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Effects of Hypoxia and Exercise on In Vivo Lactate Kinetics and Expression of Monocarboxylate Transporters in Rainbow TroutOmlin, Teye D. 21 February 2014 (has links)
The current understanding of lactate metabolism in fish is based almost entirely on interpretation of concentration measurements that cannot be used to infer changes in flux. Moreover, the transporters regulating these fluxes have never been characterized in rainbow trout. My goals were: (1) to quantify lactate fluxes in rainbow trout under normoxic resting conditions, during acute hypoxia, and exercise by continuous infusion of [U-14C] lactate; (2) to determine lactate uptake capacity of trout tissues by infusing exogenous lactate in fish rest and during graded exercise, and (3) to clone monocarboxylate transporters (MCTs) and determine the effects of exhausting exercise on their expression. Such information could prove important to understand the mechanisms underlying the classic “lactate retention” seen in trout white muscle after intense exercise. In normoxic resting fish, the rates of appearance (Ra) and disappearance (Rd) of lactate were always matched (~18 to 13 µmol kg-1 min-1), thereby maintaining a low baseline blood lactate concentration (~0.8 mM). In hypoxic fish, Ra lactate increased from baseline to 36.5 µmol kg-1 min-1, and was accompanied by an unexpected 52% increase in Rd reaching 30.3 µmol kg-1 min-1, accounting for a rise in blood lactate to 8.9 mM. In exercising fish, lactate flux was stimulated > 2.4 body lengths per second (BL s-1). As the fish reached critical swimming speed (Ucrit), Ra lactate was more stimulated (+67% to 40.4 μmol kg-1 min-1) than Rd (+41% to 34.7 μmol kg-1 min-1), causing an increase in blood lactate to 5.1mM. Fish infused with exogenous lactate stimulated Rd lactate by 300% (14 to 56 μmol kg-1 min-1) during graded exercise, whereas the Rd in resting fish increased by only 90% (21 to 40 µmol kg-1 min-1). Four MCT isoforms were partially cloned and characterized in rainbow trout: MCT1b was the most abundant in heart, and red muscle, but poorly expressed in gill and brain where MCT1a and MCT2 were prevalent. MCT4 was more expressed in the heart. Transcript levels of MCT2 (+260%; brain), MCT1a (+90%; heart) and MCT1b (+50%; heart) were stimulated by exhausting exercise. This study shows that: (i) the increase in Rd lactate plays a strategic role in reducing the lactate load imposed on the circulation. Without this response, blood lactate accumulation would double; (ii) a high capacity for lactate disposal in rainbow trout tissues is elicited by the increased blood-to-tissue lactate gradient when extra lactate is administered; and (iii) rainbow trout may be unable to release large lactate loads rapidly from white muscle after exhausting exercise (lactate retention) because they poorly express MCT4 in white muscle and fail to upregulate its expression during exercise.
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New approaches to composite metal joiningJoesbury, Adam Michael January 2015 (has links)
This thesis explores new methods for achieving load-carrying joints between the dissimilar materials of continuous fibre reinforced polymer matrix composites and structural metals. The new composite-to-metal joining methods investigated in this work exploit the metal-to-metal joining techniques of arc micro-welding, resistance spot welding, and metal filler brazing, to form novel micro-architectured metal adherends that can be used for enhanced composite-to-metal joining. Through a combination of equipment instrumentation and metallographic inspection of fabricated prototype joints, understanding is gained of how materials respond when processed by manufacturing techniques that have not previously been exploited for dissimilar material joining. Mechanical testing of prototype joints; both to ultimate loading strength and partial failure states, with subsequent inspection of specimens and comparative performances evaluation enabled joining performance characterisation of the new joining methods. Key results include: the identification of micropin reinforced adhesive joints to exhibit pseudo-ductile failure characteristics, resistance spot weld reinforcement of adhesive joints to boost bonding performance, and the use of a polymer infused metal foam to overcome difficulties of thermoplastic to metal adhesion. Through this work knowledge of how novel micro-architectures reacted under mechanical loading enabled insights to be gained into how perceived manufacturing defects can benefit joining performance. Such examples include, localised material weakness that lead to global pseudo-ductile failure behaviour, and low-strength secondary joining mechanisms boosting primary load transfer systems. By comparison of the diverse joining methods investigated in this work, trends were identified that suggest joining performance between the two dissimilar materials is improved by increasing the direct interaction between the composite reinforcement fibres and the metal structure. It is demonstrated that joining improvements are gained by forming mechanical connections between metals and composite precursory material before the final manufacturing process of the composite.
