76 research outputs found
Connexin43 hemichannels in satellite glial cells, can they influence sensory neuron activity?
Indexación: Scopus.In this review article, we summarize the current insight on the role of Connexin- and Pannexin-based channels as modulators of sensory neurons. The somas of sensory neurons are located in sensory ganglia (i.e., trigeminal and nodose ganglia). It is well known that within sensory ganglia, sensory neurons do not form neither electrical nor chemical synapses. One of the reasons for this is that each soma is surrounded by glial cells, known as satellite glial cells (SGCs). Recent evidence shows that connexin43 (Cx43) hemichannels and probably pannexons located at SGCs have an important role in paracrine communication between glial cells and sensory neurons. This communication may be exerted via the release of bioactive molecules from SGCs and their subsequent action on receptors located at the soma of sensory neurons. The glio-neuronal communication seems to be relevant for the establishment of chronic pain, hyperalgesia and pathologies associated with tissue inflammation. Based on the current literature, it is possible to propose that Cx43 hemichannels expressed in SGCs could be a novel pharmacological target for treating chronic pain, which need to be directly evaluated in future studies.https://www.frontiersin.org/articles/10.3389/fnmol.2017.00374/ful
INFLUENCE OF CELL WALL CALCIUM CONTENT IN FRUIT FIRMNESS DURING THE RIPENING OF PLUMS (PRUNUS DOMESTICA L.).
‘Rainha Claudia Verde’ is a regional cultivar of Prunus domestica L. well adapted to a specific region in the south of Portugal. In order to understand the postharvest behavior of this cultivar produced in different orchards, cell wall poly-saccharides and cell wall calcium fruit content were studied during ripening in two consecutive years. During harvest period pectic fractions soluble in water, carbonate and KOH were prepared from alcohol-insoluble residue (AIR) of plums. Galacturonic and neutral sugars contents were measured during fruit ripening and fruit firmness was also evaluated. The calcium fruit level was determined in the AIR during harvest season as well as in dry matter. Fruit firmness was significantly higher in the second year and was probably related with calcium fruit content and pectic polysaccharides. There was a significant difference in calcium fruit content between orchards, and this might influence the overall fruit texture during the postharvest period. During fruit ripening water soluble pectic polysaccharides did not change significantly, which corresponded with the small decrease in tissue firmness. The occurrence in the supernatant of the cellulosic residue of highly branched polysaccharides might be the consequence of matrix material associated with microfibrilar phase. Depolymerization of the hemicellulosic fraction was not evident during plum ripening. The loss of fruit firmness is a consequence of many cellular events which are influenced by external factors. The knowledge of calcium content in the cell wall and the pectic poly¬saccharides could be of great importance to local farmers to predict fruit texture
Baja morbilidad en niños operados de nefrectomía con técnica laparoscópica transperitoneal de 3 puertos
ResumenAntecedentesAunque la nefrectomía laparoscópica actualmente se considera el estándar de oro en la cirugía renal del adulto, aún existe controversia de su papel en la población pediátrica. La nefrectomía laparoscópica ha demostrado ser un procedimiento efectivo y seguro comparado con el abordaje abierto.ObjetivoPresentar una serie de casos de pacientes pediátricos con diversas enfermedades renales, tratados con nefrectomía laparoscópica transperitoneal.Materiales y métodosIncluye 22 pacientes pediátricos sometidos a nefrectomía laparoscópica transperitoneal. Todos los casos se realizaron vía laparoscópica con abordaje transperitoneal usando 3 puertos.ResultadosTodos los riñones se removieron satisfactoriamente. El promedio de tiempo operatorio fue de 142min. En 21 de los 22 casos no hubo complicaciones que requirieran conversión cirugía abierta. Se inició dieta y deambulación el mismo día de la cirugía en todos los pacientes y se dio de alta a 20 de los 21 pacientes sin conversión a los 2 días postoperatorios.ConclusionesEn nuestra serie de casos reportamos el abordaje transperitoneal laparoscópico para nefrectomía usando una técnica con 3 puertos que puede ser usada con seguridad en la población pediátrica con los mismos resultados y seguridad que otros procedimientos laparoscópicos. Es una excelente alternativa a la cirugía abierta tradicional y debe ser considerada para disminuir el riesgo quirúrgico.AbstractBackgroundEven though laparoscopic nephrectomy is considered the gold standard in renal surgery in the adult, its role in the pediatric population is still a subject of debate. Laparoscopic nephrectomy has been shown to be a safe and effective procedure, compared with the open approach.AimTo present a case series of pediatric patients with different renal pathologies treated through transperitoneal laparoscopic nephrectomy.Material and methodsTwenty-two pediatric patients that underwent transperitoneal laparoscopic nephrectomy were included in the study. All of the cases underwent the 3-port transperitoneal laparoscopic approach.ResultsAll the kidneys were satisfactorily removed and the mean surgery duration was 142 min. There were no complications requiring conversion to open surgery in 21 of the 22 cases. Oral diet and ambulation were begun the same day of the surgery for all patients. Twenty of the 21 patients that did not require conversion were released on the second postoperative day.ConclusionsWe report herein on the transperitoneal laparoscopic approach for nephrectomy with the 3-port technique. It can be performed in the pediatric population with the same results and safety as other laparoscopic procedures and is an excellent alternative to traditional open surgery. This procedure should be considered for reducing surgical risk
Cosmic-ray acceleration in supernova remnants: non-linear theory revised
A rapidly growing amount of evidences, mostly coming from the recent
gamma-ray observations of Galactic supernova remnants (SNRs), is seriously
challenging our understanding of how particles are accelerated at fast shocks.
