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In this study, a novel real-time polymerase chain reaction (PCR) assay (DermaGenius®2.0, PathoNostics BV, Maastricht, The Netherlands) and a recently developed microarray test (EUROArray Dermatomycosis, Euroimmun, Lübeck, Germany) were evaluated regarding their diagnostic specificity to identify dermatophyte DNA. The tests were compared to conventional methods and sequencing. The microarray Dermatomycosis test allows the detection of 50 dermatophytes and definitive identification of 23 dermatophyte species, 6 yeasts and moulds combined in one test. In comparison, real-time PCR is able to identify 11 dermatophytes and one yeast at the species level. Using the EUROArray, 22 out of 24 dermatophyte species were correctly identified. Using real-time PCR, 9 out of the 11 different dermatophytes included in the test kit were correctly identified. Both molecular tests for detection and differentiation of dermatophytes are useful tools for daily clinical practice. The real-time PCR test does not detect as many species, and specificity is slightly lower. However, real-time PCR is a very fast and easy to perform test, especially since no post-PCR step is necessary. Real-time PCR detects the most frequent dermatophytes like T. rubrum, T. interdigitale, and M. canis without any problems. The EUROArray is more elaborate to perform in the lab, due to the hybridization step. However, the EUROArray shows higher specificity and can detect a much broader range of causative agents, including rare species, in dermatomycology.
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ADN de Hongos/clasificación , ADN de Hongos/genética , Dermatomicosis , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Trichophyton/clasificación , Trichophyton/genética , ADN de Hongos/aislamiento & purificación , Alemania , Humanos , Microsporum/clasificación , Microsporum/genética , Microsporum/aislamiento & purificación , Países Bajos , Trichophyton/aislamiento & purificaciónRESUMEN
We report dissipative magnon-photon coupling caused by the cavity Lenz effect, where the magnons in a magnet induce a rf current in the cavity, leading to a cavity backaction that impedes the magnetization dynamics. This effect is revealed in our experiment as level attraction with a coalescence of hybridized magnon-photon modes, which is distinctly different from level repulsion with mode anticrossing caused by coherent magnon-photon coupling. We develop a method to control the interpolation of coherent and dissipative magnon-photon coupling, and observe a matching condition where the two effects cancel. Our work sheds light on the so-far hidden side of magnon-photon coupling, opening a new avenue for controlling and utilizing light-matter interactions.
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We use electrical detection, in combination with microwave transmission, to investigate both resonant and nonresonant magnon-photon coupling at room temperature. Spin pumping in a dynamically coupled magnon-photon system is found to be distinctly different from previous experiments. Characteristic coupling features such as modes anticrossing, linewidth evolution, peculiar line shape, and resonance broadening are systematically measured and consistently analyzed by a theoretical model set on the foundation of classical electrodynamic coupling. Our experimental and theoretical approach paves the way for pursuing microwave coherent manipulation of pure spin current via the combination of spin pumping and magnon-photon coupling.
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OBJECTIVE: To assess hearing rehabilitation in patients with congenital aural atresia using an active middle-ear implant (Vibrant Soundbridge). METHODS: Of a cohort of 70 microtia and atresia patients, 10 underwent Vibrant Soundbridge implantation between 2008 and 2021. Two of the 10 patients had binaural implantation, resulting in 12 ears for analysis. Pre- and post-operative audiometry data were analysed, and patient satisfaction was evaluated. Surgical issues regarding coupling sites and outcomes were analysed. RESULTS: Pure tone average (0.5, 1, 2 and 4 kHz) improved from a pre-operative mean (standard deviation) of 65.3 (8.7) dB HL to a post-operative mean of 26.8 (4.9) dB HL. This resulted in a mean pure tone average gain of 38.5 dB HL. The results indicate no obvious difference between stapes (n = 8) and incus (n = 4) coupling. The mean effective gain for 0.5, 1, 2 and 4 kHz was -17.8 dB HL (standard deviation = 4.3). Concerning effective gain, Vibrant Soundbridge performed best at 2 kHz. Patients reported high overall satisfaction, good sound quality and strongly improved directional hearing. CONCLUSION: An active middle-ear implant (Vibrant Soundbridge) allows hearing rehabilitation in selected atretic ears, and provides long-term hearing stability in children and adults.
