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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Influencia do diclofenaco sodico na absorção, concentração serica e excreção da amoxicilina : estudos em ratos / Influence of sodium diclofenac on absorption, serum concentration and excretion of amoxicillin in rats

Junqueira, Marcelo de Souza 02 February 2006 (has links)
Orientadores : Thales Rocha de Mattos Filho, Francisco Carlos Groppo / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-06T06:37:26Z (GMT). No. of bitstreams: 1 Junqueira_MarcelodeSouza_D.pdf: 648615 bytes, checksum: 3b46ad75b56af2255d981b942d82fa8f (MD5) Previous issue date: 2006 / Resumo: O uso de antimicrobianos e de antiinflamatórios é prática comum na odontologia, embora haja escassez de trabalhos sobre seu uso simultâneo. Portanto, o objetivo deste trabalho foi avaliar, em ratos, os efeitos do diclofenaco sódico na absorção, concentração sérica e excreção da amoxicilina utilizando a técnica de perfusão tecidual e o método microbiológico. Foram utilizados 108 ratos Wistar machos (12 grupos, n= 9), com peso entre 150 e 200 g. Foram administrados aos animais: amoxicilina 25 mg/Kg (grupos: G1, D1, S1 e R1), diclofenaco sódico 2,5 mg/Kg + amoxicilina 25 mg/Kg (grupos: G2, D2, S2 e R2) e 1,0 mL de solução de cloreto de sódio a 0,9% (grupos: G3, D3, S3 e R3). As drogas foram administradas por injeção intraluminal aos animais dos grupos G1, G2, G3, D1, D2 e D3 e por via oral aos animais dos grupos S1, S2, S3, R1, R2 e R3. Foram avaliadas nos tempos de 15, 30, 45, 60, 120, 180, 240, 300 e 360 minutos as concentrações plasmáticas e urinárias de amoxicilina e a absorção gastrintestinal ¿in vitro¿ do antimicrobiano. O diclofenaco sódico causou uma redução significativa na absorção intestinal e um aumento na excreção renal do antimicrobiano em ratos, com conseqüente diminuição da sua concentração sérica. Portanto, em algumas situações clínicas, a eficácia da amoxicilina poderia ser prejudicada pela sua co-administração com o diclofenaco sódico / Abstract: The prescription of antibiotics associated to anti-inflammatory drugs is common in dentistry; however its effects have not been studied enough. Thus, the aim of this work was to evaluate the influence of sodium diclofenac on absorption, serum concentration and excretion of amoxicillin, in rats, by the microbiologic and tissue perfusion methods. The sample consisted of 108 male Wistar rats (12 groups, 9 rats each), weighing 150¿200 g. The animals were given: amoxicillin 25 mg/Kg (groups G1, D1, S1 and R1), sodium diclofenac 2.5 mg/Kg plus amoxicillin 25 mg/Kg (groups G2, D2, S2 and R2) and 1.0 mL of solution of sodium chloride 0.9% (groups G3, D3, S3 and R3). The animals in the groups G1, G2, G3, D1, D2 and D3 were administered drugs by intra-luminal injection and the animals in the groups S1, S2, S3, R1, R2 and R3 were administered drugs p.o. After 15, 30, 45, 60, 120, 180, 240, 300 and 360 minutes, were evaluated the blood and urine concentrations of amoxicillin and the ¿in vitro¿ absorption of the antibiotic. Sodium diclofenac had decreased the intestinal absorption, increased renal excretion and, consequently, decreased the serum concentration of the amoxicillin. Thus, sodium diclofenac could decrease the efficacy of amoxicillin under some clinical situations / Doutorado / Farmacologia, Anestesiologia e Terapeutica / Doutor em Odontologia
42

Efeito do diclofenaco sodico sobre a concentração serica e tecidual da amoxicilina e sobre a infecção estafilococica : estudo in vivo, em ratos

