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1.
J Endocrinol Invest ; 47(2): 401-410, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37450195

RESUMEN

PURPOSE: Preliminary data suggested that bone mineral density (BMD) in transgender adults before initiating gender-affirming hormone therapy (GAHT) is lower when compared to cisgender controls. In this study, we analyzed bone metabolism in a sample of transgender adults before GAHT, and its possible correlation with biochemical profile, body composition and lifestyle habits (i.e., tobacco smoke and physical activity). METHODS: Medical data, smoking habits, phospho-calcic and hormonal blood tests and densitometric parameters were collected in a sample of 125 transgender adults, 78 Assigned Females At Birth (AFAB) and 47 Assigned Males At Birth (AMAB) before GAHT initiation and 146 cisgender controls (57 females and 89 males) matched by sex assigned at birth and age. 55 transgender and 46 cisgender controls also underwent a complete body composition evaluation and assessment of physical activity using the International Physical Activity Questionnaire (IPAQ). RESULTS: 14.3% of transgender and 6.2% of cisgender sample, respectively, had z-score values < -2 (p = 0.04). We observed only lower vitamin D values in transgender sample regarding biochemical/hormonal profile. AFAB transgender people had more total fat mass, while AMAB transgender individuals had reduced total lean mass as compared to cisgender people (53.94 ± 7.74 vs 58.38 ± 6.91, p < 0.05). AFAB transgender adults were more likely to be active smokers and tend to spend more time indoor. Fat Mass Index (FMI) was correlated with lumbar and femur BMD both in transgender individuals, while no correlations were found between lean mass parameters and BMD in AMAB transgender people. CONCLUSIONS: Body composition and lifestyle factors could contribute to low BMD in transgender adults before GAHT.


Asunto(s)
Personas Transgénero , Transexualidad , Masculino , Adulto , Femenino , Recién Nacido , Humanos , Densidad Ósea , Transexualidad/tratamiento farmacológico , Identidad de Género , Composición Corporal
2.
J Exp Bot ; 63(12): 4485-96, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22685306

RESUMEN

This study analyses the signalling pathways triggered by nitric oxide (NO) in response to ozone (O(3)) fumigation of tobacco plants, with particular attention to protein kinase cascades and free cytosolic Ca(2+) in defence-gene activation. NO was visualized with the NO probe DAF-FM. Using a pharmacological approach, the effects of different inhibitors on the expression profiles of NO-dependent defence genes were monitored using RT-PCR. The assay of the kinase activity of the immunoprecipitates complexes shows that O(3) stimulates a 48 kDa salicylic acid (SA)-induced protein kinase (SIPK) in an NO-dependent manner. The O(3)-induced alternative oxidase 1a (AOX1a) and phenylalanine ammonia lyase a (PALa) genes are modulated by phosphorylation by protein kinases, and SIPK might have a role in this up-regulation. By contrast, protein dephosphorylation mediates pathogenesis-related protein 1a (PR1a) expression in O(3)-treated tobacco plants. Ca(2+) is essential, but not sufficient, to promote NO accumulation in ozonated tobacco plants. Intracellular Ca(2+) transients are also essential for PALa up-regulation and cGMP-induced PR1a expression. Partial dependence on intracellular Ca(2+) suggests two different pathways of SA accumulation and PR1a induction. A model summarizing the signalling networks involving NO, SA, and the cellular messengers in this O(3)-induced defence gene activation is proposed.


Asunto(s)
Calcio/metabolismo , Nicotiana/fisiología , Óxido Nítrico/farmacología , Ozono/farmacología , Proteínas Quinasas/metabolismo , Transducción de Señal/efectos de los fármacos , Supervivencia Celular , GMP Cíclico/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/genética , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Modelos Biológicos , Óxido Nítrico/metabolismo , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Fenilanina Amoníaco-Liasa/genética , Fenilanina Amoníaco-Liasa/metabolismo , Fosforilación , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Proteínas Quinasas/genética , Ácido Salicílico/metabolismo , Transducción de Señal/genética , Nicotiana/efectos de los fármacos , Nicotiana/genética , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/genética
3.
Environ Pollut ; 212: 559-564, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26977961

