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1.
Theor Appl Genet ; 137(1): 29, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38261028

RESUMEN

KEY MESSAGE: Inversions and translocations are the major chromosomal rearrangements involved in Vigna subgenera evolution, being Vigna vexillata the most divergent species. Centromeric repositioning seems to be frequent within the genus. Oligonucleotide-based fluorescence in situ hybridization (Oligo-FISH) provides a powerful chromosome identification system for inferring plant chromosomal evolution. Aiming to understand macrosynteny, chromosomal diversity, and the evolution of bean species from five Vigna subgenera, we constructed cytogenetic maps for eight taxa using oligo-FISH-based chromosome identification. We used oligopainting probes from chromosomes 2 and 3 of Phaseolus vulgaris L. and two barcode probes designed from V. unguiculata (L.) Walp. genome. Additionally, we analyzed genomic blocks among the Ancestral Phaseoleae Karyotype (APK), two V. unguiculata subspecies (V. subg. Vigna), and V. angularis (Willd.) Ohwi & Ohashi (V. subg. Ceratotropis). We observed macrosynteny for chromosomes 2, 3, 4, 6, 7, 8, 9, and 10 in all investigated taxa except for V. vexillata (L.) A. Rich (V. subg. Plectrotropis), in which only chromosomes 4, 7, and 9 were unambiguously identified. Collinearity breaks involved with chromosomes 2 and 3 were revealed. We identified minor differences in the painting pattern among the subgenera, in addition to multiple intra- and interblock inversions and intrachromosomal translocations. Other rearrangements included a pericentric inversion in chromosome 4 (V. subg. Vigna), a reciprocal translocation between chromosomes 1 and 5 (V. subg. Ceratotropis), a potential deletion in chromosome 11 of V. radiata (L.) Wilczek, as well as multiple intrablock inversions and centromere repositioning via genomic blocks. Our study allowed the visualization of karyotypic patterns in each subgenus, revealing important information for understanding intrageneric karyotypic evolution, and suggesting V. vexillata as the most karyotypically divergent species.


Asunto(s)
Phaseolus , Vigna , Vigna/genética , Hibridación Fluorescente in Situ , Translocación Genética , Reordenamiento Génico , Phaseolus/genética
2.
Int J Mol Sci ; 24(24)2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38139046

RESUMEN

Cognitive abilities tend to decline with aging, with variation between individuals, and many studies seek to identify genetic biomarkers that more accurately anticipate risks related to pathological aging. We investigated the influence of BDNF, NTRK2, and FNDC5 single nucleotide polymorphisms (SNPs) on the cognitive performance of young and older adults with contrasting educational backgrounds. We addressed three questions: (1) Is education associated with reduced age-related cognitive decline? (2) Does the presence of SNPs explain the variation in cognitive performance observed late in life? (3) Is education differentially associated with cognition based on the presence of BDNF, NTRK2, or FNDC5 polymorphisms? We measured the cognitive functions of young and older participants, with lower and higher education, using specific and sensitive tests of the Cambridge Automated Neuropsychological Test Assessment Battery. A three-way ANOVA revealed that SNPs were associated with differential performances in executive functions, episodic memory, sustained attention, mental and motor response speed, and visual recognition memory and that higher educational levels improved the affected cognitive functions. The results revealed that distinct SNPs affect cognition late in life differentially, suggesting their utility as potential biomarkers and emphasizing the importance of cognitive stimulation that advanced education early in life provides.