Simões, Roberta Pessoa 12 August 2018 (has links)
Orientador: Francisco Carlos Groppo / Dissertação (mestrado) Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-12T01:52:09Z (GMT). No. of bitstreams: 1 Simoes_RobertaPessoa_M.pdf: 1951478 bytes, checksum: fa986a3125f61b41fa59a6ea91b73746 (MD5) Previous issue date: 2000 / Resumo: O presente trabalho teve por objetivo observar o efeito da amoxicilina, do diclofenaco sódico e da associação de ambos sobre a infecção estafilocócica induzida em tecidos granulomatosos, em ratos. Também foram avaliadas as concentrações sérica e teciduais da amoxicilina, observando o efeito da associação do diclofenaco sódico sobre as mesmas. Trinta animais receberam implantes de quatro esponjas de poliuretana subcutâneamente no dorso e, após 14 dias, dois dos tecidos resultantes (posicionados caudalmente) receberam 0,5mL de um inóculo de 108 ufcjmL de S. aureus ATCC 25923. Dois dias após, os animais foram divididos em grupos de seis, os quais receberam uma dose única de amoxicilina 50mgjkgjvo (grupo 1), amoxicilina 25 mg/kg/vo (grup02), diclofenaco sódico 2,5mg/kg/im (grupo 3), diclofenaco sódico 2,5mg/kg/im + amoxicilina 50mg/kg/vo (grupo 4) e soro fisiológico 1mLjanimal/vo (controle). Após 6h, dois tecidos granulomatosos (posicionados em direção à cabeça) e 10 _L de soro sangüíneo foram obtidos de cada animal, os quais foram dispostos em diferentes placas com MHA semeado com 108 ufcjmL de S. aureus ATCC 25923. Após incubação, foram medidos os halos de inibição proporcionados pelos tecidos granulomatosos e pelo soro sangüíneo. Dez microlitros, provenientes dos tecidos infectados após dispersão com auxílio de sonicador em tubos de ensaio contendo 10m L de NaCI foram distribuídos em placas contendo ágar salt manitol; permitiram a contagem do número de microrganismos em cada grupo. Os resultados mostraram concentrações teciduais de amoxicilina de 6,6 I-Ig/g para o grupo 1; 2,8I-1g/g para o grupo 2 e 0,8 I-Ig/g para o grupo 4. As concentrações séricas do antimicrobiano encontradas foram 11,6 I-Ig/mL para o grupo 1; 5,4I-1g/mL para o grupo 2 e 1,3I-1g/mL para o grupo 4. Não foram observadas diferenças estatisticamente significantes entre o número de microrganismos dos grupos 1, 2 e 4. Entretanto, estes foram significativamente diferentes do controle e do grupo 3, os quais foram diferentes entre si. Foi concluído que, embora o diclofenaco sódico (grupo 4) tenha diminuído a concentração tecidual da amoxicilina, a concentração resultante foi suficiente para permitir uma redução do número de microrganismos viáveis similar à observada nos grupos 1 e 2 / Abstract: The aim of this work was to observe the effect of the amoxicillin, sodium diclofenac and amoxicillin plus sodium diclofenac against staphylococcal infection in granulomatous tissues. Four polyurethane sponges placed under the back skin of thirty rats induced these tissues. After 14 days two tissues (tall position) received 0.5 mL of 108 ufc of S. aureus ATCC 25923/mL. Two days after, the animais were divided into five groups of six each. Group 1 received an only dose of amoxicillin 50mgjkgjpo, group 2 received amoxicillin 25mgjkgjpo, group 3 received sodium diclofenac 2.5mgjkgjim, group 4 received sodium diclofenac 2.5mg/kg/im plus amoxicillin 50mg/kg/po, and group 5 (control group) received NaCI 1mLjpo. After six hours of drug administration, two tissues of each animal were removed. Blood was collected from cervical plexus and centrifuged. Then, 10j.JL of serum were placed on paper disks. These disks and tissues were placed on dishes with Mueller Hinton agar inoculated with 108 ufc of Staphylococcus aureus/mL The dishes were incubated over 18 hours, and the inhibition zones were measured. The infected granulomatous tissues were placed in 10mL of NaCI, and dispersed by sonic system. Ten microliters of this suspension were spread on salt manitol agar dishes. The resulting microorganisms were counted after the incubation. Results showed tissue concentrations of amoxicillin of 6.6 ug/g for group 1; 2.8ug/g for group 2, and 0.8 ug/g for group 4. Serum concentration of amoxicillin showed 11.6 ug/mL for group 1; 5.4ug/mL for group 2, and 1.3ug/mL for group 4. Statistically significant differences among the number of microorganisms groups 1, 2, and 4 were not observed. However, these previous groups were statistically different from groups 3 and 5, which were statistically different from each other. It was concluded that, although sodium diclofenac (group 4) reduced amoxicillin concentration in the tissue, the resulting concentration was enough to reduce the count of microorganism. Also, the number of microorganisms of group 4 was similar to the one observed in groups 1 and 2 / Mestrado / Farmacologia, Anestesiologia e Terapeutica / Mestre em Odontologia
43

Development and investigation of antibiotic resistance in <i>E. coli</i> using aminoglycosides

Malott, Bradley January 2019 (has links)
No description available.
44

Evolutionary analysis of the β-lactamase families / Analyse évolutive des familles de β-lactamase

