978 resultados para hair-plot


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Dans «La Belle au bois dormant» et «Dornröschen», des personnages aux pouvoirs magiques déterminent l'avenir des héroïnes en leur accordant des dons positifs ou négatifs. La comparaison des textes montre toutefois que les fées et les weise Frauen (femmes sages), issues de traditions différentes, ne jouent pas les mêmes rôles dans les intrigues et que leurs actions ne sont pas présentées de la même manière. Si le conte de Perrault explique les motivations des fées et en fait des êtres réfléchis, le Märchen des Grimm représente les weise Frauen comme des figures énigmatiques appartenant à un univers où se déroulent des événements inexpliqués. Ainsi, le traitement de ces personnages féminins emblématiques reflète une volonté de rationaliser le merveilleux chez Perrault, contrairement aux Grimm, et témoigne ainsi de différences génériques, mais aussi historiques et culturelles plus larges. / Both in «La Belle au bois dormant» and in «Dornröschen», characters with magical powers determine the future of the heroines by endowing them with positive or negative gifts. The comparison of the two texts nonetheless shows that the fées (fairies) and the weise Frauen (wise women) -coming as they do from different cultural traditions- do not play the same role in the plot, nor are their actions presented in the same way. Whereas Perrault's conte explains the fairies' motivations and portrays them as rational beings, Grimm's Märchen depicts weise Frauen as mysterious women who belong to a universe of unexplained events. The treatment of these wondrous feminine figures thus testifies to a willingness to rationalise the marvellous in Perrault, and to present it as self-evident in Grimm, thereby reflecting generic as well as broader historical and cultural differences.

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Mutations in the epithelial morphogen ectodysplasin-A (EDA), a member of the tumor necrosis factor (TNF) family, are responsible for the human disorder X-linked hypohidrotic ectodermal dysplasia (XLHED) characterized by impaired development of hair, eccrine sweat glands, and teeth. EDA-A1 and EDA-A2 are two splice variants of EDA, which bind distinct EDA-A1 and X-linked EDA-A2 receptors. We identified a series of novel EDA mutations in families with XLHED, allowing the identification of the following three functionally important regions in EDA: a C-terminal TNF homology domain, a collagen domain, and a furin protease recognition sequence. Mutations in the TNF homology domain impair binding of both splice variants to their receptors. Mutations in the collagen domain can inhibit multimerization of the TNF homology region, whereas those in the consensus furin recognition sequence prevent proteolytic cleavage of EDA. Finally, a mutation affecting an intron splice donor site is predicted to eliminate specifically the EDA-A1 but not the EDA-A2 splice variant. Thus a proteolytically processed, oligomeric form of EDA-A1 is required in vivo for proper morphogenesis.

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Acute organophosphate (OP) intoxication is associated with many symptoms and clinical signs, including potentially life-threatening seizures and status epilepticus. Instead of being linked to the direct cholinergic toxidrome, OP-related seizures are more probably linked to the interaction of OPs with acetylcholineindependent neuromodulation pathways, such as GABA and NMDA. The importance of preventing, or recognizing and treating OP-related seizures lies in that, the central nervous system (CNS) damage from OP poisoning is thought to be due to the excitotoxicity of the seizure activity itself rather than a direct toxic effect. Muscular weakness and paralysis occurring 1-4 days after the resolution of an acute cholinergic toxidrome, the intermediate syndrome is usually not diagnosed until significant respiratory insufficiency has occurred; it is nevertheless a major cause of OP-induced morbidity and mortality and requires aggressive supportive treatment. The condition usually resolves spontaneously in 1-2 weeks.Treatment of OP intoxication relies on prompt diagnosis, and specific and immediate treatment of the lifethreatening symptoms. Since patients suffering from OP poisoning can secondarily expose care providers via contaminated skin, clothing, hair, or body fluids. EMS and hospital caregivers should be prepared to protect themselves with appropriate protective equipment, isolate such patients, and decontaminate them. After prompt decontamination, the initial priority of patient management is an immediate ABCDE (A : airway, B : breathing, C : circulation, D : dysfunction or disability of the central nervous system, and E : exposure) resuscitation approach, including aggressive respiratory support, since respiratory failure is the usual ultimate cause of death. The subsequent priority is initiating atropine therapy to oppose the muscarinic symptoms and diazepam to prevent or control seizures, with oximes added to enhance acetylcholinesterase (AChE) activity recovery. Large doses of atropine and oximes may be necessary for poisoning due to suicidal ingestions of OP pesticides.