Asunto(s)
Disfunción Cognitiva , Memoria Episódica , Humanos , Anciano , Factor Neurotrófico Derivado del Encéfalo/genética , Disfunción Cognitiva/genética , Cognición/fisiología , Polimorfismo de Nucleótido Simple , Fibronectinas/genética , Biomarcadores , Pruebas Neuropsicológicas
3.
Biol Pharm Bull ; 45(3): 245-249, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35228391

RESUMEN

Inflammation is part of the pathophysiology of diabetic nephropathy (DN), and mast cells (MCs) appear to increase in number within the kidney of humans and animals with diabetes. Disodium cromoglycate (CG) not only inhibits the degranulation of MCs but also has several secondary effects that may improve inflammation. However, little is known about the effects of CG treatment on kidney collagen deposition and myofibroblast population in animals with type I diabetes (DM1). Data presented here suggest that the increases in the density and activity of MCs within the kidney in the early stages of DN contribute to tubulointerstitial collagen deposition, even in the absence of alterations in the renal myofibroblast population. Moreover, CG treatment showed renoprotective effects in rats with DM1, which appear to be linked to its mast cell stabilizing property and its ability to avoid some detrimental morphofunctional alterations.


Asunto(s)
Diabetes Mellitus Tipo 1 , Nefropatías Diabéticas , Animales , Colágeno , Cromolin Sódico/farmacología , Cromolin Sódico/uso terapéutico , Nefropatías Diabéticas/tratamiento farmacológico , Riñón , Ratas
4.
Sensors (Basel) ; 19(14)2019 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-31331071

RESUMEN

Internet of Things (IoT) devices have become increasingly widespread. Despite their potential of improving multiple application domains, these devices have poor security, which can be explored by attackers to build large-scale botnets. In this work, we propose a host-based approach to detect botnets in IoT devices, named IoTDS (Internet of Things Detection System). It relies on one-class classifiers, which model only the legitimate device behaviour for further detection of deviations, avoiding the manual labelling process. The proposed solution is underpinned by a novel agent-manager architecture based on HTTPS, which prevents the IoT device from being overloaded by the training activities. To analyse the device's behaviour, the approach extracts features from the device's CPU utilisation and temperature, memory consumption, and number of running tasks, meaning that it does not make use of network traffic data. To test our approach, we used an experimental IoT setup containing a device compromised by bot malware. Multiple scenarios were made, including three different IoT device profiles and seven botnets. Four one-class algorithms (Elliptic Envelope, Isolation Forest, Local Outlier Factor, and One-class Support Vector Machine) were evaluated. The results show the proposed system has a good predictive performance for different botnets, achieving a mean F1-score of 94% for the best performing algorithm, the Local Outlier Factor. The system also presented a low impact on the device's energy consumption, and CPU and memory utilisation.

5.
Nano Lett ; 18(8): 4659-4663, 2018 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-29991266

RESUMEN

We performed ferromagnetic resonance and magnetometry experiments to clarify the relationship between two reported magnetic exchange effects arising from interfacial spin-polarized charge transfer in ferromagnetic metal (FM)/molecule bilayers: the magnetic hardening effect and spinterface-stabilized molecular spin chains. To disentangle these effects, we tuned the metal phthalocyanine molecule central site's magnetic moment to enhance or suppress the formation of spin chains in the molecular film. We find that both effects are distinct, and additive. In the process, we extend the list of FM/molecule candidate pairs that are known to generate magnetic exchange effects, experimentally confirm the predicted increase in anisotropy upon molecular adsorption, and show that spin chains within the molecular film can enhance magnetic exchange. Our results confirm, as an echo to progress regarding inorganic spintronic tunnelling, that spintronic tunnelling across structurally ordered organic barriers has been reached through previous magnetotransport experiments.

6.
Pediatr Emerg Care ; 34(2): e35-e38, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29346230

RESUMEN

Chronic hematomas are defined as hematomas with slow, progressive growth over many weeks. They are an extremely rare cause of acute neck swelling in the pediatric population. They consist of an organized central mass of blood with granulation tissue and fibrotic changes peripherally. The presence of a capsule prevents resorption but allows for intracapsular bleeding with subsequent expansion. We describe a case of a 6-year-old girl who presented to the emergency department with a spontaneously occurring left neck mass in the supraclavicular region. A possible neoplasm was suggested on imaging. The patient was referred to a head and neck surgeon, she underwent a thorough workup, and the mass was ultimately surgically excised. Histologically, the mass was confirmed to be a chronic hematoma. The patient recovered uneventfully, and there has been no recurrence.


