RESUMEN
Intraspecific acoustic communication requires filtering processes and feature detectors in the auditory pathway of the receiver for the recognition of species-specific signals. Insects like acoustically communicating crickets allow describing and analysing the mechanisms underlying auditory processing at the behavioral and neural level. Female crickets approach male calling song, their phonotactic behavior is tuned to the characteristic features of the song, such as the carrier frequency and the temporal pattern of sound pulses. Data from behavioral experiments and from neural recordings at different stages of processing in the auditory pathway lead to a concept of serially arranged filtering mechanisms. These encompass a filter for the carrier frequency at the level of the hearing organ, and the pulse duration through phasic onset responses of afferents and reciprocal inhibition of thoracic interneurons. Further, processing by a delay line and coincidence detector circuit in the brain leads to feature detecting neurons that specifically respond to the species-specific pulse rate, and match the characteristics of the phonotactic response. This same circuit may also control the response to the species-specific chirp pattern. Based on these serial filters and the feature detecting mechanism, female phonotactic behavior is shaped and tuned to the characteristic properties of male calling song.
RESUMEN
INTRODUCTION: The aim of this study was to develop a clinical-grade, automated, multiplex system for the differential diagnosis and molecular stratification of rheumatoid arthritis (RA). METHODS: We profiled autoantibodies, cytokines, and bone-turnover products in sera from 120 patients with a diagnosis of RA of < 6 months' duration, as well as in sera from 27 patients with ankylosing spondylitis, 28 patients with psoriatic arthritis, and 25 healthy individuals. We used a commercial bead assay to measure cytokine levels and developed an array assay based on novel multiplex technology (Immunological Multi-Parameter Chip Technology) to evaluate autoantibody reactivities and bone-turnover markers. Data were analyzed by Significance Analysis of Microarrays and hierarchical clustering software. RESULTS: We developed a highly reproducible, automated, multiplex biomarker assay that can reliably distinguish between RA patients and healthy individuals or patients with other inflammatory arthritides. Identification of distinct biomarker signatures enabled molecular stratification of early-stage RA into clinically relevant subtypes. In this initial study, multiplex measurement of a subset of the differentiating biomarkers provided high sensitivity and specificity in the diagnostic discrimination of RA: Use of 3 biomarkers yielded a sensitivity of 84.2% and a specificity of 93.8%, and use of 4 biomarkers a sensitivity of 59.2% and a specificity of 96.3%. CONCLUSIONS: The multiplex biomarker assay described herein has the potential to diagnose RA with greater sensitivity and specificity than do current clinical tests. Its ability to stratify RA patients in an automated and reproducible manner paves the way for the development of assays that can guide RA therapy.
Asunto(s)
Artritis Reumatoide/diagnóstico , Artritis Reumatoide/inmunología , Inmunoensayo , Dispositivos Laboratorio en un Chip/normas , Proteómica , Antígenos/análisis , Antígenos/sangre , Artritis Psoriásica/diagnóstico , Artritis Psoriásica/inmunología , Biomarcadores/análisis , Biomarcadores/sangre , Quimiocinas/análisis , Quimiocinas/sangre , Citocinas/análisis , Citocinas/sangre , Diagnóstico Diferencial , Humanos , Inmunoensayo/instrumentación , Inmunoensayo/métodos , Inmunoensayo/normas , Péptidos/análisis , Péptidos/sangre , Valor Predictivo de las Pruebas , Proteómica/instrumentación , Proteómica/métodos , Proteómica/normas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Espondilitis Anquilosante/diagnóstico , Espondilitis Anquilosante/inmunologíaRESUMEN
Occurrence and distribution of chlorinated and non-chlorinated organophosphates in 72 groundwater samples from Germany under different recharge/infiltration conditions were investigated. Tris(2-chloro-1-methylethyl) phosphate (TCPP) and tris(2-chloroethyl) phosphate (TCEP) were the most frequently detected organophosphates in groundwater samples. Highest individual organophosphate concentrations (>0.1 µg L(-1)) were determined in groundwater polluted by infiltrating leachate and groundwater recharged via riverbank filtration of organophosphate-loaded recipients. In samples from springs and deep groundwater monitoring wells that are not affected by surface waters, organophosphate concentrations were mostly below the limit of detection. The occurrence (3-9 ng L(-1)) of TCPP and TCEP in samples from aquifers with groundwater ages between 20 and 45 years indicates the persistence of both compounds within the aquifer. At urban sites organophosphate-loaded precipitation, surface runoff, and leakage of wastewater influenced groundwater quality. For rural sites, where groundwater recharge is only influenced by precipitation, organophosphates were very rarely detectable in groundwater.
