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1.
Clín. investig. ginecol. obstet. (Ed. impr.) ; 50(3): [100849], Jul-Sep. 2023. ilus
Article in Spanish | IBECS | ID: ibc-223312

ABSTRACT

La insuficiencia ovárica primaria es una condición en la que las mujeres menores de 40años experimentan oligomenorrea o amenorrea durante 4meses o más; esta pérdida temprana de la función ovárica puede estar relacionada con una serie de etiologías, incluidos trastornos genéticos, autoinmunes, infecciones o causas iatrogénicas; no obstante, del 74 al 90% son idiopáticas. A pesar de ser una alteración poco prevalente, es de gran importancia clínica, ya que afecta en múltiples aspectos de la vida a todas las mujeres. En la actualidad se están desarrollando diferentes estudios con el fin de encontrar nuevos blancos moleculares para establecer nuevas terapias para el tratamiento de esta patología.(AU)


Primary ovarian failure is a condition in which women under 40 experience oligomenorrhea or amenorrhea for 4months or longer; this early ovarian function loss may be related to a series of etiologies, including genetic disorders, autoimmune diseases, infections or iatrogenic causes; however 74%-90% are idiopathic. Despite being a less prevalent disorder, it is of great clinical importance since it affects all women in multiple aspects of life. At present, different studies are being developed in order to find new molecular targets to establish new therapies for the treatment of this pathology.(AU)


Subject(s)
Humans , Female , Oligomenorrhea , Amenorrhea , Primary Ovarian Insufficiency/epidemiology , Primary Ovarian Insufficiency/prevention & control , Gynecology , Ovarian Diseases , Quality of Life , Primary Ovarian Insufficiency/diagnosis , Primary Ovarian Insufficiency/physiopathology , Primary Ovarian Insufficiency/therapy
2.
Nature ; 615(7950): 45-49, 2023 03.
Article in English | MEDLINE | ID: mdl-36859580

ABSTRACT

Accretion disks around compact objects are expected to enter an unstable phase at high luminosity1. One instability may occur when the radiation pressure generated by accretion modifies the disk viscosity, resulting in the cyclic depletion and refilling of the inner disk on short timescales2. Such a scenario, however, has only been quantitatively verified for a single stellar-mass black hole3-5. Although there are hints of these cycles in a few isolated cases6-10, their apparent absence in the variable emission of most bright accreting neutron stars and black holes has been a continuing puzzle11. Here we report the presence of the same multiwavelength instability around an accreting neutron star. Moreover, we show that the variability across the electromagnetic spectrum-from radio to X-ray-of both black holes and neutron stars at high accretion rates can be explained consistently if the accretion disks are unstable, producing relativistic ejections during transitions that deplete or refill the inner disk. Such a new association allows us to identify the main physical components responsible for the fast multiwavelength variability of highly accreting compact objects.

3.
Nature ; 603(7899): 52-57, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35236977

ABSTRACT

All disc-accreting astrophysical objects produce powerful disc winds. In compact binaries containing neutron stars or black holes, accretion often takes place during violent outbursts. The main disc wind signatures during these eruptions are blue-shifted X-ray absorption lines, which are preferentially seen in disc-dominated 'soft states'1,2. By contrast, optical wind-formed lines have recently been detected in 'hard states', when a hot corona dominates the luminosity3. The relationship between these signatures is unknown, and no erupting system has as yet revealed wind-formed lines between the X-ray and optical bands, despite the many strong resonance transitions in this ultraviolet (UV) region4. Here we report that the transient neutron star binary Swift J1858.6-0814 exhibits wind-formed, blue-shifted absorption lines associated with C IV, N V and He II in time-resolved UV spectroscopy during a luminous hard state, which we interpret as a warm, moderately ionized outflow component in this state. Simultaneously observed optical lines also display transient blue-shifted absorption. Decomposing the UV data into constant and variable components, the blue-shifted absorption is associated with the former. This implies that the outflow is not associated with the luminous flares in the data. The joint presence of UV and optical wind features reveals a multi-phase and/or spatially stratified evaporative outflow from the outer disc5. This type of persistent mass loss across all accretion states has been predicted by radiation-hydrodynamic simulations6 and helps to explain the shorter-than-expected duration of outbursts7.