The cosmic-ray (CR) spectra required to account for the observed phenomenology
are in fact as steep as , i.e., steeper than the
test-particle prediction of first-order Fermi acceleration, and significantly
steeper than what expected in a more refined non-linear theory of diffusive
shock acceleration. By accounting for the dynamical back-reaction of the
non-thermal particles, such a theory in fact predicts that the more efficient
the particle acceleration, the flatter the CR spectrum. In this work we put
forward a self-consistent scenario in which the account for the magnetic field
amplification induced by CR streaming produces the conditions for reversing
such a trend, allowing --- at the same time --- for rather steep spectra and CR
acceleration efficiencies (about 20%) consistent with the hypothesis that SNRs
are the sources of Galactic CRs. In particular, we quantitatively work out the
details of instantaneous and cumulative CR spectra during the evolution of a
typical SNR, also stressing the implications of the observed levels of
magnetization on both the expected maximum energy and the predicted CR
acceleration efficiency. The latter naturally turns out to saturate around
10-30%, almost independently of the fraction of particles injected into the
acceleration process as long as this fraction is larger than about .Comment: 24 pages, 5 figures, accepted for publication in JCA
NOTAS MICOLOGICAS: Hortaea werneckii EN AMBIENTES SALINOS DEL NORTE CHILENO
Mediante determinaciones morfológicas y fsiológicas, se describe el primer aislamienlo del hongo dematiáceo le vaduriforme Hortaea werneckii en aguade mar y moluscos del norte chileno (Antofagasta, IIRegión).Se comenta al mismo tiempo junto a los aportes de la literatura, algunos datos ecológicos, epidemiológicos y taxonómicos de esta levadura negra
Magnetic fields in cosmic particle acceleration sources
We review here some magnetic phenomena in astrophysical particle accelerators
associated with collisionless shocks in supernova remnants, radio galaxies and
clusters of galaxies. A specific feature is that the accelerated particles can
play an important role in magnetic field evolution in the objects. We discuss a
number of CR-driven, magnetic field amplification processes that are likely to
operate when diffusive shock acceleration (DSA) becomes efficient and
nonlinear. The turbulent magnetic fields produced by these processes determine
the maximum energies of accelerated particles and result in specific features
in the observed photon radiation of the sources. Equally important, magnetic
field amplification by the CR currents and pressure anisotropies may affect the
shocked gas temperatures and compression, both in the shock precursor and in
the downstream flow, if the shock is an efficient CR accelerator. Strong
fluctuations of the magnetic field on scales above the radiation formation
length in the shock vicinity result in intermittent structures observable in
synchrotron emission images. Resonant and non-resonant CR streaming
instabilities in the shock precursor can generate mesoscale magnetic fields
with scale-sizes comparable to supernova remnants and even superbubbles. This
opens the possibility that magnetic fields in the earliest galaxies were
produced by the first generation Population III supernova remnants and by
clustered supernovae in star forming regions.Comment: 30 pages, Space Science Review
A functional IL1RL1 variant regulates corticosteroid-induced sST2 expression in ulcerative colitis
Indexación: Web of Science; Scopus.The ST2/IL33 signalling pathway has been associated with ulcerative colitis (UC). ST2, encoded by the IL1RL1 gene, is expressed as both a membrane-anchored receptor (ST2L) activated by IL33 and as a soluble receptor (sST2) with anti-inflammatory properties. In UC patients, sST2 is further increased by corticosteroid treatment; however, the glucocorticoid-mediated molecular regulation remains unknown. We therefore tested whether genetic variants in the IL1RL1 distal promoter are involved in UC and affect glucocorticoid-mediated ST2 expression. Serum ST2 levels and genetic variants in the IL1RL1 distal promoter were examined by ELISA and PCR sequencing in UC patients receiving corticosteroids. Glucocorticoid-mediated ST2 production was evaluated in intestinal mucosa cultures. Molecular regulation of glucocorticoid-mediated ST2 was assessed by RT-qPCR, ChIP assay and luciferase reporter assay. Dexamethasone effect on ST2 transcript expression was analyzed in leukocytes and related to IL1RL1 variants. Sequencing of a distal IL1RL1 promoter region demonstrated that SNPs rs6543115(C) and rs6543116(A) are associated with increased sST2 in UC patients on corticosteroids. Dexamethasone up-regulated sST2 transcription through interaction with the glucocorticoid-response element (GRE) carrying rs6543115(C) variant. Our data indicate that IL1RL1 SNPs rs6543115(C) confer susceptibility to UC and is contained in the GRE, which may modulate glucocorticoid-induced sST2 expression.https://www.nature.com/articles/s41598-017-10465-
