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1.
Opt Express ; 21(25): 31098-104, 2013 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-24514684

RESUMEN

We present a diode incorporating a large number (12) of GaAs quantum wells that emits light from exciton-polariton states at room temperature. A reversely biased tunnel junction is placed in the cavity region to improve current injection into the device. Electroluminescence studies reveal two polariton branches which are spectrally separated by a Rabi splitting of 6.5 meV. We observe an anticrossing of the two branches when the temperature is lowered below room temperature as well as a Stark shift of both branches in a bias dependent photoluminescence measurement.


Asunto(s)
Arsenicales/química , Galio/química , Iluminación/instrumentación , Puntos Cuánticos , Semiconductores , Diseño de Equipo , Análisis de Falla de Equipo , Integración de Sistemas , Temperatura
2.
Eur Arch Otorhinolaryngol ; 269(7): 1755-8, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22045302

RESUMEN

Since inner ear hair cells are mechano-electric transducers the control of hydrostatic pressure in the inner ear is crucial. Most studies analyzing dynamics and regulation of inner ear hydrostatic pressure performed pressure measurements in the cochlea. The present study is the first one reporting about absolute hydrostatic pressure values in the labyrinth. Hydrostatic pressure of the endolymphatic system was recorded in all three semicircular canals. Mean pressure values were 4.06 cmH(2)O ± 0.61 in the posterior, 3.36 cmH(2)O ± 0.94 in the anterior and 3.85 cmH(2)O ± 1.38 in the lateral semicircular canal. Overall hydrostatic pressure in the vestibular organ was 3.76 cmH(2)O ± 0.36. Endolymphatic hydrostatic pressure in all three semicircular canals is the same (p = 0.310). With regard to known endolymphatic pressure values in the cochlea from past studies vestibular pressure values are comparable to cochlear values. Until now it is not known whether the reuniens duct and the Bast's valve which are the narrowest passages in the endolymphatic system are open or closed. Present data show that most likely the endolymphatic system is a functionally open entity.


Asunto(s)
Transferencias de Fluidos Corporales/fisiología , Presión Hidrostática , Líquidos Laberínticos/fisiología , Vestíbulo del Laberinto/fisiología , Animales , Cóclea/fisiología , Cobayas , Hidrodinámica , Valores de Referencia , Canales Semicirculares/fisiología
3.
PeerJ ; 8: e8400, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32002331

RESUMEN

An isolated hyomandibula from a lower Toarcian carbonate concretion of the Ahrensburg erratics assemblage (Schleswig-Holstein, northern Germany) represents the first record of a chondrosteid fish from the Lower Jurassic of the southwestern Baltic realm. Except for its smaller size, the specimen is morphologically indistinguishable from corresponding elements of Gyrosteus mirabilis from the Toarcian of Yorkshire, England. This find, which probably originates from the western Baltic basin between Bornholm Island (Denmark) and northeastern Germany, markedly expands the known range of this chondrosteid taxon across the northern part of the strait connecting the Boreal Sea with the Tethys Ocean during the Early Jurassic. For the first time the extension of the paleogeographic range of a chondrosteid species beyond its type area is documented, which can contribute to future studies of vertebrate faunal provincialism during the Lower Jurassic in Europe.

5.
Zootaxa ; 4154(2): 197-200, 2016 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-27615836

RESUMEN

Two genus-group names of flat-worms-Leptocleidus Mueller, 1936 and Macrorhynchus von Graff, 1882-are junior homonyms that are preoccupied by fossil diapsid reptile genera-Leptocleidus Andrews, 1922, and Macrorhynchus Dunker, 1843-and an extant teleost fish genus-Macrorhynchus [Gmelin, 1801] ex La Cépède, 1800. These are replaced by nomina nova (Pharyngodytes nom. nov.; Graffiellus nom. nov.). Macrorhynchus [Gmelin, 1801] is an objective senior synonym of Macrorhyncus Dumeríl, 1805 ex La Cépède, 1800 (syn. nov.), and a senior homonym of Macrorhynchus Dunker, 1843, and Macrorhynchus von Graff, 1882.