4.
J Dairy Sci ; 100(8): 6577-6582, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28601452

ABSTRACT

Video stall lameness scoring (SLS) has been shown to be comparable to video locomotion scoring for evaluating lameness in dairy cows housed in tie-stalls and may be a more practical and easier method to measure lameness in a herd. We compared live SLS to video SLS and to live locomotion scoring. A total of 685 lactating cows subsampled from 27 commercial dairy herds were examined for lameness through live and video SLS. Cows scored with the live or video SLS system were scored for 4 behavioral indicators while still in their stall: weight shifting (shift), standing on the edge of the stall (edge), uneven weight bearing while standing (rest), and uneven weight bearing while moving from side to side (uneven). Two observers live scored and video scored for SLS. Lameness prevalence from video SLS and live SLS were similar (31 vs. 30%, respectively). Prevalence of the behavioral indicators varied from 0.59 to 58.2%. Sensitivity and specificity of live SLS was calculated using video SLS as the gold standard for lameness detection in tie-stalls. Sensitivity of live SLS was 0.83 and specificity was 0.94. False positives and false negatives for lameness were 14.4 and 16.8%, respectively. When comparing the prevalence of lameness measured through video or live SLS at the herd level, live SLS for lameness was correlated to video SLS (r = 0.91) with a Cohen's kappa coefficient of 0.79 (95% confidence limit = 0.73-0.84). Average exact agreement in the behavior indicators observed ranged from 80 to 100%. A subsample of 250 cows from 5 herds were scored for live SLS and live locomotion by a third observer. Intra- and interobserver reliability for live SLS and live locomotion scoring were found to have a kappa coefficient of 0.53 (95% confidence limit = 0.43-0.64) when determining a cow as lame through SLS or locomotion scoring. Live SLS was correlated with live locomotion scoring (r = 0.92). However, lameness prevalence was lower when using live SLS (28.4%) compared with locomotion scoring (38%). In summary, live SLS may be an acceptable method to replace video SLS to identify lame cows and rank tie-stall herds in terms of lameness prevalence without having to remove the cows from their stalls or view videos to score; however, it may underestimate lameness prevalence compared with locomotion scoring methods.


Subject(s)
Cattle Diseases/diagnosis , Gait/physiology , Housing, Animal , Lameness, Animal/diagnosis , Animals , Cattle , Dairying , Female , Lactation , Reproducibility of Results
5.
Plant Biol (Stuttg) ; 18(2): 271-9, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26404733

ABSTRACT

Depending on their specificity to gypsum, plants can be classified as gypsophiles (gypsum exclusive) and gypsovags (non-exclusive). The former may further be segregated into wide and narrow gypsophiles, depending on the breadth of their distribution area. Narrow gypsum endemics have a putative similar chemical composition to plants non-exclusive to gypsum (i.e. gypsovags), which may indicate their similar ecological strategy as stress-tolerant plant refugees on gypsum. However, this hypothesis awaits testing in different regions of the world. We compared the chemical composition of four narrow gypsum endemics, one widely distributed gypsophile and six gypsovags from Turkey. Further, we explored the plasticity in chemical composition of Turkish gypsovags growing on high- and low-gypsum content soils. Differences were explored with multivariate analyses (RDA) and mixed models (REML). Narrow gypsum endemics segregated from gypsovags in their chemical composition according to RDAs (mainly due to higher K and ash content in the former). Nevertheless, differences were small and disappeared when different nutrients were analysed individually. All the gypsovags studied accumulated more S and ash when growing on high-gypsum than on low-gypsum soils. Similar to narrow gypsum endemics from other regions of the world, most local gypsum endemics from Turkey show a similar chemical composition to gypsovags. This may indicate a shared ecological strategy as stress-tolerant plants not specifically adapted to gypsum. Nevertheless, the narrow gypsum endemic Gypsophila parva showed a chemical composition typical of gypsum specialists, indicating that various strategies are feasible within narrowly distributed gypsophiles.