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Effects of Hypoxia and Exercise on In Vivo Lactate Kinetics and Expression of Monocarboxylate Transporters in Rainbow TroutOmlin, Teye D. January 2014 (has links)
The current understanding of lactate metabolism in fish is based almost entirely on interpretation of concentration measurements that cannot be used to infer changes in flux. Moreover, the transporters regulating these fluxes have never been characterized in rainbow trout. My goals were: (1) to quantify lactate fluxes in rainbow trout under normoxic resting conditions, during acute hypoxia, and exercise by continuous infusion of [U-14C] lactate; (2) to determine lactate uptake capacity of trout tissues by infusing exogenous lactate in fish rest and during graded exercise, and (3) to clone monocarboxylate transporters (MCTs) and determine the effects of exhausting exercise on their expression. Such information could prove important to understand the mechanisms underlying the classic “lactate retention” seen in trout white muscle after intense exercise. In normoxic resting fish, the rates of appearance (Ra) and disappearance (Rd) of lactate were always matched (~18 to 13 µmol kg-1 min-1), thereby maintaining a low baseline blood lactate concentration (~0.8 mM). In hypoxic fish, Ra lactate increased from baseline to 36.5 µmol kg-1 min-1, and was accompanied by an unexpected 52% increase in Rd reaching 30.3 µmol kg-1 min-1, accounting for a rise in blood lactate to 8.9 mM. In exercising fish, lactate flux was stimulated > 2.4 body lengths per second (BL s-1). As the fish reached critical swimming speed (Ucrit), Ra lactate was more stimulated (+67% to 40.4 μmol kg-1 min-1) than Rd (+41% to 34.7 μmol kg-1 min-1), causing an increase in blood lactate to 5.1mM. Fish infused with exogenous lactate stimulated Rd lactate by 300% (14 to 56 μmol kg-1 min-1) during graded exercise, whereas the Rd in resting fish increased by only 90% (21 to 40 µmol kg-1 min-1). Four MCT isoforms were partially cloned and characterized in rainbow trout: MCT1b was the most abundant in heart, and red muscle, but poorly expressed in gill and brain where MCT1a and MCT2 were prevalent. MCT4 was more expressed in the heart. Transcript levels of MCT2 (+260%; brain), MCT1a (+90%; heart) and MCT1b (+50%; heart) were stimulated by exhausting exercise. This study shows that: (i) the increase in Rd lactate plays a strategic role in reducing the lactate load imposed on the circulation. Without this response, blood lactate accumulation would double; (ii) a high capacity for lactate disposal in rainbow trout tissues is elicited by the increased blood-to-tissue lactate gradient when extra lactate is administered; and (iii) rainbow trout may be unable to release large lactate loads rapidly from white muscle after exhausting exercise (lactate retention) because they poorly express MCT4 in white muscle and fail to upregulate its expression during exercise.
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Měření tlaku v infuzním systému / Presure measurement in infusion systemFialová, Lenka January 2016 (has links)
The first part of this work is about history of infusion technology, specially about recent developments in electronic infusion devices. Then, there are described basic principles of infusion pumps and syringe pumps. The second part introduces safety features of infusion technology. An occlusion alarm is one of them. There is described a method of measurement that verifies the functionality of this alarm in two instruments of different producers with various settings. Data obtained by this method are statistically processed and the results discussed.
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Untersuchung von Matrixeffekten in der quantitativen Analyse mit Flüssigkeitschromatographie-Tandem-Massenspektrometrie - Bestimmung, Kompensation und MethodenentwicklungRossmann, Julia 02 May 2019 (has links)
Das übergeordnete Ziel dieser Promotion war die Untersuchung und Kompensation des Matrixeffekts für die Analytik von Arzneimitteln in komplexen Probenmatrices mit LC-ESI-MS/MS-Technik. Zunächst konnte eine einfache analytische Methode für eine breite analytische Anwendbarkeit entwickelt werden. Es zeigte sich jedoch, dass die Matrixeffektkompensation zu einem Mehraufwand bei der Probenvorbereitung führt. Deshalb wurde anschließend der Mechanismus des Matrixeffektes auf die LC-ESI-MS/MS-Technik genauer untersucht. Die gewonnenen Erkenntnisse wurden anschließend eingesetzt, um eine einfache alternative Quantifizierungsmethode mittels der PCI eines internen Standards zu entwickeln.
Im ersten Teilprojekt wurde eine LC-ESI-MS/MS-Methode für die Analytik von häufig verschriebenen Antibiotika in Abwasserproben der Stadt Dresden entwickelt. Da weder Vergleichsmatrix für Abwasser zur Verfügung stand, noch für alle Zielanalyte isotopenmarkierte Standards erhältlich sind, wurde der stark variierende Matrixeffekt der Abwasserproben mittels der Standardaddition kompensiert. Die Ergebnisse der Methodenentwicklung zeigen, dass eine genaue und flexible Methode entwickelt werden konnte, die Matrixkompensation jedoch zu einem erhöhten Zeit- und Materialaufwand führt. Es wurde deutlich, dass neben bisher genutzten Kompensationsmethoden für den Matrixeffekt, wie Standardaddition und interner isotopenmarkierter Standards, neue alternative Strategien getestet werden müssen.
