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1.
J Nutr ; 154(2): 395-402, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38081585

RESUMEN

BACKGROUND: Oxylipins are products derived from polyunsaturated fatty acids (PUFAs) that play a role in cardiovascular disease and aging. Fish oil-derived n-3 PUFAs promote the formation of anti-inflammatory and vasodilatory oxylipins; however, there are little data on oxylipins derived from α-linolenic acid (C18:3n-3), the primary plant-derived n-3 PUFA. Walnuts are a source of C18:3n-3. OBJECTIVES: To investigate the effect on serum oxylipins of a diet enriched with walnuts at 15% energy (30-60 g/d; 2.6-5.2 g C18:3n-3/d) for 2 y compared to a control diet (abstention from walnuts) in healthy older males and females (63-79 y). METHODS: The red blood cell proportion of α-linolenic acid was determined by gas chromatography as a measure of compliance. Ultra-performance liquid chromatography-tandem mass spectrometry was used to measure serum concentrations of 53 oxylipins in participants randomly assigned to receive the walnut diet (n = 64) or the control diet (n = 51). Two-year concentration changes (final minus baseline) were log-transformed (base log-10) and standardized (mean-centered and divided by the standard deviation of each variable). Volcano plots were then generated (fold change ≥1.5; false discovery rate ≤0.1). For each oxylipin delta surviving multiple testing, we further assessed between-intervention group differences by analysis of covariance adjusting for age, sex, BMI, and the baseline concentration of the oxylipin. RESULTS: The 2-y change in red blood cell C18:3n-3 in the walnut group was significantly higher than that in the control group (P < 0.001). Compared to the control diet, the walnut diet resulted in statistically significantly greater increases in 3 C18:3n-3-derived oxylipins (9-HOTrE, 13-HOTrE, and 12,13-EpODE) and in the C20:5n-3 derived 14,15-diHETE, and greater reductions of the C20:4n-6-derived 5-HETE, 19-HETE, and 5,6-diHETrE. CONCLUSIONS: Long-term walnut consumption changes the serum oxylipin profile in healthy older persons. Our results add novel mechanistic evidence on the cardioprotective effects of walnuts. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT01634841.


Asunto(s)
Ácidos Grasos Omega-3 , Juglans , Masculino , Femenino , Humanos , Anciano , Anciano de 80 o más Años , Oxilipinas , Ácido alfa-Linolénico , Dieta , Ácidos Grasos Insaturados , Ácidos Grasos Omega-3/farmacología
2.
Nat Commun ; 14(1): 5039, 2023 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-37598209

RESUMEN

With quantum computing devices increasing in scale and complexity, there is a growing need for tools that obtain precise diagnostic information about quantum operations. However, current quantum devices are only capable of short unstructured gate sequences followed by native measurements. We accept this limitation and turn it into a new paradigm for characterizing quantum gate-sets. A single experiment-random sequence estimation-solves a wealth of estimation problems, with all complexity moved to classical post-processing. We derive robust channel variants of shadow estimation with close-to-optimal performance guarantees and use these as a primitive for partial, compressive and full process tomography as well as the learning of Pauli noise. We discuss applications to the quantum gate engineering cycle, and propose novel methods for the optimization of quantum gates and diagnosing cross-talk.

3.
Commun Math Phys ; 397(3): 995-1041, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36743125

RESUMEN

Many quantum information protocols require the implementation of random unitaries. Because it takes exponential resources to produce Haar-random unitaries drawn from the full n-qubit group, one often resorts to t-designs. Unitary t-designs mimic the Haar-measure up to t-th moments. It is known that Clifford operations can implement at most 3-designs. In this work, we quantify the non-Clifford resources required to break this barrier. We find that it suffices to inject O ( t 4 log 2 ( t ) log ( 1 / ε ) ) many non-Clifford gates into a polynomial-depth random Clifford circuit to obtain an ε -approximate t-design. Strikingly, the number of non-Clifford gates required is independent of the system size - asymptotically, the density of non-Clifford gates is allowed to tend to zero. We also derive novel bounds on the convergence time of random Clifford circuits to the t-th moment of the uniform distribution on the Clifford group. Our proofs exploit a recently developed variant of Schur-Weyl duality for the Clifford group, as well as bounds on restricted spectral gaps of averaging operators.