Asunto(s)
Hematoma/etiología , Biopsia con Aguja Fina , Niño , Enfermedad Crónica , Diagnóstico Diferencial , Femenino , Hematoma/diagnóstico , Hematoma/cirugía , Humanos , Imagen por Resonancia Magnética , Cuello/patología , Tomografía Computarizada por Rayos X
7.
Nat Mater ; 14(10): 981-4, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26191660

RESUMEN

Molecular semiconductors may exhibit antiferromagnetic correlations well below room temperature. Although inorganic antiferromagnetic layers may exchange bias single-molecule magnets, the reciprocal effect of an antiferromagnetic molecular layer magnetically pinning an inorganic ferromagnetic layer through exchange bias has so far not been observed. We report on the magnetic interplay, extending beyond the interface, between a cobalt ferromagnetic layer and a paramagnetic organic manganese phthalocyanine (MnPc) layer. These ferromagnetic/organic interfaces are called spinterfaces because spin polarization arises on them. The robust magnetism of the Co/MnPc spinterface stabilizes antiferromagnetic ordering at room temperature within subsequent MnPc monolayers away from the interface. The inferred magnetic coupling strength is much larger than that found in similar bulk, thin or ultrathin systems. In addition, at lower temperature, the antiferromagnetic MnPc layer induces an exchange bias on the Co film, which is magnetically pinned. These findings create new routes towards designing organic spintronic devices.

8.
Nano Lett ; 15(12): 7921-6, 2015 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-26575946

RESUMEN

We experimentally and theoretically show that the magnetic coupling at room temperature between paramagnetic Mn within manganese phthalocyanine molecules and a Co layer persists when separated by a Cu spacer. The molecule's magnetization amplitude and direction can be tuned by varying the Cu-spacer thickness and evolves according to an interlayer exchange coupling mechanism. Ab initio calculations predict a highly spin-polarized density of states at the Fermi level of this metal-molecule interface, thereby strengthening prospective spintronics applications.

10.
Arch Gerontol Geriatr ; 117: 105206, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37742393

RESUMEN

BACKGROUND: Increased interindividual variability in cognitive performance during aging has been proposed as an indicator of cognitive reserve. OBJECTIVE: To determine if interindividual variability performance in episodic memory (PAL), working memory (SWM), reaction time (RTI), and sustained attention (RVP) could differentiate clusters of differential cognitive performance in healthy young and older adults and search for cognitive tests that most contribute to these differential performances. METHODS: We employed hierarchical cluster and canonical discriminant function analyses of cognitive scores using the Cambridge Neuropsychological Test Automated Battery (CANTAB) to identify cognitive variability in older and young adults using the coefficient of variability of cognitive performances between and within groups. We also analyzed potential influences of age, education, and physical activity. RESULTS: Cluster analysis distinguished groups with differential cognitive performance and correlation analysis revealed coefficient of variability and cognitive performance associations. The greater the coefficient of variability the poorer was cognitive performance in RTI but not in PAL and SWM. Older adults showed diverse trajectories of cognitive decline, and better education or higher percentage of physically active individuals exhibited better cognitive performance in both older and young adults. CONCLUSION: PAL and SWM are the most sensitive tests to investigate the wide age range encompassing older and young adults. In older adults' intragroup analysis PAL showed greater discriminatory capacity, indicating its potential for clinical applications late in life. Our data underscore the importance of studying variability as a tool for early detection of subtle cognitive declines and for interpreting results that deviate from normality.


Asunto(s)
Disfunción Cognitiva , Humanos , Anciano , Adolescente , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/psicología , Envejecimiento/psicología , Memoria a Corto Plazo , Pruebas Neuropsicológicas , Cognición , Función Ejecutiva
11.
Artículo en Inglés | MEDLINE | ID: mdl-38954345