In dem zweiten Teilprojekt wurde daher der Matrixeffektmechanismus von Urin-, Plasma- und verschiedenen Abwasserproben bei der Messung von verschiedenen Arzneimitteln mittels LC-ESI-MS/MS analysiert. Die Ergebnisse der Untersuchungen mittels „post-column infusion“ konnten bisherige Erkenntnisse zu Matrixeffektmechanismen bestätigen und das Verständnis vertiefen. Matrixeffekte sind von der jeweiligen Zusammensetzung der Probenmatrix abhängig, aber auch substanzspezifisch. Dabei kommt es zwischen Analyt und Begleitsubstanzen zu einer Konkurrenz um freie Ladungsträger oder zu einer veränderten Anordnung/Verteilung innerhalb der ESI-Spray-Tröpfchen. Gleichzeitig zeigten die Ergebnisse, dass es auch andere Mechanismen, wie z. B. Ladungstransfers zwischen Analyt und Begleitsubstanzen, geben muss.
Schließlich wurden die Ergebnisse des zweiten Teilprojekts in einer innovativen Methodenentwicklung zur Matrixkompensation und zur Quantifizierung von 16 Arzneimitteln in Urinproben verwendet. Der Matrixeffekt der Substanzen mit vergleichbarer Signalsuppression konnte über einen einzelnen nachsäuleninfundierten internen Standard kompensiert werden. Die Ergebnisse zeigen einen deutlichen Vorteil der entwickelten Methode gegenüber Matrix-Kalibrierung in Präzision und Richtigkeit oder dem Einsatz von isotopenmarkierten internen Standards in Aufwand der Methodenentwicklung und Verbrauch von Standardsubstanzen.
Die Ergebnisse der vorliegenden Arbeit zeigen die Bedeutung, Komplexität und den Einfluss der Matrixeffekte in der Anwendung der LC-ESI-MS/MS-Technik. Einerseits sind geeignete Methoden für die Minimierung von Matrixeffekten wie Probenvorbereitung und Chromatographie nötig, andererseits müssen Ionisierungsmechanismen, insbesondere die Wechselwirkungen von Zielanalyten und Begleitsubstanzen, zukünftig Gegenstand weiterer Untersuchungen sein. Die Ergebnisse dieser Arbeit liefern wichtige Beiträge zur Verbesserung der Analytik von komplexen Proben mittels der LC-ESI-MS/MS-Technik. / The overall goal of this Ph.D. thesis was to investigate and compensate the matrix effect of the analysis of drugs in complex sample matrices with LC-ESI-MS/MS technique. First, a simple analytical method for a broad analytical applicability was developed for wastewater analysis. However, the matrix effect compensation embraced the main part effort in sample preparation. Therefore, the mechanism of the matrix effect on the LC-ESI-MS/MS technique was examined in more detail. The findings were used to develop an alternative quantification method using post-column infusion of an internal standard substance.
In the first project, a LC-ESI-MS/MS method was developed to analyze commonly prescribed antibiotics in wastewater samples of Dresden. Since neither comparison matrix for wastewater nor all isotopically-labeled analogs for the target analytes were available, the strongly varying matrix effect of the wastewater samples was compensated by standard addition. The results show that the developed method is precise and flexible, but the matrix effect compensation leads to an increased expenditure of time and materials. Besides previously used matrix effect compensation methods, such as standard addition and internal isotopically-labeled standard, new alternative strategies need to be tested.
Therefore, the matrix effect mechanism of various drugs and sample matrix combinations was examined in the second project using post-column infusion. The results confirmed previous findings on matrix effect mechanisms and deepened our understanding that matrix effects not only depend on the composition of the sample matrix but are also substance-specific. This results to a competition of free charge carriers between analyte and accompanying substances or to an alternated distribution within the ESI spray droplets. Furthermore, the results indicate that there are other mechanisms, such as charge transfer between analyte and concomitant substances.
The results of the second project were used to invent a method for matrix effect compensation and quantification of 16 drugs in urine samples. The matrix effects of the substances with comparable signal suppression were compensated by a single post-column infused internal standard. The developed method has a significant advantage over the matrix calibration regarding precision and accuracy as well as the use of isotopically-labeled internal standards in effort of method development and consumption of standard substances.
Finally, the results of this work show the importance, complexity and influence of the matrix effects in the application of the LC-ESI-MS/MS-technique. Suitable methods for minimizing matrix effects such as sample preparation and chromatography are needed and ionization mechanisms, in particular the interactions of target analytes with accompanying substances, should be investigated in future studies. The work of this Ph.D. project contributes to the improvement of the analysis of complex samples using the LC-ESI-MS/MS-technique.
