RESUMEN

We generalize the particle-conserving dynamics method of de las Heras et al. [J. Phys.: Condens. Matter 28, 244024 (2016)JCOMEL0953-898410.1088/0953-8984/28/24/244024] to binary mixtures and apply this to hard rods in one dimension. Considering the case of one species consisting of only one particle enables us to address the tagged-particle dynamics. The time-evolution of the species-labeled density profiles is compared to exact Brownian dynamics and (grand-canonical) dynamical density functional theory. The particle-conserving dynamics yields improved results over the dynamical density functional theory and well reproduces the simulation data at short and intermediate times. However, the neglect of a strict particle order (due to the fundamental statistical assumption of ergodicity) leads to errors at long times for our one-dimensional setup. The isolated study of that error makes clear the fundamental limitations of (adiabatic) density-based theoretical approaches when applied to systems of any dimension for which particle caging is a dominant physical mechanism.

RESUMEN

Using overdamped Brownian dynamics simulations we investigate the isotropic-nematic (IN) transition of self-propelled rods in three spatial dimensions. For two well-known model systems (Gay-Berne potential and hard spherocylinders) we find that turning on activity moves to higher densities the phase boundary separating an isotropic phase from a (nonpolar) nematic phase. This active IN phase boundary is distinct from the boundary between isotropic and polar-cluster states previously reported in two-dimensional simulation studies and, unlike the latter, is not sensitive to the system size. We thus identify a generic feature of anisotropic active particles in three dimensions.

RESUMEN

The escape rate of a Brownian particle over a potential barrier is accurately described by the Kramers theory. A quantitative theory explicitly taking the activity of Brownian particles into account has been lacking due to the inherently out-of-equilibrium nature of these particles. Using an effective equilibrium approach [Farage et al., Phys. Rev. E 91, 042310 (2015)PLEEE81539-375510.1103/PhysRevE.91.042310] we study the escape rate of active particles over a potential barrier and compare our analytical results with data from direct numerical simulation of the colored noise Langevin equation. The effective equilibrium approach generates an effective potential that, when used as input to Kramers rate theory, provides results in excellent agreement with the simulation data.

RESUMEN

BACKGROUND: Nationwide population-based information on the prevalence of multiple sclerosis (MS) in Germany has so far not been available. In this study the prevalence of MS was determined with the help of the claims data of the health insurance funds underlying the morbidity-based risk adjustment scheme (M-RSA). MATERIAL AND METHODS: Health insurance funds reported inpatient and outpatient diagnoses, outpatient prescriptions, costs and enrolment data for all persons insured in the German statutory health insurance (SHI). The data reported for 2010 form the basis of this study which collated data on the 12-month prevalence, prevalence related to age and gender, drug therapy, regional distribution pattern, combinations of diagnoses and hospitalization. RESULTS: Nearly 200,000 people insured in the SHI have been diagnosed with MS. Hence, the prevalence seems to be considerably higher than was previously assumed. In addition, a slight west-east gradient was apparent. On average 49 % of all MS patients (with a slight east-west gradient) received MS-specific inpatient drug therapy. Insured patients living in the east received on average 30 daily doses per year less than patients living in the western part. CONCLUSION: For the first time MS prevalence has been determined nationwide for Germany with the help of SHI data. It appears that previously applied methods have underestimated the prevalence. The regional differences found with respect to prevalence and drug therapy need further clarification. The data underlying the M-RSA do not allow more causal research.