Subject(s)
Calcium Sulfate/pharmacology , Plants/drug effects , Soil/chemistry , Analysis of Variance , Climate , Plant Leaves/chemistry , Plant Leaves/drug effects , Species Specificity , Turkey
6.
J Dairy Sci ; 98(9): 6085-93, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26162795

ABSTRACT

Access to pasture has advantages for cows such as reduced lameness and improved udder health, but also may expose cows to stressors such as extreme heat. The objective of this study was to understand how portable shade affected physiological and behavioral responses of pastured dairy cows in a Canadian summer. Over 8wk, a total of 24 lactating Holstein cows were separated into 2 treatments, one with access to shade and a control without access to shade. The cows were pastured in groups of 4, with 3 field sections per treatment. Instantaneous scan sampling of behaviors (drinking, lying, grazing, other) performed in the shade or not were recorded every 5min for 3h/d during the hottest part of the day (peak hours: 1130-1530h) 3d/wk. Ambient temperature, humidity, and vaginal temperature were recorded at 10-min intervals. Daily milk production was also recorded. Differences between treatments by week were analyzed using the generalized linear mixed model with group as random effect and treatment as fixed effect. Cows with shade access were observed at the water trough up to 6.42 times less and lying down up to 1.75 times more. Cows with shade access grazed up to 1.5 times more but only when the temperature-humidity index was above their comfort threshold (≥72) during the hottest part of the day (wk 2). Cows sought shade when it was made available, but spent less than half of their time observed (%) in the shade (40.8±4.67) with the exception of wk 2 when most of the time was spent under the shade (74.3±4.77). Daily lying time was highest during peak hours for cows with shade access. However, no overall difference in total lying time between the 2 treatments was observed. No differences were found in vaginal temperature or milk production between treatments with the exception of wk 1 for daily milk production, which was higher for cows in the control treatment. In conclusion, cows sought shade when it was provided at pasture, whereas cows without access to shade seemed to alter their behavior to cope with heat stress, as seen from the lack of physiological differences between treatments. The results indicate that providing cows with access to pasture under a temperate climate does not seem to have any detrimental physiological or production effects and providing them with shade can potentially decrease production costs and help with water conservation strategies as fewer cows were observed at the water when shade was provided.


Subject(s)
Cattle/physiology , Heat Stress Disorders/veterinary , Animals , Behavior, Animal/physiology , Body Temperature , Canada , Female , Heat Stress Disorders/prevention & control , Hot Temperature/adverse effects , Humidity , Lactation/physiology , Light , Water/physiology
7.
Tree Physiol ; 33(4): 438-45, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23574752

ABSTRACT

Herbivore effects on leaf litter can have a strong impact on ecosystem nutrient cycling. Although such effects are well described for insect herbivory, research on the impacts of browsing by mammalian herbivores on leaf litter dynamics and nutrient cycling has been more limited, particularly at the level of the individual plant. Clipping treatments (66% shoot removal twice, plus unclipped) were applied to analyse the effect of browsing on the phenology (start date and pattern of leaf shedding) and leaf litter quality (nitrogen (N), soluble sugars, starch and total non-structural carbohydrate concentrations, plus C : N ratios) of Betula pubescens Ehrh. and Quercus petraea [Matt.] Liebl. saplings. Clipping decreased leaf litter biomass and delayed leaf senescence and shedding, but did not change the phenological timing of litterfall between senescence and shedding. The quality of leaf litter of both species was increased by simulated browsing, through an increase in N and carbohydrate concentrations (mainly soluble sugars) and a decreased C : N ratio. This is the first evidence we are aware of that browsing may cause changes in leaf shedding phenology, delaying the process without altering its pattern. Our results also indicate that simulated browsing increases the quality of leaf litter. However, the potential positive effect of browsing on N cycling through litter quality may be offset by its negative impact on the amount of N shed per tree.


Subject(s)
Betula/physiology , Herbivory , Mammals/physiology , Quercus/physiology , Animals , Betula/growth & development , Ecosystem , Europe , Plant Leaves/growth & development , Plant Leaves/physiology , Quercus/growth & development , Random Allocation , Seasons , Trees/growth & development , Trees/physiology
8.
Plant Biol (Stuttg) ; 15(5): 798-807, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23173598