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Oído , Prótesis Osicular , Adulto , Niño , Humanos , Resultado del Tratamiento , Oído/cirugía , Oído/anomalías , AudiciónRESUMEN
Traumatic and non traumatic spinal cord injury are rare and an orphan disease in comparison to common diseases. Those affected represent a very special patient population in the treatment even at the site of the accident and in emergency medicine and require a high level of professional expertise. The rehabilitation with the complexity of a spinal cord injury can only succeed with a multiprofessional team that is less focused on the often similar diagnoses according to the International Classification of Diseases (ICD) but on functional disorders and associated activity impairments. Only then the best possible integration and participation/inclusion in sociocultural and professional life can be achieved. In addition to the importance of classical physiotherapy and occupational therapy, this article highlights important but often missing team players, such as neurourology and electrical stimulation. In addition, the problems of frequent and some less recognized complications, such as autonomic dysfunction and the benefits of airway management are highlighted. For a comprehensive overview of rehabilitation in spinal cord injury, reference textbooks and guidelines are recommended that are cited in the text.
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Enfermedades del Sistema Nervioso Autónomo , Medicina de Emergencia , Terapia Ocupacional , Traumatismos de la Médula Espinal , Humanos , Traumatismos de la Médula Espinal/diagnóstico , Actividades Cotidianas , Enfermedades del Sistema Nervioso Autónomo/complicacionesRESUMEN
BACKGROUND: For the investigation of the biomechanical properties of bone, various testing devices have been described. However, only a limited number have been developed to test the vertebral body of small animals. The aim of this study was to develop and validate a new bone testing device, which investigates the different biomechanical properties in small-animal vertebrae as a whole, three-dimensional unit, respecting its anatomical structure. METHODS: Thirty-five twelve-week-old female Sprague Dawley rats were utilized. Group 1 was composed of 17 rats with a normal bone metabolism without osteoporosis, while Group 2 consisted of 18 rats with manifest osteoporosis, 8 weeks after ovariectomy. The 5th lumbar vertebra of each animal was tested using the new bone testing device. This device has the ability to be adjusted to the slanted nature of each individual vertebral body and fix the vertebra in a natural position to allow for a non-dislocating axial force application. The device is designed to respect the anatomical three-dimensional shape of the vertebral body, thus avoiding the application of non-anatomic, non-physiological forces and thus preventing a distortion of the biomechanical testing results. The parameters investigated were stiffness, yield load, maximum load and failure load, and the results were compared to current literature values. RESULTS: The conduction of the biomechanical bone testing of the vertebral bodies with the new device was conductible without any instances of dislocation of the vertebrae or machine malfunctions. Significant differences were found for stiffness, maximum load and failure load between groups, with a lower value in the osteoporotic rats in each parameter tested. The yield load was also lower in the osteoporotic group, however not significantly. The values achieved correlate with those in current literature. CONCLUSIONS: This study demonstrates that the newly developed testing machine is easy to handle and produces valid data sets for testing biomechanical bone parameters of whole vertebral bodies in an established small animal model. Therefore, it can be utilized, also as reference data, to test different structural properties and changes in vertebral bone, for example, in different metabolic settings or under the influence of different pharmaceutical entities in further studies.
