eventos adversos associados à acupuntura. CONCLUSÕES: Acupuntura é uma modalidade de Medicina Tradicional Chinesa que pode ser utilizada nos pacientes pediátricos com fibromialgia. Futuros estudos controlados serão necessários.OBJETIVO: Describir el uso de acupuntura en adolescentes con fibromialgia juvenil. MÉTODOS: Estudio retrospectivo realizado en pacientes con fibromialgia juvenil (criterios del Colegio Americano de Reumatología sometidos a al menos 11 sesiones

  7. 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.

  8. 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

  9. 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.

  10. Juvenile dispersal in Calomys venustus (Muridae: Sigmodontinae)

    Science.gov (United States)

    Priotto, José; Steinmann, Andrea; Provensal, Cecilia; Polop, Jaime

    2004-05-01

    Both spacing behaviour and dispersal movement are viewed as hierarchical processes in which the effects may be expressed at spatial scale. This research was carried out to examine the hypothesis that the presence of parents promotes the dispersal of juveniles from their natal nest and their father or mother home-range, in Calomys venustus.The study was carried out in four 0.25 ha fences (two controls and two experimentals), in a natural pasture. This study had two periods: Father Removal (FR) (August and December 1997; year one) and Mother Removal (MR) (August 1998 and January 1999; year two). For the FR treatment fathers were removed after juveniles were born, but in the MR treatment mothers were removed after the juveniles were weaned. The effect of parents on the dispersal distance of juveniles was analysed with respect to their natal nest and their mother and father home-range. Dispersal distance from the nest of C. venustus was independent of either male or female parent. Juveniles were more dispersing in relation to the centre of activity of their mothers than to that of their fathers, and females were more dispersing than males. Female juveniles overlap their home-range with their parents less than male juveniles do. The differences observed between female and male juveniles would be related to their different sexual maturation times, as well as to the female territoriality.

  11. Essential habitat for sardine juveniles in Iberian waters

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    Sílvia Rodríguez-Climent

    2017-09-01

    Full Text Available In a period when the Iberian sardine stock abundance is at its historical minimum, knowledge of the sardine juvenile’s distribution is crucial for the development of fishery management strategies. Generalized additive models were used to relate juvenile sardine presence with geographical variables and spawning grounds (egg abundance and to model juvenile abundance with the concurrent environmental conditions. Three core areas of juvenile distribution were identified: the Northern Portuguese shelf (centred off Aveiro, the coastal region in the vicinity of the Tagus estuary, and the eastern Gulf of Cadiz. Spatial differences in the relationship between juvenile presence and egg abundances suggest that essential juvenile habitat might partially differ from the prevailing spawning grounds. Models also depicted significant relationships between juvenile abundance, temperature and geographical variables in combination with salinity in the west and with zooplankton in the south. Results indicate that the sardine juvenile distribution along the Iberian Peninsula waters are an outcome of a combination of dynamic processes occurring early in life, such as egg and larva retention, reduced mortality and favourable feeding grounds for both larvae and juveniles.

  12. 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.

  13. 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.

  14. Juvenile offenders: competence to stand trial.

    Science.gov (United States)

    Soulier, Matthew

    2012-12-01

    This article details the legal background and assists the reader in the preparation and practical conduct of evaluations regarding juvenile adjudicative competency. The material is presented to be useful as a guide to direct questions of competency and covers aspects of evaluation that include: legal standard for competency to stand trial, developmental immaturity, current practice in juvenile competency to stand trial, forensic evaluation of juvenile competency to stand trial, organizing the evaluation, collateral sources of information, psychiatric evaluation of juvenile adjudicative competency, assessment of mental disorder and intellectual disability, assessment of developmental status, assessment of functional abilities for adjudicative competence, and reaching the forensic opinion. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Parenting and juvenile delinquency

    OpenAIRE

    Hoeve, M.

    2008-01-01

    Juvenile delinquency is a noteworthy problem. This thesis addressed the association between parenting and juvenile delinquency by analyzing the concepts of parenting adopted in family research in relation to criminological concepts and measures of delinquent behavior. Four studies were conducted. The first study addressed a meta-analysis on parenting characteristics and styles in relation to delinquency. In this meta-analysis, previous manuscripts were systematically analyzed, computing mean ...

  16. PSYCHOSOCIAL PROFILE OF JUVENILE DIABETES

    Science.gov (United States)

    Dass, Jyoti; Dhavale, H.S.; Rathi, Anup

    1999-01-01

    A study of the complex relationships between the patient characteristics, family and environmental influences, physician's behaviour and the demands of the disease with its management in Juvenile Diabetics was taken up at a general hospital. 90 subjects were selected for the study and grouped into three. Group A consisted of 30 Juvenile Diabetics, Group B of 30 Adult Diabetics and Group C of 30 Normal healthy adolescents. The impact of the illness was measured on the Diabetes Impact Measurement Scale (DIMS), the behavioural deviations and the parental attitudes towards child rearing on the Fallstrom's Questionnaire (FQ) and the family environment on the Family Climate Scale (FCS). Psychiatric morbidity was assessed using DSM-IV criteria. Group A & B were compared on the DIMS and Group A & C on FQ & FCS. Adult diabetics had a greater impact of diabetes. Juvenile diabetics had significantly higher frequency of behavioural deviations as compared to controls. Also there was a higher number of responses on questions indicating an overprotecting attitude amongst parents of juvenile diabetics. There was an increased incidence of psychiatric morbidity in juvenile diabetics as compared to normal adolescents irrespective of the family environment. The results are discussed in relation to current literature. PMID:21430802

  17. 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…

  18. 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.

  19. Juvenile Prostitution.

    Science.gov (United States)

    Csapo, Marg

    1986-01-01

    Recent research and Canadian government committee reports concerning juvenile prostitution are reviewed. Proposals are made in the realms of law and social policy; and existing programs are described. (DB)

  20. 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.

  1. 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

  2. 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…

  3. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  9. 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.

  10. Imágenes juveniles, medios y nuevos escenarios

    Directory of Open Access Journals (Sweden)

    Oscar Aguilera Ruiz

    2015-01-01

    Full Text Available Este artículo nace del análisis de los discursos radiales producidos exclusivamente para jóvenes en Santiago de Chile. Aborda además las categorías comprensivas de la vida juvenil, la vida juvenil de los años 90, el imaginario juvenil des-simbolizado, hacia una comprensión de lo juvenil, dinámica social propuesta por los medios y estrategias comunicacionales.

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

    Science.gov (United States)

    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.

  12. 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

  13. A review of the Mexican national innovation system

    Directory of Open Access Journals (Sweden)

    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

  14. 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

  15. Vegetative propagation of mature and juvenile northern red oak

    Science.gov (United States)

    James J. Zaczek; K. C. Steiner; C. W., Jr. Heuser

    1993-01-01

    Rooting trials were established to evaluate rooting success of cuttings from mature and juvenile, grafted and ungrafted northern red oak (NRO). Buds from 4 mature NRO ortets and juvenile seedlings were grafted onto juvenile and mature rootstock. Cuttings were collected from the grafts and from juvenile and mature shoots developed in situ and...

  16. Antibodies in juvenile-onset myositis.

    Science.gov (United States)

    Tansley, Sarah L

    2016-11-01

    Juvenile-onset myositis is a highly heterogeneous disease. Myositis-specific and associated autoantibodies provide a potential means of subdividing patients into clinically homogenous subgroups. Given the increasing availability of autoantibody testing, this review explores the phenotypes associated with different autoantibodies in juvenile-onset myositis and the potential clinical utility of autoantibody testing. Autoantibodies can be identified in 60-70% of children with myositis and the recent discovery of novel myositis-associated autoantibodies in adult patients suggests this may increase in the near future. Detailed phenotype descriptions are now known for several autoantibodies commonly identified in juvenile-onset disease. Whilst there is insufficient evidence to recommend a differential treatment approach based on autoantibody status, it is becoming increasingly clear that some autoantibody subgroups are often treatment resistant and may benefit from a more aggressive approach. The validation of nonspecialised methods for myositis-specific autoantibody detection should lead to more widely available testing. In juvenile-onset disease, this will provide detailed prognostic information and in the future may also influence approach.

  17. 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…

  18. REFORMATIONS IN ZIMBABWE'S JUVENILE JUSTICE SYSTEM

    African Journals Online (AJOL)

    Mugumbate

    1996-05-23

    May 23, 1996 ... The article is based on a desk review of existing literature on juvenile crime in the country. ... that Zimbabwe's juvenile justice system is transforming from being ... recommendations include expanding the Pre-trial Diversion ...

  19. 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

  20. 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...

  1. 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…

  2. 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…

  3. 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…

  4. 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

  5. Invisible Infantry: Mexicans in World War II

    Directory of Open Access Journals (Sweden)

    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.

  6. A Practical Approach to Juvenile Dermatomyositis and Juvenile Scleroderma.

    Science.gov (United States)

    McCann, Liza J; Pain, Clare E

    2016-02-01

    Juvenile dermatomyositis and juvenile scleroderma are rare multisystem autoimmune disorders. Although they share some pathognomonic hallmarks with adult onset myositis or scleroderma, there are significant differences in presentation, characteristics and associated features when the diseases present in childhood. In view of this, and the rarity of the conditions, it is important for care to be led by teams with expertise in pediatric rheumatology conditions. Prognosis has improved significantly in the West; likely due to early diagnosis and aggressive treatment with immunosuppressive medications. However, this trend is not replicated in the developing world. Early recognition of these diseases is crucial to achieve rapid and sustained remission and prevent disease or medication associated complications. This article aims to provide a practical overview for recognition, diagnosis and treatment of these conditions.

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

    Science.gov (United States)

    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…

  8. Adolescent neglect, juvenile delinquency and the risk of recidivism.

    Science.gov (United States)

    Ryan, Joseph P; Williams, Abigail B; Courtney, Mark E

    2013-03-01

    Victims of child abuse and neglect are at an increased risk of involvement with the juvenile justice and adult correctional systems. Yet, little is known about the continuation and trajectories of offending beyond initial contact with law enforcement. Neglect likely plays a critical role in continued offending as parental monitoring, parental rejection and family relationships are instrumental in explaining juvenile conduct problems. This study sought to determine whether neglect is associated with recidivism for moderate and high risk juvenile offenders in Washington State. Statewide risk assessments and administrative records for child welfare, juvenile justice, and adult corrections were analyzed. The sample was diverse (24 % female, 13 % African American, 8 % Hispanic, 5 % Native American) and included all moderate and high risk juvenile offenders screened by juvenile probation between 2004 and 2007 (n = 19,833). Official records from child protection were used to identify juvenile offenders with a history of child neglect and to identify juvenile offenders with an ongoing case of neglect. Event history models were developed to estimate the risk of subsequent offending. Adolescents with an ongoing case neglect were significantly more likely to continue offending as compared with youth with no official history of neglect. These findings remain even after controlling for a wide range of family, peer, academic, mental health, and substance abuse covariates. Interrupting trajectories of offending is a primary focus of juvenile justice. The findings of the current study indicate that ongoing dependency issues play a critical role in explaining the outcomes achieved for adolescents in juvenile justice settings. The implications for improved collaboration between child welfare and juvenile justice are discussed.

  9. Do juveniles bully more than young offenders?

    Science.gov (United States)

    Ireland, Jane L

    2002-04-01

    This study compares bullying behaviour among juvenile and young offenders and incorporates two different methods to measure bullying. Ninety-five male juvenile and 196 male young offenders completed two questionnaires, one that measured bullying directly and one that measured behaviours indicative of "being bullied" or of "bullying others". Juveniles perceived a higher extent of bullying than young offenders. Juveniles reported significantly more physical, psychological or verbal and overall direct forms of bullying behaviour than young offenders. A number of differences were found between juveniles and young offenders with regard to the types of prisoners likely to become victims, who they would advise a victim to speak to and how bullying could be prevented. The results are discussed in relation to developmental theories of aggression and how bullying behaviour can be defined and measured among prisoners. Copyright 2002 The Association for Professionals in Services for Adolescents. Published by Elsevier Science Ltd. All rights reserved.

  10. An unusual presentation of juvenile lupus nephritis

    Directory of Open Access Journals (Sweden)

    Malleshwar Bottu

    2016-01-01

    Full Text Available The incidence of juvenile lupus varies widely ranging between 4 and 250 per 100,000 population. Most common organ involvement in juvenile lupus is kidney. Neurological, cutaneous and hematological involvements are also involved. Skeletal muscle involvement in the form of myositis is rare. Myositis as presenting manifestation in juvenile lupus is also unusual. Herein, we report one such case wherein myositis preceded the onset of lupus nephritis

  11. Laser capture microdissection of gonads from juvenile zebrafish

    DEFF Research Database (Denmark)

    Jørgensen, Anne; Nielsen, John; Morthorst, Jane Ebsen

    2009-01-01

    was adjusted and optimised to isolate juvenile zebrafish gonads. Results: The juvenile zebrafish gonad is not morphologically distinguishable when using dehydrated cryosections on membrane slides and a specific staining method is necessary to identify the gonads. The protocol setup in this study allows......Background: Investigating gonadal gene expression is important in attempting to elucidate the molecular mechanism of sex determination and differentiation in the model species zebrafish. However, the small size of juvenile zebrafish and correspondingly their gonads complicates this type...... of investigation. Furthermore, the lack of a genetic sex marker in juvenile zebrafish prevents pooling gonads from several individuals. The aim of this study was to establish a method to isolate the gonads from individual juvenile zebrafish allowing future investigations of gonadal gene expression during sex...