ABSTRACT

Whole-plant approaches allow quantification of the temporal overlap between primary and secondary growth. If the amount of time available to grow is short, there may be a high temporal overlap between shoot growth and wood formation. We hypothesise that such overlap depends on the duration of the growing season and relates to wood anatomy. We evaluated wood anatomy, shoot longitudinal and radial growth rates, fine root production and the concentrations of non-structural carbohydrates (NSC) in the wood of six sub-shrub species growing in sites with contrasting climatic conditions (Lepidium subulatum, Linum suffruticosum, Salvia lavandulifolia, Satureja montana, Ononis fruticosa, Echinospartum horridum). Sub-shrub species living in sites with a short growing season displayed a high overlap between aboveground primary and secondary growth and formed wide vessels, whereas species from the warmest and driest sites presented the reverse characteristics. The highest overlap was linked to a rapid shoot extension and thickening through the enhanced hydraulic conductivity provided by wide vessels. The reductions in NSC concentrations when growth peaked were low or moderate, indicating that sub-shrubs accumulate NSC in excess, as do trees. The temporal overlap among primary and secondary growth in woody plants may be connected to the duration and rates of shoot and wood growth, which in turn depend on the vessel lumen area.


Subject(s)
Magnoliopsida/growth & development , Plant Shoots/growth & development , Seasons , Wood/growth & development , Carbohydrate Metabolism , Flax/anatomy & histology , Flax/growth & development , Lepidium/anatomy & histology , Lepidium/growth & development , Magnoliopsida/anatomy & histology , Mediterranean Region , Plant Roots/growth & development , Salvia/anatomy & histology , Salvia/growth & development , Satureja/anatomy & histology , Satureja/growth & development , Wood/anatomy & histology
10.
J Environ Manage ; 104: 1-8, 2012 Aug 15.
Article in English | MEDLINE | ID: mdl-22484653

ABSTRACT

In this work, the performance of a photo-Fenton process-based textile effluent treatment was investigated using both solar and artificial light sources. A full 3(3) factorial experimental design was applied for the optimisation with respect to three parameters: initial pH, amounts of Fe(2+) (0.01-0.09 g L(-1)) and H(2)O(2) (1-7 g L(-1)). The photo-Fenton process response was evaluated on the basis of chemical oxygen demand (COD) removal and decolourisation. The optimum conditions of the photo-Fenton process were attained at concentration values of 0.05 g Fe(2+) L(-1) and 6.0 g H(2)O(2) L(-1) and pH 3, for both solar and artificial light sources. The effects of initial pH, and Fe(2+) and H(2)O(2) concentrations were evaluated. From the monitoring of TOC, COD, turbidity and decolourisation over time, the progress of the mineralisation of dyes was analysed, forming nitrate, ammonia nitrogen and nitrite. Low amounts of residual peroxide and iron, which were below the limit allowed by Brazilian environmental legislation, were attained after 360 min of irradiation time for both artificial and solar sources. An operational cost of US$ 6.85 per m(3) of treated effluent was estimated using solar irradiation.


Subject(s)
Industrial Waste , Photochemistry/methods , Textiles , Waste Disposal, Fluid/methods , Biological Oxygen Demand Analysis , Hydrogen Peroxide/chemistry , Iron/chemistry
11.
Water Sci Technol ; 63(7): 1506-12, 2011.
Article in English | MEDLINE | ID: mdl-21508557

ABSTRACT

The main objective of this study was to evaluate the metal content in water and sediment from the Toledo municipal lake, as well as the concentration levels of heavy metals in muscle and liver of four fish species. A digestion procedure was performed in all fish samples. Metal analysis was performed by using the Synchrotron Radiation X-ray Fluorescence technique. The accuracy and validity of the measurements were determined by analysis of certified reference materials. The highest Cr, Cu and Se concentration levels above the maximum tolerance limit according to the Brazilian norms in fish tissue could be associated with the metal uptake and accumulation due to the direct contact with contaminated water and sediment.


Subject(s)
Fishes/physiology , Fresh Water/analysis , Geologic Sediments/analysis , Metals/analysis , Water Pollutants, Chemical/analysis , Animals , Brazil , Liver/chemistry , Muscles/chemistry , Spectrometry, X-Ray Emission
12.
Tree Physiol ; 31(2): 150-9, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21388994