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Osteoporosis , Fracturas de la Columna Vertebral , Ratas , Femenino , Animales , Vértebras Lumbares/fisiología , Ratas Sprague-Dawley , Fenómenos Biomecánicos , Cuerpo VertebralRESUMEN
AIMS/HYPOTHESIS: The fetal insulin hypothesis suggests that variation in the fetal genotype influencing insulin secretion or action may predispose to low birthweight and type 2 diabetes. We examined associations between 25 confirmed type 2 diabetes risk variants and birthweight in individuals from the Danish Inter99 population and in meta-analyses including Inter99 data and reported studies. METHODS: Midwife records from the Danish State Archives provided information on mother's age and parity, as well as birthweight, length at birth and prematurity of the newborn in 4,744 individuals of the population-based Inter99 study. We genotyped 25 risk alleles showing genome-wide associations with type 2 diabetes. RESULTS: Birthweight was inversely associated with the type 2 diabetes risk alleles of ADCY5 rs11708067 (beta = -33 g [95% CI -55, -10], p = 0.004) and CDKAL1 rs7756992 (beta = -22 g [95% CI -43, -1], p = 0.04). The association for the latter locus was confirmed in a meta-analysis (n = 24,885) (beta = -20 g [95% CI -29, -11], p = 5 x 10(-6)). The HHEX-IDE rs1111875 variant showed no significant association among Danes (p = 0.09); however, in a meta-analysis (n = 25,164) this type 2 diabetes risk allele was associated with lower birthweight (beta = -16 g [95% CI -24, -8], p = 8 x 10(-5)). On average, individuals with high genetic risk (>or=25 type 2 diabetes risk alleles) weighed marginally less at birth than those with low genetic risk (<25 type 2 diabetes risk alleles) (beta = -35 g [95% CI -69, -2], p = 0.037). CONCLUSIONS/INTERPRETATION: We report a novel association between the fetal ADCY5 type 2 diabetes risk allele and decreased birthweight, and confirm in meta-analyses associations between decreased birthweight and the type 2 diabetes risk alleles of HHEX-IDE and CDKAL1. No strong general effect on birthweight can be ascribed to the 25 common type 2 diabetes risk alleles.
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Adenilil Ciclasas/genética , Peso al Nacer/genética , Quinasa 5 Dependiente de la Ciclina/genética , Diabetes Mellitus Tipo 2/genética , Estudio de Asociación del Genoma Completo/métodos , Proteínas de Homeodominio/genética , Factores de Transcripción/genética , Alelos , Femenino , Genotipo , Humanos , Recién Nacido , Embarazo , ARNt MetiltransferasasRESUMEN
Recycling schemes are being used worldwide to reduce the impact of municipal waste. Those using public funds are usually obliged to set performance indicators by which the standards of such schemes can be measured. In the UK, a set of statutory Best Value Performance Indicators (BVPI) must be reported annually, such as the Quality of Fair Access, which monitors the public's access to recycling facilities within 1000 m (known as BVPI 91). This work shows that BVPI 91, and performance indicators like it, quantify only very basic recycling services. A much more sensitive performance indicator is developed in this paper, labelled as the Maximum Practicable Recycling Rate Provision (MPRRP) achievable by a local authority. It indicates the percentage of local waste that could be reasonably recycled using the services provided, calculated on the basis of the average composition of the local waste, the local population coverage for collection of any materials, and nationally provided information stating how much of each material stream is generally suitable (practical) for recycling. Evidence for the usefulness of this new quantity is presented. Although this paper refers a particular performance indicator in the UK, its findings are applicable to all urban areas worldwide needing to monitor recycling service. Furthermore, the MPRRP could be used for planning purposes, and for determining the level of performance of an existing service, by comparing its predicted recycling rate to that actually obtained. Further work is now being carried out on this.
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Conservación de los Recursos Naturales , Sistemas de Información Geográfica , Evaluación de Programas y Proyectos de Salud , Eliminación de Residuos , Reino Unido , ResiduosRESUMEN
Decellularized scaffolds represent a promising alternative for mitral valve (MV) replacement. This work developed and characterized a protocol for the decellularization of whole MVs. Porcine MVs were decellularized with 0.5% (w/v) SDS and 0.5% (w/v) SD and sterilized with 0.1% (v/v) PAA. Decellularized samples were seeded with human foreskin fibroblasts and human adipose-derived stem cells to investigate cellular repopulation and infiltration, and with human colony-forming endothelial cells to investigate collagen IV formation. Histology revealed an acellular scaffold with a generally conserved histoarchitecture, but collagen IV loss. Following decellularization, no significant changes were observed in the hydroxyproline content, but there was a significant reduction in the glycosaminoglycan content. SEM/TEM analysis confirmed cellular removal and loss of some extracellular matrix components. Collagen and elastin were generally preserved. The endothelial cells produced newly formed collagen IV on the non-cytotoxic scaffold. The protocol produced acellular scaffolds with generally preserved histoarchitecture, biochemistry, and biomechanics.