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

    Directory of Open Access Journals (Sweden)

    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.

  13. 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

  14. Extending juvenility in grasses

    Energy Technology Data Exchange (ETDEWEB)

    Kaeppler, Shawn; de Leon Gatti, Natalia; Foerster, Jillian

    2017-04-11

    The present invention relates to compositions and methods for modulating the juvenile to adult developmental growth transition in plants, such as grasses (e.g. maize). In particular, the invention provides methods for enhancing agronomic properties in plants by modulating expression of GRMZM2G362718, GRMZM2G096016, or homologs thereof. Modulation of expression of one or more additional genes which affect juvenile to adult developmental growth transition such as Glossy15 or Cg1, in conjunction with such modulation of expression is also contemplated. Nucleic acid constructs for down-regulation of GRMZM2G362718 and/or GRMZM2G096016 are also contemplated, as are transgenic plants and products produced there from, that demonstrate altered, such as extended juvenile growth, and display associated phenotypes such as enhanced yield, improved digestibility, and increased disease resistance. Plants described herein may be used, for example, as improved forage or feed crops or in biofuel production.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. 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.

  17. 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.

  18. 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…

  19. 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)

  20. 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.

  1. Law & psychiatry: punishing juveniles who kill.

    Science.gov (United States)

    Appelbaum, Paul S

    2012-10-01

    Punishment of juvenile murderers forces policy makers to weigh the developmental immaturity of adolescents against the heinousness of their crimes. The U.S. Supreme Court has progressively limited the severity of punishments that can be imposed on juveniles, holding that their impulsivity, susceptibility to peer pressure, and more fluid character render them less culpable for their actions. Having eliminated the death penalty as a punishment, the Court recently struck down mandatory life sentences without prospect of parole. The decision is interesting for its emphasis on rehabilitation, opening the door to further restrictions on punitive sentences for juveniles-and perhaps for adults too.

  2. 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.

  3. 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.

  4. 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…

  5. Development of consensus treatment plans for juvenile localized scleroderma: a roadmap toward comparative effectiveness studies in juvenile localized scleroderma.

    Science.gov (United States)

    Li, Suzanne C; Torok, Kathryn S; Pope, Elena; Dedeoglu, Fatma; Hong, Sandy; Jacobe, Heidi T; Rabinovich, C Egla; Laxer, Ronald M; Higgins, Gloria C; Ferguson, Polly J; Lasky, Andrew; Baszis, Kevin; Becker, Mara; Campillo, Sarah; Cartwright, Victoria; Cidon, Michael; Inman, Christi J; Jerath, Rita; O'Neil, Kathleen M; Vora, Sheetal; Zeft, Andrew; Wallace, Carol A; Ilowite, Norman T; Fuhlbrigge, Robert C

    2012-08-01

    Juvenile localized scleroderma (LS) is a chronic inflammatory skin disorder associated with substantial morbidity and disability. Although a wide range of therapeutic strategies has been reported in the literature, a lack of agreement on treatment specifics and accepted methods for clinical assessment has made it difficult to compare approaches and identify optimal therapy. Our objective was to develop standardized treatment plans, clinical assessments, and response criteria for active, moderate to high severity juvenile LS. A core group of pediatric rheumatologists, dermatologists, and a lay advisor was engaged by the Childhood Arthritis and Rheumatology Research Alliance (CARRA) to develop standardized treatment plans and assessment parameters for juvenile LS using consensus methods/nominal group techniques. Recommendations were validated in 2 face-to-face conferences with a larger group of practitioners with expertise in juvenile LS and with the full membership of CARRA, which encompasses the majority of pediatric rheumatologists in the US and Canada. Consensus was achieved on standardized treatment plans that reflect the prevailing treatment practices of CARRA members. Standardized clinical assessment methods and provisional treatment response criteria were also developed. Greater than 90% of pediatric rheumatologists responding to a survey (66% of CARRA membership) affirmed the final recommendations and agreed to utilize these consensus plans to treat patients with juvenile LS. Using consensus methodology, we have developed standardized treatment plans and assessment methods for juvenile LS. The high level of support among pediatric rheumatologists will support future comparative effectiveness studies and enable the development of evidence-based guidelines for the treatment of juvenile LS. Copyright © 2012 by the American College of Rheumatology.

  6. The semantic sphere of juvenile offenders

    Directory of Open Access Journals (Sweden)

    Oshevsky D.S.

    2017-01-01

    Full Text Available The article presents the results of a preliminary empirical study aimed to identify features of the semantic sphere of adolescents who have committed illegal, including aggressive acts. The study included 50 male juveniles aged of 16 - 17 years. The first group consisted of adolescents convicted of aggressive and violent crimes; the second – of property socially dangerous acts (SDA. It is shown that evaluation of such adolescents is generally categorical and polar, the semantic field is subdifferentiable, less hierarchic, and has not enough realistic structure of meanings. Developed structure of motives and meanings is the basis of voluntary regulation of socially significant behavior. Thus, assessing the semantic sphere of juvenile offenders we can highlight its characteristics as risk factors of unlawful behavior, as well as the resource side, that will contribute to addressing issues of prevention and correction of unlawful behavior. Key words: juvenile offenders, semantic field of juvenile offenders, unlawful behavior.

  7. 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...

  8. 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

  9. Differential heritability of adult and juvenile antisocial traits.

    Science.gov (United States)

    Lyons, M J; True, W R; Eisen, S A; Goldberg, J; Meyer, J M; Faraone, S V; Eaves, L J; Tsuang, M T

    1995-11-01

    Studies of adult antisocial behavior or criminality usually find genetic factors to be more important than the family environment, whereas studies of delinquency find the family environment to be more important. We compared DSM-III-R antisocial personality disorder symptoms before vs after the age of 15 years within a sample of twins, rather than comparing across studies. We administered the Diagnostic Interview Schedule Version III-revised by telephone to 3226 pairs of male twins from the Vietnam Era Twin Registry. Biometrical modeling was applied to each symptom of antisocial personality disorder and summary measures of juvenile and adult symptoms. Five juvenile symptoms were significantly heritable, and five were significantly influenced by the shared environment. Eight adult symptoms were significantly heritable, and one was significantly influenced by the shared environment. The shared environment explained about six times more variance in juvenile anti-social traits than in adult traits. Shared environmental influences on adult antisocial traits overlapped entirely with those on juvenile traits. Additive genetic factors explained about six times more variance in adult vs juvenile traits. The juvenile genetic determinants overlapped completely with genetic influences on adult traits. The unique environment (plus measurement error) explained the largest proportion of variance in both juvenile and adult antisocial traits. Characteristics of the shared or family environment that promote antisocial behavior during childhood and early adolescence also promote later antisocial behavior, but to a much lesser extent. Genetic causal factors are much more prominent for adult than for juvenile antisocial traits.

  10. 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.

  11. Juveniles' Motivations for Remaining in Prostitution

    Science.gov (United States)

    Hwang, Shu-Ling; Bedford, Olwen

    2004-01-01

    Qualitative data from in-depth interviews were collected in 1990-1991, 1992, and 2000 with 49 prostituted juveniles remanded to two rehabilitation centers in Taiwan. These data are analyzed to explore Taiwanese prostituted juveniles' feelings about themselves and their work, their motivations for remaining in prostitution, and their difficulties…

  12. DERMATOMIOSITIS JUVENIL Y EMBARAZO

    OpenAIRE

    Evans M,Gregorio; Poulsen R,Ronald; Blanco R,Romiely; Luna V,Viviana

    2002-01-01

    La dermatomiositis juvenil es un desorden inflamatorio crónico multisistémico del tejido conectivo. Tiene una incidencia de 2-3/100.000/año. Con la disminución en la mortalidad experimentada en los últimos decenios, la atención está cifrada en la morbilidad a largo plazo y en las alteraciones funcionales. Con un tratamiento agresivo los niños con dermatomiositis juvenil generalmente tienen un futuro promisorio, sin incapacidad o con incapacidad mínima. La mortalidad actualmente se estima cerc...

  13. 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

  14. 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…

  15. 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.

  16. AFSC/ABL: Juvenile rockfish DNA species identification

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Many pelagic juvenile rockfish (Sebastes) were collected in juvenile salmonid surveys in the Gulf of Alaska (GOA) from 1998 to 2002. Often species identification of...

  17. 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…

  18. 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…

  19. "Scared Straight" and other juvenile awareness programs for preventing juvenile delinquency.

    Science.gov (United States)

    Petrosino, A; Turpin-Petrosino, C; Buehler, J

    2002-01-01

    'Scared Straight' and other programmes involve organised visits to prison by juvenile delinquents or children at risk for criminal behavior. programmes are designed to deter participants from future offending through first-hand observation of prison life and interaction with adult inmates. These programmes remain in use world-wide despite studies and reviews questioning their effectiveness. To assess the effects of programmes comprising organised visits to prisons by juvenile delinquents (officially adjudicated or convicted by a juvenile court) or pre-delinquents (children in trouble but not officially adjudicated as delinquents), aimed at deterring them from criminal activity. Handsearching by the first author in identifying randomised field trials 1945-1993 relevant to criminology was augmented by structured searches of 16 electronic data bases, including the Campbell SPECTR database of trials and the Cochrane CCTR. Experts in the field were consulted and relevant citations were followed up. Studies that tested the effects of any program involving the organised visits of juvenile delinquents or children at-risk for delinquency to penal institutions were included. Studies that included overlapping samples of juvenile and young adults (e.g. ages 14-20) were included. We only considered studies that randomly or quasi-randomly (i.e. alternation) assigned participants to conditions. Each study had to have a no-treatment control condition with at least one outcome measure of "post-visit" criminal behavior. We report narratively on the nine eligible trials. We conducted one meta-analysis of post-intervention offending rates using official data. Information from other sources (e.g. self-report) was either missing from some studies or critical information was omitted (e.g. standard deviations). We examined the immediate post-treatment effects (i.e. "first-effects") by computing Odds Ratios (OR) for data on proportions of each group re-offending, and assumed both fixed and

  20. 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)

  1. 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.

  2. 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.

  3. Preventing Juvenile Delinquency

    Directory of Open Access Journals (Sweden)

    Carolina dos Reis

    2016-04-01

    Full Text Available This article aims to problematize discourses about protection and care that have surrounded compulsory hospitalization by evidencing its use as a control and punishment mechanism that increases the social vulnerability of young drug users. For such, we analyze lawsuits involving juveniles who were consigned to psychiatric institutions for drug addiction treatment as a protection measure in the state of Rio Grande do Sul, in Brazil. The analysis of the materials has evidenced discourses that have circumscribed young drug users and constructed this population as potentially dangerous subjects as well as a population category at risk. In this sense, we point out how compulsory hospitalization has emerged out of the lawsuits as a tool for prevention of juvenile delinquency.

  4. 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...

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. The World of Juvenile Justice According to the Numbers

    Science.gov (United States)

    Rozalski, Michael; Deignan, Marilyn; Engel, Suzanne

    2008-01-01

    Intended to be an instructive, yet sobering, introduction to the complex and disturbing nature of the juvenile justice system, this article details the "numbers," including selected percentages, ratios, and dollar amounts, that are relevant to developing a better understanding of the juvenile justice system. General statistics about juvenile and…

  10. 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.

  11. HIV testing among non-incarcerated substance-abusing juvenile offenders.

    Science.gov (United States)

    Tolou-Shams, Marina; Conrad, Selby; Louis, Alaina; Shuford, Sarah Hart; Brown, Larry K

    2015-11-01

    Juvenile offenders are a subgroup of adolescents at particular risk for HIV/STI infection. Although HIV prevalence among these youth is low (justice system, which is known to have an extremely high rate of HIV infection. US constitutional mandates provide HIV/STI testing for incarcerated juveniles, but close to 80% of juvenile arrestees are never detained. Moreover, although they engage in similar HIV risk behaviors as those detained, they have limited access to available HIV/STI testing services. Thus, our study examined rates of lifetime HIV testing among a pilot sample of 60 court-involved, substance-using juveniles monitored in the community to explore rates of testing and the reasons related to lifetime testing among a high-risk, yet understudied US juvenile population.

  12. 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.

  13. '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.

  14. 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.