Keshri, Vivek 05 July 2018 (has links)
Les antibiotiques β-lactamines sont parmi les médicaments antimicrobiens les plus anciens et les plus utilisés. L'enzyme bactérienne β-lactamase hydrolyse l'antibiotique β-lactame en cassant la structure de base "anneau β-lactame". Pour identifier les nouvelles β-lactamases, une étude complète a été réalisée dans diverses bases de données biologiques telles que Human Microbiome Project, env_nr et NCBI nr. L'analyse a révélé que les séquences ancestrales putatives et les recherches de profil HMM jouaient un rôle important dans l'identification de la base de données homologue et métagénomique à distance dans l'enzyme β-lactamase existante comme matière noire. Les larges analyses phylogénétiques des β-lactamases existantes et nouvellement identifiées représentent les nouveaux clades dans les arbres. En outre, l'activité d'hydrolyse des antibiotiques β-lactamines de séquences nouvellement identifiées (provenant d'archées et d'humains) a été étudiée en laboratoire, ce qui montre l'activité de la β-lactamase. La deuxième phase de l'étude a été entreprise pour examiner l'évolution fonctionnelle des β-lactamases. Premièrement, des séquences de protéines ß-lactamase 1155 ont été extraites de la base de données ARG-ANNOT et des valeurs CMI la littérature correspondante. Les résultats ont révélé que l'activité fonctionnelle de la β-lactamase évoluait de manière convergente au sein de la classe moléculaire. La troisième phase de cette thèse représente le développement d'une base de données intégrative de β-lactamases. La base de données publique actuelle de β-lactamases a des informations limitées, par conséquence, une base de données intégrative a été développée. / The β-lactam antibiotics are one of the oldest and widely used antimicrobial drugs. The bacterial enzyme β-lactamase hydrolyzes the β-lactam antibiotic by breaking the core structure “β-lactam ring”. To identify the novel β-lactamases a comprehensive investigation was performed in different biological databases such as Human Microbiome Project, env_nr, and NCBI nr. The analysis revealed that putative ancestral sequences and HMM profile searches played a significant role in the identification of remote homologous and uncovered the existing β-lactamase enzyme in the metagenomic database as dark-matter. The comprehensive phylogenetic analyses of extant and newly identified β-lactamase represent the novel clades in the trees. Further, the β-lactam antibiotic hydrolysis activity of newly identified sequences (from archaea and human) was investigated in laboratory, which shows β-lactamase activity.The second phase of the investigation was undertaken to examine the functional evolution of β-lactamases. First, 1155 β-lactamase protein sequences were retrieved from ARG-ANNOT database and MIC values from the corresponding literature. The results revealed that the functional activity of β-lactamase evolved convergently within the molecular class.The third phase of this thesis presents development of an integrative β-lactamase database. The existing public database of β-lactamase has limited information, therefore, an integrative database was developed.
45

Μελέτες με σκοπό την ολική σύνθεση της Ecteinascidin 743 : νέες συνθετικές μεθοδολογίες στη φαρμακευτική χημεία