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Dermatophytes are highly specialized filamentous fungi which cause the majority of superficial mycoses in humans and animals. The high secreted proteolytic activity of these microorganisms during growth on proteins is assumed to be linked to their particular ability to exclusively infect keratinized host structures such as the skin stratum corneum, hair, and nails. Individual secreted dermatophyte proteases were recently described and linked with the in vitro digestion of keratin. However, the overall adaptation and transcriptional response of dermatophytes during protein degradation are largely unknown. To address this question, we constructed a cDNA microarray for the human pathogenic dermatophyte Trichophyton rubrum that was based on transcripts of the fungus grown on proteins. Profiles of gene expression during the growth of T. rubrum on soy and keratin protein displayed the activation of a large set of genes that encode secreted endo- and exoproteases. In addition, other specifically induced factors potentially implicated in protein utilization were identified, including heat shock proteins, transporters, metabolic enzymes, transcription factors, and hypothetical proteins with unknown functions. Of particular interest is the strong upregulation of key enzymes of the glyoxylate cycle in T. rubrum during growth on soy and keratin, namely, isocitrate lyase and malate synthase. This broad-scale transcriptional analysis of dermatophytes during growth on proteins reveals new putative pathogenicity-related host adaptation mechanisms of these human pathogenic fungi.

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The terminal segment of the intermediate hair in the semi-aquatic Chirmarrogale hantu and Bectigale elegans is investigated with a view to a taxonomic interpretation. Nectogale is characterized by especially fine hairs which strongly contrast with the distally thickened hairs of Chimarrogale. In spite of these differences, the hairs of both genera are characterized by a H-shaped profile. According to Vogel & Köpchen (1977), this criterion confirms the discussed membership to the Soricinae.

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The peroxisome proliferator-activated receptors (PPAR) are ligand-activated transcription factors that belong to the nuclear hormone receptor family. Three isotypes (PPAR alpha, PPAR beta or delta, and PPAR gamma) with distinct tissue distributions and cellular functions have been found in vertebrates. All three PPAR isotypes are expressed in rodent and human skin. They were initially investigated for a possible function in the establishment of the permeability barrier in skin because of their known function in lipid metabolism in other cell types. In vitro studies using specific PPAR agonists and in vivo gene disruption approaches in mice indeed suggest an important contribution of PPAR alpha in the formation of the epidermal barrier and in sebocyte differentiation. The PPAR gamma isotype plays a role in stimulating sebocyte development and lipogenesis, but does not appear to contribute to epidermal tissue differentiation. The third isotype, PPAR beta, regulates the late stages of sebaceous cell differentiation, and is the most effective isotype in stimulating lipid production in these cells, both in rodents and in humans. In addition, PPAR beta activation has pro-differentiating effects in keratinocytes under normal and inflammatory conditions. Finally, preliminary studies also point to a potential role of PPAR in hair follicle growth and in melanocyte differentiation. By their diverse biological effects on cell proliferation and differentiation in the skin, PPAR agonists or antagonists may offer interesting opportunities for the treatment of various skin disorders characterized by inflammation, cell hyperproliferation, and aberrant differentiation.

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Dryland agriculture in Cabo Verde copes with steep slopes, inadequate practices, irregular intense rain, recurrent droughts, high runoff rates, severe soil erosion and declining fertility, leading to the inefficient use of rainwater. Maize and beans occupy N80% of the arable land in low-input, low-yielding subsistence farming. Three collaborative field trialswere conducted in different agroecological zones to evaluate the effects ofwater-conservation techniques (mulching of crop residue, a soil surfactant and pigeon-pea hedges) combinedwith organic amendments (compost and animal or green manure) on runoff and soil loss. During the 2011 and 2012 rainy seasons, three treatments and one control (traditional practice) were applied to 44- and 24-m2 field plots. A local maize variety and two types of beanswere planted. Runoff and suspended sedimentswere collected and quantified after each daily erosive rainfall. Runoff occurred for rainfalls≥50mm(slope b10%, loamy Kastanozem),≥60mm(slope≤23%, silt–clay–loam Regosol) and≥40mm(slope≤37%, sandy loam Cambisol). Runoffwas significantly reduced only with themulch treatment on the slope N10% and in the treatment of surfactant with organic amendment on the slope b10%. Soil loss reached 16.6, 5.1, 6.6 and 0.4 Mg ha−1 on the Regosol (≤23% slope) for the control, surfactant, pigeon-pea and mulch/pigeon-pea (with organic amendment) treatments, respectively; 3.2, 0.9, 1.3 and 0.1 Mg ha−1 on the Cambisol (≤37% slope) and b0. 2Mg ha−1 for all treatments and control on the Kastanozem(b10% slope). Erosion was highly positively correlated with runoff. Mulch with pigeon-pea combinedwith an organic amendment significantly reduced runoff and erosion fromagricultural fields on steep slopes, contributing to improved use of rainwater at the plot level. Sustainable land management techniques, such as mulching with pigeon-pea hedges and an organic amendment, should be advocated and promoted for the semiarid hillsides of Cabo Verde prone to erosion to increase rainwater-use and to prevent further soil degradation.