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Från vision till integration : infusion av telemedicin : en översättningsprocess / From vision to integration : Infusion of telemedicine : a process of translationLinderoth, Henrik January 2000 (has links)
During the 1990's high expectations were put on telemedicine technology in health care organizations, which can be seen as a reflexion of the society's interest in IT. The use of tele-medicine is expected to improve the quality and decrease costs of health care services. However, if these expectations are to be attained the visions have to be translated into fields of application in local settings where the technology would be used. This could be seen as an infusion process, which means that the technology would incrementally be used in a comprehensive and integrated manner. In this thesis, four Swedish telemedicine projects are analyzed. The approach used is that of Actor network theory (ANT), which has enabled the development of a theory of the infusion process, implementation of IT-projects, and parts of ANT, e.g. the model of the translation process and the notion of inscription. By using the concept of translation, it is possible to see the infusion process as a process where the generic features of the technology (transmitting sound and pictures in real time) are translated into concrete activities in local settings. These fields of application are realized by the mobilization of different task-based networks, where the roles of the actors are defined by the task to be solved. An iterated mobilization of the network implies further that the network will become stabilized, which is a central dimension in the process of infusion. Another way to understand the process of infusion is to describe it as cycles of implementation, where one cycle symbolizes the implementation of a field of application, which is a result of the translation of the generic features of the technology. The inscriptions in the studied technology allow a high degree of flexibility of use and flexibility of action. The flexibility means that fields of application ought to be developed in interaction between actors in local settings, and supporting programs of action are to be identified, or developed, in order to integrate technology use into daily routines. The considerable numbers of failed of IT-project implementations can be explained by the fact that a traditional planning perspective has been used on technologies, which allow a high degree of flexibility of use and flexibility of action. However, by categorizing inscriptions in technological artifacts, it becomes possible to predict what kinds of implementation strategies are appropriate for different kinds of technologies. By viewing the implementation of open networking technologies as a process of translation, the infusion process will be facilitated and a comprehensive and integrated use of technology will be enabled. / digitalisering@umu
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Modelagem PK/PD na terapia antimicrobiana com carbapenêmico em pacientes sépticos críticos grandes queimados. \"Estudo da efetividade do meropenem administrado através de infusão intermitente versus estendida\" / PK/PD modelling in antimicrobial therapy with carbapenem in critically burn septic patients.\"Study of the effectiveness of meropenem administered by intermittent versus extended infusion\"Kupa, Leonard de Vinci Kanda 25 June 2019 (has links)
O meropenem é um carbapenêmico de amplo espectro e alta potência, largamente prescrito para tratamento de infecções graves causadas por bactérias sensíveis gram-negativas em pacientes críticos internados em Unidades de Terapia Intensiva. O objetivo do presente estudo foi avaliar a efetividade do antimicrobiano em pacientes grandes queimados, recebendo a dose recomendada 1 g q8h através da infusão intermitente de 0,5 hora que ocorreu até 2014 (grupo 1) comparada a infusão estendida de 3 horas que ocorreu após esse período (grupo 2). Investigaram-se 25 pacientes sépticos de ambos os sexos (6F/19M), 26 (21-34) anos, medianas (interquartil), 70 (60-75) kg, superfície corporal total queimada (SCTQ) 35 (16-42)%, SAPS 3: 55 (45-59) e Clcr 129 (95-152) ml/min que foram distribuídos em dois grupos. Registrou-se trauma térmico pelo fogo em 19/25 e trauma elétrico no restante dos pacientes (6/25), lesão inalatória (17/25), intubação orotraqueal e a necessidade de vasopressores em 18/25 pacientes. Duas amostras de sangue foram coletadas (3ª e 5ª horas) para dosagem sérica do meropenem por cromatografia líquida no período precoce do choque séptico. A farmacocinética foi investigada pela aplicação do modelo aberto de um compartimento e a abordagem PK/PD foi realizada com base no novo índice recomendado 100%fΔT>CIM. Evidenciou-se aumento do PCR 224 (179-286) versus 300 (264-339) mg/L, p=0,0411 e neutrofilia: 12 (8-17) versus 8 (2-15) células/mm3, p=0,1404, respectivamente nos grupos de infusão estendida versus infusão intermitente. Os