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Monitoreo del Ambiente , Retardadores de Llama/análisis , Organofosfatos/análisis , Plastificantes/análisis , Contaminantes Químicos del Agua/análisis , Agua Dulce/análisis , Alemania , Compuestos Organofosforados/análisis , Agua/análisis , Abastecimiento de AguaRESUMEN
UNLABELLED: Taurine transporter knockout mice show severe retinal degeneration at an early age. The study was designed to determine whether degeneration also takes place in the absence of light. Mice were maintained up to 6 weeks of age in cyclic lighting or in total darkness. Degeneration took place in both groups, but was more rapid in animals exposed to standard cyclic illumination. At the ultrastructural level the retinas showed features characteristic of apoptosis but not of necrosis. CONCLUSIONS: Cell differentiation is not seriously affected by the lack of a functional taurine transporter but mature photoreceptor cells do not survive without an intact transporter, even in the dark.
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Proteínas Portadoras/metabolismo , Luz , Glicoproteínas de Membrana/metabolismo , Proteínas de Transporte de Membrana , Células Fotorreceptoras/fisiopatología , Degeneración Retiniana/fisiopatología , Animales , Apoptosis/fisiología , Diferenciación Celular/fisiología , Inmunohistoquímica/métodos , Ratones , Ratones Noqueados , Microscopía Electrónica , Fagocitosis/fisiología , Células Fotorreceptoras/patología , Retina/patología , Retina/fisiopatología , Degeneración Retiniana/patologíaRESUMEN
We report on two patients with postinterventional retrogastric abscesses, one as a postoperative complication after partial pancreatectomy, one as a complication of biliary pancreatitis. In both cases, the abscess cavity could be completely drained by EUS-guided endoscopic application of a short "Amsterdam" stent, length 4 cm, 11.5 Fr. The stents could be removed by endoscopy after an interval of several weeks. In suitable cases EUS-guided endoscopic transgastral stenting appears to be the therapy of choice for retrogastral abscesses.
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Absceso Abdominal/terapia , Drenaje/instrumentación , Duodenoscopía/métodos , Pancreatectomía , Pancreatitis Aguda Necrotizante/cirugía , Esfinterotomía Endoscópica , Stents , Infección de la Herida Quirúrgica/terapia , Absceso Abdominal/diagnóstico por imagen , Anciano , Endosonografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infección de la Herida Quirúrgica/diagnóstico por imagen , Tomografía Computarizada por Rayos XRESUMEN
Organisms encoding multiple antibiotic resistance genes are becoming increasingly prevalent. In this report we describe a multiply resistant Klebsiella pneumoniae which possesses at least five different beta-lactamase genes. Isoelectric focusing, polymerase chain reaction and restriction fragment length polymorphism analysis identified TEM-1, multiple SHVs, OXA-9 and a plasmid-mediated ampC, beta-lactamase. Furthermore, Southern analysis and conjugation experiments established that most of the resistance genes were encoded on one large transferable plasmid. This report demonstrates the complexity of multiply resistant organisms.