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Bioprótesis , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Prótesis Valvulares Cardíacas , Válvula Mitral , Ingeniería de Tejidos/métodos , Andamios del Tejido , Animales , Fenómenos Biomecánicos , Proliferación Celular , Células Cultivadas , Técnicas de Cocultivo , Colágeno Tipo IV/metabolismo , Replicación del ADN , Elastina/metabolismo , Fibroblastos/metabolismo , Glicosaminoglicanos/metabolismo , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Hidroxiprolina/metabolismo , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Válvula Mitral/inmunología , Válvula Mitral/metabolismo , Válvula Mitral/trasplante , Válvula Mitral/ultraestructura , Células Madre/metabolismo , Sus scrofa , Factores de TiempoRESUMEN
BACKGROUND: Little is known about single nucleotide polymorphism (SNP) in different lots of varicella vaccines distributed by the manufacturers. Recently, the genetic analysis of several genomic regions revealed a polymorphism in different vaccine lots of Varilrix manufactured by GlaxoSmithKline. These findings need attention since mutations in the vaccine strain could result in changes of virulence and efficacy of the vaccine. OBJECTIVES: To identify SNPs in three varicella vaccine lots of Varilrix and to compare the results with that of Varivax as well as the published sequences of the Oka vaccine strain (V-Oka) and its parental virus (P-Oka). STUDY DESIGN: The open reading frames (ORF) 1, 6, 10, 21, 50, 54, and 62 were analyzed by sequencing of amplified DNA fragments. RESULTS: Wild-type nucleotides identical to that of P-Oka and/or the European wild-type reference strain Dumas and in contrast to V-Oka could be identified in ORF 1 of a Varilrix vaccine lot distributed in 1991. In the ORF 62 probably responsible for attenuation of V-Oka, this vaccine strain contained 16 SNPs which were nearly all wild-type-like. By contrast, different lots of the Varivax vaccine revealed uniform sequencing results. The vaccine Varilrix 1999 showed a high similarity to the Varivax vaccine currently available. CONCLUSIONS: The obvious genetic diversity of different lots of the varicella vaccine Varilrix cannot be explained with the coexistence of several strain variants in the vaccine, but most likely with different seed lot preparations used for vaccine production.
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Vacuna contra la Varicela , Herpesvirus Humano 3/clasificación , Polimorfismo de Nucleótido Simple , Sustitución de Aminoácidos , Genotipo , Herpesvirus Humano 3/genética , Humanos , Sistemas de Lectura AbiertaRESUMEN
Local authorities throughout the UK are refining or implementing curbside recycling schemes as they attempt to achieve challenging statutory recycling targets. Despite the importance of curbside schemes there are few published studies that have reported on actual measured levels and frequency of participation by residents, hindering transferability of lessons learned nationally and internationally. This paper reports measurements and analysis over at least four weeks for three different curbside recycling schemes operating in England, with at least 1400 samples in each. It is found that the participation rate is higher in schemes that collect more types of materials. Participation rates of 38%, 49% and 65% were measured for schemes that collected 1, 2 and 3 material types, respectively. The increase appears to be related not only to extra participants setting out the additional materials, but also increased participation for the common materials. It is found that for one scheme, more households tend to set out plastics and cans compared to newspapers.
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Participación de la Comunidad/estadística & datos numéricos , Conservación de los Recursos Naturales/estadística & datos numéricos , Eliminación de Residuos/estadística & datos numéricos , Adolescente , Adulto , Anciano , Aluminio , Recolección de Datos , Inglaterra , Humanos , Persona de Mediana Edad , Periódicos como Asunto , Papel , Publicaciones Periódicas como Asunto , PlásticosRESUMEN
Small angle X-ray data from purified forms of inner or cytoplasmic and outer membranes from Escherichia coli have been obtained and appear to be qualitatively similar. Transitory changes are apparent in the circularly averaged X-ray profiles from inner membranes. Such results could be due to the loss or denaturation of peripheral membrane proteins. Some partially dried forms of outer membrane are partly ordered and produce diffraction patterns which support an underlying bilayer structure. An extra light membrane fraction which results from membrane preparations utilizing a French pressure cell for spheroplast disruption has been characterized and shown to be similar to inner membrane. The purified membranes produce small angle X-ray diffraction patterns which are much different from those of lipid dispersions and the differences are attributable to the high protein content of the intact membranes. While the small angle X-ray region may be useful for characterizing the membrane preparations, the paucity of detail in the diffraction pattern suggest that it will be of little value in describing the complex underlying membrane structure.