5.
Phys Rev Lett ; 123(20): 200604, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31809071

RESUMEN

One of the outstanding problems in nonequilibrium physics is to precisely understand when and how physically relevant observables in many-body systems equilibrate under unitary time evolution. General equilibration results show that equilibration is generic provided that the initial state has overlap with sufficiently many energy levels. But results not referring to typicality which show that natural initial states actually fulfill this condition are lacking. In this work, we present stringent results for equilibration for systems in which Rényi entanglement entropies in energy eigenstates with finite energy density are extensive for at least some, not necessarily connected, subsystems. Our results reverse the logic of common arguments, in that we derive equilibration from a weak condition akin to the eigenstate thermalization hypothesis, which is usually attributed to thermalization in systems that are assumed to equilibrate in the first place. We put the findings into the context of studies of many-body localization and many-body scars.

6.
Phys Rev Lett ; 121(17): 170502, 2018 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-30411921

RESUMEN

Characterizing quantum processes is a key task in the development of quantum technologies, especially at the noisy intermediate scale of today's devices. One method for characterizing processes is randomized benchmarking, which is robust against state preparation and measurement errors and can be used to benchmark Clifford gates. Compressed sensing techniques achieve full tomography of quantum channels essentially at optimal resource efficiency. In this Letter, we show that the favorable features of both approaches can be combined. For characterizing multiqubit unitary gates, we provide a rigorously guaranteed and practical reconstruction method that works with an essentially optimal number of average gate fidelities measured with respect to random Clifford unitaries. Moreover, for general unital quantum channels, we provide an explicit expansion into a unitary 2-design, allowing for a practical and guaranteed reconstruction also in that case. As a side result, we obtain a new statistical interpretation of the unitarity-a figure of merit characterizing the coherence of a process.

8.
Chirurg ; 87(9): 724-730, 2016 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-27495165

RESUMEN

Knowledge of the anterolateral abdominal wall anatomy is crucial for a surgical approach to the abdominal cavity and for reconstructive surgery of abdominal wall defects. Furthermore it can help the surgeon ensure optimal surgical results by avoiding anatomical complications. This overview presents the surgical relevant anatomy and emphasizes surgical principles and pitfalls in abdominal wall surgery.


Asunto(s)
Pared Abdominal/anatomía & histología , Pared Abdominal/cirugía , Técnicas de Cierre de Herida Abdominal , Músculos Abdominales/anatomía & histología , Músculos Abdominales/cirugía , Humanos , Hernia Incisional/etiología , Hernia Incisional/prevención & control , Hernia Incisional/cirugía , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/cirugía , Técnicas de Sutura
9.
Oncogene ; 35(38): 4981-9, 2016 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-26996665

RESUMEN

A number of naturally occurring isoforms of the tumour suppressor protein p53 have been discovered, which appear to have differing roles in tumour prevention or promotion. We are investigating the tumour-promoting activities of the Δ133p53 isoform using our mouse model of Δ133p53 (Δ122p53). Here, we report that tumours from Δ122p53 homozygous mice show evidence of invasion and metastasis and that Δ122p53 promotes migration though a 3-dimensional collagen matrix. We also show that Δ122p53 and Δ133p53 promote cell migration in scratch wound and Transwell assays, similar to the 'gain-of-function' phenotypes seen with mutant p53. Using the well-defined B16 mouse melanoma metastatic model, we show that Δ122p53 leads to faster generation of lung metastases. The increased migratory phenotypes are dependent on secreted factors, including the cytokine interleukin-6 and the chemokine CCL2. We propose that Δ122p53 (and Δ133p53) acts in a similar manner to 'gain-of-function' mutant p53 proteins to promote migration, invasion and metastasis, which may contribute to poor survival in patients with Δ133p53-expressing tumours.


Asunto(s)
Quimiocina CCL2/genética , Interleucina-6/genética , Neoplasias Pulmonares/genética , Melanoma Experimental/genética , Proteína p53 Supresora de Tumor/genética , Animales , Movimiento Celular/genética , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/secundario , Melanoma Experimental/patología , Ratones , Mutación , Invasividad Neoplásica/genética , Invasividad Neoplásica/patología , Metástasis de la Neoplasia , Isoformas de Proteínas
10.
Artículo en Inglés | MEDLINE | ID: mdl-28596889