Asunto(s)
Platelmintos/clasificación , Animales , Fósiles/historia , Historia del Siglo XIX , Historia del Siglo XX , Terminología como Asunto
6.
PeerJ ; 4: e2813, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28028478

RESUMEN

The holotype of Brancasaurus brancai is one of the most historically famous and anatomically complete Early Cretaceous plesiosaurian fossils. It derived from the Gerdemann & Co. brickworks clay pit near Gronau (Westfalen) in North Rhine-Westphalia, northwestern Germany. Stratigraphically this locality formed part of the classic European "Wealden facies," but is now more formally attributed to the upper-most strata of the Bückeberg Group (upper Berriasian). Since its initial description in 1914, the type skeleton of B. brancai has suffered damage both during, and after WWII. Sadly, these mishaps have resulted in the loss of substantial information, in particular many structures of the cranium and limb girdles, which are today only evidenced from published text and/or illustrations. This non-confirmable data has, however, proven crucial for determining the relationships of B. brancai within Plesiosauria: either as an early long-necked elasmosaurid, or a member of the controversial Early Cretaceous leptocleidid radiation. To evaluate these competing hypotheses and compile an updated osteological compendium, we undertook a comprehensive examination of the holotype as it is now preserved, and also assessed other Bückeberg Group plesiosaurian fossils to establish a morphological hypodigm. Phylogenetic simulations using the most species-rich datasets of Early Cretaceous plesiosaurians incorporating revised scores for B. brancai, together with a second recently named Bückeberg Group plesiosaurian Gronausaurus wegneri (Hampe, 2013), demonstrated that referral of these taxa to Leptocleididae was not unanimous, and that the topological stability of this clade is tenuous. In addition, the trait combinations manifested by B. brancai and G. wegneri were virtually identical. We therefore conclude that these monotypic individuals are ontogenetic morphs and G. wegneri is a junior synonym of B. brancai. Finally, anomalies detected in the diagnostic features for other "Wealden" plesiosaurians have prompted reconsiderations of interspecies homology versus intraspecific variability. We therefore propose that the still unresolved taxonomy of B. brancai should emphasize only those character states evident in the examinable fossil material, and specifically accommodate for growth-related modifications delimited via osteologically mature referred specimens.

7.
Eur J Paediatr Neurol ; 20(1): 147-51, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26387070

RESUMEN

OBJECTIVE: Mutations in the CDKL5 gene cause an early-onset epileptic encephalopathy. To date, little is known about effective antiepileptic treatment in this disorder. METHOD: Accordingly, the aim of this retrospective study was to explore the role of different antiepileptic drugs (AEDs) and the ketogenic diet (KD) in the treatment of this rare genetic disorder. We evaluated the efficacy in 39 patients with CDKL5 mutations at 3, 6 and 12 months after the introduction of each treatment. One patient was lost to follow-up after 6 and 12 months. RESULTS: The responder rate (>50% reduction in seizure frequency) to at least one AED or KD was 69% (27/39) after 3 months, 45% (17/38) after 6 months and 24% (9/38) after 12 months. The highest rate of seizure reduction after 3 months was reported for FBM (3/3), VGB (8/25), CLB (4/17), VPA (7/34), steroids (5/26), LTG (5/23) and ZNS (2/11). Twelve patients (31%) experienced a seizure aggravation to at least one AED. Most patients showed some but only initial response to various AEDs with different modes of actions. SIGNIFICANCE: Considering both age-related and spontaneous fluctuation in seizure frequency and the unknown impact of many AEDs or KD on cognition, our data may help defining realistic treatment goals and avoiding overtreatment in patients with CDKL5 mutations. There is a strong need to develop new treatment strategies for patients with this rare mutation.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Dieta Cetogénica , Epilepsia/dietoterapia , Epilepsia/tratamiento farmacológico , Adulto , Epilepsia/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación , Proteínas Serina-Treonina Quinasas/genética , Estudios Retrospectivos , Convulsiones/prevención & control , Resultado del Tratamiento , Adulto Joven
8.
Circulation ; 103(3): 351-6, 2001 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-11157684