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Membrana Celular/ultraestructura , Escherichia coli/ultraestructura , Lípidos de la Membrana/análisis , Esferoplastos/ultraestructura , Difracción de Rayos X/instrumentaciónRESUMEN
The potential of electrospray ionization (ESI) Fourier transform ion cyclotron mass spectrometry (FTICR-MS) to assist in the structural characterization of monomeric and dimeric derivatives of the macrophage colony stimulating factor beta (rhM-CSF beta) was assessed. Mass spectrometric analysis of the 49 kDa protein required the use of sustained off-resonance irradiation (SORI) in-trap cleanup to reduce adduction. High resolution mass spectra were acquired for a fully reduced and a fully S-cyanylated monomeric derivative (approximately 25 kDa). Mass accuracy for monomeric derivatives was better than 5 ppm, after applying a new calibration method (i.e., DeCAL) which eliminates space charge effects upon high accuracy mass measurements. This high mass accuracy allowed the direct determination of the exact number of incorporated cyanyl groups. Collisionally induced dissociation using SORI yielded b- and y-fragment ions within the N- and C-terminal regions for the monomeric derivatives, but obtaining information on other regions required proteolytic digestion, or potentially the use of alternative dissociation methods.
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Factor Estimulante de Colonias de Granulocitos y Macrófagos/análisis , Secuencia de Aminoácidos , Cromatografía Líquida de Alta Presión , Ciclotrones , Escherichia coli/metabolismo , Análisis de Fourier , Humanos , Espectrometría de Masas , Datos de Secuencia Molecular , Oxidación-Reducción , Fragmentos de Péptidos/análisis , Pliegue de Proteína , Proteínas RecombinantesRESUMEN
Remarkable improvement in hemostasis after cardiopulmonary bypass has been achieved by treatment with the proteinase inhibitor aprotinin, but the mechanism is still unclear. The present study is designed to elucidate the importance of platelet adhesive (glycoprotein Ib) or aggregatory (glycoprotein IIbIIIa) receptors on this hemostatic function in cardiopulmonary bypass and its improvement by aprotinin treatment. To determine whether the first pass of blood through the circuit or a continuous proteolytic attack is the main cause of platelet damage, we gave two different dose regimens of aprotinin treatment to patients undergoing coronary artery bypass grafting. Part I of the study consisted of a double-blind trial on 60 patients. Patients received placebo or aprotinin infusion (total 6.10(6) KIU) before and during bypass. A consecutive group of 22 matching patients received one single bolus of aprotinin in the pump prime (2.10(6) KIU). Blood samples were collected before and during operation to assess the effect of bypass and aprotinin on platelets and the activation of the various proteases in relation to hemostasis expressed in blood loss and blood requirements. The adhesive platelet membrane Ib glycoproteins were decreased by 50% in the untreated patients within 5 minutes of cardiopulmonary bypass and remained low during bypass, whereas glycoprotein Ib did not decrease in either group of aprotinin-treated patients. The platelet membrane IIbIIIa glycoproteins did not significantly change during bypass in either group, but fibrinogen binding to these receptors improved significantly in the 6.10(6) KIU aprotinin-treated group at the end of bypass as compared with initial values. The high continuous dose of 6.10(6) KIU aprotinin inhibited the clotting and kallikrein/kinin system throughout the operation; the pump prime dose of 2.10(6) KIU inhibited these systems only initially. Although the fibrinolytic activity was effectively inhibited in both aprotinin groups, fibrinolytic activity became apparent only at the end phase of bypass in the placebo group. However, improved hemostasis was observed intraoperatively from the start of bypass and resulted in a 40% lower blood loss intraoperatively and postoperatively and consequently a 40% lower total blood requirement in the aprotinin-treated patients than in the untreated patients. Our results therefore demonstrate that the improved hemostasis during and after bypass in patients treated with aprotinin has specifically to be attributed to a preserved adhesive capacity of platelets that was affected in the first pass of blood through the cardiopulmonary bypass circuit.