RESUMEN

BACKGROUND: Little has been reported about service provision for children with autism in low-income countries. This study explored the current service provision for children with autism and their families in Ethiopia, the existing challenges and urgent needs, and stakeholders' views on the best approaches to further develop services. METHODS: A situational analysis was conducted based on (i) qualitative interviews with existing service providers; (ii) consultation with a wider group of stakeholders through two stakeholder workshops; and (iii) information available in the public domain. Findings were triangulated where possible. RESULTS: Existing diagnostic and educational services for children with autism are scarce and largely confined to Ethiopia's capital city, with little provision in rural areas. Families of children with autism experience practical and psychosocial challenges, including severe stigma. Informants further raised the lack of culturally and contextually appropriate autism instruments as an important problem to be addressed. The study informants and local stakeholders provided several approaches for future service provision expansion, including service decentralisation, mental health training and awareness raising initiatives. CONCLUSIONS: Services for children with autism in Ethiopia are extremely limited; appropriate care for these children is further impeded by stigma and lack of awareness. Ethiopia's plans to scale up mental healthcare integrated into primary care provide an opportunity to expand services for children with autism and other developmental disorders. These plans, together with the additional strategies outlined in this paper can help to address the current service provision gaps and may also inform service enhancement approaches in other low-income countries.

11.
Nutr Metab Cardiovasc Dis ; 25(1): 36-45, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25183453

RESUMEN

BACKGROUND AND AIMS: Moderate alcohol consumption exerts a cardioprotective effect, but no studies have evaluated the alcohol-independent cardiovascular effects of the non-alcoholic components of beer. We aimed to evaluate the effects of ethanol and the phenolic compounds of beer on classical and novel cardiovascular risk factors. METHODS AND RESULTS: Thirty-three high risk male volunteers were included in a randomized, crossover feeding trial. After a washout period, all subjects received beer (30 g alcohol/d, 660 mL), the equivalent amount of polyphenols as non-alcoholic beer (990 mL), and gin (30 g alcohol/d, 100 mL) for 4 weeks. All outcomes were evaluated before and after each intervention period. Moderate alcohol consumption increased serum HDL-cholesterol (∼5%), ApoA-I (∼6%), ApoA-II (∼7%) and adiponectin (∼7%), and decreased serum fibrinogen (∼8%), and interleukin (IL)-5 (∼14%) concentrations, whereas the non-alcoholic fraction of beer (mainly polyphenols) increased the receptor antagonist of IL-1 (∼24%), and decreased lymphocyte expression of lymphocyte function-associated antigen-1 (∼11%), lymphocyte and monocyte expression of Sialil-Lewis X (∼16%) and monocyte expression of CCR2 (∼31%), and tumor necrosis factor (TNF)-ß (∼14%) and IL-15 (∼22%) plasma concentrations. No changes were observed in glucose metabolism parameters or in body weight and adiposity parameters. CONCLUSION: The phenolic content of beer reduces leukocyte adhesion molecules and inflammatory biomarkers, whereas alcohol mainly improves the lipid profile and reduces some plasma inflammatory biomarkers related to atherosclerosis.


Asunto(s)
Consumo de Bebidas Alcohólicas , Aterosclerosis/prevención & control , Cerveza/análisis , Polifenoles/uso terapéutico , Adiponectina/agonistas , Adiponectina/sangre , Anciano , Bebidas Alcohólicas/análisis , Apolipoproteínas A/agonistas , Apolipoproteínas A/sangre , Aterosclerosis/sangre , Aterosclerosis/inmunología , Bebidas/análisis , Biomarcadores/sangre , Biomarcadores/química , Enfermedades Cardiovasculares/epidemiología , HDL-Colesterol/agonistas , HDL-Colesterol/sangre , Estudios Cruzados , Alimentos Fortificados/análisis , Humanos , Mediadores de Inflamación/antagonistas & inhibidores , Mediadores de Inflamación/sangre , Masculino , Persona de Mediana Edad , Polifenoles/administración & dosificación , Polifenoles/análisis , Factores de Riesgo , España/epidemiología
12.
Phys Rev Lett ; 113(3): 035001, 2014 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-25083648

RESUMEN

The mechanisms for accelerating electrons from thermal to relativistic energies in the terrestrial magnetosphere, on the sun, and in many astrophysical environments have never been verified. We present the first direct observation of two processes that, in a chain, cause this acceleration in Earth's outer radiation belt. The two processes are parallel acceleration from electron-volt to kilovolt energies by parallel electric fields in time-domain structures (TDS), after which the parallel electron velocity becomes sufficiently large for Doppler-shifted upper band whistler frequencies to be in resonance with the electron gyration frequency, even though the electron energies are kilovolts and not hundreds of kilovolts. The electrons are then accelerated by the whistler perpendicular electric field to relativistic energies in several resonant interactions. TDS are packets of electric field spikes, each spike having duration of a few hundred microseconds and containing a local parallel electric field. The TDS of interest resulted from nonlinearity of the parallel electric field component in oblique whistlers and consisted of ∼ 0.1 msec pulses superposed on the whistler waveform with each such spike containing a net parallel potential the order of 50 V. Local magnetic field compression from remote activity provided the free energy to drive the two processes. The expected temporal correlations between the compressed magnetic field, the nonlinear whistlers with their parallel electric field spikes, the electron flux and the electron pitch angle distributions were all observed.