Asunto(s)

Prescripciones de Medicamentos/estadística & datos numéricos , Inmunosupresores/uso terapéutico , Reembolso de Seguro de Salud/estadística & datos numéricos , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/epidemiología , Programas Nacionales de Salud/estadística & datos numéricos , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Geografía Médica , Alemania/epidemiología , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Distribución por Sexo , Análisis Espacio-Temporal , Adulto Joven

RESUMEN

Laboratory studies were carried out to cast light on differences in density responses among collembolan species to copper (Cu)-polluted environments. In a recolonisation experiment, mesofauna originating from a copper (Cupolluted arable field were allowed to colonise defaunated Cu-contaminated and uncontaminated soil cores for 3 months. The abundances of Pseudosinella alba and gamasid mites were higher in the uncontaminated soil, whereas the majority of other collembolans tended to be more abundant in the Cu-enriched soil. Behavioural experiments were conducted to test the ability of single Collembola species to distinguish between filter paper and food soaked in water, Cu, and calcium (Ca) solutions. Onychiurus armatus avoided both Cu and Ca, whereas Folsomia quadrioculata and Folsomia manolachei showed a significant preference for Cu. Isotomurus palustris was not able to distinguish between Cu and water. The results are compared and discussed with regard to other studies on the occurrence and behaviour of Collembola in Cu-contaminated environments. We suggest that microsite selection according to preference or avoidance of high salinity of pore water may partly explain the community structure of Collembola in Cu-polluted soils which are characterised by an increase of euedaphic species. More studies have to be carried out to generalise this concept and to explore to what extent reduced predation by gamasid mites contribute to the success of certain Collembola in Cu-contaminated sites.

RESUMEN

Variable clinical course has been reported with the acquisition of Burkholderia cepacia in patients who have cystic fibrosis (CF). We hypothesized that the perceived worsening with B. cepacia may reflect the underlying severity of pulmonary disease at the time of acquisition. To test this hypothesis, we matched CF patients colonized with B. cepacia with CF patients not colonized with the organism. Two-year pre- and postacquisition data and long-term data were compared. Patients were matched for gender, age (+/- 1 yr), height (+/- 5 cm), weight (+/- 8 kg), percent predicted forced expiratory volume in one second (% pred FEV(1)) (+/- 10%), and pancreatic sufficiency status. Differences in rates of change pre- and postacquisition for FEV(1), FVC, weight, and frequency of intravenous courses were compared within pairs with the Wilcoxon signed rank test. Two-year and long-term survival was compared within pairs with the McNemar test. No significant differences were observed in mean annual rates of change in weight (0.33 and -0.28 kg/yr), % pred FEV(1) (-0.36 and -1.74%/yr), and percent predicted forced vital capacity (% pred FVC) (-3.80 and -2.32%/yr) between B. cepacia and control pairs in 2-yr and long-term postacquisition interval, respectively. Similar rates of change were noted for pre- to postacquisition intervals within pairs for weight (0.17 kg/yr), % pred FEV(1) (-0.16%/yr), % pred FVC (5.02 %/yr). There was a significantly higher rate of intravenous antibiotic courses in B. cepacia cases in the 2-yr and long-term postacquisition interval. Higher mortality was observed in the B. cepacia cases in the long term (p < 0.05). We conclude that colonization with B. cepacia does not necessarily adversely affect pulmonary status, but is associated with reduced long term survival. Whereas previous associations may be attributed to a propensity to colonize those who had more advanced disease, specific strain types of B. cepacia may have enhanced pathogenicity.

Asunto(s)

Infecciones por Burkholderia/complicaciones , Burkholderia cepacia , Fibrosis Quística/complicaciones , Adolescente , Adulto , Infecciones por Burkholderia/tratamiento farmacológico , Infecciones por Burkholderia/fisiopatología , Niño , Fibrosis Quística/fisiopatología , Femenino , Volumen Espiratorio Forzado , Humanos , Masculino , Capacidad Vital