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Aprotinina/farmacología , Puente Cardiopulmonar , Hemostasis/efectos de los fármacos , Adhesividad Plaquetaria/efectos de los fármacos , Agregación Plaquetaria/efectos de los fármacos , Coagulación Sanguínea/efectos de los fármacos , Puente Cardiopulmonar/efectos adversos , Método Doble Ciego , Fibrinógeno/metabolismo , Hemorragia/epidemiología , Humanos , Incidencia , Calicreínas/antagonistas & inhibidores , Glicoproteínas de Membrana Plaquetaria/efectos de los fármacosRESUMEN
In this prospective study, the effect of the antiproteinase aprotinin on anticoagulation during cardiopulmonary bypass was compared with placebo treatment in a randomized double-blind fashion. The kallikrein-inhibiting capacity was significantly increased in aprotinin-treated patients and decreased in the control patients. The intrinsic clotting system was also inhibited by aprotinin. We demonstrated during cardiopulmonary bypass and in vitro a significantly prolonged activated clotting time and a remarkable prolongation of the activated partial thromboplastin time by aprotinin at low heparin concentrations, whereas the antithrombin III consumption was significantly reduced. Aprotinin synergistically enhanced the anticoagulation by heparin, which allowed reduced heparinization. This is of clinical importance for use in both heparin-resistant and heparin-sensitive patients undergoing cardiopulmonary bypass and may also have advantages for routine use during bypass to reduce the adverse effects of heparin-protamine complexes.
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Aprotinina/uso terapéutico , Coagulación Sanguínea/efectos de los fármacos , Puente Cardiopulmonar/métodos , Antitrombina III/efectos de los fármacos , Puente de Arteria Coronaria , Método Doble Ciego , Fibrinopéptido A/metabolismo , Heparina/administración & dosificación , Humanos , Calicreínas/antagonistas & inhibidores , Tiempo de Tromboplastina Parcial , Recuento de Plaquetas/efectos de los fármacos , Estudios Prospectivos , Tromboxanos/sangre , Tiempo de Coagulación de la Sangre TotalRESUMEN
The requirements that have to be met by an on-line autotransfusion system (ATS) in case of massive blood loss are a sufficient capacity for reinfusing the shed blood, an optimal hemocompatibility, ability to prevent reinfusion of aspirated air, and ease of operation. In a previous study we tested a diaphragm pump in our pneumatically driven ATS that met these requirements. In this study a centrifugal pump was used as an outflow pump in otherwise the same system. A centrifugal pump has important advantages: It prevents the occurrence of massive air embolism, accidental obstruction of the outflow line will not cause bursting of the tubing, and there is no spallation. There are also indications that a centrifugal pump causes less stimulation of the coagulation cascade than do other pumps. Because of these advantages, we were interested in the hemocompatibility and pumping characteristics of the centrifugal pump in our ATS. From this study we conclude that the hemocompatibility of the centrifugal pump was not significantly different from that of the previously tested diaphragm pump. Also, the system can easily and safely be operated by non-specialized personnel. Because of the advantages, especially in pumping characteristics, the centrifugal pump is our choice in on-line ATSs.
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Transfusión de Sangre Autóloga/instrumentación , Hemoglobinas/análisis , Animales , Perros , Agregación Plaquetaria , Recuento de PlaquetasRESUMEN
To determine whether aprotinin can provide a significant improvement of hemostasis in cardiopulmonary bypass using a membrane oxygenator, we tested this drug in a prospective, randomized, double-blind, placebo-controlled clinical trial. The subjects were 80 male patients undergoing cardiopulmonary bypass for coronary artery bypass grafting. Forty patients received aprotinin and 40 patients served as placebo controls. Aprotinin (4 x 10(6) KIU) was given as a continuous infusion, starting before operation and continuing until after cardiopulmonary bypass; additionally, 2 x 10(6) KIU aprotinin was added to the pump prime. Intraoperative and postoperative bleeding, respectively two thirds and one third of the total perioperative blood loss, were both significantly reduced in the aprotinin-treated group (p less than 0.01). The total average perioperative blood loss, corrected to a hemoglobin concentration of 7 mmol/L, was 550 mL in the aprotinin-treated patients versus 900 mL in the control patients. This reduction in blood loss, furthermore, significantly decreased the amount of postoperative blood transfusions (p less than 0.05) and increased the percentage of patients who did not receive postoperative donor blood from 42% to 68%. Aprotinin increased the activated clotting time significantly during cardiopulmonary bypass, which led to a reduction in heparin usage. The improved hemostasis during operation, despite the prolonged activated clotting time, might even abolish the need for heparin conversion with protamine at the end of cardiopulmonary bypass, thus allowing retransfusion through cardiotomy suction to be continued, which saves the blood that is currently lost with vacuum suction.