RESUMEN

Ethylenediurea (EDU) is a common research tool for investigating ozone impacts on vegetation, although the role of different application routes (foliar spray vs soil drench) on EDU persistence in the leaves is unknown. We quantified EDU concentrations in leaves of the O3-sensitive Bel-W3 cultivar of tobacco treated with EDU as either foliar spray or soil drench. Foliar EDU concentrations were measured by Q-TOF LC/MS. When EDU was applied as foliar spray, 1 h was enough for reaching a measurable concentration within the leaf. EDU concentration increased over the 21-day period when the leaf was not washed after the application (treatment #1), while it decreased when the leaf was washed after the application (treatment #2). These results suggest that: a) dry deposition of EDU onto the leaf surface was gradually absorbed into the unwashed leaf, although the mechanisms of such uptake were unclear; b) concentration of EDU was decreased quickly (-35%) during the first 24 h from application and more slowly during the following three days (-20%) in the washed leaves. Degradation did not involve enzymatic reactions and was not affected by the presence of ROS. When EDU was applied as soil drench, foliar concentrations increased over time, likely due to adsorption onto soil organic matter and gradual re-solubilization by irrigation water. An analysis of EDU concentration in protoplast and intercellular washing fluid showed that EDU did not enter the cells, but was retained in the apoplast only. Possible implications of EDU in the apoplast and recommendations for EDU application are discussed.


Asunto(s)
Nicotiana/metabolismo , Compuestos de Fenilurea/metabolismo , Hojas de la Planta/metabolismo , Aerosoles , Contaminantes Atmosféricos/metabolismo , Ozono/metabolismo , Suelo , Factores de Tiempo
4.
Biochim Biophys Acta ; 1037(1): 73-80, 1990 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-2294973

RESUMEN

The major acid phosphatase form (orthophosphoric-monoester phosphohydrolase (acid optimum), EC 3.1.3.2) was purified from the soluble extract of barley roots. The enzyme is homogeneous on polyacrylamide gel electrophoresis and moves as a single band of Mr approximately 38,000 in the presence of sodium dodecyl sulphate. The molecular weight of the native enzyme was Mr 77,600 and 79,000 as determined, respectively, by gel filtration on a Sephadex G-100 column and by density gradient ultracentrifugation. The isoelectric point was about 6.28. The enzyme is competitively inhibited by molybdate (Ki = 9 x 10(-7) M). NaF, Ag(+), Hg(2+), Pb(2+) and Zn(2+) are also inhibitors, while other cations showed no effect. The enzyme hydrolyzes a wide variety of natural and synthetic phosphate esters. In particular, the enzyme seems to be active on ATP, o-phosphotyrosine, o-phosphoserine and glucose 1-phosphate. The pH dependence studies between pH 4-8 using p-nitrophenylphosphate as substrate and diethylpyrocarbonate inactivation indicate the presence of essential histidine residue at the active site.


Asunto(s)
Fosfatasa Ácida/aislamiento & purificación , Grano Comestible/enzimología , Hordeum/enzimología , Fosfatasa Ácida/antagonistas & inhibidores , Fosfatasa Ácida/metabolismo , Cationes/farmacología , Cromatografía en Gel , Cromatografía por Intercambio Iónico , Citoplasma/enzimología , Calor , Concentración de Iones de Hidrógeno , Isoenzimas/aislamiento & purificación , Isoenzimas/metabolismo , Cinética , Peso Molecular , Especificidad por Sustrato
5.
Free Radic Res ; 31 Suppl: S67-73, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10694043

RESUMEN

Plants of Nicotiana tabacum (O3-tolerant cv Bel-B and O3-sensitive cv Bel-W3) were exposed to 150 ppb of ozone for 5 h; the fumigation produced visual injury in mature leaves, particularly in Bel-W3. After O3-treatment the pigments of the xanthophyll cycle pool decreased in both cvs, with a strong reduction in violaxanthin content, while antheraxanthin and zeaxanthin increased slightly. Under these conditions the content of leaf abscisic acid (ABA) markedly increased, particularly in O3-sensitive cv, indicating that the violaxanthin may have been partially converted into ABA. The control plants of Bel-B showed an ascorbic acid content four times greater than Bel-W3 and the ozone treatment did not produce significant differences in the ascorbic acid content and in the redox state. The two tobacco cvs were found to have similar total glutathione content, however the redox state was lower in O3-sensitive cv and decreased after ozone exposure. Ozone fumigation caused an increase in oxidized glutathione, particularly in Bel-W3, associated with a reduced glutathione reductase (GR) activity and a reduced GR protein content.