  15. A Giant Juvenile Nasopharyngeal Angiofibroma

    Science.gov (United States)

    Yüce, Salim; Uysal, İsmail Önder; Doğan, Mansur; Polat, Kerem; Şalk, İsmail; Müderris, Suphi

    2012-01-01

    Juvenile nasopharyngeal angiofibroma (JNA) are locally growing highly vascular tumours. They are treated primarily by surgical excision ranging from open approach to endoscopic approach. We presented a 20-year-old male with a giant nasopharyngeal juvenile angiofibroma obliterating the pterygopalatine fossa bilaterally, invasing the sphenoid bone and extending to the left nasal passage. His complaints were epistaxis and nasal obstruction. After embolization, the patient was treated surgically with endoscopic approach and discharged as cured without any complication. PMID:23714961

  16. Combination of Juvenile Papillomatosis, Juvenile Fibroadenoma and Intraductal Carcinoma of the Breast in a 15-Year-old Girl.

    Science.gov (United States)

    Sedloev, Theophil; Bassarova, Assia; Angelov, Kostadin; Vasileva, Mariela; Asenov, Yavor

    2015-09-01

    The association of juvenile papillomatosis with carcinoma is proven, but very rare, as there exist several reported cases. A 15-year-old girl with no family history of breast cancer presented with two masses in the left breast. The excisional biopsy on both lumps revealed juvenile fibroadenoma and juvenile papillomatosis epithelial proliferation multiple cystic expanded channels. In some of these channels, cytological features of intraductal carcinoma were observed. We performed a full immunohistochemical examination of the juvenile papillomatosis. The patient refused any further surgical or adjuvant treatment. There are no signs of recurrence in the 15 year follow-up. This case is a diagnostic and therapeutic challenge, taking into account the patient's age and the controversial treatment recommendations. Good collaboration between surgeons and pathologists is essential for an accurate diagnostic process and aims to avoid under- or overtreatment. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  17. 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.

  18. Challenges and prospects of the juvenile justice administration in ...

    African Journals Online (AJOL)

    Juvenile justice administration in Nigeria is weak and has been given very little priority, despite Nigeria being signatory to the major international instruments relevant to the administration of juvenile justice. This is attributable to the history of the penal system of Nigeria, with laws guiding juvenile justice administration having ...

  19. 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

  20. 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,...

  1. 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…

  2. 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.

  3. 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.

  4. 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.

  5. 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...

  6. A new mass mortality of juvenile Protoceratops and size-segregated aggregation behaviour in juvenile non-avian dinosaurs.

    Directory of Open Access Journals (Sweden)

    David W E Hone

    Full Text Available BACKGROUND: Monodominant bonebeds are a relatively common occurrence for non-avian dinosaurs, and have been used to infer associative, and potentially genuinely social, behavior. Previously known assemblages are characterized as either mixed size-classes (juvenile and adult-sized specimens together or single size-classes of individuals (only juveniles or only adult-sized individuals within the assemblage. In the latter case, it is generally unknown if these kinds of size-segregated aggregations characterize only a particular size stage or represent aggregations that happened at all size stages. Ceratopsians ("horned dinosaurs" are known from both types of assemblages. METHODS/PRINCIPAL FINDINGS: Here we describe a new specimen of the ceratopsian dinosaur Protoceratops andrewsi, Granger and Gregory 1923 from Mongolia representing an aggregation of four mid-sized juvenile animals. In conjunction with existing specimens of groups of P. andrewsi that includes size-clustered aggregations of young juveniles and adult-sized specimens, this new material provides evidence for some degree of size-clustered aggregation behaviour in Protoceratops throughout ontogeny. This continuity of size-segregated (and presumably age-clustered aggregation is previously undocumented in non-avian dinosaurs. CONCLUSIONS: The juvenile group fills a key gap in the available information on aggregations in younger ceratopsians. Although we support the general hypothesis that many non-avian dinosaurs were gregarious and even social animals, we caution that evidence for sociality has been overstated and advocate a more conservative interpretation of some data of 'sociality' in dinosaurs.

  7. A new mass mortality of juvenile Protoceratops and size-segregated aggregation behaviour in juvenile non-avian dinosaurs.

    Science.gov (United States)

    Hone, David W E; Farke, Andrew A; Watabe, Mahito; Shigeru, Suzuki; Tsogtbaatar, Khishigjav

    2014-01-01

    Monodominant bonebeds are a relatively common occurrence for non-avian dinosaurs, and have been used to infer associative, and potentially genuinely social, behavior. Previously known assemblages are characterized as either mixed size-classes (juvenile and adult-sized specimens together) or single size-classes of individuals (only juveniles or only adult-sized individuals within the assemblage). In the latter case, it is generally unknown if these kinds of size-segregated aggregations characterize only a particular size stage or represent aggregations that happened at all size stages. Ceratopsians ("horned dinosaurs") are known from both types of assemblages. Here we describe a new specimen of the ceratopsian dinosaur Protoceratops andrewsi, Granger and Gregory 1923 from Mongolia representing an aggregation of four mid-sized juvenile animals. In conjunction with existing specimens of groups of P. andrewsi that includes size-clustered aggregations of young juveniles and adult-sized specimens, this new material provides evidence for some degree of size-clustered aggregation behaviour in Protoceratops throughout ontogeny. This continuity of size-segregated (and presumably age-clustered) aggregation is previously undocumented in non-avian dinosaurs. The juvenile group fills a key gap in the available information on aggregations in younger ceratopsians. Although we support the general hypothesis that many non-avian dinosaurs were gregarious and even social animals, we caution that evidence for sociality has been overstated and advocate a more conservative interpretation of some data of 'sociality' in dinosaurs.

  8. 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.

  9. 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…

  10. Sports Participation and Juvenile Delinquency: A Meta-Analytic Review.

    Science.gov (United States)

    Spruit, Anouk; van Vugt, Eveline; van der Put, Claudia; van der Stouwe, Trudy; Stams, Geert-Jan

    2016-04-01

    Participation in sports activities is very popular among adolescents, and is frequently encouraged among youth. Many psychosocial health benefits in youth are attributed to sports participation, but to what extent this positive influence holds for juvenile delinquency is still not clear on both the theoretical and empirical level. There is much controversy on whether sports participation should be perceived as a protective or a risk factor for the development of juvenile delinquency. A multilevel meta-analysis of 51 published and unpublished studies, with 48 independent samples containing 431 effect sizes and N = 132,366 adolescents, was conducted to examine the relationship between sports participation and juvenile delinquency and possible moderating factors of this association. The results showed that there is no overall significant association between sports participation and juvenile delinquency, indicating that adolescent athletes are neither more nor less delinquent than non-athletes. Some study, sample and sports characteristics significantly moderated the relationship between sports participation and juvenile delinquency. However, this moderating influence was modest. Implications for theory and practice concerning the use of sports to prevent juvenile delinquency are discussed.

  11. Moral development of solo juvenile sex offenders

    NARCIS (Netherlands)

    van Vugt, E.; Stams, G.J.; Dekovic, M.; Brugman, D.; Rutten, E.; Hendriks, J.

    2008-01-01

    This study compared the moral development of solo juvenile male sex offenders (n = 20) and juvenile male non-offenders (n = 76), aged 13-19 years, from lower socioeconomic and educational backgrounds. The Moral Orientation Measure (MOM) was used to assess punishment- and victim-based moral

  12. [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.

  13. 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

  14. 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

  15. 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.

  16. Juvenil idiopatisk arthritis

    DEFF Research Database (Denmark)

    Herlin, Troels

    2002-01-01

    The new classification of juvenile idiopathic arthritis (JIA) is described in this review. Clinical characteristics divide JIA in to subtypes: systemic, oligoarticular (persistent and extended type), RF-positive and--negative polyarticular, enthesitis-related arthritis and psoriatic arthritis...

  17. Orofacial pain, jaw function, and temporomandibular disorders in adult women with a history of juvenile chronic arthritis or persistent juvenile chronic arthritis

    DEFF Research Database (Denmark)

    Bakke, M.; Zak, M.; Jensen, B.L.

    2001-01-01

    Orofacial pain, jaw function, temporomandibular disorders, adult women persistent juvenil chronic arthritis......Orofacial pain, jaw function, temporomandibular disorders, adult women persistent juvenil chronic arthritis...

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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%).

  3. 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.

  4. 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.

  5. 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…

  6. Juvenile Obesity, Physical Activity, and Lifestyle Changes.

    Science.gov (United States)

    Bar-Or, Oded

    2000-01-01

    Because many obese children become obese adults, the recent rapid increase in juvenile obesity poses a major public health challenge. Enhanced physical activity is a cornerstone in a multidisciplinary approach to preventing and treating juvenile obesity. Giving exercise recommendations focused for obese youth is critical. Cutting down on sedentary…

  7. Preliminary evidence of altered biomechanics in adolescents with juvenile fibromyalgia.

    Science.gov (United States)

    Sil, Soumitri; Thomas, Staci; DiCesare, Christopher; Strotman, Daniel; Ting, Tracy V; Myer, Gregory; Kashikar-Zuck, Susmita

    2015-01-01

    Juvenile fibromyalgia (FM) is characterized by chronic musculoskeletal pain and marked reduction in physical activity. Despite recommendations for exercise to manage juvenile FM pain, exercise adherence is poor. Because of pain and activity avoidance, adolescents with juvenile FM are at risk for altered joint mechanics that may make them susceptible to increased pain and reduced tolerance for exercise. The primary aim of this study was to assess functional deficits in patients with juvenile FM compared to healthy controls using objective biomechanical assessment. Female adolescent patients with juvenile FM (n = 17) and healthy controls (n = 14) completed biomechanical assessments, including gait analysis and tests of lower extremity strength (isokinetic knee extension/flexion and hip abduction) and functional performance (drop vertical jump test) along with self-reported measures of disability (Functional Disability Inventory), pain intensity, depressive symptoms (Children's Depression Inventory), and fear of movement (Tampa Scale of Kinesiophobia). Patients with juvenile FM demonstrated mild deficiencies in walking gait and functional performance (P < 0.05 for both) and significantly lower left knee extension and flexion strength (18-22% deficit) and bilateral hip abduction strength (34-38%) compared with healthy controls (P < 0.008 for all). Patients with juvenile FM reported significantly higher functional disability, pain intensity, depressive symptoms, and fear of movement relative to controls (P < 0.01 for all). This study showed that adolescents with juvenile FM exhibited objective alterations in biomechanics and self-reported fear of movement that may have reinforced their activity avoidance. Interventions for juvenile FM should include a focus on correcting functional deficits and instilling greater confidence in adolescents with juvenile FM to engage in exercise to improve functional outcomes. Copyright © 2015 by the American College of Rheumatology.

  8. 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.

  9. Examination of the influence of juvenile Atlantic salmon on the feeding mode of juvenile steelhead in Lake Ontario tributaries

    Science.gov (United States)

    Johnson, James H.; Waldt, Emily M.

    2014-01-01

    We examined diets of 1204 allopatric and sympatric juvenile Atlantic salmon (Salmo salar) and steelhead (Oncorhynchus mykiss) in three tributaries of Lake Ontario. The diet composition of both species consisted primarily of ephemeropterans, trichopterans, and chironomids, although juvenile steelhead consumed more terrestrial invertebrates, especially at the sympatric sites. Subyearlings of both species consumed small prey (i.e. chironomids) whereas large prey (i.e. perlids) made up a higher percentage of the diet of yearlings. The diet of juvenile steelhead at the allopatric sites was more closely associated with the composition of the benthos than with the drift, but was about equally associated with the benthos and drift at the sympatric sites. The diet of both subyearling and yearling Atlantic salmon was more closely associated with the benthos than the drift at the sympatric sites. The evidence suggests that juvenile steelhead may subtly alter their feeding behavior in sympatry with Atlantic salmon. This behavioral adaptation may reduce competitive interactions between these species.

  10. 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.

  11. 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...

  12. 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.

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

    Science.gov (United States)

    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.

  14. Intelligence Score Profiles of Female Juvenile Offenders

    Science.gov (United States)

    Werner, Shelby Spare; Hart, Kathleen J.; Ficke, Susan L.

    2016-01-01

    Previous studies have found that male juvenile offenders typically obtain low scores on measures of intelligence, often with a pattern of higher scores on measures of nonverbal relative to verbal tasks. The research on the intelligence performance of female juvenile offenders is limited. This study explored the Wechsler Intelligence Scale for…

  15. Penalty responsibility of juveniles in the Republic of Srpska

    Directory of Open Access Journals (Sweden)

    Grbić-Pavlović Nikolina

    2011-01-01

    Full Text Available The youngest members of organized society, more intensive than ever enter the circle of those whose behavior is deviant. Juvenile delinquency is a social problem, which recently experienced an expansion in all modern countries, including Bosnia and Herzegovina and the Republic of Srpska. Considering the fact that juvenile delinquency includes lighter criminal conducts, such as, for example misdemeanors, in this paper a position of juveniles when they are a perpetrators of misdemeanors will be analyzed. Also, the paper will statistically show the number of misdemeanors in the field of public peace and order that juveniles conducted in the Republic of Srpska in the period 2004-2009.