RESUMEN

BACKGROUND: Recovery of the intracellular bacterium Chlamydia pneumoniae from atherosclerotic plaques has initiated large studies on antimicrobial therapy in coronary artery disease. The basic concept that antibiotic therapy may eliminate and prevent vascular infection was evaluated in vitro and in vivo by examining the antibiotic susceptibility of C pneumoniae in circulating human monocytes, which are thought to transport chlamydiae from the respiratory tract to the vascular wall. METHODS AND RESULTS: Blood monocytes (CD14+) from 2 healthy volunteers were obtained before and after oral treatment with azithromycin or rifampin and then inoculated with a vascular C pneumoniae strain and continuously cultured in the presence of the respective antibiotic. Progress of infection and chlamydial viability was assessed by immunogold-labeling and detection of C pneumoniae-specific mRNA transcripts. Circulating monocytes from patients undergoing treatment with experimental azithromycin for coronary artery disease were examined for C pneumoniae infection by cell culture. Antibiotics did not inhibit chlamydial growth within monocytes. Electron microscopy showed development of chlamydial inclusion bodies. Reverse transcription-polymerase chain reaction demonstrated continuous synthesis of chlamydial mRNA for 10 days without lysis of the monocytes. The in vivo presence of viable pathogen not eliminated by azithromycin was shown by cultural recovery of C pneumoniae from the circulating monocytes of 2 patients with coronary artery disease. CONCLUSIONS: C pneumoniae uses monocytes as a transport system for systemic dissemination and enters a persistent state not covered by an otherwise effective antichlamydial treatment. Prevention of vascular infection by antichlamydial treatment may be problematic: circulating monocytes carrying a pathogen with reduced antimicrobial susceptibility might initiate reinfection or promote atherosclerosis by the release of proinflammatory mediators.


Asunto(s)
Antibacterianos/farmacología , Azitromicina/farmacología , Chlamydophila pneumoniae/efectos de los fármacos , Enfermedad Coronaria/tratamiento farmacológico , Monocitos/microbiología , Rifampin/farmacología , Anciano , Antibacterianos/uso terapéutico , Azitromicina/uso terapéutico , Células Cultivadas , Chlamydophila pneumoniae/genética , Chlamydophila pneumoniae/patogenicidad , Chlamydophila pneumoniae/ultraestructura , Enfermedad Coronaria/sangre , Enfermedad Coronaria/microbiología , Humanos , Receptores de Lipopolisacáridos/inmunología , Masculino , Pruebas de Sensibilidad Microbiana , Microscopía Inmunoelectrónica , Persona de Mediana Edad , Monocitos/efectos de los fármacos , Monocitos/inmunología , ARN Mensajero/análisis , ARN Mensajero/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rifampin/uso terapéutico , Factores de Tiempo
9.
J Neural Transm Suppl ; 44: 97-109, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7897403

RESUMEN

Examples are given for assessing parameters for motor activity learning and memory. By using the method of the open field the authors could verify that motor activity decreases with age and that it underlies obviously endogenous rhythms which undergo age dependent alterations (e.g. diminution of the amplitude). From the results of an investigation on the influence of ageing and stress on learning ability and memory of the rat the authors draw the following conclusions: Learning ability declines with advancing age. The effect of ageing on memory could not be clearly shown. The effect of the stressors used (crowding and noise) seems to depend on the season of the year (circannual biorhythm).


Asunto(s)
Envejecimiento/psicología , Aprendizaje , Memoria , Actividad Motora , Animales , Ritmo Circadiano , Oscuridad , Luz , Masculino , Aprendizaje por Laberinto , Probabilidad , Psicometría , Ratas , Ratas Sprague-Dawley , Valores de Referencia , Refuerzo en Psicología
10.
Avian Dis ; 46(2): 485-92, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12061663

RESUMEN

In this paper we report on an outbreak of reovirus, herpesvirus (Pacheco disease), and/or mycosis infection (Aspergillus spp. and Zygomyces spp.) affecting a batch of young African grey parrots (Psittacus erithacus), with 80% morbidity and 30% mortality. Study material was taken from five birds (four dead and one euthanatized) with a range of clinical symptoms (depression, diarrhea, respiratory symptoms). Diagnosis was confirmed by immunohistochemical detection of avian reovirus, electron microscopy, and virus isolation. Viral antigen of reovirus was detected mainly in large mononuclear cells in the bursa of Fabricius and the spleen, pancreas epithelial cells, and circulating cells; lymphoid organs displayed the largest number of immunopositive cells and severe lymphocyte depletion. Bacteriologic study was negative. Reovirus infection was common in all birds studied, whereas Pacheco disease and mycosis were found in only some, suggesting that reovirus could be the initial cause triggering the outbreak and facilitating infection by other agents and their swift spread through the batch.