Ψαρρά, Βασιλική 19 April 2010 (has links)
Η Ecteinascidin 743 είναι ένα σπουδαίο αντικαρκινικό φάρμακο, που καταστρέφει μέσω αλκυλίωσης τα καρκινικά κυττάρα και είναι εμπορικά διαθέσιμο με το όνομα Yondelis. Χρησιμοποιείται στην Ευρώπη, τη Ρωσία και τη Νότια Κορέα για τη θεραπεία του σαρκώματος του μαλακού ιστού, δηλαδή καρκίνου των ιστών που υποστηρίζουν το σώμα, όπως οι μύες, τα αιμοφόρα αγγεία και άλλα είδη ιστών που υποστηρίζουν και προστατεύουν τα όργανα του σώματος. Η Ecteinascidin 743 βρίσκεται υπό κλινικές δοκιμές για τη θεραπεία και άλλων μορφών καρκίνου, όπως του καρκίνου του μαστού, του προστάτη, των ωοθηκών, των νεφρών, των πνευμόνων και του μελανώματος. Απομονώθηκε από το μικρό θαλάσσιο οργανισμό, Ecteinascidia turbinate, που ζει στις θάλασσες της Καραϊβικής και ανακαλύφθηκε ότι έχει αντικαρκινική δράση το 1969. Αυτό το φυσικό προϊόν αποτέλεσε πηγή έμπνευσης για την παρούσα ερευνητική εργασία, όπου στην ρετροσυνθετική του πορεία (Εικόνα 3) περιλαμβάνεται η σύνθεση ενός μορίου πιπεραζίνης, καθώς και ενός β-λακταμικού δακτυλίου. Οι β-λακτάμες χρησιμοποιούνται σήμερα ως βακτηριοκτόνα, αντιβιοτικά, αναστολείς των πρωτεασών σερίνης και αναστολείς της ακυλομεταφεράσης της χοληστερολης (acyl-CoA: cholesterol acyltransferase, ACAT), η οποία είναι υπεύθυνη κυρίως για την αθηροσκληρωτική στεφανιαία καρδιακή νόσο. Η ασθένεια αυτή αποτελεί ήδη την πιο κοινή μορφή ασθένειας που προσβάλλει την καρδιά και μία σημαντική αιτία πρόωρου θανάτου στην Ευρώπη, σε κράτη της Βαλτικής, τη Ρωσία, τη Βόρεια και Νότια Αμερική, την Αυστραλία και τη Νέα Ζηλανδία. Η αθηροσκλήρωση σχετίζεται με την στεφανιαία καρδιακή νόσο, η οποία αποδίδεται στην ανικανότητα της στεφανιαίας κυκλοφορίας να τροφοδοτεί με επαρκές αίμα το μυ της καρδιάς και τους περιβάλλοντες ιστούς. Οι παράγοντες που οδηγούν στην αθηροσκλήρωση είναι τα υψηλά επίπεδα χοληστερόλης, η υπέρταση, ο διαβήτης, το κάπνισμα, οι κακές διατροφικές συνήθειες, η παχυσαρκία και η έλλειψη σωματικής άσκησης. Οι παραπάνω δράσεις των β-λακταμών έχουν καταστήσει πολύ ενδιαφέρουσα τη στερεοεκλεκτική και εναντιοεκλεκτική σύνθεση αυτών. Ένας β-λακταμικός δακτύλιος είναι μία λακτάμη με δομή ετεροατομικού τετραμελούς δακτυλίου, που αποτελείται από τρία άτομα άνθρακα και ένα άτομο αζώτου. Ο β-λακταμικός δακτύλιος είναι μέρος της δομής μερικών κατηγοριών β- λακταμικών αντιβιοτικών, όπως οι πενικιλίνες, οι κεφαλοσπορίνες, οι κεφαμυκίνες, οι καρβαπενέμες, οι μονοβακτάμες, και οι τρινέμες. Οι ενώσεις των β-λακταμών παρασκευάστηκαν σύμφωνα με την Mannich αντίδραση μέσω σουλφινιμινών. Οι πιπεραζίνες χρησιμοποιούνται σήμερα ως μυκητοκτόνα, αγχολυτικά, αντιικά, και ανταγωνιστές του υποδοχέα της σεροτονίνης (5-HT). Η τελευταία θεραπευτική ικανότητα των πιπεραζινών είναι πλέον ένα θέμα εκτενούς επιστημονικής έρευνας και περιλαμβάνει υποδοχείς-στόχους που ανήκουν στην κατηγορία των υποδοχέων συζευγμένων με G-πρωτεΐνη (G-ptotein-coupled receptors, GPCRs). Η εκλεκτικότητα των πιπεραζινών για τις GPCRs εμφανίζεται εξαιτίας της βασικότητας. Αυξάνοντας το μέγεθος του όρθο υποκαταστάτη σε Ν-άρυλο πιπεραζίνες, αυξάνεται η ικανότητα πρόσδεσής τους και η λειτουργική τους δραστικότητα. Οι πιπεραζίνες είναι οργανικές ενώσεις, που αποτελούνται από έναν εξαμελή δακτύλιο, ο οποίος περιέχει δύο άτομα αζώτου, που βρίσκονται στις θέσεις 1 και 4 του δακτυλίου. Οι ενώσεις των πιπεραζινών παρασκευάστηκαν σύμφωνα με την Diels-Alder αντίδραση μέσω σουλφινιμινών. Οι σουλφινιμίνες αποτέλεσαν το μόριο-κλειδί για την σύνθεση όλων των τελικών επιθυμητών προϊόντων και είναι γνωστές ως πολύ καλοί πρόδρομοι αμινών, όταν αντιδράσουν με οργανομεταλλικές ενώσεις [RLi, RMgX (αντιδραστήρια οργανολιθίου, αντιδραστήρια Grignard)]. Οι οπτικώς καθαρές σουλφινιμίνες είναι σημαντικές δομικές μονάδες (building blocks) στην ασύμμετρη σύνθεση άμινο παραγώγων, και παρασκευάζονται σε πολύ καλές αποδόσεις μέσω ενός σταδίου από αρωματικές, ετεροαρωματικές και αλιφατικές αλδεΰδες. Στην παρούσα ερευνητική μελέτη συντέθηκαν νέες β-λακταμικές ενώσεις και υποκατεστημένες ενώσεις πιπεραζίνης, συμπληρώνοντας έτσι και ενισχύοντας τα ήδη υπάρχοντα δεδομένα για τις συγκεκριμένες κατηγορίες ενώσεων αφενός και, αφετέρου, παρέχοντας νέα δεδομένα