13.
Horm Metab Res ; 46(1): 41-7, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24043573

RESUMEN

Regulation of adipokines in lean adults without metabolic disease and without eating disorders has not been comprehensively elucidated. We hypothesized that some of the established associations of these adipocyte-secreted proteins with anthropometric and biochemical measures of glucose homeostasis, lipid metabolism, renal function, as well as inflammation, differ in healthy and low weight adults as compared to overweight/obese patients. Eighty-one subjects with a body mass-index below 22.0 kg/m2 and without malnutrition or eating disorders, as well as fifty overweight/obese patients, were recruited for the study. Serum concentrations of seven adipokines (adiponectin, leptin, adipocyte fatty acid-binding protein [AFABP], chemerin, fibroblast growth factor [FGF]-21, resistin, retinol-binding protein [RBP]-4) were measured by enzyme-linked immunosorbent assays. Lean probands had significantly higher levels of adiponectin and resistin, as well as lower levels of leptin, AFABP, and RBP-4, as compared to overweight/obese subjects. Serum concentrations of adiponectin, leptin, AFABP, chemerin, and resistin were significantly higher in lean women as compared to men (p<0.05). In lean subjects, fasting insulin independently predicted leptin and resistin concentrations. Furthermore, C-reactive protein was independently associated with circulating AFABP and chemerin. Moreover, lean body mass was an independent predictor of leptin, fat mass predicted AFABP levels, whereas RBP-4 was independently correlated to age and triglycerides. In addition, high density lipoprotein cholesterol predicted AFABP. Our results support the notion that several of these adipokines are regulated in a different manner in lean adults as compared to overweight/obese subjects and patients with eating disorders.


Asunto(s)
Adipoquinas/sangre , Salud , Delgadez/sangre , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Obesidad/sangre , Análisis de Regresión , Estadísticas no Paramétricas
14.
Acta Biomater ; 10(2): 996-1004, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24211732

RESUMEN

Resorbable magnesium-based implants hold great promise for various biomedical applications, such as osteosynthesis and coronary stenting. They also offer a new therapeutic option for the treatment of chronic rhinosinusitis, but little data is yet available regarding the use of magnesium in the nasal cavity. To model this field of application, primary porcine nasal epithelial cells were used to test the biocompatibility of degrading pure magnesium and investigate whether the degradation products may also affect cellular metabolism. Magnesium specimens did not induce apoptosis and we found no major influence on enzyme activities or protein synthesis, but cell viability was reduced and elevated interleukin 8 secretion indicated proinflammatory reactions. Necrotic damage was most likely due to osmotic stress, and our results suggest that magnesium ion build-up is also involved in the interleukin 8 release. Furthermore, the latter seems to be mediated, at least in part, by the p38 signaling pathway. These effects probably depended on the accumulation of very high concentrations of magnesium ions in the in vitro set-up, which might not be achieved in vivo, although we cannot exclude that further, as yet unknown, factors played a role in the inflammatory response during the degradation process. In conclusion, the biocompatibility of pure magnesium with cells in the immediate vicinity appears less ideal than is often supposed, and this needs to be considered in the evaluation of magnesium materials containing additional alloying elements.