RESUMEN

Sulfate radical-based advanced oxidation processes (SR-AOPs) are renowned for their exceptional capacity to degrade refractory organic pollutants due to their wide applicability, cost-effectiveness, and swift mineralization and oxidation rates. The primary sources of radicals in AOPs are persulfate (PS) and peroxymonosulfate (PMS) ions, sparking significant interest in their mechanistic and catalytic aspects. To develop a novel nanocatalyst for SR-AOPs, particularly for PMS activation, we synthesized carbon-coated FeCo nanoparticles (NPs) using solvothermal methods based on the polyol approach. Various synthesis conditions were investigated, and the NPs were thoroughly characterized regarding their structure, morphology, magnetic properties, and catalytic efficiency. The FeCo phase was primarily obtained at [OH-] / [Metal] = 26 and [Fe] / [Co] = 2 ratios. Moreover, as the [Fe]/[Co] ratio increased, the degree of xylose carbonization to form a carbon coating (hydrochar) on the NPs also increased. The NPs exhibited a spherical morphology with agglomerates of varying sizes. Vibrating-sample magnetometer analysis (VSM) indicated that a higher proportion of iron resulted in NPs with higher saturation magnetization (up to 167.8 emu g-1), attributed to a larger proportion of FeCo bcc phase in the nanocomposite. The best catalytic conditions for degrading 100 ppm Rhodamine B (RhB) included 0.05 g L-1 of NPs, 2 mM PMS, pH 7.0, and a 20-min reaction at 25 °C. Notably, singlet oxygen was the predominant specie formed in the experiments in the SR-AOP, followed by sulfate and hydroxyl radicals. The catalyst could be reused for up to five cycles, retaining over 98% RhB degradation, albeit with increased metal leaching. Even in the first use, dissolved Fe and Co concentrations were 0.8 ± 0.3 and 4.0 ± 0.5 mg L-1, respectively. The FeCo catalyst proved to be effective in dye degradation and offers the potential for further refinement to minimize Co2+ leaching.

12.
Protoplasma ; 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38467939

RESUMEN

The genus Vigna (Leguminosae) comprises about 150 species grouped into five subgenera. The present study aimed to improve the understanding of karyotype diversity and evolution in Vigna, using new and previously published data through different cytogenetic and DNA content approaches. In the Vigna subgenera, we observed a random distribution of rDNA patterns. The 35S rDNA varied in position, from terminal to proximal, and in number, ranging from one (V. aconitifolia, V. subg. Ceratotropis) to seven pairs (V. unguiculata subsp. unguiculata, V. subg. Vigna). On the other hand, the number of 5S rDNA was conserved (one or two pairs), except for V. radiata (V. subg. Ceratotropis), which had three pairs. Genome size was relatively conserved within the genus, ranging from 1C = 0.43 to 0.70 pg in V. oblongifolia and V. unguiculata subsp. unguiculata, respectively, both belonging to V. subg. Vigna. However, we observed a positive correlation between DNA content and the number of 35S rDNA sites. In addition, data from chromosome-specific BAC-FISH suggest that the ancestral 35S rDNA locus is conserved on chromosome 6 within Vigna. Considering the rapid diversification in the number and position of rDNA sites, such conservation is surprising and suggests that additional sites may have spread out from this ancestral locus.

13.
J Am Chem Soc ; 134(20): 8494-506, 2012 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-22509815

RESUMEN

The adsorption of molecular films made of small molecules with a large intrinsic electrical dipole has been explored. The data indicate that such dipolar molecules may be used for altering the interface dipole screening at the metal electrode interface in organic electronics. More specifically, we have investigated the surface electronic spectroscopic properties of zwitterionic molecules containing 12π electrons of the p-benzoquinonemonoimine type, C(6)H(2)(···NHR)(2)(···O)(2)(R = H (1), n-C(4)H(9) (2), C(3)H(6)-S-CH(3) (3), C(3)H(6)-O-CH(3) (4), CH(2)-C(6)H(5) (5)), adsorbed on Au. These molecules are stable zwitterions by virtue of the meta positions occupied by the nitrogen and oxygen substituents on the central ring, respectively. The structures of 2-4 have been determined by single crystal X-ray diffraction and indicate that in these molecules, two chemically connected but electronically not conjugated 6π electron subunits are present, which explains their strong dipolar character. We systematically observed that homogeneous molecular films with thickness as small as 1 nm were formed on Au, which fully cover the surface, even for a variety of R substituents. Preferential adsorption toward the patterned gold areas on SiO(2) substrates was found with 4. Optimum self-assembling of 2 and 5 results in ordered close packed films, which exhibit n-type character, based on the position of the Fermi level close to the conduction band minimum, suggesting high conductivity properties. This new type of self-assembled molecular films offers interesting possibilities for engineering metal-organic interfaces, of critical importance for organic electronics.