για την ολική σύνθεση του φυσικού προϊόντος, Ecteinascidin 743 (σύνθεση των εξαμελών αζόξυ προϊόντων 18, 19 και 20). Η ρετροσυνθετική ανάλυση της Ecteinascidin 743, που περιγράφηκε αρχικά, δύναται να εφαρμοστεί, σύμφωνα με τα αποτελέσματα της παρούσας ερευνητικής εργασίας. / Ecteinascidin 743 is an important antitumor drug that can service a novel way of killing cancer cells, and it is sold under the brand name Yondelis. It has been approved for use in Europe, Russia and South Korea for the treatment of advanced soft tissue sarcoma, cancers of the supporting tissues of the body, such as muscles, fat, blood vessels or in any other tissues that support, surround and protect the organs of the body. Ecteinascidin 743 is undergoing clinical trials for the treatment of breast, prostate, ovarian, renal, lung, and melanoma cancers. It is isolated from the Caribbean tunicate Ecteinascidia turbinate, and was found to have anticancer activity in 1969. We were inpired by this natural product and as we can observe from its retrosynthetic analysis (Scheme 3), the synthesis of a piperazine molecule and a β-lactam ring are involved. The extreme importance of β-lactams serving not only as bactericidal and as key structural units of several important antibiotics, but also as mechanism-based inhibitors of serine proteases and as inhibitors of acyl-CoA cholesterol acyltransferase (ACAT), which is mainly responsible for atherosclerotic coronary heart disease. Coronary heart disease is already the most common form of disease affecting the heart and is an important cause of premature death in Europe, the Baltic states, Russia, North and South America, Australia and New Zealand. Atherosclerosis is most commonly equated with atherosclerotic coronary artery disease, which is rendered in the failure of the artery circulation to supply with sufficient blood the heart muscle and the surrounding tissues. Risk factors for the coronary heart disease include high levels of cholesterol, hypertension, diabetes, smoking, bad diet habbits, obesity, and lack of excercise. The above activities of β-lactams have propelled strong resurgent interest toward their stereoselective and enantioselective synthesis. A β-lactam ring is a lactam with a heteroatomic four-membered ring structure, consisting of three carbon atoms and one nitrogen atom. Penicillins, cephalosporins, cephamycins, carbapenems, monobactams, and trinems are classified as b-lactam antibiotics. β-Lactams were prepared by the Mannich reaction using sulfinimines. Piperazines are used now-a-days as antifungals,antidepressants, antiviral, and serotonin receptor antagonists (5-HT). The latter therapeutic area of piperazines has been the subject of intense research and includes targets belonging to the G-Protein- Coupled Receptor (GPCR) superfamily. The selectivity of piperazines towards GPCRs has deen attributed to their basicity. Increasing the size of the ortho substituent in N-aryl piperazines resulted in an increase in binding affinity and functional potency. Piperazines are organic compounds that consists of a six-membered ring containing two opposing nitrogen atoms, at the 1 and 4 positions of the ring. Piperazines were prepared by the Diels-Alder reaction using sulfinimines. Sulfinimines are the key-compounds for the synthesis of the final desirable products described herein and excellent precursors of amines, when they react with organometallic compounds [RLi, RMgX (organolithium reagents, Grignard reagents)]. Enantiomerically pure sulfinimines representing, important building blocks in the asymmetric synthesis of amine derivatives, are prepared in high yields in one step from aromatic, heteroaromatic, and aliphatic aldehydes. In this project, novel β-lactam compounds and substituted piperazine compounds were synthesized, in order to complete and highlight the already existing data for these specific compounds classes and provide new data about the total synthesis of the natural product, Ecteinascidin 743 (synthesis of six-membered azoxy products 18, 19 and 20). The retrosynthetic analysis of Ecteinascidin 743 could be viable given the result described in Scheme 44.
46