RESUMEN

This study reviews the clinical outcome of knee arthroplasty (Microloc, Johnson & Johnson Orthopedics, Norderstedt, Germany) with a resurfacing metal-backed patellar component. Thirty patients were available for clinical and radiographic reexamination with follow-up periods of 36 and 72 months. There were 21 women and 9 men, with an average age of 71.1 years. At the follow-up examination, seven patients demonstrated a metallic friction noise, and three had only mild crepitation at the patellofemoral joint level. In the group complaining of knee pain, the average knee score dropped from 76.9 +/- 9.9 at 36 months to 44.7 +/- 15.3 (P < .05) prior to revision surgery on average at 66 months. The function score dropped during the same time from 72.0 +/- 19.7 to 53.5 +/- 14.9. In contrast, the pain-free group did not demonstrate any significant changes in either knee or function score. Radiographic evaluation showed a patellar tilt of 8.1 degrees +/- 4.0 degrees in the group complaining of pain, compared with 2.5 degrees +/- 2.3 degrees in the pain-free patient collective. All 10 patients complaining of pain and increasing disability underwent revision surgery. At the time of surgery, an obvious polyethylene particle-induced synovitis was found, and in 7 patients it was associated with a metallosis. One of the main reasons for failure of metal-backed polyethylene components is thought to be the undue high stresses forced onto the insert. High loading of only a small fraction of the surface will lead to increased polyethylene creep and particle formation, resulting in synovitis and finally metallosis. Early revision seems to be the best solution to prevent progressive destruction of the entire joint. Previously reported results on metal-backed patellar components show a failure rate of 8.4% after 12 to 24 months. In this study, this rate had already increased to 33.3% after 6 years. One might therefore speculate that at 10 years, revision surgery might become necessary in more than 50% of the surviving patients with this type of implant.

Asunto(s)

Prótesis de la Rodilla , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Metales , Persona de Mediana Edad , Diseño de Prótesis , Reoperación , Estudios Retrospectivos , Resultado del Tratamiento

RESUMEN

Abnormalities of both the spontaneous and the stimulated release of growth hormone (GH) have been described in patients with endogenous depression. In this study, six unmedicated male patients with endogenous depression (ICD 296.1/3) were compared with six age-matched healthy men. Levels of GH were determined at 15-minute intervals over 26 hours. A combined releasing hormone test was performed during the last 2 hours of blood sampling. The 24-hour profile of GH secretion was significantly lower in the depressed patients than in the healthy control subjects due to a significantly diminished sleep-related GH secretion. GH stimulation following releasing hormones was lower in the depressed patients than in healthy subjects. Hypersecretion of GH before the stimulation test might therefore not explain the blunted GH response to stimulation that has been observed in depressive patients.

Asunto(s)

Ritmo Circadiano/fisiología , Trastorno Depresivo/sangre , Hormona del Crecimiento/sangre , Adulto , Hormona Liberadora de Corticotropina , Trastorno Depresivo/diagnóstico , Trastorno Depresivo/psicología , Hormona Liberadora de Gonadotropina , Hormona Liberadora de Hormona del Crecimiento , Humanos , Masculino , Polisomnografía , Valores de Referencia , Hormona Liberadora de Tirotropina

RESUMEN

We derive a far-field diffraction integral by (vector) electromagnetic theory; the result differs from the (scalar) Rayleigh-Sommerfeld or Kirchhoff result in that it depends on polarization. For unpolarized light, we derive a factor (1 + cos(2) theta)((1/2))/ radical2 that replaces the usual obliquity factor. Omitting this factor can cause an error of the same order as the measurement uncertainty in determining the mode-field diameter of a single-mode fiber from far-field data.

RESUMEN

Simple spherical-wave expansions of the continuous-wave fields of a circular piston radiator in a rigid baffle are derived. These expansions are valid throughout the illuminated half-space and are useful for efficient numerical computation in the near-field region. Multipole coefficients are given by closed-form expressions which can be evaluated recursively.

Asunto(s)

Acústica , Algoritmos , Campos Electromagnéticos , Humanos

RESUMEN

Herein is reported a fifth case of malignant pheochromocytoma of the urinary bladder. Pheochromocytoma represents only 0.4 per cent of bladder tumors with 5 to 10 per cent being malignant. A review of the 4 previously reported cases plus our own suggest that iliac-hypogastric lymphadenectomy should be considered in all cases of pheochromocytoma of the bladder. Early establishment of the malignant potential of these tumors coupled with aggressive surgical treatment improves prognosis.