Asunto(s)
Células Epiteliales/patología , Inflamación/patología , Magnesio/efectos adversos , Nariz/patología , Animales , Biodegradación Ambiental , Diferenciación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Células Epiteliales/efectos de los fármacos , Células Epiteliales/enzimología , Células Epiteliales/metabolismo , Interleucina-8/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Necrosis , Sus scrofa
15.
Phys Rev Lett ; 111(23): 235002, 2013 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-24476280

RESUMEN

Huge numbers of double layers carrying electric fields parallel to the local magnetic field line have been observed on the Van Allen probes in connection with in situ relativistic electron acceleration in the Earth's outer radiation belt. For one case with adequate high time resolution data, 7000 double layers were observed in an interval of 1 min to produce a 230,000 V net parallel potential drop crossing the spacecraft. Lower resolution data show that this event lasted for 6 min and that more than 1,000,000 volts of net parallel potential crossed the spacecraft during this time. A double layer traverses the length of a magnetic field line in about 15 s and the orbital motion of the spacecraft perpendicular to the magnetic field was about 700 km during this 6 min interval. Thus, the instantaneous parallel potential along a single magnetic field line was the order of tens of kilovolts. Electrons on the field line might experience many such potential steps in their lifetimes to accelerate them to energies where they serve as the seed population for relativistic acceleration by coherent, large amplitude whistler mode waves. Because the double-layer speed of 3100 km/s is the order of the electron acoustic speed (and not the ion acoustic speed) of a 25 eV plasma, the double layers may result from a new electron acoustic mode. Acceleration mechanisms involving double layers may also be important in planetary radiation belts such as Jupiter, Saturn, Uranus, and Neptune, in the solar corona during flares, and in astrophysical objects.

16.
J Endocrinol Invest ; 35(6): 562-5, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21791968

RESUMEN

BACKGROUND: Preeclampsia (PE) is associated with facets of the metabolic syndrome and an increased future metabolic and cardiovascular risk for mother and newborn. Recently, zinc-α2-glycoprotein (ZAG) has been proposed as a new adipokine involved in the pathogenesis of obesity. AIM: In the current study, we investigated ZAG serum levels in PE patients as compared to healthy gestational age-matched controls. SUBJECTS AND METHODS: We quantified serum concentrations of ZAG in patients with PE (no.=37) as compared to healthy gestational age-matched controls (no.=37) by enzyme-linked immunosorbent assay. Furthermore, association of this adipokine with renal function, glucose and lipid metabolism, as well as inflammation was studied. RESULTS: Median serum ZAG levels were 1.4-fold higher in PE patients (58.8 mg/l) as compared to controls (41.9 mg/l) (p<0.01). Furthermore, circulating ZAG was positively correlated to systolic and diastolic blood pressure, creatinine, triglycerides, and leptin in univariate analyses. In multiple regression analysis, creatinine remained independently associated with ZAG. CONCLUSIONS: We demonstrate that maternal ZAG serum concentrations are significantly increased in PE. Furthermore, renal function is an independent predictor of circulating ZAG.


Asunto(s)
Adipoquinas/sangre , Biomarcadores/sangre , Preeclampsia/sangre , Proteínas de Plasma Seminal/sangre , Adulto , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Recién Nacido , Preeclampsia/diagnóstico , Embarazo , Factores de Riesgo , Adulto Joven , Zn-alfa-2-Glicoproteína
17.
Neuropsychol Rev ; 21(4): 360-89, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21989834

RESUMEN

Diagnosis, intervention and support for people with autism can be assisted by research into the aetiology of the condition. Twin and family studies indicate that autism spectrum conditions are highly heritable; genetic relatives of people with autism often show milder expression of traits characteristic for autism, referred to as the Broader Autism Phenotype (BAP). In the past decade, advances in the biological and behavioural sciences have facilitated a more thorough examination of the BAP from multiple levels of analysis. Here, the candidate phenotypic traits delineating the BAP are summarised, including key findings from neuroimaging studies examining the neural substrates of the BAP. We conclude by reviewing the value of further research into the BAP, with an emphasis on deriving heritable endophenotypes which will reliably index autism susceptibility and offer neurodevelopmental mechanisms that bridge the gap between genes and a clinical autism diagnosis.


Asunto(s)
Trastorno Autístico/clasificación , Fenotipo , Adulto , Trastorno Autístico/diagnóstico , Trastorno Autístico/genética , Niño , Función Ejecutiva , Predisposición Genética a la Enfermedad , Humanos , Relaciones Interpersonales , Lenguaje , Neuroimagen , Conducta Social , Conducta Estereotipada
18.
Circulation ; 121(1): 123-31, 2010 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-20026782