14.
Artículo en Inglés | MEDLINE | ID: mdl-36293914

RESUMEN

It is already known the effectiveness of Pilates training on cognitive and functional abilities. It is also known that dual-task exercise and cognitive stimuli improve cognition and functional capacity. However, no previous report combined cognitive stimuli and Pilates in dual task and measured its effects on the cognitive and physical performances of postmenopausal women. OBJECTIVE: To apply an interventional dual-task (PILATES-COG) protocol and to evaluate its influence on memory, language, and functional physical performances on healthy, community-dwelling postmenopausal older women. METHODS: 47 women with amenorrhea for at least 12 months participated in this study. Those allocated on the PILATES-COG group underwent a 12-week, twice a week regimen of 50 min sessions of simultaneous mat Pilates exercise program and cognitive tasks. Cognitive and physical functional performance were assessed. Two-way mixed ANOVA was used for data analysis, and Bonferroni post hoc tests were used for within- and between-group comparisons. RESULTS: The PILATES-COG group showed significant improvement after the intervention in semantic verbal fluency (p < 0.001; ηρ² = 0.268), phonological verbal fluency (p < 0.019; ηρ² = 0.143), immediate memory (p < 0.001; ηρ² = 0.258), evocation memory (p < 0.001 ηρ² = 0.282), lower-limb muscle strength (p < 0.001; ηρ² = 0.447), balance (p < 0.001; ηρ² = 0.398), and dual-ask cost (p < 0.05; ηρ² = 0.111) assessments on healthy, community-dwelling postmenopausal older women. CONCLUSION: This is the first report of a feasible and effective approach using Pilates and cognitive stimulation in dual task for the reduction of age-related cognitive decline and the improvement of physical functional performance in healthy postmenopausal women.


Asunto(s)
Disfunción Cognitiva , Técnicas de Ejercicio con Movimientos , Humanos , Femenino , Anciano , Técnicas de Ejercicio con Movimientos/métodos , Posmenopausia , Actividades Cotidianas , Disfunción Cognitiva/prevención & control , Cognición/fisiología
15.
Adv Mater ; 34(49): e2206688, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36177716

RESUMEN

Recent theory and experiments have showcased how to harness quantum mechanics to assemble heat/information engines with efficiencies that surpass the classical Carnot limit. So far, this has required atomic engines that are driven by cumbersome external electromagnetic sources. Here, using molecular spintronics, an implementation that is both electronic and autonomous is proposed. The spintronic quantum engine heuristically deploys several known quantum assets by having a chain of spin qubits formed by the paramagnetic Co center of phthalocyanine (Pc) molecules electronically interact with electron-spin-selecting Fe/C60 interfaces. Density functional calculations reveal that transport fluctuations across the interface can stabilize spin coherence on the Co paramagnetic centers, which host spin flip processes. Across vertical molecular nanodevices, enduring dc current generation, output power above room temperature, two quantum thermodynamical signatures of the engine's processes, and a record 89% spin polarization of current across the Fe/C60 interface are measured. It is crucially this electron spin selection that forces, through demonic feedback and control, charge current to flow against the built-in potential barrier. Further research into spintronic quantum engines, insight into the quantum information processes within spintronic technologies, and retooling the spintronic-based information technology chain, can help accelerate the transition to clean energy.