Asunto(s)

Feocromocitoma/cirugía , Neoplasias de la Vejiga Urinaria/cirugía , Humanos , Escisión del Ganglio Linfático , Masculino , Persona de Mediana Edad , Feocromocitoma/patología , Pronóstico , Neoplasias de la Vejiga Urinaria/patología

RESUMEN

Myocardial cells from newborn rats were held in a spinner type culture for 2 days and then explanted into culture flasks. Three main cell types were observed: single multipolar cells of embryonic type, cell aggregates containing 10 to 50 connected cells, and bipolar cells retaining some adult characteristics. Except for the latter, up to 95% of intact cells settled and were beating 6 hours after explantation. The percentage of fibroblast-like cells was drastically reduced when compared with conventional cultures. Cell debris could be removed 2 hours after explantation by changing the culture medium, or more effectively by a density step centrifugation using Lymphoprep or Lymphoprep-Ficoll mixtures.

Asunto(s)

Células Cultivadas/citología , Miocardio/citología , Animales , Adhesión Celular , Agregación Celular , Diferenciación Celular , Centrifugación por Gradiente de Densidad , Técnicas Citológicas , Mitosis , Contracción Miocárdica , Ratas

RESUMEN

The effect of 3',4'-dihydroxy-alpha-methylpropiophenone (U-0521) on the rate of spontaneously contracting cultured rat heart cells and right atria of rats and kittens was investigated. The action of U-0521 on the cellular content of cyclic AMP and on the adenylyl cyclase of heart membrane particels was also studied. 1. U-0521 caused positive chronotropic effects on single cultured heart cells and right atria of the rat. U-0521 was about 10(5) times less potent than (--)-isoprenaline. The maximum effect of U-0521 was smaller than the maximum effect of (--)-isoprenaline. A small positive chronotropic effect of U-0521 was also observed on kitten atria. 2. The beta-adrenoceptor blocker (--)-bupranolol antagonized the positive chronotropic effects of U-0521 to the same extent as the effects of (--)-isoprenaline on single cells and atria of the rat. The effects of both U-0521 and (--)-isoprenaline appear therefore mediated through the same beta-adrenoceptors. The positive chronotropic effects of U-0521 on kitten atria were also blocked by (--)-bupranolol. 3. Up to 0.1 mM U-0521 did not block the effects of (--)-isoprenaline on rat atria, not even in the presence of corticosterone or hydrocortisone. 4. 1 min incubations with equieffective (increase in cellular beating rate) concentrations of U-0521 (0.1 mM) and (--)-isoprenaline (1 nM) caused a significant increase in the cellular content of cAMP; this effect of both drugs was antagonized by 10 nM (--)-bupranolol. 5. 0.1--3.3 mM U-0521 did not stimulate the adenylyl cyclase of cell-free membrane particles of kitten ventricles. The cyclase was depressed by 10 mM U-0521. 3.3 mM U-0521 caused a 20% decrease of the maximum cyclase-stimulating effect of (--)-isoprenaline and a 1.6-fold increase of its apparent Km. 6. The results with U-0521 suggest that beta-adrenoceptors can be activated by agonists devoid of nitrogen. However, the affinity of U-0521 for the beta-adrenoceptor is very low (KU-0521 approximately 5.5 mM). The concentration of U-0521 (0.1 mM) causing maximal increases in beating rate of cultured cells probably occupies less than 7% of the available beta-adrenoceptors.