Asunto(s)
Ácido Ascórbico/metabolismo , Glutatión/metabolismo , Luteína/metabolismo , Nicotiana/efectos de los fármacos , Nicotiana/metabolismo , Ozono/toxicidad , Plantas Tóxicas , Xantófilas , Carotenoides/análogos & derivados , Carotenoides/metabolismo , Radicales Libres/metabolismo , Glutatión Reductasa/metabolismo , Estrés Oxidativo/efectos de los fármacos , Pigmentos Biológicos/metabolismo , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Zeaxantinas , beta Caroteno/análogos & derivados , beta Caroteno/metabolismo
6.
Environ Pollut ; 193: 1-5, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24975117

RESUMEN

Ethylenediurea (EDU) is the most common chemical used to prevent ozone (O3) injury on vegetation. Despite considerable research, its mode of action remains elusive and gene expression has not been studied. Transcripts of major antioxidant enzymes (catalase, glutathione reductase, glutathione peroxidase) were measured for the first time in a model plant (Phaseolus vulgaris cv S156) after short-term O3 exposure (0 or 90 ppb, 5 h/d, 4 days) and a single spray with EDU (0 or 300 ppm). Visible, physiological and biochemical parameters were assessed as indices of O3-induced stress. In O3-exposed EDU-protected plants, levels of transcript, enzyme activity, H2O2 accumulation, gas exchange and foliar visible injury were similar to those in control plants. These results suggest that EDU may halt the O3-induced ROS generation within 24 h from the exposure, and thus the downstream cascade mechanisms leading to increased H2O2 production, impaired gas exchange, and occurrence of leaf lesions.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Ozono/metabolismo , Phaseolus/fisiología , Compuestos de Fenilurea/metabolismo , Sustancias Protectoras/metabolismo , Catalasa/genética , Glutatión Peroxidasa/genética , Glutatión Reductasa/genética , Peróxido de Hidrógeno/metabolismo , Phaseolus/enzimología , Phaseolus/genética , Proteínas de Plantas/genética , Activación Transcripcional
7.
Environ Pollut ; 157(12): 3354-6, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19836119

RESUMEN

Genotoxicity of urban air has been analysed almost exclusively in airborne particulates. We monitored the genotoxic effects of airborne pollutants in the urban air of Perugia (Central Italy). Two plant bioindicators with different genetic endpoints were used: micronuclei in meiotic pollen mother cells using Tradescantia-micronucleus bioassay (Trad-MCN) and DNA damage in nuclei of Nicotiana tabacum leaves using comet assay (Nicotiana-comet). Buds of Tradescantia clone # 4430 and young N. tabacum cv. Xanthi plants were exposed for 24 h at three sites with different pollution levels. One control site (indoor control) was also used. The two bioassays showed different sensitivities toward urban pollutants: Trad-MCN assay was the most sensitive, but DNA damage in N. tabacum showed a better correlation with the pollutant concentrations. In situ biomonitoring of airborne genotoxins using higher plants combined with chemical analysis is thus recommended for characterizing genotoxicity of urban air.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Bioensayo/métodos , Monitoreo del Ambiente/métodos , Nicotiana/efectos de los fármacos , Tradescantia/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Pruebas de Micronúcleos , Pruebas de Mutagenicidad , Nicotiana/genética , Tradescantia/genética , Salud Urbana
8.
Plant Physiol ; 126(3): 993-1000, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11457950

RESUMEN

Isoprene is formed in and emitted by plants and the reason for this apparent carbon waste is still unclear. It has been proposed that isoprene stabilizes cell and particularly chloroplast thylakoid membranes. We tested if membrane stabilization or isoprene reactivity with ozone induces protection against acute ozone exposures. The reduction of visible, physiological, anatomical, and ultrastructural (chloroplast) damage shows that clones of plants sensitive to ozone and unable to emit isoprene become resistant to acute and short exposure to ozone if they are fumigated with exogenous isoprene, and that isoprene-emitting plants that are sensitive to ozone do not suffer damage when exposed to ozone. Isoprene-induced ozone resistance is associated with the maintenance of photochemical efficiency and with a low energy dissipation, as indicated by fluorescence quenching. This suggests that isoprene effectively stabilizes thylakoid membranes. However, when isoprene reacts with ozone within the leaves or in a humid atmosphere, it quenches the ozone concentration to levels that are less or non-toxic for plants. Thus, protection from ozone in plants fumigated with isoprene may be due to a direct ozone quenching rather than to an induced resistance at membrane level. Irrespective of the mechanism, isoprene is one of the most effective antioxidants in plants.


Asunto(s)
Antioxidantes/metabolismo , Butadienos/metabolismo , Hemiterpenos , Ozono/metabolismo , Pentanos , Hojas de la Planta/metabolismo , Rosales , Árboles
9.
Am J Reprod Immunol ; 51(2): 160-5, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14748844