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Proteínas Bacterianas , Klebsiella pneumoniae/genética , Plásmidos , beta-Lactamasas/genética , Adulto , Farmacorresistencia Microbiana/genética , Resistencia a Múltiples Medicamentos/genética , Humanos , Klebsiella pneumoniae/efectos de los fármacos , Masculino , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de RestricciónAsunto(s)
Células Intersticiales del Testículo/citología , 11-beta-Hidroxiesteroide Deshidrogenasas , 3-Hidroxiesteroide Deshidrogenasas/metabolismo , Animales , Biomarcadores , Diferenciación Celular , Hidroxiesteroide Deshidrogenasas/metabolismo , Células Intersticiales del Testículo/metabolismo , Masculino , Ratas , Receptores de HL/metabolismo , Testículo/citología , Testículo/embriologíaRESUMEN
Improvements in B lymphocyte function have been reported in hemodialysis patients receiving erythropoietin. The present investigation studied whether erythropoietin interferes with B cell function and the mechanisms of this effect. Antibody production by cultured peripheral blood mononuclear cells (PBMC) (7 days) from 15 dialysis patients before and during erythropoietin treatment and from 14 healthy controls was followed. IgG and IgA were formed less in the uremic group than in healthy subjects. After 8 weeks of erythropoietin (hematocrit rose from 19 to 31%) basal IgG formation by PBMC rose from 304 +/- 83 to 566 +/- 49 ng/ml (p less than 0.02), while IgA production rose from 380 +/- 121 to 563 +/- 362 ng/ml (p less than 0.01). IgM production, which appeared to be normal in uremia, remained unchanged during erythropoietin treatment. Production of IgG and IgA stimulated by pokeweed-mitogen was subnormal in uremia, but improved under erythropoietin therapy. To establish whether erythropoietin acted by itself or through correction of the renal anemia, healthy PBMC were directly incubated with 2 U/ml of erythropoietin. Under these conditions production of IgG (+19%), IgA (+28%), and IgM (+32%) was enhanced. Taken together these data indicate a direct stimulant effect of erythropoietin on B lymphocytes in end-stage renal failure.
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Anemia/tratamiento farmacológico , Linfocitos B/inmunología , Eritropoyetina/uso terapéutico , Inmunoglobulinas/biosíntesis , Diálisis Renal , Anemia/inmunología , Formación de Anticuerpos/efectos de los fármacos , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Activación de Linfocitos/inmunología , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/uso terapéutico , Uremia/complicaciones , Uremia/terapiaRESUMEN
Our intention was to conceive a simple model for the evaluation of well-defined leakages in the anesthetic breathing system. Utilization of any model requires a formula to calculate the corresponding leakage surfaces. METHOD. The leak is defined as the projection of a circle (radius r) onto the surface of a cylinder (radius R) in which anesthetic gas is flowing. If we remove the leakage surface from the cylinder and flatten it out this produces neither a circular nor an elliptic shape. We will develop an expression for the leakage surface depending on the two radii, r and R, in a two-dimensional coordinate system. RESULTS. Formulas (3), (4) and (5) can be used to compute leakage areas for our model. An analytic solution of the equations is impossible by the application of calculus, but a PC program for numeric integration can yield values with a sufficient degree of accuracy. Some results for well-defined leakages in breathing tubes (R = 11 mm) are shown. These show that the difference between the leakage area and the projected circle (radius r) can practically be neglected for some values of r. CONCLUSION. Leakages in most anesthetic breathing systems cause some gas loss. The main causes are leaking plug connections and screw joints. Damage to the breathing tubes or bellows is less significant. Part of the tidal volume will disperse into the environment via the leak. This might be hazardous for the patient because the breathing volume and inspiratory oxygen concentration are reduced and for the operating team because of air pollution. To examine how such parameters as flow, compliance and resistance cause loss of pressure and volume and variations in gas concentration in the case of leakages an appropriate model of practical use is needed. Application of the formulas derived from our model makes it possible to compare measurements gained from studying the impacts of leakages in cylindrical tubes of different diameters. By experimental research of pressure and volume loss we intend to gather reliable information that will allow us to make proper recommendations for efficient setting of the pressure disconnection alarm.