  16. Delincuencia y responsabilidad penal juvenil en Colombia

    Directory of Open Access Journals (Sweden)

    Cristina Montalvo Velásquez

    2011-01-01

    Full Text Available ResumenEl término «delincuencia juvenil» fue acuñado en Inglaterra en el año 1815, “Se entiende por delincuencia juvenil el conjunto de delitos, contravenciones o comportamientos socialmente reprochables, que cometen las personas consideradas como jóvenes por la ley”1 . Cada Estado está sujeto a su propio sistema jurídico, para algunos es delincuente juvenil el adolescente que comete acciones sancionadas por la ley sin importar su gravedad, otros Estados sólo consideran como delincuente juvenil al joven que comete un acto delictivo grave.El fenómeno de la delincuencia juvenil es algo que se inscribe en los espacios de una sociedad en la cual su estructura material, y su formación social consecuente, se halla en una profunda crisis. Que jóvenes conformen bandas de delincuencia organizada nos está indicando que son el resultado de la misma criminalidad general que se ha apoderado de la sociedad en la perspectiva de lograr sobrevivir materialmente. El capitalismo no es sólo acumulación de riqueza sino concentración de la misma en muy pocas manos; y todo el sistema institucional y legal tiende a favorecer ese fenómeno porque éste constituye la supra estructura del modo de producción capitalista. Así como los adultos se organizan para delinquir, lo hacen los niños y los jóvenes a partir de una edad en la cual pueden percibir que la sociedad no es sana y no tienen porvenir humano en ella. Abandonados y sujetos a la violencia que engendra el sistema, ellos simplemente responden en una manifestación de reflejos condicionados que sostienen la sobrevivencia en forma instintiva; “los niños no saben de normas legales sino de formas de sobrevivir a semejante situación; el instinto de sobrevivencia no tiene edades ni la normatividad puede incidir en él”.Palabras ClavesDelincuencia juvenil, Jóvenes, Criminalidad, Familia, Factores, Acto delictivo, Responsabilidad Penal.AbstractThe term “juvenile delinquency” was coined in

  17. 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.

  18. 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

  19. Evolution of Juvenile Ankylosing Spondylitis

    Directory of Open Access Journals (Sweden)

    Ye.V. Prohorov

    2013-02-01

    Full Text Available Evolution of juvenile ankylosing spondylitis tend to follow a more frequent involvement in the pathological process of elbow and ankle joints, development of enthesiopathies, changes of intraarticular meniscal horns, forming of Baker’s cysts, cartilage flaps and systemic osteoporosis, and total value of all these signs 13 times exceeds thereof in patients with with the debut of disease in adulthood, but for juvenile ankylosing spondylitis vertebral lesion is less common. Age dimorphism of the use of certain groups of drugs and physiotherapy facilities is observed.

  20. Yolo Bypass Juvenile Salmon Utilization Study 2016—Summary of acoustically tagged juvenile salmon and study fish release, Sacramento River, California

    Science.gov (United States)

    Liedtke, Theresa L.; Hurst, William R.

    2017-09-12

    The Yolo Bypass is a flood control bypass in Sacramento Valley, California. Flood plain habitats may be used for juvenile salmon rearing, however, the potential value of such habitats can be difficult to evaluate because of the intermittent nature of inundation events. The Yolo Bypass Juvenile Salmon Utilization Study (YBUS) used acoustic telemetry to evaluate the movements and survival of juvenile salmon adjacent to and within the Yolo Bypass during the winter of 2016. This report presents numbers, size data, and release data (times, dates, and locations) for the 1,197 acoustically tagged juvenile salmon released for the YBUS from February 21 to March 18, 2016. Detailed descriptions of the surgical implantation of transmitters are also presented. These data are presented to support the collaborative, interagency analysis and reporting of the study findings.

  1. 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.

  2. 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

  3. Prevalence of traumatic brain injury in juvenile offenders: a meta-analysis.

    Science.gov (United States)

    Farrer, Thomas J; Frost, R Brock; Hedges, Dawson W

    2013-01-01

    Studies of traumatic brain injury (TBI) among adult populations demonstrate that such injuries can lead to aggressive behaviors. Related findings suggest that incarcerated individuals have high rates of brain injuries. Such studies suggest that traumatic brain injury may be related to the etiology and recidivism of criminal behavior. Relatively few studies have examined the prevalence of TBI using a delinquent juvenile sample. In order to assess the relationship between TBI and juvenile offender status, the current study used meta-analytic techniques to examine the odds of having a TBI among juvenile offenders. Across 9 studies, we found that approximately 30% of juvenile offenders have sustained a previous brain injury. Across 5 studies that used a control group, a calculated summary odds ratio of 3.37 suggests that juvenile offenders are significantly more likely to have a TBI compared to controls. Results suggest that the rate of TBIs within the juvenile offender population is significant and that there may be a relationship between TBIs and juvenile criminal behavior.

  4. 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…

  5. 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…

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

    Science.gov (United States)

    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…

  7. 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…

  8. 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.

  9. 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...

  10. Miastenia gravis juvenil Juvenile myasthenia gravis

    OpenAIRE

    Oscar Papazian; Israel Alfonso; Nayle Araguez

    2009-01-01

    La miastenia gravis juvenil (MGJ) es un trastorno crónico auto inmune en el cual existen anticuerpos séricos que al unirse a los receptores de acetilcolin nicotínicos de la membrana muscular de la placa motora alteran la transmisión neuromuscular. El resultado es fatiga muscular precoz con progresión a la parálisis durante estados de contracción muscular iterativos (movimientos) o sostenidos (posturas) y más raramente parálisis permanente durante el reposo. Los músculos inervados por los nerv...

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

    Science.gov (United States)

    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.

  12. Juvenile xanthogranuloma of the corneoscleral limbus.

    Science.gov (United States)

    Yanoff, M; Perry, H D

    1995-07-01

    Juvenile xanthogranuloma is a rare and usually benign skin disease of unknown cause that occurs in infants and young children. We studied a case of juvenile xanthogranuloma of the corneoscleral limbus in a 17-year-old black boy, who presented with a 5-month history of a lump in the right eye. The lesion extended from the superior limbus, fanning out as it proceeded posteriorly for 6 mm with a width of 9 mm and a height of 2 to 3 mm. This yellow-orange mass was vascular and firmly fixed to the underlying tissue. The lesion was diagnosed as a dermoid and observed for 7 months without documented growth before an uneventful excisional biopsy was performed. The pathologic diagnosis showed the characteristic picture of juvenile xanthogranuloma with numerous Touton giant cells. Lipid stains provided further confirmation.

  13. Modelling population effects of juvenile offshore fish displacement towards adult habitat

    DEFF Research Database (Denmark)

    van de Wolfshaar, K.E.; Tulp, I.; Wennhage, H.

    2015-01-01

    consequences on population dynamics through changes in resource use and competition. To explore this, a conceptual stage-structured model was developed with 3 stages and 2 resources and allowing a move of large juveniles from the shallow to the deep habitat. Large juveniles compete with small juveniles...... in shallow waters and with adults in deeper waters. Alternative stable states occur, with one state dominated by small juvenile biomass and the other dominated by adult biomass. The model results show for both states that while large juvenile biomass responds to a change in time spent in the deep habitat...

  14. Imaging of juvenile spondyloarthritis. Part I: Classifications and radiographs

    Directory of Open Access Journals (Sweden)

    Iwona Sudoł-Szopińska

    2017-09-01

    Full Text Available Juvenile spondyloarthropathies are manifested mainly by symptoms of peripheral arthritis and enthesitis. By contrast with adults, children rarely present with sacroiliitis and spondylitis. Imaging and laboratory tests allow early diagnosis and treatment. Conventional radiographs visualize late inflammatory lesions and post-inflammatory complications. Early diagnosis is possible with the use of ultrasonography and magnetic resonance imaging. The first part of the article presents classifications of juvenile spondyloarthropathies and discusses their radiographic presentation. Typical radiographic features of individual types of juvenile spondyloarthritis are listed (including ankylosing spondylitis, juvenile psoriatic arthritis, reactive arthritis and arthritis in the course of inflammatory bowel diseases. The second part will describe changes visible on ultrasonography and magnetic resonance imaging. In patients with juvenile spondyloarthropathies, these examinations are conducted to diagnose inflammatory lesions in peripheral joints, tendon sheaths, tendons and bursae. Moreover, magnetic resonance imaging also visualizes early inflammatory changes in the axial skeleton and subchondral bone marrow edema, which is considered an early sign of inflammation.

  15. Spatial dynamics of juvenile anchovy in the Bay of Biscay

    KAUST Repository

    Boyra, Guillermo

    2016-07-08

    In autumn 2009, the implementation of two successive acoustic surveys targeting juvenile anchovy (Engraulis encrasicolus) in the Bay of Biscay allowed us to monitor the changes in the spatial distribution and aggregation patterns of juveniles of this species during 45 days under fairly stable meteorological conditions. Juvenile anchovy changed its biological condition and behavior in a different manner in two distinct areas. In the Spanish sector, the juveniles migrated 20 nautical miles (n.mi.) towards the coast, but they remained on the shelf and near the surface during the whole surveyed period. As the advance towards the shelf break progressed, their area of distribution decreased, their density increased and the juveniles spread in fewer but heavier shoals. In the French sector, the juveniles also migrated from slope waters towards the coast at a similar velocity, but they crossed the shelf break into the continental shelf, where they increased their mean depth significantly until gradually adopting the typical nyctemeral migrations of adult anchovy. The mean length of the juveniles that adopted the nyctemeral migrations was significantly higher than that of the juveniles remaining at the surface, suggesting that body size is relevant to accomplish this change. Besides, the stronger temperature gradients between the shelf and oceanic waters in the Spanish sector, favored by a narrow shelf, may have acted as a barrier influencing the distinct observed spatial patterns in the two areas. © 2016 John Wiley & Sons Ltd

  16. Spatial dynamics of juvenile anchovy in the Bay of Biscay

    KAUST Repository

    Boyra, Guillermo; Peñ a, Marian; Cotano, Unai; Irigoien, Xabier; Rubio, Anna; Nogueira, Enrique

    2016-01-01

    In autumn 2009, the implementation of two successive acoustic surveys targeting juvenile anchovy (Engraulis encrasicolus) in the Bay of Biscay allowed us to monitor the changes in the spatial distribution and aggregation patterns of juveniles of this species during 45 days under fairly stable meteorological conditions. Juvenile anchovy changed its biological condition and behavior in a different manner in two distinct areas. In the Spanish sector, the juveniles migrated 20 nautical miles (n.mi.) towards the coast, but they remained on the shelf and near the surface during the whole surveyed period. As the advance towards the shelf break progressed, their area of distribution decreased, their density increased and the juveniles spread in fewer but heavier shoals. In the French sector, the juveniles also migrated from slope waters towards the coast at a similar velocity, but they crossed the shelf break into the continental shelf, where they increased their mean depth significantly until gradually adopting the typical nyctemeral migrations of adult anchovy. The mean length of the juveniles that adopted the nyctemeral migrations was significantly higher than that of the juveniles remaining at the surface, suggesting that body size is relevant to accomplish this change. Besides, the stronger temperature gradients between the shelf and oceanic waters in the Spanish sector, favored by a narrow shelf, may have acted as a barrier influencing the distinct observed spatial patterns in the two areas. © 2016 John Wiley & Sons Ltd

  17. Using the Juvenile Justice Poster. Teaching Strategy.

    Science.gov (United States)

    Update on Law-Related Education, 2000

    2000-01-01

    Presents a lesson that can help students review and summarize what they have learned about the juvenile justice system. Explains that the students discuss how the juvenile justice system can be improved and conduct a survey on how it might be changed in the future. Provides a copy of the survey and directions. (CMK)

  18. Reformations in Zimbabwe's juvenile justice system | Ruparanganda ...

    African Journals Online (AJOL)

    Children in conflict with the law are often stigmatized and shunned by society as they are perceived as a threat to society. Historically, Zimbabwe's juvenile justice system has been retributive and focused on punishing the juvenile offender. As a result, it has been criticised from a number of viewpoints, including the need to ...

  19. Juvenile Delinquency and Teenage Pregnancy: A Comparison of Ecological Risk Profiles among Midwestern White and Black Female Juvenile Offenders

    Science.gov (United States)

    Khurana, Atika; Cooksey, Elizabeth C.; Gavazzi, Stephen M.

    2011-01-01

    The authors examined ecological risk factors associated with teen pregnancy with a sample of 1,190 court-involved female juvenile offenders between 11 and 18 years of age. Data were obtained from five Midwestern juvenile county courts using a recently developed youth risk assessment instrument called the global risk assessment device (GRAD). In…

  20. 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)

  1. 83 CHALLENGES AND PROSPECTS OF THE JUVENILE JUSTICE ...

    African Journals Online (AJOL)

    Fr. Ikenga

    Juvenile justice administration in Nigeria is weak and has been given very .... The Nigerian criminal justice system, of which the juvenile justice system is an integral part, ... as instruments of security and justice but as weapons of oppression8.

  2. [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.