ABSTRACT

Current knowledge on tree carbon (C) allocation to wood is particularly scarce in plants subjected to disturbance factors, such as browsing, which affects forest regeneration worldwide and has an impact on the C balance of trees. Furthermore, quantifying the degree to which tree rings are formed from freshly assimilated vs. stored carbohydrates is highly relevant for our understanding of tree C allocation. We used (13)C labelling to quantify seasonal allocation of stored C to wood formation in two species with contrasting wood anatomy: Betula pubescens Ehrh. (diffuse-porous) and Quercus petraea [Matt.] Liebl. (ring-porous). Clipping treatments (66% shoot removal, and unclipped) were applied to analyse the effect of browsing on C allocation into tree rings, plus the effects on tree growth, architecture, ring width and non-structural carbohydrates (NSCs). The relative contribution of stored C to wood formation was greater in the ring-porous (55-70%) than in the diffuse-porous species (35-60%), although each species followed different seasonal trends. Clipping did not cause a significant depletion of C stores in either species. Nonetheless, a significant increase in the proportion of stored C allocated to earlywood growth was observed in clipped birches, and this could be explained through changes in tree architecture after clipping. The size of C pools across tree species seems to be important in determining the variability of seasonal C allocation patterns to wood and their sensibility to disturbances such as browsing. Our results indicate that the observed changes in C allocation to earlywood in birch were not related to variations in the amount or concentration of NSC stores, but to changes in the seasonal availability of recently assimilated C caused by modifications in tree architecture after browsing.


Subject(s)
Betula/anatomy & histology , Betula/growth & development , Quercus/anatomy & histology , Quercus/growth & development , Betula/metabolism , Carbohydrate Metabolism , Feeding Behavior , Plant Stems/anatomy & histology , Plant Stems/chemistry , Plant Stems/growth & development , Plant Stems/metabolism , Quercus/metabolism , Seasons
13.
Appl Radiat Isot ; 68(12): 2202-7, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20828660

ABSTRACT

This study is focused on the analysis of an accumulation of inorganic elements in muscles, liver and gonad of seven fish species from São Francisco River located in the Paraná state of Brazil. Concentrations of the elements were determined using the SR-TXRF technique. In the muscles of fish species, negative length dependent relationships were observed for chromium and zinc ion absorption. The obtained results showed that accumulated Cr ions values are above the limits defined in the Brazilian legislative norm on food.


Subject(s)
Fishes/metabolism , Gonads/metabolism , Liver/metabolism , Muscles/metabolism , Trace Elements/metabolism , Animals , Brazil , Species Specificity
14.
Bull Environ Contam Toxicol ; 82(6): 767-71, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19280093

ABSTRACT

The effect of Cr(6+) on Allium cepa root length was studied using both clean and polluted river waters. Seven series of Cr(6+)-doped polluted and non-polluted river waters were used to grow onions. Chromium concentration (Cr(6+)) of 4.2 mg L(-1)(EC(50) value), doped in clean river water caused a 50% reduction of root length, while in organically polluted samples similar root growth inhibition occurred at 12.0 mg Cr(6+) L(-1). The results suggested that there was a dislocation to higher values in toxic chromium concentration in polluted river water due to the eutrophization level of river water.


Subject(s)
Chromium/toxicity , Onions/drug effects , Plant Roots/drug effects , Rivers/chemistry , Water Pollution , Chromium/pharmacology , Dose-Response Relationship, Drug , Onions/growth & development , Plant Roots/growth & development , Toxicity Tests/methods
15.
Tree Physiol ; 27(7): 951-60, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17403647

ABSTRACT

Leaf exchange is an abrupt phenological event that drastically modifies the morphology and physiology of the aerial portion of the plant. We examined if water and osmolyte differences between old leaves and new organs trigger leaf exchange, and whether the differences are closely linked to the resource resorption process in senescing leaves. We monitored concentrations of osmolyte, water, non-structural carbohydrate, nitrogen and potassium in senescing leaves and in emerging new leaves and inflorescences of a Mediterranean leaf exchanger (Cistus laurifolius L.) growing in NE Spain. Old leaves rehydrated markedly during most of the senescence process, which co-occurred with the extension of new shoots, suggesting the lack of a clear-cut switch in water supply from old to new organs. The accumulation of osmolytes in the early stage of leaf senescence might account for this rehydration. Osmolyte dynamics in old leaves depended largely on the progression of resource resorption from senescing organs but were mostly unrelated to water content during late senescence. We conclude that dehydration of old leaves is not a prerequisite for the triggering of leaf exchange. The finding that most nutrients and carbohydrates accumulated in new organs before senescing leaves massively exported resources, and the absence of relevant differences between the dynamics of old leaves at the base of inflorescences and those at the base of vegetative shoots, indicate that the nutrient and carbohydrate demands of new organs do not trigger leaf exchange.