níveis séricos obtidos mostraram diferença significativa entre grupos (p<0,0001) tanto para o pico 21 (21-22) mg/L versus 44 (42-45) mg/L, como para o vale 7,8 (7,3-9,5) mg/L versus 3,0 (2,6-3,7) mg/L. A farmacocinética mostrou-se alterada nos dois grupos frente aos dados de referência reportados em voluntários sadios. Significativa alteração ocorreu em diferentes proporções pela comparação entre os grupos relativamente à constante de eliminação 0,190 (0,157-0,211) versus 0,349 (0,334-0,382) h-1; meia-vida biológica 3,6 (3,3-4,4) versus 2,0 (1,8-2,1) h; depuração total corporal 8,6 (8,2-8,9) versus 5,3 (5,2-5,4) L/h; volume de distribuição 41,8 (39,9-44,5) versus 15,4 (14,1-16,2) L (p<0,0001). A infecção de ferida foi a mais prevalente nos dois grupos com 47% versus 38% dos isolados, sendo a Klebsiella pneumoniae, a principal enterobactéria. A abordagem PK/PD para patógenos CIM 1 a 4 mg/L mostrou cobertura até CIM 4 mg/L para a infusão estendida e até CIM 2 mg/L para infusão intermitente. Em conclusão, demonstrou-se a superioridade da infusão estendida decorrente de alterações na farmacocinética do meropenem em pacientes grandes queimados. O aumento do volume de distribuição contribuiu para o prolongamento da meia-vida e dos altos níveis de vale registrados, o justifica o impacto na cobertura antimicrobiana após infusão estendida e controle das infecções com cura desses pacientes. / Meropenem is a broad-spectrum agent widely prescribed for the treatment of septic shock caused by gram-negative susceptible strains in critically ill patients from the Intensive Care Units. Subject of the present study was to evaluate the drug effectiveness in critically ill septic burn patients in SIRS at the early period of septic shock receiving the recommended dose of Meropenem 1 g q8h by intermittent 0.5 hour infusion or the extended 3 hour infusion. Twenty-five septic patients were: (6F/19M), 26 (21-34) years, medians (quartiles), 70 (60-75) kg, total burn body surface (SCTQ) 35 (16-42) %, SAPS 3: 55 (45-59) and Clcr 129 (95-152) ml/min. Thermal trauma was registered in 19/25 and electrical trauma in the remaining patients (6/25), inhalation injury (17/25), orotracheal intubation and vasopressor requirement in 18/25 patients. Patients were distributed in two groups on the basis of the duration of drug infusion that occurred for the patients of group 1 (1g q8h 0.5 hr) until 2014, December in the hospital. In addition, the extended 3 hours infusion occurred after that period for patients enrolled afterwards (group 2). Pharmacokinetics was investigated after blood sampling at the third (3rd) hour and the fifth (5th) hour of starting the meropenem infusion. Serum drug measurement was done by liquid chromatography. A one compartment open model was applied and kinetic parameters were estimated. PK/PD approach based on the new recommended index of drug effectiveness 100% fΔT>MIC was performed, on the basis on PK parameters and the minimum inhibitory concentration, PD parameter. It was demonstrated a significant difference between groups (p <0.0001) related to the trough levels 7.8 (7.3-9.5) mg/L versus 3.0 (2.6-3.7) mg/L, respectively after extended infusion or intermittent infusion. Concerning the pharmacokinetics, it was shown profound changes on meropenem kinetic parameters in both groups of burn patients by comparison with the reference data reported in healthy volunteers. In addition, it is important to highlight that significant changes occurred also by comparison of PK data between groups of patients related to the parameters: elimination constant 0.190 (0.157-0.211) versus 0.349 (0.334-0.382) h-1; biological half-life 3.6 (3.3-4.4) versus 2.0 (1.8-2.1) hr; total body clearance 8.6 (8.2-8.9) versus 5.3 (5.2-5.4) L/hr; volume of distribution 41.8 (39.9-44.5) versus 15.4 (14.1-16.2) L. Concerning the inflammatory biomarker an increase of C-reactive protein was registered in both groups of septic patients in SIRS: 224 versus 300 mg/L, p = 0.0411, after the extended infusion versus intermittent infusion, respectively. Wound and bone were the most prevalent sites of infection in those patients of both groups. It was shown in the isolates the prevalence of Gram-negative strains 54/83 (65%) that were distributed in Enterobacteriaceae, K. pneumoniae 7/30 (23%), and Non-Enterobacteriaceae, P. aeruginosa 13/54 (24%) followed by Acinetobacter baumannii 11/54 (20%). Drug effectiveness against susceptible strains was demonstrated by PK/PD approach up to 4 mg/L over 2 mg/L, after the extended infusion or after intermittent infusion, respectively. In conclusion, the superiority of the extended infusion in septic burn patients at the earlier period of septic shock was demonstrated, once considerable increases on volume of distribution impacted the drug effectiveness of these patients. Cure was obtained by meropenem monotherapy in 22/25 patients; only three patients (3/25) received meropenem - colistine combined therapy due to Acinetobacter baumannii isolated.