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Introduction: To determine the metabolic effect of teriparatide (TPTD) on bone, 99mTc-MDP skeletal plasma clearance was measured in postmenopausal women with osteoporosis treated with TPTD 20 μg/day. Methods: Ten postmenopausal women with osteoporosis had radionuclide bone scans at baseline, 3, and 18 months after starting TPTD 20 μg/day and after 6 months off therapy. Participants were injected with 600 MBq 99mTc- MDP and whole body bone scans acquired at 10 min, 1, 2, 3, and 4 h. Multiple blood samples were taken between 5 min and 4 h and free 99mTc-MDP measured using ultrafiltration. 99mTc-MDP plasma clearance (Kbone) was evaluated using the Patlak plot method. Regional differences in Kbone were studied by measuring the whole skeleton and subregions. Serum procollagen type I Nterminal propeptide (PINP), bone-specific alkaline phosphatase (BSAP), and urinary N-terminal telopeptide (NTX) were measured at each visit.Discussion: The median increase from baseline in whole skeleton Kbone was 22% (P=0.004) at 3 months and 34% (P= 0.002) at 18 months, decreasing to 0.7% after 6 months off therapy. In subregions, Kbone value increases were statistically significant at 3 months and in all subregions except the pelvis at 18 months. After 6 months off therapy, subregional Kbone values also returned toward baseline. Bone markers increases from baseline were statistically significant at 3 and 18 months (BSAP, 15% and 36%; PINP, 137% and 192%; NTX, 109% and 125%). After 6 months off therapy, PINP and NTX values had declined, though remained above baseline (BSAP, −3%; PINP, 43%; NTX, 56%). Increased Kbone values in the whole body and lower extremities were correlated with increases in most bone markers at 3 and 18 months. Increased skeletal uptake of 99mTc-MDP during treatment with TPTD is indicative of increased bone formation and is supported by increases in bone turnover markers.Conclusion: Changes in Kbone and skeletal uptake measured by radionuclide bone scans in patients taking TPTD are the result of metabolic activity of the drug. These data may provide physicians with useful insights when interpreting bone scan results in this population.