Subject(s)
Carbon/metabolism , Cistus/metabolism , Plant Leaves/metabolism , Water/metabolism , Biomass , Carbohydrates , Cistus/growth & development , Mediterranean Region , Models, Biological , Nitrogen/metabolism , Osmotic Pressure , Plant Leaves/growth & development , Seasons
16.
Plant Biol (Stuttg) ; 9(1): 49-58, 2007 Jan.
Article in English | MEDLINE | ID: mdl-16883482

ABSTRACT

Previous studies have led to contrasting results about the role of overwintering leaves as storage sites, which is related to leaf longevity and life-form. The aim of this study was to evaluate the functional role of the leaves of four species of Mediterranean sub-shrubs, with different leaf phenology, as sources of nitrogen (N) and non-structural carbohydrates (NSC) for shoot growth. The seasonal dynamics of the concentrations and pools of N and NSC were assessed monthly in the leaves and woody organs of each species. Overwintering and spring leaves served as N and NSC sources for shoot growth in the evergreen species analyzed, providing up to 73 % and 324 % of the N demand for spring and autumn growth, respectively. Excess autumn N was stored in woody structures which contributed to the N and NSC requirements of spring growth. In the winter deciduous species, woody organs were the main N source for spring growth, while current photosynthesis from immature brachyblasts seemed to be the main carbon (C) source. Due to their short lifespan, overwintering and spring leaves did not show several translocation processes throughout their life time, their contribution to new growth being made during senescence. The successive exchange of leaf cohorts displayed by Mediterranean sub-shrubs might serve as a mechanism to recycle N and C between consecutive cohorts as plants perform the pheno-morphological changes needed to adapt their morphology to the seasonality of their environment.


Subject(s)
Carbohydrate Metabolism , Fabaceae/metabolism , Nitrogen/metabolism , Salvia/metabolism , Satureja/metabolism , Fabaceae/growth & development , Fabaceae/physiology , Mediterranean Region , Plant Leaves/metabolism , Plant Leaves/physiology , Plant Shoots/growth & development , Plant Shoots/physiology , Salvia/growth & development , Salvia/physiology , Satureja/growth & development , Satureja/physiology , Seasons
17.
Rev. neurol. (Ed. impr.) ; 43(5): 263-267, 1 sept., 2006. ilus, graf
Article in Es | IBECS | ID: ibc-049430

ABSTRACT

Introducción. La cefalea crónica diaria (CCD) es un cuadrodoloroso crónico frecuente en la práctica neurológica. El diagnósticoes clínico y el abordaje terapéutico resulta complejo. No estáclaro todavía cuál es su mecanismo de producción, pero se reconoceun componente genético como factor predisponente. Son múltipleslas áreas que participan en la generación de cefaleas primarias,entre las que se encuentra la sustancia gris periacueductal (SGPA),que participa como neuromoduladora tanto en cefaleas como enotros cuadros dolorosos crónicos. Objetivos. Para evaluar posiblescambios bioquímicos en pacientes con CCD se estudiaron los espectrospor resonancia magnética en la SGPA. Sujetos y métodos. Seestudiaron los espectros en la SGPA en 17 pacientes con CCD y secompararon con el espectro promedio de 17 sujetos sanos a travésdel análisis espectroscópico diferencial. Resultados. Los sujetos conCCD presentan una reducción mayor del 70% del metabolito N-acetilaspartato glutamato (NAAG) en la SGPA. El NAAG es un péptidorelacionado con actividad antinociceptiva. Conclusión. La reduccióndel NAAG en la SPGA sugiere una alteración de la neuromodulaciónde sistemas antinociceptivos en sujetos con CCD. Queda pendientede que se establezca si la CCD es la causa o la consecuencia