Metodologías bioanalíticas para el diagnóstico in vitro de alergia a antibióticos ß-lactámicos

Juárez Rodriguez, María José 12 July 2022 (has links)
[ES] Los fármacos pertenecientes a la familia de los ß-lactámicos son los antibióticos más usados en todo el mundo. Estudios recientes revelan que hasta un 10% de la población refiere haber presentado síntomas alérgico, esta porción de la población se considera "alérgica". En el diagnóstico de la alergia a antibióticos ß-lactámicos existen varios tipos de pruebas que sirven para orientar y confirmar la presencia de una alergia, clasificadas como ensayos in vivo e in vitro. En lo que se refiere a los ensayos in vivo, la detección de los procesos alérgicos más comunes se realiza mediante pruebas de exposición oral controladas, y pruebas intraepidérmicas e intradérmicas. No obstante, estas pruebas tienen sus limitaciones como es el riesgo de inducir reacciones alérgicas sistémicas graves. Por todo ello, su práctica requiere personal entrenado. Este requisito limitan la realización de este tipo de pruebas a centros hospitalarios especializados. La aplicación y desarrollo de técnicas de diagnóstico in vitro tiene como objetivo llegar a un diagnóstico de la alergia sin riesgos para el paciente. Entre las distintas pruebas serológicas y celulares que se pueden emplear, la detección de IgE específica es una de las más extendidas debido a que, dada su sensibilidad y especificidad, y mayor seguridad. Los sistemas de diagnóstico in vitro actuales utilizan una instrumentación analítica cara y de gran tamaño, así como materiales desechables caros, manejados por personal cualificado, por lo que este tipo de pruebas se realizan únicamente por servicios de alergia y/o análisis clínicos de grandes centros sanitarios. En consecuencia, hay una necesidad de desarrollar nuevos métodos de diagnóstico que cumplan los requisitos de sensibilidad, rapidez, sencillez, multiplexado y portabilidad, a un precio reducido para su implantación en todo tipo de laboratorios clínicos de los diferentes niveles de atención sanitaria. Por este motivo, en esta tesis doctoral se plantea como objetivo principal la puesta a punto de un inmunoensayo múltiple, utilizando la tecnología de disco compacto para la detección y cuantificación in vitro de niveles de IgE específica a un amplio espectro de antibióticos ß-lactámicos en muestras de suero humano. Las limitaciones más críticas para la determinación de IgE específica multianalito mediante métodos inmunoquímicos son las relacionados con la sensibilidad y selectividad. Por lo tanto, una parte importante de la tesis se ha centrado en la preparación y caracterización de un panel antígenos ß-lactámicos, selección de inmunoreactivos, formato y estudio de diferentes parámetros claves del inmunoensayo. Otra parte importante de la tesis se ha enfocado en abordar la mejora de la reproducibilidad de los resultados. La estrategia ha consistido en estudiar diferentes sistemas de calibración con el objetivo de estandarizar la cuantificación de los métodos in vitro de diagnóstico de este tipo de alergias. Para ello, se han evaluado las prestaciones de la calibración homóloga, heteróloga y el uso de un patrón interno, comparado sus prestaciones analíticas (relación señal ruido, sensibilidad, reproducibilidad, etc.) con el sistema de referencia. Finalmente, la validación del inmunoensayo se realizó con un conjunto de 101 muestras de suero de pacientes y controles. Los resultados obtenidos han sido comparados con los obtenidos mediante las técnicas de referencia, mostrando una mejor sensibilidad, especificidad, precisión, y linealidad. La capacidad múltiplex de la tecnología de disco compacto permitió llevar a cabo paralelamente estudios de reactividad cruzada frente a diferentes antibióticos ß-lactámicos esclareciendo el patrón de reconocimiento de los pacientes. En esta línea de trabajo, el uso de otras estrategias de conjugación de haptenos ha resultado en la mejora de la sensibilidad clínica del ensayo, identificando nuevos epítopos / [CA] Els fàrmacs que pertanyen a la família dels beta-lactams, són els antibiòtics d'us més estès a tot el món. Estudis recents posen de manifest que fins un 10% de la població ha presentat símptomes d'al·lèrgia, essent considerats població al·lèrgica als beta-lactams. En el diagnòstic de l'al·lèrgia front aquest tipus d'antibiòtics, existeixen diferents tipus de proves que serveixen per orientar i confirmar la presència d'una al·lèrgia, classificades com assajos in vivo i in vitro. Pel que fa als assajos in vivo, la detecció dels processos al·lèrgics més comuns es realitza mitjançant proves d'exposició oral controlades, i proves intra-epidèrmiques i intradèrmiques. No obstant això, aquestes proves tenen les seues limitacions com és el risc d'induir reaccions al·lèrgiques sistèmiques greus. Per tot això, la seua pràctica requereix personal entrenat. Aquests requisits limiten la realització d'aquesta mena de proves a centres hospitalaris especialitzats. L'aplicació i desenvolupament de tècniques de diagnòstic in vitro té com a objectiu arribar a un diagnòstic de l'al·lèrgia sense riscos per al pacient. Entre les diferents proves serològiques i cel·lulars que es poden emprar, la detecció d'IgE específica és una de les més esteses donada la seua sensibilitat, especificitat, i major seguretat. Els sistemes de diagnòstic in vitro actuals utilitzen una instrumentació analítica cara i de gran grandària, així com materials d'un sol ús també cars, que requereixen de personal qualificat, per la qual cosa aquest tipus de proves es realitzen únicament per serveis d'al·lèrgia i/o anàlisis clíniques de grans centres sanitaris. En conseqüència, hi ha una necessitat de desenvolupar nous mètodes de diagnòstic que complisquen els requisits de sensibilitat, rapidesa, senzillesa, multiplexatge i portabilitat, a un preu reduït per a la seua implantació en tota mena de laboratoris clínics dels diferents nivells d'atenció sanitària. Per aquest motiu, en aquesta tesi doctoral es planteja