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Albitization is a common process during which hydrothermal fluids convert plagioclase and/or K-feldspar into nearly pure albite; however, its specific mechanism in granitoids is not well understood. The c. 1700 Ma A-type metaluminous ferroan granites in the Khetri complex of Rajasthan, NW India, have been albitized to a large extent by two metasomatic fronts, an initial transformation of oligoclase to nearly pure albite and a subsequent replacement of microcline by albite, with sharp contacts between the microcline-bearing and microcline-free zones. Albitization has bleached the original pinkish grey granite and turned it white. The mineralogical changes include transformation of oligoclase (similar to An(12)) and microcline (similar to Or(95)) to almost pure albite (similar to An(0 center dot 5-2)), amphibole from potassian ferropargasite (X-Fe 0 center dot 84-0 center dot 86) to potassic hastingsite (X-Fe 0 center dot 88-0 center dot 97) and actinolite (X-Fe 0 center dot 32-0 center dot 67), and biotite from annite (X-Fe 0 center dot 71-0 center dot 74) to annite (X-Fe 0 center dot 90-0 center dot 91). Whole-rock isocon diagrams show that, during albitization, the granites experienced major hydration, slight gain in Si and major gain in Na, whereas K, Mg, Fe and Ca were lost along with Rb, Ba, Sr, Zn, light rare earth elements and U. Whole-rock Sm-Nd isotope data plot on an apparent isochron of 1419 +/- 98 Ma and reveal significant disturbance and at least partial resetting of the intrusion age. Severe scatter in the whole-rock Rb-Sr isochron plot reflects the extreme Rb loss in the completely albitized samples, effectively freezing Sr-87/Sr-86 ratios in the albite granites at very high values (0 center dot 725-0 center dot 735). This indicates either infiltration of highly radiogenic Sr from the country rock or, more likely, radiogenic ingrowth during a considerable time lag (estimated to be at least 300 Myr) between original intrusion and albitization. The albitization took place at similar to 350-400 degrees C. It was caused by the infiltration of an ascending hydrothermal fluid that had acquired high Na/K and Na/Ca ratios during migration through metamorphic rocks at even lower temperatures in the periphery of the plutons. Oxygen isotope ratios increase from delta O-18 = 7 parts per thousand in the original granite to values of 9-10 parts per thousand in completely albitized samples, suggesting that the fluid had equilibrated with surrounding metamorphosed crust. A metasomatic model, using chromatographic theory of fluid infiltration, explains the process for generating the observed zonation in terms of a leading metasomatic front where oligoclase of the original granite is converted to albite, and a second, trailing front where microcline is also converted to albite. The temperature gradients driving the fluid infiltration may have been produced by the high heat production of the granites themselves. The confinement of the albitized granites along the NE-SW-trending Khetri lineament and the pervasive nature of the albitization suggest that the albitizing fluids possibly originated during reactivation of the lineament. More generally, steady-state temperature gradients induced by the high internal heat production of A-type granites may provide the driving force for similar metasomatic and ore-forming processes in other highly enriched granitoid bodies.

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Increase in potency of adult stem/progenitor cells holds great expectations for regenerative medicine; reprogramming is achieved by manipulating the genome or indirectly by manipulating the microenvironment. However, the genetic approach, which can result in lineage conversion up to ground pluripotent embryonic state, will certainly face strict regulatory constraints and consequently translation to the clinic may be difficult. Manipulating stem cell fate without altering the genome of adult stem cells is a promising alternative. My laboratory has demonstrated that non hairy squamous epithelia e.g. the cornea, the oral cavity, the oesophagus, the vagina, contain clonogenic stem cells that can respond to skin morphogenetic signals and form epidermis, cycling hair follicles and sebaceous glands. This capacity is maintained in serial transplantation, crosses primary germ line boundaries and is intrinsic to the stem cells, as cells which have never been exposed to cell culture behave in a similar fashion. Even more surprising, the thymus contains a population of clonogenic epithelial cells of endodermal origin that maintain a thymic identity in culture and have the capacity to incorporate into a thymic network, but can acquire the functionality of bona fide multipotent stem cells of the skin when exposed to proper developmental signals. Thymic epithelial cells exposed to a skin microenvironment exhibit a down-regulation or silencing of transcription factors important for thymic function. Hence, it is possible to reveal unsuspected potency and even to robustly reprogram stem cells by solely manipulating the microenvironment.

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BACKGROUND: The only known albino gorilla, named Snowflake, was a male wild born individual from Equatorial Guinea who lived at the Barcelona Zoo for almost 40 years. He was diagnosed with non-syndromic oculocutaneous albinism, i.e. white hair, light eyes, pink skin, photophobia and reduced visual acuity. Despite previous efforts to explain the genetic cause, this is still unknown. Here, we study the genetic cause of his albinism and making use of whole genome sequencing data we find a higher inbreeding coefficient compared to other gorillas.RESULTS: We successfully identified the causal genetic variant for Snowflake's albinism, a non-synonymous single nucleotide variant located in a transmembrane region of SLC45A2. This transporter is known to be involved in oculocutaneous albinism type 4 (OCA4) in humans. We provide experimental evidence that shows that this amino acid replacement alters the membrane spanning capability of this transmembrane region. Finally, we provide a comprehensive study of genome-wide patterns of autozygogosity revealing that Snowflake's parents were related, being this the first report of inbreeding in a wild born Western lowland gorilla.CONCLUSIONS: In this study we demonstrate how the use of whole genome sequencing can be extended to link genotype and phenotype in non-model organisms and it can be a powerful tool in conservation genetics (e.g., inbreeding and genetic diversity) with the expected decrease in sequencing cost.