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Uso perioperatório de solução cristaloide balanceada comparado ao de cloreto de sódio 0,9% em crianças submetidas à ressecção de tumor cerebral: ensaio clínico randomizado / Perioperative use of a balanced crystalloid solution versus saline in children undergoing brain tumor resection: a randomized clinical trialNeville, Mariana Fontes Lima 07 December 2018 (has links)
Objetivo: O objetivo deste estudo foi avaliar se o uso de uma solução cristaloide balanceada induz menos alterações metabólicas do que o cloreto de sódio 0,9% em crianças submetidas à ressecção de tumor cerebral. Desenho: Estudo fase II, unicêntrico, de superioridade, randomizado e controlado, realizado no Instituto de Oncologia Pediátrica da Universidade Federal de São Paulo, Brasil. População: crianças com idade entre 6 meses e 12 anos submetidas à ressecção de tumor cerebral. Intervenção: O uso de uma solução cristaloide balanceada durante e após (por 24 horas) ressecção de tumor cerebral foi comparado ao uso de cloreto de sódio 0,9%. Eletrólitos séricos e gasometria arterial foram coletados em três momentos: antes da cirurgia (basal); após a cirurgia [pós-operatório imediato (POI)]; e no primeiro dia pós-operatório (1º DPO). Desfecho primário: O desfecho primário deste estudo foi a variação do cloro sérico (pós-préop Cl), definida como a diferença absoluta entre as concentrações plasmáticas medidas no POI e antes da cirurgia. Desfechos secundários: Como desfechos secundários, foram avaliadas as variações (pós-préop) dos outros eletrólitos e do excesso de bases (BE); a incidência de acidose hiperclorêmica; e o escore de relaxamento cerebral (ERC), avaliado pelo neurocirurgião por meio de escala de 4 pontos. Resultados: 53 pacientes foram incluídos no estudo e randomizados; 27 receberam solução balanceada (grupo SB) e 26, cloreto de sódio 0,9% (grupo NaCl 0,9%). O pós-préop Cl mediano foi significativamente menor no grupo SB [0 (-1,0; 3,0)] do que no grupo NaCl 0,9% [6 (3,5; 8,5)], p < 0,01. O pós-préop BE mediano foi menor [-0,4 (-2,7; 1,3) versus -4,4 (-5,0; -2,3), p < 0,01] e acidose hiperclorêmica menos frequente (4% versus 67%, p < 0,01) no grupo SB do que no grupo NaCl 0,9%. O ERC foi comparável entre os grupos. Conclusão: Em crianças submetidas à ressecção de tumor cerebral, o uso de solução cristaloide balanceada reduziu a variação do cloro sérico comparado ao uso de cloreto de sódio 0,9%. Esses achados respaldam o uso de soluções balanceadas em crianças submetidas à ressecção de tumor cerebral. Registro no Clinical Trials: NCT NCT02707549 / Objective: The aim of this study was to determine if the use of a balanced crystalloid induces less metabolic derangements than 0.9% saline solution in children undergoing brain tumor resection. Design: Phase II, single center, superiority, randomized and controlled trial performed at Instituto de Oncologia Pediátrica, Universidade Federal de São Paulo, São Paulo, Brazil. Population: Pediatric patients (age range, 6 months to 12 years) undergoing brain tumor resection. Intervention: Use of a balanced crystalloid solution during and after (for 24 h) brain tumor resection was compared to saline 0.9%. Serum electrolyte and arterial blood gas analyses were performed before surgery (baseline), after surgery, and at postoperative day 1. Primary outcome: The primary trial outcome was the preoperative to postoperative variation in serum chloride (post-preop Cl) measured as the absolute difference between \"after surgery\" and baseline plasma concentrations. Secondary outcomes: As secondary outcomes, we measured the post-preop of other electrolytes and base excess (BE); hyperchloremic acidosis incidence; and the brain relaxation score, a four-point scale evaluated by the surgeon for assessing brain edema. Results: Fifty-three patients were included in the study; twenty-seven were randomized to receive a balanced crystalloid (balanced group) and twenty-six were randomized to receive 0.9% saline solution (saline group). The median post-preop Cl (mmol l-1) was significantly lower in the balanced [0 (-1.0; 3.0)] than in the saline group [6 (3.5;8.5); p < .01]. Median post-preop BE (mmol l-1) was lower [-0.4 (-2.7; -1.3) versus -4.4 (- 5.0; -2.3); p < .01] and hyperchloremic acidosis less frequent (4% versus 67%; p < .01) in the balanced group than in the saline group. Brain relaxation score was comparable between groups. Conclusions: In children undergoing brain tumor resection, balanced crystalloid solution infusion reduced variation in serum chloride. These findings support the use of balanced crystalloid solutions in children undergoing brain tumor resection
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Estudo das propriedades mecânicas de compósitos poliméricos reforçados por fibra de carbono e manufaturados pelos processos de laminação manual, infusão de resina e pré-impregnado / Mechanical properties study of the carbon fiber reinforced polymers manufactured via hand lay-up, resin infusion under flexible tooling and pre-pregKwai, Nan Te 30 September 2016 (has links)
Há um aumento da demanda mundial por materiais de alto desempenho, e os compósitos encaixam-se perfeitamente nesse nicho por serem resistentes e leves. Os compósitos poliméricos são feitos a partir da mistura de resina e reforço, no entanto, existem diversas metodologias para fazê-la. O presente trabalho compara em amplo aspecto, três desses métodos: laminação manual, infusão de resina e pré-impregnado. O primeiro é o método mais simples, o segundo é utilizado principalmente pela indústria náutica, e o terceiro pela indústria aeroespacial. Foram realizados diversos ensaios mecânicos como tração, flexão, cisalhamento, impacto, entre outros, e os resultados foram comparados entre si para demonstrar qualitativamente e quantitativamente as diferenças entre eles. Este trabalho demonstrou que o processo de pré-impregnado produz peças com propriedades cerca de 30% melhores que a infusão de resina, que por sua vez, possui um acréscimo de 25% sobre as propriedades da laminação manual. / There is an increasing worldwide demand for high performance materials, and therefore the composites reach a prominent position for being resistant and light weighted. Polymeric composites are made from mixing a given resin and the fibre; however, there are several different methodologies to do so. This work intends to compare, in a wide array, three of those methods: hand lay-up, resin infusion under flexible tooling and pre-pregs. The first is the simplest of all, the second is mainly used by the marine industry, and the third by the aerospace industry. Several mechanical tests such as tension, flexural, shear, impact, among others, were performed and their results were compared to infer their qualitatively and quantitatively differences. This study shows evidence that pre-preg properties are about 30% better than resin infusion, and the last has 25% better properties than hand lay-up.