  3. Bilateral, independent juvenile nasopharyngeal angiofibroma: case report.

    Science.gov (United States)

    Mørkenborg, M-L; Frendø, M; Stavngaard, T; Von Buchwald, C

    2015-10-01

    Juvenile nasopharyngeal angiofibroma is a benign, vascular tumour that primarily occurs in adolescent males. Despite its benign nature, aggressive growth patterns can cause potential life-threatening complications. Juvenile nasopharyngeal angiofibroma is normally unilateral, originating from the sphenopalatine artery, but bilateral symptoms can occur if a large tumour extends to the contralateral side of the nasopharynx. This paper presents the first reported case of true bilateral extensive juvenile nasopharyngeal angiofibroma involving clinically challenging pre-surgical planning and surgical strategy. A 21-year-old male presented with increasing bilateral nasal obstruction and discharge. Examination revealed tumours bilaterally and imaging demonstrated non-contiguous tumours. Pre-operative angiography showed strictly ipsilateral vascular supplies requiring bilateral embolisation. Radical removal performed as one-step, computer-assisted functional endoscopic sinus surgery was performed. The follow-up period was uncomplicated. This case illustrates the importance of suspecting bilateral juvenile nasopharyngeal angiofibroma in patients presenting with bilateral symptoms. Our management, including successful pre-operative planning, enabled one-step total removal of both tumours and rapid patient recovery.

  4. Radium rentention and dosimetry in juvenile beagles

    International Nuclear Information System (INIS)

    Lloyd, R.D.; Jones, C.W.; Bruenger, F.W.; Atherton, D.R.; Mays, C.W.

    1983-01-01

    Retention of administered 226 Ra was substantially greater in beagles injected as 3-month-old juveniles than as 1.4-year-old adults, but the measured 222 Rn/ 226 Ra ratio in bone was significantly less in juveniles for about the first 600 days after injection. An equation that describes the total-body biological retention R in beagles injected with 226 Ra at 3 months of age at any time t (in days) after injection during the first 6.6 years is R = 0.331e/sup -0.206t/ + 0.245e/sup -0.00374t/ + 0.424e/sup -0.000114t/. The rate constant of the final term in the equation for juveniles is similar to that for young adults, suggesting that this component reflects the net turnover rate in the slowly remodeling component of adult bone. Compared to young adult beagles, animals injected as juveniles had a greater fraction of their retained 226 Ra in parts of the skeleton containing much cortical bone, such as paws, and a smaller fraction in those parts containing much trabecular bone

  5. 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…

  6. Race and the fragility of the legal distinction between juveniles and adults.

    Directory of Open Access Journals (Sweden)

    Aneeta Rattan

    Full Text Available Legal precedent establishes juvenile offenders as inherently less culpable than adult offenders and thus protects juveniles from the most severe of punishments. But how fragile might these protections be? In the present study, simply bringing to mind a Black (vs. White juvenile offender led participants to view juveniles in general as significantly more similar to adults in their inherent culpability and to express more support for severe sentencing. Indeed, these differences in participants' perceptions of this foundational legal precedent distinguishing between juveniles and adults accounted for their greater support for severe punishment. These results highlight the fragility of protections for juveniles when race is in play. Furthermore, we suggest that this fragility may have broad implications for how juveniles are seen and treated in the criminal justice system.

  7. 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.

  8. 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.

  9. 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.

  10. Criminal history and future offending of juveniles convicted of the possession of child pornography.

    Science.gov (United States)

    Aebi, Marcel; Plattner, Belinda; Ernest, Melanie; Kaszynski, Katie; Bessler, Cornelia

    2014-08-01

    Most child pornography is distributed online. It is estimated that 3% to 15% of child pornography consumers are juveniles. The present study analyzed a consecutive sample of 54 male juveniles convicted of the possession of child pornography. Demographic characteristics, criminal history, and subsequent offending were assessed from criminal files and official reports. Juvenile possessors of child pornography were compared to three different groups of juveniles: Juvenile possessors of other illegal pornography (n = 42), juveniles who committed a sexual contact offense against a child (n = 64), and juveniles who committed a sexual contact offense against a peer or adult (n = 104). Juvenile possessors of child pornography were found to have downloaded the illegal material more frequently and over a longer time period than juvenile possessors of other illegal pornography. Furthermore, juvenile possessors of child pornography differed from juveniles who had committed a sexual contact offense in terms of demographics and showed fewer previous and subsequent offending than juveniles who sexually offended against a peer or adult. We conclude that juvenile possessors of child pornography need a specific target intervention focusing on dysfunctional Internet use and sexually deviant arousal. © The Author(s) 2013.

  11. Employers mexican migrants in the United States

    Directory of Open Access Journals (Sweden)

    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.

  12. Comparative analysis of diet composition and its relation to morphological characteristics in juvenile fish of three lutjanid species in a Mexican Pacific coastal lagoon

    Directory of Open Access Journals (Sweden)

    Consuelo M. Aguilar-Betancourt

    2017-12-01

    Full Text Available ABSTRACT The main goal of this research was to investigate the differences in diet composition among three species of the genus Lutjanus inhabiting a coastal lagoon as juveniles. The working hypothesis was that these species feed on a common base of food resources and therefore, some niche overlap is present in terms of general diet composition. However, changes in the trophic niche with size and differences in some morphological traits among species explain observed differences in diet. Fish were collected during 42 sampling trips conducted regularly from February 2011 to January 2012 using several types of fishing gear. Total number of analyzed stomachs was 288 for Lutjanus argentiventris from 2.3 to 19.9 cm total length (TL; 178 for Lutjanus colorado ranging from 2.4 to 30.1 cm TL; and 183 for Lutjanus novemfasciatus with 1.2 to 20.0 cm TL. Results indicate that juveniles of all three lutjanid species share a general diet based on decapods and fishes. However, L. novemfasciatus has a more piscivorous habit, which can be explained by a more slender body shape and larger teeth, characteristics, which increase fish catching performance. Larger fish of all three species eat larger prey, which is consistent with the optimum foraging theory.

  13. 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)

  14. 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)

  15. 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.

  16. Training in the Mexican company: a study of job training

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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

  18. Growth of juvenile shrimp Metapenaeus monoceros fed with squid and mussel

    Digital Repository Service at National Institute of Oceanography (India)

    Achuthankutty, C.T.; Nair, S.R.S.; Krishnakumari, L.

    Small juveniles of both sexes and females of large juveniles of Metapenaeus monoceros attained faster growth with squid diet. Males of large juveniles registered better growth with mussel diet. No significant difference was observed in moult weights...

  19. 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...

  20. 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…

  1. Social and cultural influences among Mexican border entrepreneurs.

    Science.gov (United States)

    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.

  2. Juvenile technologies in foreign publications

    Directory of Open Access Journals (Sweden)

    Shpagina E.M.

    2012-09-01

    Full Text Available The article provides the review of foreign publications, concerning the juvenile technologies used in France, Canada, Germany and Switzerland. The paper presents legal, social and psychotherapeutic aspects of juvenile judiciary in foreign countries. The authors paid special attention to the complexity of approaches to young children and teenagers who found themselves in complicated life circumstances or got into trouble with the law. The article gives examples of using the following techniques: cognitive-behavioral intervention, mediation, family therapy (including family background and family history, relations theory, narrative practices, utilization of «emotional intelligence» resources.

  3. Proverbs in Mexican American Tradition.

    Science.gov (United States)

    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)

  4. 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

  5. Corporal and capital punishment of juveniles.

    Science.gov (United States)

    Frazier, H C

    1990-01-01

    There is a previously unobserved connection between corporal punishment of public school children and capital punishment of juveniles. Both are barometers of acceptable levels of violent punishment and their elimination is a hallmark of a maturing and decent society. Within a majority of the eighteen states where school authorities most frequently strike children are housed 25 of the nation's 28 juvenile death row inmates. On average, the homicide rates of these jurisdictions are two and a half times greater than those that have abolished both state-sanctioned corporal and capital punishment or limit death sentences to those age eighteen and older at the time of their crime(s). Most of the eighteen state abolitions of corporal punishment occurred in the 1980's. The US Supreme Court has ruled both corporal and capital punishment of juveniles constitutional. Additional state legislative abolition of both is anticipated in the 1990s.

  6. 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

  7. 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. .

  8. 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...

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

    Science.gov (United States)

    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.

  10. 28 CFR 0.94 - Office of Juvenile Justice and Delinquency Prevention.

    Science.gov (United States)

    2010-07-01

    ... Delinquency Prevention. 0.94 Section 0.94 Judicial Administration DEPARTMENT OF JUSTICE ORGANIZATION OF THE... Delinquency Prevention. The Office of Juvenile Justice and Delinquency Prevention is headed by an...., relating to juvenile delinquency, the improvement of juvenile justice systems and missing children. ...

  11. [Species and size composition of fishes in Barra de Navidad lagoon, Mexican central Pacific].

    Science.gov (United States)

    González-Sansón, Gaspar; Aguilar-Betancourt, Consuelo; Kosonoy-Aceves, Daniel; Lucano-Ramírez, Gabriela; Ruiz-Ramírez, Salvador; Flores-Ortega, Juan Ramón; Hinojosa-Larios, Angel; de Asís Silva-Bátiz, Francisco

    2014-03-01

    Coastal lagoons are considered important nursery areas for many coastal fishes. Barra de Navidad coastal lagoon (3.76km2) is important for local economy as it supports tourism development and artisanal fisheries. However, the role of this lagoon in the dynamics of coastal fish populations is scarcely known. Thus, the objectives of this research were: to characterize the water of the lagoon and related weather conditions, to develop a systematic list of the ichthyofauna, and to estimate the proportion of juveniles in the total number of individuals captured of most abundant species. Water and fish samples were collected between March 2011 and February 2012. Physical and chemical variables were measured in rainy and dry seasons. Several fishing gears were used including a cast net, beach purse seine and gillnets of four different mesh sizes. Our results showed that the lagoon is most of the time euhaline (salinity 30-40ups), although it can be mixopolyhaline (salinity 18-30ups) during short periods. Chlorophyll and nutrients concentrations suggested eutrophication in the lagoon. Mean water temperature changed seasonally from 24.9 degrees C (April, high tide) to 31.4 degrees C (October, low tide). Considering ichthyofauna species, a total of 36 448 individuals of 92 species were collected, 31 of them adding up to 95% of the total of individuals caught. Dominant species were Anchoa spp. (44.6%), Diapterus peruvianus (10.5%), Eucinostomus currani (8.1%), Cetengraulis mysticetus (7.8%), Mugil curema (5.2%) and Opisthonema libertate (4.5%). The lagoon is an important juvenile habitat for 22 of the 31 most abundant species. These included several species of commercial importance such as snappers (Lutjanus argentiventris, L. colorado and L. novemfasciatus), snook (Centropomus nigrescens) and white mullet (Mugil curema). Other four species seem to use the lagoon mainly as adults. This paper is the first contribution on the composition of estuarine ichthyofauna in Jalisco

  12. Parental Low Self-Control, Family Environments, and Juvenile Delinquency.

    Science.gov (United States)

    Meldrum, Ryan C; Connolly, George M; Flexon, Jamie; Guerette, Rob T

    2016-10-01

    Research consistently finds that low self-control is significantly correlated with delinquency. Only recently, however, have researchers started to examine associations between parental low self-control, family environments, and child antisocial behavior. Adding to this emerging area of research, the current study examines associations between parental low self-control, aspects of the family environment, and officially recoded juvenile delinquency among a sample (N = 101) of juveniles processed through a juvenile justice assessment facility located in the Southeastern United States. Furthermore, it considers whether aspects of family environments, particularly family cohesion, family conflict, and parental efficacy, mediate the influence of parental low self-control on delinquency. The results of a series of analyses indicate that parental low self-control is correlated with various aspects of family environments and juvenile delinquency, and that the association between parental low self-control and juvenile delinquency is mediated by family environments. Supplementary analyses also suggest that the association between parental low self-control and the family environment may be reciprocal. © The Author(s) 2015.

  13. Temperament of juvenile delinquents with history of substance abuse.

    Science.gov (United States)

    Chang, Hsueh-Ling; Chen, Sue-Huei; Huang, Chien

    2007-01-01

    The etiological factors and interrelations of juvenile delinquents, with psychiatric morbidity and substance abuse have been continuously debated. Cloninger's Tridimensional Theory of Temperament has been reported to predict patterns of substance abuse and comorbidity. In the current study, we aimed to examine the usability of the theory in predicting juvenile delinquency and substance abuse. Sixty consecutive and newly incarcerated male delinquents with history of substance abuse were recruited from a juvenile correctional facility in northwestern Taiwan from January 2002 through December 2003. All subjects were assessed of their temperament, behavioral problems, and psychiatric disorders on an individual base. The juvenile delinquent subjects with childhood history of attention deficit and hyperactivity disorder (ADHD) were significantly younger, consumed less betel nuts, and had more siblings with history of drug abuse. Consistent with the results of Cloninger's studies, novelty seeking positively correlated to the amount of substance abuse, while harm avoidance inversely correlated in juvenile delinquents. Endemic trend of choice of substance abuse needs to be taken into consideration in future research projects.

  14. Machismo sustains health and illness beliefs of Mexican American men.

    Science.gov (United States)

    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.

  15. Prevention and Firesetting: Juvenile Justice and Intervention Strategies.

    Science.gov (United States)

    Slavkin, Michael L.