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The treatments for ischemic stroke can only be administered in a narrow time-window. However, the ischemia onset time is unknown in ~30% of stroke patients (wake-up strokes). The objective of this study was to determine whether MR spectra of ischemic brains might allow the precise estimation of cerebral ischemia onset time. We modeled ischemic stroke in male ICR-CD1 mice using a permanent middle cerebral artery filament occlusion model with laser Doppler control of the regional cerebral blood flow. Mice were then subjected to repeated MRS measurements of ipsilateral striatum at 14.1 T. A striking initial increase in γ-aminobutyric acid (GABA) and no increase in glutamine were observed. A steady decline was observed for taurine (Tau), N-acetyl-aspartate (NAA) and similarly for the sum of NAA+Tau+glutamate that mimicked an exponential function. The estimation of the time of onset of permanent ischemia within 6 hours in a blinded experiment with mice showed an accuracy of 33±10 minutes. A plot of GABA, Tau, and neuronal marker concentrations against the ratio of acetate/NAA allowed precise separation of mice whose ischemia onset lay within arbitrarily chosen time-windows. We conclude that (1)H-MRS has the potential to detect the clinically relevant time of onset of ischemic stroke.

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Male bees of the tribe Euglossini collect volatile chemicals secreted by orchids using dense patches of hair on the front tarsi. After collecting chemicals, the bee hovers while transferring these fragrances to invaginations on the hind tibiae. The fragrance collection and hovering behaviours are repeated multiple times. Here I report preliminary field observations on the length of fragrance collection and hovering phases in bees of the Eulaema meriana (Oliver, 1789) mimicry complex visiting the orchid Catasetum discolor in Kavanayén,Venezuela. I observed that in extended visits with many cycles of fragrance collection and hovering, the length of each collection phase gradually increased, while the length of hovering phase was static. This suggests either that chemicals secreted by orchids are in limited supply or that efficiency of fragrance collection drops.

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Late Triassic submarine alkali basalts and hawaiites were collected from two superimposed tectonic slices belonging to the Kara Dere - Sayrun unit of the Middle Antalya nappes, southwestern Turkey. New determinations on conodont faunas allow to date this sequence to the Lower Carnian (Julian). The volcanic rocks show rather homogeneous compositions, with high TiO2 and relatively low MgO and Ni contents which suggest olivine fractionation. Their primitive mantle-normalised multi-elements plots show Nb and Ta enrichments relative to La, Pb negative anomalies and heavy rare earth element and Y depletions typical of intraplate ocean island basalts. These characteristics are consistent with the major and trace element compositions of their primary clinopyroxene phenocrysts, which do not show any feature ascribable to crustal contamination. The studied lavas display a restricted range of epsilon Nd (+4.6 to +5.2) which falls within the range of ocean island basalts. Their initial (Nd-143/Nd-144)i ratios are too low to be explained by a simple mixing line between depleted MORB mantle (DMM) and HIMU components. Their Pb and Nd isotopic compositions plot along a mixing line between HIMU component and an enriched mantle, the composition of which could be the result of the addition of about 5 to 8% of an EM2 component (recycled marine sediments) to DMM. The lack of evidence for any continental crustal component. in their genesis could be consistent with their emplacement in an intra-oceanic setting.

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The structure of the shield of curly overhairs was studied in 22 genera of shrews, using scanning electron microscopy. The cross section of the shield is quadriconcave with two sides showing particular scale patterns or a relief which can be grouped into 4 morphological types: 1) a smooth type with, at most, shallow U-shaped notches; 2) a type with uniserial, V-shaped tiled notches; 3) a type with a groove and irregular notches; 4) a type with a deep ridged groove. Myosorex, which occupies a basal phyletic position, shows type 3. This type is therefore interpreted as an ancestral character state. It is found also in Feroculus and in some Sylvisorex. In the Crocidurinae, this type evolved into type 2 (Scutisorex and some Indomalayan Crocidura), and finally into type 1 (Suncus and most Crocidura). In the Soricinae, it evolved into type 4, which is common to all genera except Megasorex and Notiosorex. These two genera possess type 1 which is interpreted as being a synapomorphous character of these genera. The regression of the complex structure under dry climatic conditions supports the hypothesis that the function of the grooved form of hair is water repulsion.