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Impacto no sistema imunológico da utilização prolongada de morfina para tratamento da dor / Impact on the immune system of long-term morphine used through oral or spinal route in the treatment of neuropathic non-cancer painRosa, Christiane Pellegrino 17 March 2016 (has links)
Introdução. Apesar das evidências dos efeitos imunomodulatórios da morfina, não há na literatura estudos que tenham comparado a interação entre citocinas, imunidade celular (linfócitos T, B e NK) e a administração prolongada de morfina administrada pelas vias oral ou intratecal em doentes com dor crônica neuropática não relacionada ao câncer. Foram avaliados de forma transversal e comparativa 50 doentes com diagnóstico de dor lombar crônica e com presença de radiculopatia (dor neuropática) previamente operados para tratar hérnia discal lombar (Síndrome Dolorosa Pós- Laminectomia), sendo 18 doentes tratados prolongadamente com infusão de morfina pela via intratecal com uso de sistema implantável no compartimento subaracnóideo (grupo intratecal); 17 doentes tratados prolongadamente com morfina pela via oral (n=17) e 15 doentes tratados com fármacos mas sem opióides (grupo sem opioide). Foram analisadas as concentração das citocinas IL-2, IL-4, IL-8, TNFalfa, IFNy, IL-5, GM-CSF, IL-6, IL-10 e IL-1beta no plasma e no líquido cefalorraquidiano; imunofenotipagem de linfócitos T, B e células NK e avaliados os Índice de Escalonamento de Opióide (em percentagem de opióide utilizada e em mg), dose cumulativa de morfina (mg), duração do tratamento em meses, dose final de morfina utilizada (em mg), e equivalente de morfina por via oral (em mg). Resultados. Não houve diferença estatisticamente significativa entre o número de linfócitos T, B e NK nos doentes com morfina administrada pelas vias IT, VO e os não usuários de morfina. Houve correlação positiva entre as concentrações de linfócitos T CD4 e o Índice de Escalonamento de Opióide (em % e mg) nos doentes tratados com morfina por via intratecal. Houve correlação negativa entre as concentrações de células NK (CD56+) e o Índice de Escalonamento de Opióide (em % e mg) nos doentes tratados com morfina por via intratecal. Houve correlação positiva entre o número de células NK (CD56+) e a dose cumulativa de morfina (em mg) administrada pelas vias intratecal e oral. Houve correlação positiva entre as concentrações de linfócitos T CD8 e a duração do tratamento em meses nos doentes tratados com morfina pela via oral. As concentrações de IL-8 e IL-1beta foram maiores no LCR do que no plasma em todos os doentes da amostra analisada. As concentrações de IFNy no LCR foram maiores nos doentes que utilizavam morfina pela via oral e nos não usuários de morfina do que nos que a utilizavam pela via intratecal. As concentrações de plasmáticas de IL-5 foram maiores nos doentes utilizavam morfina pela via oral ou intratecal do que nos que não a utilizavam. A concentração de IL-5 no LCR correlacionou-se negativamente com a magnitude da dor de acordo com a EVA nos doentes tratados com morfina pelas via oral ou intratecal. Nos doentes tratados com morfina pelas via oral ou intratecal, a concentração de IL-2 no LCR correlacionou-se positivamente com a magnitude da dor de acordo com a EVA e negativamente com o Índice de Escalonamento de Opióide (em % e mg) e a dose cumulativa de morfina (em mg). As concentrações plasmáticas de GMCSF foram maiores nos doentes utilizavam morfina pela via oral ou intratecal do que nos não a utilizavam. A concentração de TNFalfa no LCR nos doentes tratados com morfina pela via intratecal correlacionou-se negativamente com o Índice de Escalonamento de Opióide (em % e mg), a dose cumulativa de morfina (em mg) e dose equivalente por via oral (em mg) de morfina. A concentração plasmática das citocinas IL-6 e IL-10 correlacionou-se negativamente com a duração do tratamento (em meses) nos doentes tratados com morfina administrada pela via oral. O Índice de Escalonamento de Opióide (em mg e %) correlacionou-se negativamente com as concentrações no LCR de IL-2 e TNFalfa nos doentes tratados com morfina administrada pela via intratecal. O Índice de Escalonamento de Opióide (em mg e %) correlacionou-se negativamente com as concentrações no LCR de IL-2 e IL-5 nos doentes tratados com morfina administrada pela via oral. Houve correlação negativa entre a intensidade da dor de acordo com a EVA e as concentrações de IL-5 e IL-2 no LCR nos