com a objectiu principal la posada a punt d'un immunoassaig múltiple, utilitzant la tecnologia de disc compacte per a la detecció i quantificació in vitro de nivells d'IgE específica a un ampli espectre d'antibiòtics ß-lactáms en mostres de sèrum humà. Les limitacions més crítiques per a la determinació d'IgE específica multianàlit mitjançant mètodes inmunoquímics estan directament relacionades amb la sensibilitat i selectivitat. Per tant, una part important de la tesi s'ha centrat en la preparació i caracterització d'un panell antígens ß-lactáms, selecció d'inmunoreactius, del format d'assaig i estudi de diferents paràmetres claus de l'immunoassaig. Una altra part important de la tesi s'ha enfocat a abordar la millora de la reproductibilitat dels resultats. L'estratègia ha consistit a estudiar diferents sistemes de calibratge amb l'objectiu d'estandarditzar la quantificació dels mètodes in vitro de diagnòstic d'aquesta mena d'al·lèrgies. Per a això, s'han avaluat les prestacions del calibratge homòleg, heteròleg i l'ús d'un patró intern, comparant les seues prestacions analítiques (relació senyal soroll, sensibilitat, reproductibilitat, etc.) amb el sistema de referència. Finalment, la validació de l'immunoassaig es va realitzar amb un conjunt de 101 mostres de sèrum de pacients i controls. Els resultats obtinguts han sigut comparats amb els obtinguts mitjançant les tècniques de referència, mostrant una millor sensibilitat, especificitat, precisió, i linealitat. La capacitat múltiplex de la tecnologia de disc compacte va permetre dur a terme paral·lelament estudis de reactivitat creuada enfront de diferents antibiòtics ß-lactáms esclarint el patró de reconeixement dels pacients. En aquesta línia de treball, l'ús d'altres estratègies de conjugació d'haptens ha resultat en la millora de la sensibilitat clínica de l'assaig, identificant nous epítops / [EN] ß-lactam antibiotics are one of the most widely used antimicrobials worldwide. However, up to 10% of the population reports having presented allergic symptoms derived from their consumption. Consequently, this portion of the population is considered "allergic". In the diagnosis of allergy to ß-lactam antibiotics there are several types of tests that serve to orient and confirm the presence of an allergy. These diagnostic methods are classified as in vivo and in vitro assays. Regarding in vivo tests, the most standardized tests are the provocation, prick and intradermal test. The aim of these assays is to observe the response produced by the different beta-lactam antibiotics in the patient after oral or cutaneous administration. Despite their wide use, these tests have their limitations, such as the risk of inducing severe systemic allergic reactions. Therefore, their practice requires specialized professionals for their indication, performance and interpretation. This requirement limit the performance of this type of test to specialized hospitals. The use and development of in vitro diagnostic techniques can overcome these disadvantages and allow the diagnosis of allergy without risks. In vitro assays are less invasive and therefore neither pose a risk of adverse reactions. Among the different serological and cellular tests that can be used, the detection of specific IgE is one of the most widespread due to its sensitivity and specificity. Current in vitro diagnostic systems use expensive and bulky analytical instrumentation and high-cost single-use materials, handled by qualified professionals. Therefore, such tests are performed only by allergy and/or clinical analysis services of hospitals or by companies specialized in clinical diagnostics. Consequently, there is a need to develop new diagnostic methods that can be implemented in all types of clinical laboratories at diverse levels of health care, meeting the requirements of sensitivity, speed, simplicity, multiplexing and portability at a reduced price. For this reason, the main objective of this doctoral thesis is the development of a multiplex immunoassay using compact disc technology for the detection and quantification of specific IgE levels to a wide variety of ß-lactam antibiotics in human serum samples. The most crucial limitations for the determination of multianalyte specific IgE by immunochemical methods are those related to sensitivity and selectivity. Hence, an important part of the thesis has been focused on the preparation and characterization of a pool of beta-lactam antigens, selection of immunoreagents, format and optimization of different critical parameters of the immunoassay. Another important aspect of the thesis has been focused on improving the reproducibility of the results. The strategy consisted of studying different calibration systems with the aim of standardizing the quantification of in vitro diagnostic tests for this type of allergy. To achieve that goal, the performance of homologous and heterologous calibration and the use of an internal standard have been evaluated, comparing their analytical performance (signal-to-noise ratio, sensitivity, reproducibility, etc.) with the reference system. Finally, the validation of the immunoassay was performed with a total of 101 serum samples from patients and controls. The results obtained have been compared with those obtained using the reference techniques, showing improved sensitivity, specificity, precision, and linearity. The multiplex capability of the compact disc technology allowed carrying out parallel cross-reactivity studies against different beta-lactam antibiotics both from the penicillin family and from other families, elucidating the recognition profile. Following this working line, the use of other hapten conjugation strategies improved clinical sensitivity of the assay by identifying new epitopes. / Juárez Rodriguez, MJ. (2022). Metodologías bioanalíticas para el diagnóstico in vitro de alergia a antibióticos ß-lactámicos [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/184011 / TESIS / Premios Extraordinarios de tesis doctorales
47