16.
Nanoscale ; 13(46): 19466-19473, 2021 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-34792081

RESUMEN

Towards eliminating toxic substances from electronic devices, Croconic Acid (CA) has great potential as a sublimable organic ferroelectric material. While studies on CA thin films are just beginning to emerge, its capability to be integrated in nanodevices remains unexplored. We demonstrate at the laterally nanoscopic scale robust ferroelectric switching of a stable enduring polarization at room temperature in CA thin films, without leakage. The challenging ferroelectric characterization at the nanoscale is performed using a unique combination of piezoresponse force microscopy, polarization switching current spectroscopy and concurrent strain response. This helps rationalize the otherwise asymmetric polarization-voltage hysteresis due to background noise limited undetectable switching currents, which are statistically averaged in macrojunctions but become prevalent at the nanoscale. Apart from successfully estimating the nanoscopic polarization in CA thin films, we show that CA is a promising lead-free organic ferroelectric towards nanoscale device integration. Our results, being valid irrespective of the ferroelectrics' nature; organic or inorganic, pave the way for fundamental understandings and technological applications of nanoscopic polarization reversal mechanisms.

17.
J Dev Orig Health Dis ; 12(2): 286-292, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32345396

RESUMEN

Alterations in the maternal environment may impact on the fetal development. The objective of this study was to investigate the gastrointestinal consequences of maternal hypothyroidism for the male offspring from Wistar rats. The pregnant rats were divided into three groups: control (C - received water), experimental 1 [E1 - received methimazole (MMI) solution] during gestation and lactation, and experimental 2 (E2 - received MMI solution) during gestation. Maternal parameters evaluated: free T3 and T4, bodyweight variation, and water/food intake. Offspring parameters evaluated: litter size, number of male/female, free T3 and T4, stomach area, gastric ulcer susceptibility, small intestine length and weight, small intestine and distal colon motility, the stomach and intestinal weight-body weight ratio (SW/BW-IW/BW), and the accumulation of intestinal fluid. Maternal T3 and T4 from E1 were decreased when compared to the other groups. There were no differences for maternal water/food intake and weight gain, litter size, and number of males and females. Regarding to offspring, free T3, SW/BW, IW/BW, and intestinal fluid accumulation were not different between the groups, but T4 was decreased in E1. However, 30-day-old pups from E1 and E2 were smaller with lower stomach and small intestine. Even more, E1 presented a lower ulcer index when compared to the C, while E2 had a higher distal colon transit. It can be concluded that maternal hypothyroidism impaired the total body development, as well as gastric and intestinal development, besides interfering with the susceptibility to the ulcer and intestinal transit of male offspring from Wistar rats.


Asunto(s)
Motilidad Gastrointestinal , Hipotiroidismo/complicaciones , Exposición Materna/efectos adversos , Úlcera Gástrica/patología , Animales , Animales Recién Nacidos , Femenino , Masculino , Embarazo , Ratas , Ratas Wistar , Úlcera Gástrica/etiología
18.
Lasers Surg Med ; 41(7): 487-91, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19639619

RESUMEN

OBJECTIVES: Laser reshaping of cartilage is an emerging technology aimed at replacing conventional techniques for aesthetic and reconstructive surgery. Little is known about the mechanisms of wound healing following the photothermal heating during laser reshaping and, ultimately, how collagen remodels in the irradiated tissue. Healthy hyaline and elastic cartilage as found in the ear, nose, larynx, and trachea does not express collagen type I which is characteristic of fibro-cartilage and scar tissue. The aim of the study was to determine if collagen I and II gene expression occurs within laser irradiated rabbit septal cartilage. METHODS: Nasal septum harvested from freshly euthanized New Zealand White rabbits were irradiated with an Nd:YAG laser. After 2 weeks in culture, the laser spot and surrounding non-irradiated regions were imaged using immunofluorescence staining and evaluated using reverse transcription polymerase chain reaction (RT-PCR) to determine the presence of collagen I and II, and ascertain collagen I and II gene expression, respectively. RESULTS: All laser irradiated specimens showed a cessation in collagen II gene expression within the center of the laser spot. Collagen II was expressed in the surrounding region encircling the laser spot and within the non-irradiated periphery in all specimens. Immunohistochemistry identified only type II collagen. Neither collagen I gene expression nor immunoreactivity were identified in any specimens regardless or irradiation parameters. CONCLUSIONS: Laser irradiation of rabbit septal cartilage using dosimetry parameters similar to those used in laser reshaping does not result in the detection of either collagen I gene expression or immunoreactivity. Only collagen type II was noted after laser exposure in vitro following cell culture, which suggests that the cellular response to laser irradiation is distinct from that observed in conventional wound healing. Laser irradiation of cartilage can leave an intact collagen matrix which likely allows chondrocyte recovery on an intact scaffold.