Asunto(s)

Frecuencia Cardíaca/efectos de los fármacos , Propiofenonas/farmacología , Receptores Adrenérgicos beta/efectos de los fármacos , Receptores Adrenérgicos/efectos de los fármacos , Adenilil Ciclasas/metabolismo , Antagonistas Adrenérgicos beta/farmacología , Animales , Gatos , Membrana Celular/efectos de los fármacos , Membrana Celular/enzimología , Corticosterona/farmacología , AMP Cíclico/metabolismo , Interacciones Farmacológicas , Femenino , Corazón/efectos de los fármacos , Corazón/inervación , Hidrocortisona/farmacología , Técnicas In Vitro , Isoproterenol/farmacología , Ligandos , Masculino , Miocardio/metabolismo , Miocardio/ultraestructura , Nitrógeno , Propanolaminas/farmacología , Ratas , Estimulación Química , Relación Estructura-Actividad

RESUMEN

Heart cells from newborn rats and kittens were cultured. In both species the rate of pacemaker activity of single, cultured cells was increased by low concentrations of catecholamines. Tthe beta-adrenoceptor blocker (minus)-KL255 antagonized competitively the effects of both, (minus)-noradrenaline and (minus)-isoprenaline. A mean equilibrium constant of 3.6 times 10-10M between (minus)-KL255 and beta-adrenoceptors of single cells was estimated.

Asunto(s)

Antagonistas Adrenérgicos beta/farmacología , Propanolaminas/farmacología , Receptores Adrenérgicos , Nodo Sinoatrial/efectos de los fármacos , Antagonistas Adrenérgicos beta/metabolismo , Animales , Animales Recién Nacidos , Unión Competitiva , Butilaminas/farmacología , Gatos , Células Cultivadas , Isoproterenol/antagonistas & inhibidores , Cinética , Microscopía de Contraste de Fase , Miocardio/citología , Norepinefrina/antagonistas & inhibidores , Éteres Fenílicos/farmacología , Propanolaminas/metabolismo , Ratas , Nodo Sinoatrial/citología

Asunto(s)

Aborto Espontáneo/inducido químicamente , Halotano/efectos adversos , Animales , Femenino , Óxido Nitroso/farmacología , Oxígeno/farmacología , Embarazo , Ratas

Asunto(s)

Anomalías Inducidas por Medicamentos/etiología , Feto/efectos de los fármacos , Halotano/efectos adversos , Aborto Espontáneo/inducido químicamente , Animales , Femenino , Reabsorción del Feto/inducido químicamente , Óxido Nitroso/farmacología , Oxígeno/farmacología , Embarazo , Ratas , Costillas/anomalías , Columna Vertebral/anomalías

Asunto(s)

Amidas/farmacología , Analgésicos/farmacología , Atención/efectos de los fármacos , Electroencefalografía , Etanol/farmacología , Prometazina/farmacología , Propionatos/farmacología , Aspirina/farmacología , Cafeína/farmacología , Ensayos Clínicos como Asunto , Codeína/farmacología , Sinergismo Farmacológico , Electrooculografía , Movimientos Oculares/efectos de los fármacos , Femenino , Fumaratos/farmacología , Humanos , Masculino , Fenacetina/farmacología , Fenobarbital/farmacología , Piperidinas/farmacología , Placebos , Piridinas/farmacología

RESUMEN

PIP: The abortifacient effects of halothane and nitrous oxide were studie d in 505 adult female rats. Anesthesia with a mixture of nitrous oxide, oxygen, and halothane in the 6th-10th week of pregnancy resulted in spontaneous abortion in 44% of the animals; the incidence was 50.5% in the 7th-9th week. The number of abortions was directly proportional to the amount of halothane administered. Nitrous oxide was followed by abortion in 13%, an incidence within the normal limits for spontaneous a bortion.^ieng

Asunto(s)

Aborto Espontáneo/inducido químicamente , Halotano/efectos adversos , Animales , Femenino , Edad Gestacional , Halotano/administración & dosificación , Óxido Nitroso/administración & dosificación , Óxido Nitroso/efectos adversos , Oxígeno/administración & dosificación , Embarazo , Preñez , Ratas , Factores de Tiempo