doentes tratados com morfina administrada pelas vias oral e intratecal. Houve correlação negativa entre a intensidade da dor de acordo com a EVA e as concentrações plasmáticas de IL-4 nos doentes tratados com morfina administrada pela via intratecal. Houve correlação negativa entre a intensidade da dor de acordo com a EVA e as concentrações plasmáticas de IL-1beta nos doentes tratados com morfina administrada pela via intratecal. Conclusões: Os resultados sugerem associações entre citocinas e imunidade celular (células T , B e NK) e o tratamento prolongado com morfina administrada pela via oral ou intratecal. Estes resultados podem contribuir para a compreensão da imunomodulação da morfina administrada por diferentes vias em doentes com dor neuropática crônica não oncológica . São necessários mais estudos sobre os efeitos da morfina sobre o sistema imunológico / Objective: To analyze plasma and cerebrospinal fluid (CSF) cytokine levels and cell-mediated immunity (T, B and NK cells) of chronic neuropathic pain patients under long-term morphine treatment administered through the oral or spinal routes. Design: Cross- sectional clinical and laboratory analysis. Subjects:Fifty ambulatory patients with diagnosis of chronic low back pain and presence of radiculopathy (neuropathic pain) previously operated to treat lumbar disc hernia (failed back surgery syndrome) receiving long term morphine treatment (minimum 180 days); 18 patients receiving long term morphine into the intrathecal space through a implanted pump (\"spinal group\"); 17 patients treated with long-term oral morphine (\"oral group\") and 15 patients treated with non-opioid analgesics (\"without opioid group\"). Methods: Were analyzed plasma and cerebrospinal fluid concentrations of 10 cytokines using a multiplex system (Luminex®) for the following cytokines: IL- 2, IL-4, IL-8, TNFalfa, IFNy, IL-5, GM-CSF, IL-6, IL-10 and IL-1beta; immunophenotyping of lymphocytes T, B and NK cells. Results: There were no significant group demographic differences. No significant T, B and NK cells differences were observed between the 3 groups. CD4 levels and Opioid Escalation Index (OEI) were positively correlated in spninal group. NK cells levels and OEI were negatively correlated in spinal group. NK cells levels and cumulative morphine dose were positively correlated in spninal and oral groups. CSF concentrations of IL-8 and IL-1beta were higher than plasma concentrations in all groups. CSF concentration of FNg were higher in oral and without opioid group. Plasma IL-5 concentrations were higher in the oral and spinal groups compared to without opioid group. CSF concentration of IL-5 was negatively correlated with pain intensity in the oral and spinal groups. CSF concentrations of IL-2 was positively correlated with pain intensity and negatively correlated with OEI and cumulative morphine dose in the oral and spinal groups. GM-CSF plasma concentrations were higher in oral and spinal group compared to without opioid group. TNFa CSF concentrations was negatively correlated with OEI, cumulative morphine dose and equivalent oral morphine dose in the spinal group. IL-6 and IL-10 plasma concentrations were negatively correlated with treatment duration in the oral group. OEI The significant inverse correlations observed between pain intensity and the plasma IL-6 and IL-10 concentrations in patients receiving longterm i.t. opioids for chronic pain management, suggests that these cytokines are worthy of further investigation as possible biomarkers of persistent pain. CSF concentrations of IL-2 and TNFa were negatively correlated with OEI in spinal group. CSF concentrations of IL-2 and IL-5 were negatively correlated with OEI in oral group and with pain intensity in the oral and spinal group. Plasma concentrations of IL-4 was negatively correlated with pain intensity in spinal group. Plasma concentrations of IL-1beta were negatively correlated with pain intensity in spinal group. Conclusions: The results suggest associations between long term morphine treatment administered by oral or spinal routes and cytokines concentrations and cellmediated immunity (T, B and NK cells). These results can contribute to the understanding of immunomodulation by morphine administered through diferent routes in patients with chronic neuropathic non-cancer pain. Further studies on the effects of morphine on the immune system are needed
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