Introduction. Chronic daily headache (CDH) is a chronic painful clinical condition that is frequently found inneurological practice. Diagnosis is clinical and the therapeutic approach is complex. Its mechanism of production is still notaltogether clear, but a genetic component is acknowledged as a predisposing factor. Numerous areas are involved in thegeneration of primary headaches, including the periaqueductal grey matter (PAGM), which plays a role as a neuromodulatorboth in headaches and in other chronic painful conditions. Aims. In order to evaluate possible biochemical changes inpatients with CDH, magnetic resonance imaging was used to study the spectra produced in the PAGM. Subjects and methods.The spectra in the PAGM were studied in 17 patients with CDH. These were compared with the average spectra in 17 healthysubjects by means of differential spectroscopy. Results. Subjects with CDH show a reduction of over 70% in the level of themetabolite N-acetyl-aspartyl-glutamate (NAAG) in the PAGM. NAAG is a peptide involved in antinociceptive activity. Conclusions.The reduction of NAAG in the PAGM suggests altered neuromodulation of the antinociceptive systems in subjects with CDH.Whether CDH is the cause or the consequence has still to be determined


Subject(s)
Male , Female , Humans , Headache/physiopathology , Control Groups , Magnetic Resonance Spectroscopy , Periaqueductal Gray/physiology , Migraine Disorders
18.
Rev Neurol ; 43(5): 263-7, 2006.
Article in Spanish | MEDLINE | ID: mdl-16941423

ABSTRACT

INTRODUCTION: Chronic daily headache (CDH) is a chronic painful clinical condition that is frequently found in neurological practice. Diagnosis is clinical and the therapeutic approach is complex. Its mechanism of production is still not altogether clear, but a genetic component is acknowledged as a predisposing factor. Numerous areas are involved in the generation of primary headaches, including the periaqueductal grey matter (PAGM), which plays a role as a neuromodulator both in headaches and in other chronic painful conditions. AIMS: In order to evaluate possible biochemical changes in patients with CDH, magnetic resonance imaging was used to study the spectra produced in the PAGM. SUBJECTS AND METHODS: The spectra in the PAGM were studied in 17 patients with CDH. These were compared with the average spectra in 17 healthy subjects by means of differential spectroscopy. RESULTS: Subjects with CDH show a reduction of over 70% in the level of the metabolite N-acetyl-aspartyl-glutamate (NAAG) in the PAGM. NAAG is a peptide involved in antinociceptive activity. CONCLUSIONS: The reduction of NAAG in the PAGM suggests altered neuromodulation of the antinociceptive systems in subjects with CDH. Whether CDH is the cause or the consequence has still to be determined.


Subject(s)
Headache Disorders/physiopathology , Pain/physiopathology , Periaqueductal Gray/metabolism , Adult , Dipeptides/metabolism , Female , Headache Disorders/metabolism , Headache Disorders/pathology , Humans , Magnetic Resonance Imaging , Middle Aged , Neuroprotective Agents/metabolism , Periaqueductal Gray/anatomy & histology , Periaqueductal Gray/pathology
19.
Bone ; 32(4): 372-80, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12689680

ABSTRACT

During our survey of herbs looking for activity on bone metabolism, we found that the dried leaves of sage strongly inhibit bone resorption. Therefore, we investigated several common herbs rich in essential oils (sage, rosemary, and thyme) and essential oils extracted from these herbs and other plants (oils of sage, rosemary, juniper, pine, dwarf pine, turpentine, and eucalyptus) as well as their monoterpene components (thujone, eucalyptol, camphor, borneol, thymol, alpha-pinene, beta-pinene, bornylacetate as well as menthol) and found that they inhibit bone resorption when added to the food of rats. Pine oil, used as a representative essential oil, protects an osteoporosis model, the aged ovariectomized rat, from bone loss. The monoterpenes borneol, thymol, and camphor are directly inhibitory in the osteoclast resorption pit assay. Nonpolar monoterpenes may require metabolism to be active in vitro, for example, cis-verbenol, a metabolite of alpha-pinene occurring in human urine, inhibits osteoclast activity in contrast to the parent compound. Within 30 min borneol inhibits the formation of actin rings, a characteristic of resorbing osteoclasts indicating cell polarization. Both the in vitro and the in vivo effects of borneol are reversible. Our study demonstrates for the first time that essential oils and monoterpenes are efficient inhibitors of bone resorption in the rat.


Subject(s)
Bone Resorption/diet therapy , Monoterpenes/pharmacology , Oils, Volatile/pharmacology , Osteoporosis/diet therapy , Plants, Medicinal , Animals , Animals, Newborn , Bone Density/drug effects , Cells, Cultured , Female , Male , Monoterpenes/administration & dosage , Oils, Volatile/administration & dosage , Osteoclasts/drug effects , Rats , Time Factors
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