RESUMEN

BACKGROUND: Endothelial dysfunction is the initiating event of atherosclerosis. The expression of connexin40 (Cx40), an endothelial gap junction protein, is decreased during atherogenesis. In the present report, we sought to determine whether Cx40 contributes to the development of the disease. METHODS AND RESULTS: Mice with ubiquitous deletion of Cx40 are hypertensive, a risk factor for atherosclerosis. Consequently, we generated atherosclerosis-susceptible mice with endothelial-specific deletion of Cx40 (Cx40del mice). Cx40del mice were indeed not hypertensive. The progression of atherosclerosis was increased in Cx40del mice after 5 and 10 weeks of a high-cholesterol diet, and spontaneous lesions were observed in the aortic sinuses of young mice without such a diet. These lesions showed monocyte infiltration into the intima, increased expression of vascular cell adhesion molecule-1, and decreased expression of the ecto-enzyme CD73 in the endothelium. The proinflammatory phenotype of Cx40del mice was confirmed in another model of induced leukocyte recruitment from the lung microcirculation. Endothelial CD73 is known to induce antiadhesion signaling via the production of adenosine. We found that reducing Cx40 expression in vitro with small interfering RNA or antisense decreased CD73 expression and activity and increased leukocyte adhesion to mouse endothelial cells. These effects were reversed by an adenosine receptor agonist. CONCLUSIONS: Cx40-mediated gap junctional communication contributes to a quiescent nonactivated endothelium by propagating adenosine-evoked antiinflammatory signals between endothelial cells. Alteration in this mechanism by targeting Cx40 promotes leukocyte adhesion to the endothelium, thus accelerating atherosclerosis.


Asunto(s)
5'-Nucleotidasa/metabolismo , Aterosclerosis/fisiopatología , Conexinas/genética , Células Endoteliales/patología , Vasculitis/fisiopatología , Animales , Aterosclerosis/inmunología , Aterosclerosis/patología , Adhesión Celular/inmunología , Células Cultivadas , Conexinas/metabolismo , Células Endoteliales/metabolismo , Uniones Comunicantes/metabolismo , Proteínas Fluorescentes Verdes/genética , Ratones , Ratones Transgénicos , Monocitos/metabolismo , Monocitos/patología , ARN Interferente Pequeño , Transducción de Señal/inmunología , Vasculitis/inmunología , Vasculitis/patología , Proteína alfa-5 de Unión Comunicante
19.
Phys Rev Lett ; 85(1): 94-7, 2000 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-10991167

RESUMEN

We study a transverse instability of the nonlinear equilibria known as electron phase-space holes in the presence of a magnetic field. The instability is intrinsically two dimensional and is determined by the dynamics of the trapped electrons. It depends on hole amplitudes, ambient magnetic fields, and the perpendicular velocity spread. The long-standing hole stability problem in multiple dimensions can be characterized by the gyro-to-bounce frequency ratio. A low ratio associated with a small perpendicular velocity spread results in a disintegration of the positive potential spikes.

20.
J Bone Miner Res ; 15(1): 147-54, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10646124

RESUMEN

Up to 60% of patients receiving their first infusion of the bisphosphonate pamidronate experience an acute-phase reaction. In this study, we used flow cytometry to determine the effects of pamidronate treatment on circulating lymphocyte subpopulations, and we investigated whether pamidronate and ibandronate treatment affect lymphocyte subpopulations differently. Twenty patients received a pamidronate infusion, 20 patients received intravenously injected ibandronate, and 10 controls received a clodronate infusion. Pamidronate treatment was followed by a significant increase in median body temperature at the 10-hour measurement and a significant decrease in counts of circulating lymphocytes, natural killer cells, T cells, and CD4+ and CD8+ T-cell subsets. Ibandronate treatment did not affect median body temperature, and it was associated at the 10-hour measurement with maximum increases in total lymphocyte count, B cells, T cells, and CD4+ and CD8+ T-cell subsets. Thus, there is a substantial difference in the hematologic response to initial treatments with pamidronate and ibandronate. Clodronate treatment did not induce changes in body temperature or significantly affect the number of circulating T cells and NK cells. The reduction in lymphocyte subsets after initial pamidronate therapy might be mediated by the release of tumor necrosis factor alpha, whose source in the acute-phase reaction could be T cells.


Asunto(s)
Difosfonatos/farmacología , Subgrupos Linfocitarios/efectos de los fármacos , Adulto , Anciano , Anciano de 80 o más Años , Antígenos CD/inmunología , Antígenos de Diferenciación de Linfocitos T/inmunología , Ácido Clodrónico/farmacología , Femenino , Humanos , Ácido Ibandrónico , Lectinas Tipo C , Masculino , Persona de Mediana Edad , Pamidronato , Estudios Prospectivos , Factor de Necrosis Tumoral alfa/metabolismo
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