Asunto(s)
Enfermedades de las Aves/virología , Brotes de Enfermedades/veterinaria , Loros , Infecciones por Reoviridae/veterinaria , Reoviridae/aislamiento & purificación , Animales , Antígenos Virales/análisis , Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/mortalidad , Enfermedades de las Aves/patología , Guinea/epidemiología , Infecciones por Herpesviridae/complicaciones , Infecciones por Herpesviridae/patología , Infecciones por Herpesviridae/veterinaria , Inmunohistoquímica/veterinaria , Microscopía Electrónica/veterinaria , Micosis/complicaciones , Micosis/patología , Micosis/veterinaria , Reoviridae/inmunología , Reoviridae/ultraestructura , Infecciones por Reoviridae/complicaciones , Infecciones por Reoviridae/epidemiología , Infecciones por Reoviridae/patología
11.
Cranio ; 9(2): 145-51, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1802423

RESUMEN

The authors imaged 20 temporomandibular joints (TMJs) in 20 patients with high field surface coil magnetic resonance imaging, to compare the accuracy and the clinical utility of thin section partial flip angle (PFA) three dimensional (3D) volume acquisitions with T1-weighted images (T1WI), spin echo, multiecho, long TR/short and long TE images, PFA gradient recalled acquisition in the steady state (GRASS) images in the diagnosis of internal derangement of the TMJ. Pathological conditions demonstrated on imaging studies included disk derangement, joint effusion, and osteocartilaginous lesions, such as degenerative arthritis, osteoporosis, osteochondritis dissecans and early avascular necrosis of the mandibular condyle.


Asunto(s)
Trastornos de la Articulación Temporomandibular/patología , Humanos , Imagen por Resonancia Magnética/métodos , Articulación Temporomandibular/anatomía & histología
12.
PLoS One ; 8(4): e60571, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23560099

RESUMEN

A fragmentary cervico-pectoral lateral spine and partial humerus of an ankylosaur from the Early Cretaceous (early Valanginian) of Gronau in Westfalen, northwestern Germany, are described. The spine shows closest morphological similarities to the characteristic cervical and pectoral spines of Hylaeosaurus armatus from the late Valanginian of England. An extensive comparison of distal humeri among thyreophoran dinosaurs supports systematic differences in the morphology of the distal condyli between Ankylosauria and Stegosauria and a referral of the Gronau specimen to the former. The humerus fragment indicates a rather small individual, probably in the size range of H. armatus, and both specimens are determined herein as ?Hylaeosaurus sp.. A short overview of other purported ankylosaur material from the Berriasian-Valanginian of northwest Germany shows that, aside from the material described herein, only tracks can be attributed to this clade with confidence at present.


Asunto(s)
Dinosaurios/anatomía & histología , Fósiles , Húmero/anatomía & histología , Paleontología , Columna Vertebral/anatomía & histología , Animales , Dinosaurios/clasificación , Alemania , Filogeografía
13.
PLoS One ; 6(10): e25693, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22022431