Understanding hadronic gamma-ray emission from supernova remnants
We aim to test the plausibility of a theoretical framework in which the
gamma-ray emission detected from supernova remnants may be of hadronic origin,
i.e., due to the decay of neutral pions produced in nuclear collisions
involving relativistic nuclei. In particular, we investigate the effects
induced by magnetic field amplification on the expected particle spectra,
outlining a phenomenological scenario consistent with both the underlying
Physics and the larger and larger amount of observational data provided by the
present generation of gamma experiments, which seem to indicate rather steep
spectra for the accelerated particles. In addition, in order to study to study
how pre-supernova winds might affect the expected emission in this class of
sources, the time-dependent gamma-ray luminosity of a remnant with a massive
progenitor is worked out. Solid points and limitations of the proposed scenario
are finally discussed in a critical way.Comment: 30 pages, 5 figures; Several comments, references and a figure added.
Some typos correcte
Association of STAT4 with rheumatoid arthritis:A replication study in three European populations
OBJECTIVE: This study was undertaken to investigate the previously reported association of the STAT4 polymorphism rs7574865 with rheumatoid arthritis (RA) in 3 different European populations from Spain, Sweden, and The Netherlands, comprising a total of 2,072 patients and 2,474 controls. METHODS: Three different cohorts were included in the study: 923 RA patients and 1,296 healthy controls from Spain, 273 RA patients and 285 healthy controls from Sweden, and 876 RA patients and 893 healthy controls from The Netherlands. DNA from patients and controls was obtained from peripheral blood. Samples were genotyped for the STAT4 single-nucleotide polymorphism rs7574865 using a TaqMan 5'-allele discrimination assay. The chi-square test was performed to compare allele and genotype distributions. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated. RESULTS: We observed a significantly increased frequency of the minor T allele in RA patients compared with healthy controls in the Spanish population (24.8% versus 20.8%; P = 0.001, OR 1.26 [95% CI 1.09-1.45]). This association was confirmed in both the Swedish population (P = 0.03, OR 1.35 [95% CI 1.03-1.77]) and the Dutch population (P = 0.03, OR 1.45 [95% CI 1.21-1.73]). The overall P value for all 3 populations was 9.79 x 10(-6) (OR 1.25 [95% CI 1.13-1.37]). No association between rs7574865 and the presence of rheumatoid factor or anti-cyclic citrullinated peptide autoantibodies was observed. A meta-analysis of all published STAT4 associations revealed an OR of 1.25 (95% CI 1.19-1.33) (P = 1 x 10(-5)). CONCLUSION: Our findings indicate an association between the STAT4 polymorphism rs7574865 and RA in 3 different populations, from Spain, Sweden, and The Netherlands, thereby confirming previous data
Non-Gaussianities from Perturbing Recombination
We approximately compute the bispectrum induced on the CMB temperature by
fluctuations in the standard recombination epoch. Of all the second order
sources that can induce non-Gaussianity during recombination, we concentrate on
those proportional to the perturbation in the free electron density, which is
about a factor of 5 larger than the other first order perturbations. This term
induces some non-Gaussianity by delaying the time of recombination and by
changing the photon diffusion scale. We find that the signal is not scale
invariant, peaked on squeezed triangles with the smaller multipole around the
scale of the first acoustic peak, and that its size corresponds to an effective
f_NL ~ -3.5, which could be marginally detected by Planck if both temperature
and polarization are measured.Comment: 37 pages, 13 figures. v2: Corrected algebraic mistake, numerical
results marginally affected; added reference
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