RESUMEN

PROBLEM: CBA/J x DBA/2 abortion rate could be the consequence of a deficient local production of T helper (Th2) cytokines, which cause fetal wastage via fgl2 prothrombinase. Heparin reduces significantly the abortion rate in mice and recurrent spontaneous abortion (RSA) patients. We proposed to determine the effect of enoxaparin on the levels of local interleukin (IL)-6 during murine pregnancy. METHOD OF STUDY: Recombinant human IL-6 (rhIL-6) or enoxaparin were inoculated in CBA/J x DBA/2 pregnant mice on days 6.5-12.5. IL-6 levels in sera as well as in culture supernatants of day 9.5 fetoplacental units of CBA/J x BALB/c control mice or CBA/J x DBA/2 abortion combination were determined by enzyme-linked immunosorbent assay (ELISA) test. RESULTS: CBA/J x DBA/2 fetoplacental units secreted significantly lower levels of IL-6 with regard to CBA/J x BALB/c normal units. rhIL-6h and enoxaparin treatments decreased the resorption rate and regulated IL-6 fetoplacental levels. CONCLUSION: This study suggests that regulation of IL-6 fetoplacental levels could be involved in heparin-mediated anticoagulation protection against abortion.


Asunto(s)
Aborto Espontáneo/tratamiento farmacológico , Heparina de Bajo-Peso-Molecular/uso terapéutico , Interleucina-6/biosíntesis , Interleucina-6/uso terapéutico , Placenta/metabolismo , Aborto Espontáneo/metabolismo , Animales , Técnicas de Cultivo , Femenino , Reabsorción del Feto/tratamiento farmacológico , Ratones , Placenta/citología , Embarazo
10.
Am J Reprod Immunol ; 48(6): 394-403, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12607776

RESUMEN

PROBLEM: To determine the effect of ovarian stimulation on TH1, TH2 and natural killer (NK) lymphocytes, plasma cytokines, leptin and nitrite levels. METHODS: Women with reproductive failure were studied during the implantation window, at baseline (n = 18) and under ovarian stimulation (gonadotropins + progesterone, n = 6). CONTROLS: eight fertile women. Lymphocyte subpopulations and NK function were determined by flow cytometry. Interleukin-2 (IL-2), IL-4, IL-10, IFN-gamma, TNF-alpha, TGF-beta1 and leptin were measured by enzyme immunoassay (EIA); nitrite by the Griess reaction. RESULTS: At baseline, patients had higher values of NK effectors, NK activity and plasma IFN-gamma and IL-2 than controls. Conversely, TGF-beta1 values were lower. Hormones induced leukocytosis. Under stimulation, THI CD4+ cells, NK effectors and function and plasma IFN-gamma and IL-2 decreased, while transforming growth factor (TGF)-beta1 increased. Other variables did not change. CONCLUSION: The abnormal distribution of leukocytes, high TH1 cytokines and a low TGF-beta1 associated with reproductive failure, respond to ovarian stimulation, achieving total or partial normalization.


Asunto(s)
Gonadotropina Coriónica/farmacología , Citocinas/sangre , Infertilidad Femenina/terapia , Células Asesinas Naturales/efectos de los fármacos , Leptina/sangre , Leuprolida/farmacología , Nitritos/sangre , Inducción de la Ovulación , Progesterona/farmacología , Células TH1/efectos de los fármacos , Células Th2/efectos de los fármacos , Adulto , Citotoxicidad Inmunológica , Femenino , Humanos , Inmunofenotipificación , Infertilidad Femenina/sangre , Infertilidad Femenina/inmunología , Interferón gamma/sangre , Interleucina-10/sangre , Interleucina-2/sangre , Interleucina-4/sangre , Células Asesinas Naturales/inmunología , Recuento de Linfocitos , Factor de Crecimiento Transformador beta/sangre , Factor de Crecimiento Transformador beta1 , Factor de Necrosis Tumoral alfa/análisis
11.
Genet. mol. res. (Online) ; 4(2): 143-151, 30 jun. 2005. tab, ilus
Artículo en Inglés | LILACS | ID: lil-445297

RESUMEN

We studied chromosomal abnormalities in arrested embryos produced by assisted reproductive technology with fluorescence in situ hybridization (FISH) and comparative genomic hybridization (CGH) in order to determine the best technique for evaluating chromosomal aneusomies to be implemented in different situations. We examined individual blastomeres from arrested embryos by FISH and arrested whole embryos by CGH. All of the 10 FISH-analyzed embryos gave results, while only 7 of the 30 embryos analyzed by CGH were usable. Fifteen of the 17 embryos were chromosomally abnormal. CGH provided more accurate data for arrested embryos; however, FISH is the technique of choice for screening in preimplantation genetic diagnosis, because the results can be obtained within a day, while the embryos are still in culture.


Asunto(s)
Humanos , Femenino , Embarazo , Hibridación Fluorescente in Situ , Cariotipificación/métodos , Diagnóstico Preimplantación/métodos , Genómica , Trastornos de los Cromosomas/diagnóstico , Trastornos de los Cromosomas/embriología , Trastornos de los Cromosomas/genética , Técnicas Reproductivas Asistidas
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