    2003-01-01

    Examines the literature on preventing firesetting behavior in preadolescents and adolescents, suggesting the need for policies and programs designed to help juveniles by providing community support and stability. Alternatives to juvenile justice interventions include making changes in the home environment, acquiring a greater sense of self, and…

  16. Dental and facial characteristics of patients with juvenile idiopathic arthritis Características dentárias e faciais de pacientes com artrite idiopática juvenil

    Directory of Open Access Journals (Sweden)

    Cynthia Savioli

    2004-01-01

    Full Text Available OBJECTIVE: It has been shown that the temporomandibular joint is frequently affected by juvenile idiopathic arthritis, and this degenerative disease, which may occur during facial growth, results in severe mandibular dysfunction. However, there are no studies that correlate oral health (tooth decay and gingival diseases and temporomandibular joint dysfunction in patients with juvenile idiopathic arthritis. The aim of this study is to evaluate the oral and facial characteristics of the patients with juvenile idiopathic arthritis treated in a large teaching hospital. METHOD: Thirty-six patients with juvenile idiopathic arthritis (26 female and 10 male underwent a systematic clinical evaluation of their dental, oral, and facial structures (DMFT index, plaque and gingival bleeding index, dental relationship, facial profile, and Helkimo's index. The control group was composed of 13 healthy children. RESULTS: The mean age of the patients with juvenile idiopathic arthritis was 10.8 years; convex facial profile was present in 12 juvenile idiopathic arthritis patients, and class II molar relation was present in 12 (P = .032. The indexes of plaque and gingival bleeding were significant in juvenile idiopathic arthritis patients with a higher number of superior limbs joints involved (P = .055. Anterior open bite (5 and temporomandibular joint noise (8 were present in the juvenile idiopathic arthritis group. Of the group in this sample, 94% (P = .017 had temporomandibular joint dysfunction, 80% had decreased mandibular opening (P = 0.0002, and mandibular mobility was severely impaired in 33% (P = .015. CONCLUSION: This study confirms that patients with juvenile idiopathic arthritis a have a high incidence of mandibular dysfunction that can be attributed to the direct effect of the disease in the temporomandibular joint and b have a higher incidence of gingival disease that can be considered a secondary effect of juvenile idiopathic arthritis on oral health

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

  1. Neurofibromatosis Type 1 Diagnosed in a Child Based on Multiple Juvenile Xanthogranulomas and Juvenile Myelomonocytic Leukemia

    DEFF Research Database (Denmark)

    Jans, Sune R R; Schomerus, Eckhard; Bygum, Anette

    2015-01-01

    An association between juvenile xanthogranuloma (JXG), neurofibromatosis type 1 (NF1), and juvenile myelomonocytic leukemia (JMML) has been described in the literature but has only been documented in approximately 20 cases. We diagnosed a patient with NF1 at 25 months of age, before any cutaneous...... with chemotherapy and allogenic bone marrow transplantation. With increased awareness, patients with JXG and NF1 who develop symptoms possibly related to JMML, such as paleness, skin bleeding, cough, unexplained fever, and hepatosplenomegaly, should be further evaluated. We also emphasize that multiple JXG lesions...

  2. Uveíte na artrite idiopática juvenil Uveitis in juvenile idiopathic arthritis

    Directory of Open Access Journals (Sweden)

    Adriana M. Roberto

    2002-02-01

    Full Text Available Objetivo: avaliar a freqüência de uveíte anterior crônica em pacientes com artrite idiopática juvenil (AIJ e sua associação com a presença do fator antinúcleo (FAN. Casuística e métodos: foram avaliadas, retrospectivamente, 72 crianças com diagnóstico confirmado de AIJ, que tiveram avaliação oftalmológica através da biomicroscopia para exame da câmara anterior da úvea, determinação do FAN (imunofluorescência indireta e fator reumatóide (FR (prova do látex no período inicial da doença. Para os pacientes com FAN positivo, esta avaliação foi realizada a cada três meses, e, caso contrário, a cada seis meses.Resultados: dos 72 pacientes com AIJ, 40 (55,5% crianças eram do sexo masculino e 36 (50% caucasóides. A idade média de início da AIJ foi 6,4 anos (1 a 14 anos, e a idade média na época do estudo foi de 10,4 anos (1 a 19 anos. De acordo com o tipo de início da AIJ, em 32 (44,4% crianças era pauciarticular (17 meninos e 15 meninas, em 30 (41,6% era poliarticular (17 meninos e 13 meninas, e em 10 (14% era sistêmico (6 meninos e 4 meninas. A presença de uveíte anterior crônica foi detectada em cinco (6,5% crianças com idade média de 11,4 anos. Destas, quatro (80% eram do tipo de início pauciarticular (três meninas do tipo I, com FAN positivo, e um menino do tipo I, FAN negativo, e uma menina com doença poliarticular (FAN e FR negativos. Neste grupo, a idade de início da AIJ foi em média 5,1 anos (3 a 12 anos, e a idade de início da uveíte foi em média de 9 anos (4 a 16 anos. O FAN foi positivo em 3/5 pacientes (60% com uveíte. Dentre os pacientes com AIJ e sem uveíte (67 crianças, oito (12% apresentaram FAN positivo. Quanto à evolução dos pacientes com comprometimento ocular, três crianças tiveram apenas um episódio de uveíte, e duas crianças apresentaram quatro recorrências da uveíte com catarata sem atividade articular associada. A presença do FAN foi estatisticamente mais freq

  3. Juvenile Rockfish Recruitment Cruise

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In 1983, the groundfish analysis project began a series of yearly cruises designed to assess the annual abundance of juvenile rockfish along the central California...

  4. Psychotic Symptomatology in a Juvenile Court Clinic Population

    Science.gov (United States)

    Lewis, Dorothy Otnow; And Others

    1973-01-01

    This report indicating an unexpectedly high incidence of psychotic symptomatology in a population of cases referred to the Juvenile Court Psychiatric Clinic of the Second District of Connecticut, manifests the necessity for juvenile court systems to be made aware of the possibility of psychosis in our delinquent populations. (CS)

  5. 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

  6. Mexican-Americans in the Southwest.

    Science.gov (United States)

    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…

  7. 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…

  8. 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

  9. Employer Sanctions and the Wages of Mexican Immigrants

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

  12. Effects of Prior Experience on Shelter-Seeking Behavior of Juvenile American Lobsters.

    Science.gov (United States)

    Bayer, Skylar R; Bianchi, Katherine M; Atema, Jelle; Jacobs, Molly W

    2017-04-01

    Shelter-seeking behaviors are vital for survival for a range of juvenile benthic organisms. These behaviors may be innate or they may be affected by prior experience. After hatching, American lobsters Homarus americanus likely first come into contact with shelter during the late postlarval (decapodid) stage, known as stage IV. After the subsequent molt to the first juvenile stage (stage V), they are entirely benthic and are thought to be highly cryptic. We hypothesized that postlarval (stage IV) experience with shelter would carry over into the first juvenile stage (stage V) and reduce the time needed for juveniles to locate and enter shelters (sheltering). We found some evidence of a carryover effect, but not the one we predicted: stage V juveniles with postlarval shelter experience took significantly longer to initiate sheltering. We also hypothesized that stage V juveniles would demonstrate learning by relocating shelters more quickly with immediate prior experience. Our findings were mixed. In a maze, juveniles with immediate prior experience were faster to regain visual contact with shelter, suggesting that they had learned the location of the shelter. In contrast, there was no significant effect of immediate prior experience on time to initiate sheltering in an open arena, or in the maze after juveniles had regained visual contact. We conclude that very young (stage V) juvenile lobsters modify their shelter-seeking behavior based on prior experiences across several timescales. Ecologically relevant variation in habitat exposure among postlarval and early juvenile lobsters may influence successful recruitment in this culturally and commercially important fishery species.

  13. 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)

  14. The Education of Juveniles in Detention: Policy Considerations and Infrastructure Development

    Science.gov (United States)

    Geib, Catherine Foley; Chapman, John F.; D'Amaddio, Amy H.; Grigorenko, Elena L.

    2011-01-01

    This article presents a discussion of the state of affairs pertaining to educating juvenile justice-involved youth. It summarizes general observations regarding the schooling of juveniles in pre-trial and post-trial incarceration settings, as well as, juveniles on probation or in community settings. The article selectively presents relevant…

  15. Juvenile myelomonocytic leukemia presenting as bilateral breast masses

    Energy Technology Data Exchange (ETDEWEB)

    Edison, Michele N.; Letter, Haley P. [Florida Hospital, Department of Radiology, Orlando, FL (United States); University of Central Florida, College of Medicine, Orlando, FL (United States); O' Dell, M.C. [University of Central Florida, College of Medicine, Orlando, FL (United States); Children' s Hospital of Philadelphia, Pediatric Radiology, Philadelphia, PA (United States); Scherer, Kurt; Williams, Jennifer L. [Florida Hospital, Department of Radiology, Orlando, FL (United States); University of Central Florida, College of Medicine, Orlando, FL (United States); Florida State University, College of Medicine, Tallahassee, FL (United States)

    2017-01-15

    An 8-year-old girl presented with bilateral breast masses and was subsequently diagnosed with juvenile myelomonocytic leukemia. Juvenile myelomonocytic leukemia is a rare myelodysplastic syndrome that typically presents in boys younger than 3 years of age with splenomegaly, lymphadenopathy and skin findings. Bilateral breast masses in a child are rare and, as such, present a diagnostic dilemma due to the relative paucity of cases in the literature. We present a case of granulocytic sarcoma of the breasts in a patient with juvenile myelomonocytic leukemia. The authors hope that increased reporting and research regarding pediatric breast masses will help create awareness for such cases. (orig.)

  16. Clinical research of juvenile hyperthyroidism treatment with radioiodine

    International Nuclear Information System (INIS)

    Qiu Ling; Zhang Chunying; Chen Yue

    2001-01-01

    Objective: To evaluate the effects and side effects in the radioiodine management of juvenile hyperthyroidism. Methods: 80 patients with poor effects using anti-thyroid drug were assigned to receive 131 I therapy. The follows of therapy outcome were assessed 1, 3, 6 and 12 months after the start of treatment. One follows up per 1-3 years. Results: Among 80 patients followed by 6 months, clinical response was excellent in 65 patients (81%), good in 15 (19%). There were 12 patients with hypothyroidism followed 4 years, and with no other side effects. Conclusion: The good therapeutic effect was obtained in radioiodine treatment for juvenile hyperthyroidism. Radioiodine was effective to juvenile hyperthyroidism

  17. Juvenile myelomonocytic leukemia presenting as bilateral breast masses

    International Nuclear Information System (INIS)

    Edison, Michele N.; Letter, Haley P.; O'Dell, M.C.; Scherer, Kurt; Williams, Jennifer L.

    2017-01-01

    An 8-year-old girl presented with bilateral breast masses and was subsequently diagnosed with juvenile myelomonocytic leukemia. Juvenile myelomonocytic leukemia is a rare myelodysplastic syndrome that typically presents in boys younger than 3 years of age with splenomegaly, lymphadenopathy and skin findings. Bilateral breast masses in a child are rare and, as such, present a diagnostic dilemma due to the relative paucity of cases in the literature. We present a case of granulocytic sarcoma of the breasts in a patient with juvenile myelomonocytic leukemia. The authors hope that increased reporting and research regarding pediatric breast masses will help create awareness for such cases. (orig.)

  18. 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

  19. A social work study on family related issues influencing juvenile delinquency

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Iravani

    2013-07-01

    Full Text Available We present a study to investigate the impacts of various factors on juvenile delinquency. The study distributes 400 questionnaires among young people aged 19-26 who are involved with some sort of crime and analyzes their feedbacks. There are three hypotheses including family income, tendency to spirituality and religion and educational backgrounds of families and juvenile delinquency among these people. The results show that while family income and religious as well as spirituality characteristics play important role on juvenile delinquency, educational background of the parents do not statistically have any influence on juvenile delinquency. The study recommends that a better family condition could contribute society to reduce juvenile delinquency and people could guide their children through better consultations.

  20. Catch rate of juveniles Ethamatosa fimbriata , Sardinella maderensis ...

    African Journals Online (AJOL)

    We collected data on the quantity of juvenile fish and the daily duration of fishing trips in four landing sites over a two-week period Bernoulli random variables and properties of uniform distribution were used to analyze the data. Catch rates of juveniles Ethamatosa fimbriata, Sardinella maderensis, and Brachydeuterus ...