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Aprotinina/uso terapéutico , Pérdida de Sangre Quirúrgica/prevención & control , Puente Cardiopulmonar , Oxigenadores de Membrana , Aprotinina/farmacología , Transfusión Sanguínea , Hemostasis/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , beta-Tromboglobulina/análisisRESUMEN
Production of human parathyroid hormone (hPTH) by Escherichia coli TG1:I52cIts was studied. The hPTH is expressed as a fusion protein under control of the bacteriophage lambda pR promoter. The organism grows on glucose/mineral salt medium and the expression of the gene product was investigated under variation of temperature and growth rate prior to and after induction. hPTH formation largely depends on cultivation temperature and is optimal for a temperature shift from 30 to 38 degrees C. Product expression is growth coupled and specific hPTH concentration is independent of growth rate. The results are compared with a previous study on E. coli N4830:pEX-PPTH grown on complex media.
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Escherichia coli/metabolismo , Hormona Paratiroidea/biosíntesis , Proteínas Recombinantes/biosíntesis , Medios de Cultivo , Escherichia coli/crecimiento & desarrollo , TemperaturaRESUMEN
Human parathyroid hormone (hPTH) has been bacterially expressed in bioreactors as cro-beta-galactosidase-hPTH fusion protein. We have developed a large-scale purification scheme that exploits the pH-dependent differential solubility of hPTH and a two-step chromatographic procedure. We demonstrate that in a number of assay systems, the recombinant material obtained by this procedure is biologically active.
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Hormona Paratiroidea/genética , Animales , Huesos/metabolismo , Calcio/metabolismo , División Celular/efectos de los fármacos , Células Cultivadas , Embrión de Pollo , Cromatografía Líquida de Alta Presión , AMP Cíclico/biosíntesis , Fermentación , Humanos , Concentración de Iones de Hidrógeno , Hidrólisis , Técnicas de Cultivo de Órganos , Hormona Paratiroidea/metabolismo , Hormona Paratiroidea/farmacología , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Recombinantes de Fusión/farmacología , beta-Galactosidasa/genética , beta-Galactosidasa/metabolismoRESUMEN
A remarkable reduction of postoperative blood loss after cardiopulmonary bypass (CPB) has been achieved by prophylactic treatment with the proteinase inhibitor aprotinin. To reveal the mode of action of aprotinin, 23 CPB patients were randomised for aprotinin (2 x 10(6) KIU in the pump prime) or placebo treatment during CPB. Blood samples were collected before and during operation. Blood loss and blood requirements were 50% lower in the aprotinin treated patients than in the untreated patients. The adhesive capacity of platelets assessed by the amount of platelet membrane glycoprotein Ib (GP Ib) decreased by 50% in the untreated patients within 5 min of CPB and remained low during CPB, whereas GP Ib did not decrease in the aprotinin treated patients. Fibrinogen degradation products indicating plasmin activity could only be measured after 30 min of CPB in the untreated, but not in the aprotinin treated patients. The kallikrein inhibiting capacity was 34% decreased in the untreated patients within 5 min of CPB, while it increased by 84% and remained high during CPB in the aprotinin treated patients. Our results demonstrate that the improved haemostasis during and after CPB in patients treated with aprotinin can be attributed to the preserved adhesive capacity of platelets. It remains to be found whether aprotinin has a primary effect on platelets or a secondary effect by plasmin or kallikrein inhibition.