RESUMEN

BACKGROUND: Archosaurs (birds, crocodilians and their extinct relatives including dinosaurs) dominated Mesozoic continental ecosystems from the Late Triassic onwards, and still form a major component of modern ecosystems (>10,000 species). The earliest diverse archosaur faunal assemblages are known from the Middle Triassic (c. 244 Ma), implying that the archosaur radiation began in the Early Triassic (252.3-247.2 Ma). Understanding of this radiation is currently limited by the poor early fossil record of the group in terms of skeletal remains. METHODOLOGY/PRINCIPAL FINDINGS: We redescribe the anatomy and stratigraphic position of the type specimen of Ctenosauriscus koeneni (Huene), a sail-backed reptile from the Early Triassic (late Olenekian) Solling Formation of northern Germany that potentially represents the oldest known archosaur. We critically discuss previous biomechanical work on the 'sail' of Ctenosauriscus, which is formed by a series of elongated neural spines. In addition, we describe Ctenosauriscus-like postcranial material from the earliest Middle Triassic (early Anisian) Röt Formation of Waldhaus, southwestern Germany. Finally, we review the spatial and temporal distribution of the earliest archosaur fossils and their implications for understanding the dynamics of the archosaur radiation. CONCLUSIONS/SIGNIFICANCE: Comprehensive numerical phylogenetic analyses demonstrate that both Ctenosauriscus and the Waldhaus taxon are members of a monophyletic grouping of poposauroid archosaurs, Ctenosauriscidae, characterised by greatly elongated neural spines in the posterior cervical to anterior caudal vertebrae. The earliest archosaurs, including Ctenosauriscus, appear in the body fossil record just prior to the Olenekian/Anisian boundary (c. 248 Ma), less than 5 million years after the Permian-Triassic mass extinction. These earliest archosaur assemblages are dominated by ctenosauriscids, which were broadly distributed across northern Pangea and which appear to have been the first global radiation of archosaurs.


Asunto(s)
Evolución Biológica , Dinosaurios/anatomía & histología , Filogeografía , Animales , Dinosaurios/genética , Fósiles , Alemania , Paleontología , Filogenia , Factores de Tiempo
19.
Basic Res Cardiol ; 95 Suppl 1: I59-64, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11192355

RESUMEN

It is well accepted that coronary artery disease is linked to an inflammatory process. It is unknown which agents may cause or accelerate coronary artery disease. An inflammation of the vessel wall may be caused by a number of mechanisms such as accumulation of glycosylated proteins in diabetic patients, oxidised LDL in patients with hypercholesterolemia or infectious agents. Among the possible infectious agents Chlamydia pneumoniae is the most likely microorganism involved in atherosclerosis. The arguments in favour of Chlamydia pneumoniae result from seroepidemiologic studies and from detection of chlamydial DNA in atherosclerotic plaques by polymerase chain reaction (PCR). In addition this microorganism is the only one that could be isolated from atherosclerotic tissue. This review summarises the present understanding of the role of an inflammatory process in the development or progression of coronary artery disease.


Asunto(s)
Enfermedad Coronaria/etiología , Enfermedad Coronaria/microbiología , Infecciones/complicaciones , Vasculitis/complicaciones , Proteínas de Fase Aguda/metabolismo , Animales , Infecciones Bacterianas , Enfermedad Coronaria/fisiopatología , Enfermedad Coronaria/terapia , Progresión de la Enfermedad , Humanos , Vasculitis/microbiología , Virosis
20.
Genes Immun ; 5(5): 435-8, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15175649

RESUMEN

Chlamydia pneumoniae uses peripheral blood monocytes (PBMC) for systemic dissemination and has been linked to atherogenesis by inflammation mediated via TLR2/4 and CD14. We found 12.8% of 610 coronary artery disease (CAD) patients of Central European background to be chronically infected with C. pneumoniae based on the repeated detection of chlamydial DNA in PBMC. Among those the -159C>T CD14 promoter polymorphism was more frequent (OR 1.7, 95% CI 1.08-2.65, P=0.0224) than among C. pneumoniae-negative subjects matched for age and gender. The Arg753Gln TLR2 and Asp299Gly TLR4 polymorphisms were not related to chlamydial infection. Susceptibility for chronic chlamydial infection of PBMC in CAD patients appears associated with the CD14-159C>T promoter polymorphism encoding for enhanced CD14 expression.


Asunto(s)
Infecciones por Chlamydia/genética , Chlamydophila pneumoniae , Receptores de Lipopolisacáridos/genética , Monocitos/microbiología , Polimorfismo Genético , Regiones Promotoras Genéticas/genética , Anticuerpos Antibacterianos/biosíntesis , Anticuerpos Antibacterianos/genética , Infecciones por Chlamydia/metabolismo , Infecciones por Chlamydia/microbiología , Frecuencia de los Genes/genética , Predisposición Genética a la Enfermedad/genética , Humanos , Monocitos/metabolismo
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