  1. Extinguishing All Hope: Life-without-Parole for Juveniles

    Science.gov (United States)

    Butler, Frank

    2010-01-01

    Sentencing juveniles to life-without-parole (JLWOP) is a practice fraught with ethical dilemmas. Through in-depth interviews with 11 men living sentences of JLWOP, their narratives of their backgrounds and experiences as juveniles were studied. Common themes were identified, and 3 general categories of cases emerged from the narratives. Ethical…

  2. Setting a minimum age for juvenile justice jurisdiction in California.

    Science.gov (United States)

    S Barnert, Elizabeth; S Abrams, Laura; Maxson, Cheryl; Gase, Lauren; Soung, Patricia; Carroll, Paul; Bath, Eraka

    2017-03-13

    Purpose Despite the existence of minimum age laws for juvenile justice jurisdiction in 18 US states, California has no explicit law that protects children (i.e. youth less than 12 years old) from being processed in the juvenile justice system. In the absence of a minimum age law, California lags behind other states and international practice and standards. The paper aims to discuss these issues. Design/methodology/approach In this policy brief, academics across the University of California campuses examine current evidence, theory, and policy related to the minimum age of juvenile justice jurisdiction. Findings Existing evidence suggests that children lack the cognitive maturity to comprehend or benefit from formal juvenile justice processing, and diverting children from the system altogether is likely to be more beneficial for the child and for public safety. Research limitations/implications Based on current evidence and theory, the authors argue that minimum age legislation that protects children from contact with the juvenile justice system and treats them as children in need of services and support, rather than as delinquents or criminals, is an important policy goal for California and for other national and international jurisdictions lacking a minimum age law. Originality/value California has no law specifying a minimum age for juvenile justice jurisdiction, meaning that young children of any age can be processed in the juvenile justice system. This policy brief provides a rationale for a minimum age law in California and other states and jurisdictions without one.

  3. 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…

  4. 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.

  5. The Juvenile Transition: A Developmental Switch Point in Human Life History

    Science.gov (United States)

    Del Giudice, Marco; Angeleri, Romina; Manera, Valeria

    2009-01-01

    This paper presents a new perspective on the transition from early to middle childhood (i.e., human juvenility), investigated in an integrative evolutionary framework. Juvenility is a crucial life history stage, when social learning and interaction with peers become central developmental functions; here it is argued that the "juvenile transition"…

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

    Directory of Open Access Journals (Sweden)

    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.

  7. 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

  8. Sexual dimorphism and plumage characteristics of juvenile Cape ...

    African Journals Online (AJOL)

    Juveniles, or birds in their first year, were genetically sexed. Standardised photographs were taken of plucked juvenile breast feathers and analysed using Adobe Photoshop. Pixel counts were taken to analyse the streak coverage of a single feather. A scale from 0 to 3 was used to score streak intensity of the entire breast.

  9. Pattern of juvenile periodontitis in Lagos University Teaching ...

    African Journals Online (AJOL)

    Objective: The aim of the survey was to study the pattern of juvenile periodontitis patients that presented at the Lagos University Teaching Hospital Dental Centre from November 1999 to March 2004. Methods: Through review of case files of patients, twenty six juvenile periodontitis patients, within the age range of 18 and 30 ...

  10. Giant Bilateral Juvenile Fibroadenoma of the Breast in Prepubescent Girl.

    Science.gov (United States)

    Khan, Salma; Khan, Momna; Rafique, Sadia

    2015-10-01

    Juvenile fibroadenoma accounts for 4% of the total fibroadenomas. Giant juvenile fibroadenoma is found in only 0.5% of all fibroadenomas. The authors report a 10-year girl presenting with progressive enlargement of both breasts for one year. Based on clinical findings and Fine Needle Aspiration Cytology (FNAC), a diagnosis of bilateral giant juvenile fibroadenomas of breast was made. She underwent bilateral lumpectomy with breast conservation and made uneventful postoperative recovery.

  11. 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

  12. Reassessing the Anatomic Origin of the Juvenile Nasopharyngeal Angiofibroma.

    Science.gov (United States)

    McKnight, Colin D; Parmar, Hemant A; Watcharotone, Kuanwong; Mukherji, Suresh K

    A modern imaging review is necessary to further define the anatomic origin of the juvenile nasopharyngeal angiofibroma. After institutional review board approval, a search from January 1998 to January 2013 yielded 33 male patients (aged 10-23 years) with pathologically proven juvenile nasopharyngeal angiofibroma lesions, as well as pretreatment computed tomography/magnetic resonance imaging. Juvenile nasopharyngeal angiofibroma involvement was assessed in the following regions: sphenopalatine foramen, pterygopalatine fossa, vidian canal, nasopharynx, nasal cavity, sphenoid sinus, choana, pterygomaxillary fissure/masticator space, orbit, and sphenoid bone. The choana and nasopharynx were involved in all 33 patients. In contrast, only 22 lesions involved the pterygopalatine fossa, 24 lesions involved the sphenopalatine foramen, and 28 lesions involved the vidian canal. Our results suggest that the juvenile nasopharyngeal angiofibroma origin is in the region of the choana and nasopharynx rather than the sphenopalatine foramen or pterygopalatine fossa.

  13. 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...

  14. Crocodylus acutus (American Crocodile). Long distance juvenile movement

    Science.gov (United States)

    Crespo, Rafael; Beauchamp, Jeffrey S.; Mazzotti, Frank; Cherkiss, Michael S.

    2015-01-01

    Crocodylus acutus (American Crocodile) is the most widely distributed New World crocodilian species with its range extending from Peru in the south to the southern tip of peninsular Florida in the north. Crocodylus acutus occupies primarily coastal brackish water habitat, however it also occurs in freshwater to hypersaline habitats (Thorbjarnarson 2010. In Crocodiles. Status Survey and Conservation Action Plan. [Third Edition], American Crocodile Crocodylus acutus, pp. 46–53 S.C. Manolis and C. Stevenson. Crocodile Specialist Group, Darwin). There is limited literature on long distance movements of juvenile crocodilians worldwide and no literature on juvenile crocodiles in Florida. However, adult C. acutus in Florida have been documented to make seasonal movements of 5–15 km from preferred foraging habitat to nesting beaches (Mazzotti 1983. The Ecology of Crocodylus acutus in Florida. PhD Dissertation. The Pennsylvania State University, University Park, Pennsylvania. 161pp), and one adult was documented making a 35 km trip from her nest site to preferred foraging habitat (Cherkiss et. al. 2006. Herpetol. Rev. 38:72–73). Rodda (1984. Herpetologica 40:444–451) reported on juvenile C. acutus movement in Gatun Lake, Panama, and found that juveniles stayed within 1 km of their nest site for the first month. Movements of juvenile Crocodylus porosus (Saltwater Crocodile) in a river system in Northern Australia showed a maximum movement of 38.9 km from a known nest site, with the majority of the crocodiles staying within 15.6 km downstream to 6.8 km upstream (Webb and Messel 1978. Aust. Wildlife Res. 5:263–283). Juvenile movement of Crocodylus niloticus (Nile Crocodile) in Lake Ngezi, Zimbabwe showed crocodiles restricted their movements from 1.0 km up to 4.5 km through the wet and dry seasons (Hutton 1989. Am. Zool. 29:1033–1049). Long distance movements of alligators were recorded for sizes ranging from 28 cm to 361 cm in a coastal refuge in Louisiana, where

  15. Musculoskeletal MRI findings of juvenile localized scleroderma

    Energy Technology Data Exchange (ETDEWEB)

    Eutsler, Eric P. [Nemours Children' s Health System/Alfred I. duPont Hospital for Children, Wilmington, DE (United States); Washington University School of Medicine, Mallinckrodt Institute of Radiology, St. Louis, MO (United States); Horton, Daniel B. [Nemours Children' s Health System/Alfred I. duPont Hospital for Children, Division of Rheumatology, Department of Pediatrics, Wilmington, DE (United States); Rutgers Robert Wood Johnson Medical School, Department of Pediatrics, New Brunswick, NJ (United States); Epelman, Monica [Nemours Children' s Health System/Nemours Children' s Hospital, Department of Medical Imaging, Orlando, FL (United States); Finkel, Terri [Nemours Children' s Health System/Nemours Children' s Hospital, Department of Pediatrics, Orlando, FL (United States); Averill, Lauren W. [Nemours Children' s Health System/Alfred I. duPont Hospital for Children, Wilmington, DE (United States)

    2017-04-15

    Juvenile localized scleroderma comprises a group of autoimmune conditions often characterized clinically by an area of skin hardening. In addition to superficial changes in the skin and subcutaneous tissues, juvenile localized scleroderma may involve the deep soft tissues, bones and joints, possibly resulting in functional impairment and pain in addition to cosmetic changes. There is literature documenting the spectrum of findings for deep involvement of localized scleroderma (fascia, muscles, tendons, bones and joints) in adults, but there is limited literature for the condition in children. We aimed to document the spectrum of musculoskeletal magnetic resonance imaging (MRI) findings of both superficial and deep juvenile localized scleroderma involvement in children and to evaluate the utility of various MRI sequences for detecting those findings. Two radiologists retrospectively evaluated 20 MRI studies of the extremities in 14 children with juvenile localized scleroderma. Each imaging sequence was also given a subjective score of 0 (not useful), 1 (somewhat useful) or 2 (most useful for detecting the findings). Deep tissue involvement was detected in 65% of the imaged extremities. Fascial thickening and enhancement were seen in 50% of imaged extremities. Axial T1, axial T1 fat-suppressed (FS) contrast-enhanced and axial fluid-sensitive sequences were rated most useful. Fascial thickening and enhancement were the most commonly encountered deep tissue findings in extremity MRIs of children with juvenile localized scleroderma. Because abnormalities of the skin, subcutaneous tissues and fascia tend to run longitudinally in an affected limb, axial T1, axial fluid-sensitive and axial T1-FS contrast-enhanced sequences should be included in the imaging protocol. (orig.)

  16. Musculoskeletal MRI findings of juvenile localized scleroderma

    International Nuclear Information System (INIS)

    Eutsler, Eric P.; Horton, Daniel B.; Epelman, Monica; Finkel, Terri; Averill, Lauren W.

    2017-01-01

    Juvenile localized scleroderma comprises a group of autoimmune conditions often characterized clinically by an area of skin hardening. In addition to superficial changes in the skin and subcutaneous tissues, juvenile localized scleroderma may involve the deep soft tissues, bones and joints, possibly resulting in functional impairment and pain in addition to cosmetic changes. There is literature documenting the spectrum of findings for deep involvement of localized scleroderma (fascia, muscles, tendons, bones and joints) in adults, but there is limited literature for the condition in children. We aimed to document the spectrum of musculoskeletal magnetic resonance imaging (MRI) findings of both superficial and deep juvenile localized scleroderma involvement in children and to evaluate the utility of various MRI sequences for detecting those findings. Two radiologists retrospectively evaluated 20 MRI studies of the extremities in 14 children with juvenile localized scleroderma. Each imaging sequence was also given a subjective score of 0 (not useful), 1 (somewhat useful) or 2 (most useful for detecting the findings). Deep tissue involvement was detected in 65% of the imaged extremities. Fascial thickening and enhancement were seen in 50% of imaged extremities. Axial T1, axial T1 fat-suppressed (FS) contrast-enhanced and axial fluid-sensitive sequences were rated most useful. Fascial thickening and enhancement were the most commonly encountered deep tissue findings in extremity MRIs of children with juvenile localized scleroderma. Because abnormalities of the skin, subcutaneous tissues and fascia tend to run longitudinally in an affected limb, axial T1, axial fluid-sensitive and axial T1-FS contrast-enhanced sequences should be included in the imaging protocol. (orig.)

  17. Musculoskeletal MRI findings of juvenile localized scleroderma.

    Science.gov (United States)

    Eutsler, Eric P; Horton, Daniel B; Epelman, Monica; Finkel, Terri; Averill, Lauren W

    2017-04-01

    Juvenile localized scleroderma comprises a group of autoimmune conditions often characterized clinically by an area of skin hardening. In addition to superficial changes in the skin and subcutaneous tissues, juvenile localized scleroderma may involve the deep soft tissues, bones and joints, possibly resulting in functional impairment and pain in addition to cosmetic changes. There is literature documenting the spectrum of findings for deep involvement of localized scleroderma (fascia, muscles, tendons, bones and joints) in adults, but there is limited literature for the condition in children. We aimed to document the spectrum of musculoskeletal magnetic resonance imaging (MRI) findings of both superficial and deep juvenile localized scleroderma involvement in children and to evaluate the utility of various MRI sequences for detecting those findings. Two radiologists retrospectively evaluated 20 MRI studies of the extremities in 14 children with juvenile localized scleroderma. Each imaging sequence was also given a subjective score of 0 (not useful), 1 (somewhat useful) or 2 (most useful for detecting the findings). Deep tissue involvement was detected in 65% of the imaged extremities. Fascial thickening and enhancement were seen in 50% of imaged extremities. Axial T1, axial T1 fat-suppressed (FS) contrast-enhanced and axial fluid-sensitive sequences were rated most useful. Fascial thickening and enhancement were the most commonly encountered deep tissue findings in extremity MRIs of children with juvenile localized scleroderma. Because abnormalities of the skin, subcutaneous tissues and fascia tend to run longitudinally in an affected limb, axial T1, axial fluid-sensitive and axial T1-FS contrast-enhanced sequences should be included in the imaging protocol.

  18. 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

  19. 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).

  20. 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.