Asunto(s)
Colágeno/genética , Terapia por Luz de Baja Intensidad/métodos , Cartílagos Nasales/efectos de la radiación , Tabique Nasal/efectos de la radiación , Animales , Condrocitos/efectos de la radiación , Colágeno/efectos de la radiación , Modelos Animales de Enfermedad , Relación Dosis-Respuesta en la Radiación , Matriz Extracelular/genética , Matriz Extracelular/efectos de la radiación , Regulación de la Expresión Génica , Inmunohistoquímica , Cartílagos Nasales/patología , Tabique Nasal/patología , Conejos , Dosis de Radiación , Regeneración/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y Especificidad
19.
Arch Facial Plast Surg ; 10(1): 38-43, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18209122

RESUMEN

OBJECTIVES: To use multiphoton microscopy to image collagen fibers and matrix structure in nonfixed human keloid tissue and normal human facial skin obtained following surgery and to compare the findings to existing knowledge of normal skin and keloid morphology to determine if this technology is a suitable adjunct for conventional histology. METHODS: Epidermis was removed to expose the fibroblast-rich dermal layer that was then imaged using a multiphoton confocal microscope (Zeiss-Meta 510; Carl Zeiss, Jena, Germany). An 800-nm tunable titanium/sapphire femtosecond laser (Mai-Tai; Newport Co Spectra-Physics, Mountain View, California) was used to excite the tissue; second harmonic generation between 397 and 408 nm and autofluorescent signals were collected. Images were obtained using a Plan-Neofluar x40 oil immersion objective lens and a Plan-Apochromat x63 oil immersion lens. RESULTS: Compared with normal skin, keloids showed disorganized collagen fibers arranged in complex swirls and bundles 20 to 30 microm in diameter. Normal tissue showed collagen fibers as distinct, straight strands less than 10 microm in diameter. Differences between normal and keloid tissue were subtle but apparent. CONCLUSIONS: The value of imaging living tissue is a significant benefit. Because keloids and hypertrophic scars result from altered collagen metabolism, the development of clinical multiphoton microscopy systems may allow examination of wound healing dynamics in vivo and potentially provides a means to monitor therapy without the need for biopsy or the risk of injury to tissue.


Asunto(s)
Cara , Queloide/patología , Queloide/cirugía , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Epidermis/patología , Fibroblastos/ultraestructura , Humanos
20.
Adv Mater ; 29(19)2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28295696

RESUMEN

Materials science and device studies have, when implemented jointly as "operando" studies, better revealed the causal link between the properties of the device's materials and its operation, with applications ranging from gas sensing to information and energy technologies. Here, as a further step that maximizes this causal link, the paper focuses on the electronic properties of those atoms that drive a device's operation by using it to read out the materials property. It is demonstrated how this method can reveal insight into the operation of a macroscale, industrial-grade microelectronic device on the atomic level. A magnetic tunnel junction's (MTJ's) current, which involves charge transport across different atomic species and interfaces, is measured while these atoms absorb soft X-rays with synchrotron-grade brilliance. X-ray absorption is found to affect magnetotransport when the photon energy and linear polarization are tuned to excite FeO bonds parallel to the MTJ's interfaces. This explicit link between the device's spintronic performance and these FeO bonds, although predicted, challenges conventional wisdom on their detrimental spintronic impact. The technique opens interdisciplinary possibilities to directly probe the role of different atomic species on device operation, and shall considerably simplify the materials science iterations within device research.

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