  1. Effect of TBT on Ruditapes decussatus juveniles.

    Science.gov (United States)

    Coelho, M R; Langston, W J; Bebianno, M J

    2006-06-01

    The effects of sublethal concentrations of tributyltin (TBT) on growth of juvenile clams Ruditapes decussatus were determined during exposure to TBT concentrations of 50, 100 and 250 ng l(-1) (as Sn) for a period up to two years. Length and weight of clams increased continuously in all treatments throughout the experimental period, and, overall, rates were not significantly influenced by TBT exposure, although final length and weight were inversely related to increasing TBT concentration. Juvenile R. decussatus therefore appear to be less sensitive to TBT than larval stages. Some juveniles exposed to TBT developed abnormal shell growth, laterally, changing the typical flattened shape of clams into a more "rounded" form. This characteristic was more visible in the anterior margins of valves than posteriorly, and mainly observed in clams exposed to TBT at 50 ng l(-1) (as Sn).

  2. 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)

  3. 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 ...

  4. Change in Family Structure and Rates of Violent Juvenile Delinquency

    OpenAIRE

    Fry, Jeannie A

    2010-01-01

    This paper addresses the question: Have the changes in family structure in the U.S. become a catalyst for juvenile delinquency? For this research, I use existing statistics for my three independent variables: divorce rates, rate of working mothers with children under age 18, percent female-headed households. My dependent variable, juvenile violent crime rates, is measured using data from the Office of Juvenile Justice and Delinquency Prevention. My control variables consist of the followin...

  5. 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...

  6. Setting a minimum age for juvenile justice jurisdiction in California

    Science.gov (United States)

    Barnert, Elizabeth S.; Abrams, Laura S.; Maxson, Cheryl; Gase, Lauren; Soung, Patricia; Carroll, Paul; Bath, Eraka

    2018-01-01

    Purpose Despite the existence of minimum age laws for juvenile justice jurisdiction in 18 US states, California has no explicit law that protects children (i.e. youth less than 12 years old) from being processed in the juvenile justice system. In the absence of a minimum age law, California lags behind other states and international practice and standards. The paper aims to discuss these issues. Design/methodology/approach In this policy brief, academics across the University of California campuses examine current evidence, theory, and policy related to the minimum age of juvenile justice jurisdiction. Findings Existing evidence suggests that children lack the cognitive maturity to comprehend or benefit from formal juvenile justice processing, and diverting children from the system altogether is likely to be more beneficial for the child and for public safety. Research limitations/implications Based on current evidence and theory, the authors argue that minimum age legislation that protects children from contact with the juvenile justice system and treats them as children in need of services and support, rather than as delinquents or criminals, is an important policy goal for California and for other national and international jurisdictions lacking a minimum age law. Originality/value California has no law specifying a minimum age for juvenile justice jurisdiction, meaning that young children of any age can be processed in the juvenile justice system. This policy brief provides a rationale for a minimum age law in California and other states and jurisdictions without one. Paper type Conceptual paper PMID:28299968

  7. 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…

  8. 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…

  9. 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 [ ...

  10. Marine nurseries and effective juvenile habitats: concepts and applications.

    NARCIS (Netherlands)

    Dahlgren, C.P.; Kellison, G.T.; Adams, A.J.; Gillanders, B.M.; Kendall, M.S.; Layman, C.A.; Ley, J.A.; Nagelkerken, I.; Serafy, J.E.

    2006-01-01

    Much recent attention has been focused on juvenile fish and invertebrate habitat use, particularly defining and identifying marine nurseries. The most significant advancement in this area has been the development of a standardized framework for assessing the relative importance of juvenile habitats

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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.

  16. 75 FR 70293 - Meeting of the Federal Advisory Committee on Juvenile Justice

    Science.gov (United States)

    2010-11-17

    ... DEPARTMENT OF JUSTICE Office of Justice Programs [OJP (OJJDP) Docket No. 1532] Meeting of the Federal Advisory Committee on Juvenile Justice AGENCY: Office of Juvenile Justice and Delinquency Prevention, Office of Justice Programs, Justice. ACTION: Notice of Meeting. SUMMARY: The Office of Juvenile...

  17. Juvenile delinquency in Russia: Ccriminal justice, trends, key issues

    Directory of Open Access Journals (Sweden)

    Kovačević Milica

    2015-01-01

    Full Text Available In the literature, as well as in international statistical surveys, we can rarely find more detailed information on juvenile delinquency in the Russian Federation, as well as on the criminal reaction towards juvenile offenders. Due to the turbulent conditions and great social turmoil which took place in the last few decades in this country, there should be a greater interest in the problem of juvenile delinquency. For Serbia, the experience of the Russian Federation could be especially important if one bears in mind that our country is still going through a transition, population stratification and through economic crisis, and also that Serbia and the Russian Federation share some cultural and religious similarities. Therefore, the aim of this paper is to present, in the summary way, the basic features of juvenile delinquency and the criminal justice system, and thereby build a basis for future research and comparison.

  18. 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.

  19. Radioangiography in diagnosis of juvenile angiofibroma

    International Nuclear Information System (INIS)

    Kalantarov, K.D.; Anyutin, R.G.; Ashikhmina, I.G.

    1979-01-01

    To study the blood supply of juvenile angiofibroma of the nasopharynx 10 patients were examined (2 of them were examined twice). Four patients with the deseases of the nose and the nasopharynx of a nonvascular nature were in the control group. The authors used sup(99m)Tc for radioangiography. The investigations were made on the gamma-chamber ''Nuclear-Chicago'' connected to the computer ''Cina-200''. Ten patients with juvenile angiofibroma of the nasopharynx showed rapid accumulation of the radioactive substance at the site of the tumour exceeding its concentration in the carotic arteries by 4-10 times. In unilateral localization of angiofibroma, its blood supply was provided mainly through the external carotic artery at the affection site or evenly through the both external carotic arteries. The data on dynamic distribution of the radioactive substance, scintiphotograms and clinical observations allow a distinct differentiation between juvenile angiofibroma of the nasopharynx the adenoid tissue or any other tumour to determine the angiofibroma size as well as to follow the results of surgical and radiation treatment

  20. 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.

  1. 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.

  2. 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

  3. 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…

  4. 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…

  5. 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.

  6. Social skills training for juvenile delinquents : post-treatment changes

    NARCIS (Netherlands)

    van der Stouwe, Trudy; Asscher, Jessica J.; Hoeve, Machteld; van der Laan, Peter H.; Stams, Geert Jan J M

    2016-01-01

    Objectives: To examine the post-treatment effectiveness of an outpatient, individual social skills training for juvenile delinquents in the Netherlands and to conduct moderator tests for age, gender, ethnicity, and risk of reoffending. Methods: The sample consisted of juveniles who received Tools4U,

  7. Social Skills Training for Juvenile Delinquents: Post-Treatment Changes

    NARCIS (Netherlands)

    van der Stouwe, Trudy; Asscher, J.J.; Stams, G.J.J.M.; Hoeve, M.; van der Laan, Peter H.

    2016-01-01

    Objectives: To examine the post-treatment effectiveness of an outpatient, individual social skills training for juvenile delinquents in the Netherlands and to conduct moderator tests for age, gender, ethnicity, and risk of reoffending. Methods: The sample consisted of juveniles who received Tools4U,

  8. Social skills training for juvenile delinquents : Post-treatment changes

    NARCIS (Netherlands)

    van der Stouwe, T.; Asscher, J.J.; Hoeve, M.; van der Laan, P.H.; Stams, G.J.J.M.

    2016-01-01

    Objectives To examine the post-treatment effectiveness of an outpatient, individual social skills training for juvenile delinquents in the Netherlands and to conduct moderator tests for age, gender, ethnicity, and risk of reoffending. Methods The sample consisted of juveniles who received Tools4U, a

  9. 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.

  10. 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.

  11. 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.

  12. Tracking from the tropics reveals behaviour of juvenile songbirds on their first spring migration.

    Directory of Open Access Journals (Sweden)

    Emily A McKinnon

    Full Text Available Juvenile songbirds on spring migration travel from tropical wintering sites to temperate breeding destinations thousands of kilometres away with no prior experience to guide them. We provide a first glimpse at the migration timing, routes, and stopover behaviour of juvenile wood thrushes (Hylocichla mustelina on their inaugural spring migration by using miniaturized archival geolocators to track them from Central America to the U.S. and Canada. We found significant differences between the timing of juvenile migration and that of more experienced adults: juveniles not only departed later from tropical wintering sites relative to adults, they also became progressively later as they moved northward. The increasing delay was driven by more frequent short stops by juveniles along their migration route, particularly in the U.S. as they got closer to breeding sites. Surprisingly, juveniles were just as likely as adults to cross the Gulf of Mexico, an open-water crossing of 800-1000 km, and migration route at the Gulf was not significantly different for juveniles relative to adults. To determine if the later departure of juveniles was related to poor body condition in winter relative to adults, we examined percent lean body mass, fat scores, and pectoral muscle scores of juvenile versus adult birds at a wintering site in Belize. We found no age-related differences in body condition. Later migration timing of juveniles relative to adults could be an adaptive strategy (as opposed to condition-dependent to avoid the high costs of fast migration and competition for breeding territories with experienced and larger adults. We did find significant differences in wing size between adults and juveniles, which could contribute to lower flight efficiency of juveniles and thus slower overall migration speed. We provide the first step toward understanding the "black box" of juvenile songbird migration by documenting their migration timing and en route performance.

  13. Martial arts participation and externalizing behavior in juveniles : A meta-analytic review

    NARCIS (Netherlands)

    Gubbels, J.; van der Stouwe, T.; Spruit, A.; Stams, G.J.J.M.

    2016-01-01

    Martial arts are very popular among juveniles all over the world, but the relation between martial arts and externalizing behavior in juveniles remains unclear. The current multilevel meta-analysis of 12 studies, including 94 effect sizes and N = 5949 juveniles, was conducted to examine the relation

  14. CORRELATION BETWEEN FAMILY COMMUNICATION PATTERNS AND JUVENILE DELINQUENCY IN JUNIOR HIGH SCHOOL

    Directory of Open Access Journals (Sweden)

    Zurriyatun Thoyibah

    2017-08-01

    Full Text Available Background: Adolescents who are in transition period have high risk behavior of juvenile delinquency. Communication between parents and adolescents effectively and openly could help adolescents to avoid delinquency behavior. Objective: This study aims to examine the relationship between family communication patterns and juvenile delinquency in Junior High School. Methods: This research employed a cross-sectional design with correlation description approach. There were 243 students selected using simple random sampling from the 7th and 8th grade students of Junior High School. A questionnaire of juvenile delinquency and family communication pattern were used in this study. Data were analyzed using Chi Square test. Result: The research showed that the majority juvenile delinquency category was low (65% and the majority of communication pattern was in functional category (73.3%. There was a significant relationship between family communication pattern and juvenile delinquency (p<0.05. Conclusion: Communication pattern within family have significant association with juvenile delinquency.

  15. 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…

  16. 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.

  17. 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.

  18. Cardiac juvenile xanthogranuloma in an infant presenting with pericardial effusion.

    Science.gov (United States)

    Kobayashi, Daisuke; Delius, Ralph E; Debelenko, Larisa V; Aggarwal, Sanjeev

    2013-01-01

    Juvenile xanthogranuloma is a rare histiocytic disorder of childhood mainly affecting skin and rarely deep soft tissues and viscera. We report a 2-month-old infant who presented with respiratory distress secondary to a large pericardial effusion associated with an epicardial mass. Excisional biopsy was performed and the mass was diagnosed as juvenile xanthogranuloma. The child is well without evidence of disease 8 months following the excision. The corresponding literature on juvenile xanthogranuloma with cardiac manifestations is reviewed. © 2012 Wiley Periodicals, Inc.

  19. 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…

  20. Angiofibroma juvenil nasofaríngeo Juvenile nasopharyngeal angiofibroma

    Directory of Open Access Journals (Sweden)

    Juan Gualberto Lescaille Torres

    2012-06-01

    Full Text Available Se presenta el caso de un angiofibroma juvenil nasofaríngeo, en un paciente del consultorio médico No. 9, que pertenece al Policlínico Integral Docente "Carlos Manuel Portuondo" de Marianao. Se reconoce la importancia de realizar una historia clínica detallada, así como un minucioso examen físico, por el médico de familia y el otorrinolaringólogo del área de salud, que incluyó la rinoscopia posterior, para poder llegar al diagnóstico de esa patología, y realizar la extirpación precoz del angiofibroma, mediante el proceder quirúrgico. Se concluyó que el diagnóstico clínico se correspondió con el histopatológico, y que la conducta quirúrgica temprana es resolutiva en la afección.It is presented a case of juvenile nasopharyngeal angiofibroma in a patient with this pathology, from the clicial practice No. 9, in Comprehensive Teaching Polyclinic "Carlos Manuel Portuondo" in Marianao. It recognizes the importance of a thorough clinical history and careful physical examination by the family physician and the otolaryngologist in this health area, including a posterior rhinoscopy, to diagnose this disease and to achieve early removal of the angiofibroma, by a surgical procedure. It was concluded that the clinical diagnosis corresponded to the histopathological diagnosis, and that early surgical treatment is resolute in this condition.