SPECTROSCOPIC STUDIES ON ACTIVE METALLO-ß-LACTAMASES

Aitha, Mahesh Kumar 27 August 2015 (has links)
No description available.
48

An analysis of the usage of antibiotics in the private health care sector : a managed health care approach / Renier Coetzee

Coetzee, Renier January 2004 (has links)
The most frequent intervention performed by physicians is the writing of a prescription. Modern medicine has been remarkably effective in managing diseases. Medicines play a fundamental role in the effectiveness, efficiency and responsiveness of health care systems. However, health care expenditure is a great cause for concern and many nations around the world struggle to contain rising health care costs. Pharmaceutical benefit management programmes such as pharmacoeconomics, drug utilisation review (DUR) and disease management have emerged as control tools to ensure cost effective selection and use of medicine. These managed care instruments are often used to determine whether new strategies or interventions, such as the implementation of a managed medicine reference price list, are appropriate and have "value". The general objective of this study was to investigate the influences of the implementation of a managed medicine reference price list on the usage and cost of antibiotic medicine in the private health care sector of South Africa. The research design used in this study was retrospective, non-experimental and quantitative. The data used for the analysis were obtained over a two-year study period (1 May 2001 to 31 April 2003) from the central medicine claims database of Medschem&. Data was analysed according to prevalence, cost and original (innovator) or generic medicine items. For the purpose of this study antibiotics referred to beta-lactams (penicillins, cephalosporins and "others"), erythromycin and other macrolides, tetracyclines, sulphonamides and combinations, quinolones, chloramphenicol and aminoglycosides. The results of the empirical investigation showed the total number of medicine items claimed during the study period amounted to 49098736 medicine items having a total expenditure of R7150344897.00. There was a decrease in the prevalence of original (innovator) products during the two-year period. The prevalence of generic products increased from 25.87% to 32.47%. A total of 4092495 antibiotic medicine items were claimed with a total cost of R526309279.43 representing 7.36% (n = R7150344897.00) of all pharmaceutical products purchased during the two-year period. Original antibiotics had a prevalence of 42.32%, while generic antibiotics constituted 57.68% of all antibiotic products claimed (n = 4092495). However, original (innovator) products contributed 62.32% and generic products 37.68% to the total cost of all antibiotics claimed. It was concluded that the beta-lactam antibiotics represented 56.99% of all antibiotics claimed (n = 4092495) and contributed 52.51% to the total antibiotic expenditure (n = R526309279.43) for the two-year period. The average cost of beta-lactam items ranged between R112.88 * 69.95 and R122.18 + 81.42. The Medschema Price List (MPL) was implemented in May 2001. The aim of this reference pricing system was to allocate a ceiling price to a group of drugs, which are similar in terms of composition, clinical efficacy, safety and quality, with the ultimate goal to reduce medicine expenditure. During the year of implementation of the MPL 62.24% of beta-lactam antibiotics claimed (n = 1303464) were MPL listed. These products contributed 43.25% to the total cost of all beta-lactam antibiotics (n = R157142778.38). Medical aid companies reimbursed R61649211.86 for penicillins claimed and MPL listed. If all penicillin products were claimed at the ceiling price set by the MPL, a cost saving of 2.79% could have been achieved. Cost analysis indicated that it is possible to reduce health care costs by implementing strategies with the aim to reduce medicine cost. Further research, however, is necessary and in this regard recommendations for further research were formulated. / Thesis (M.Pharm. (Pharmacy Practice))--North-West University, Potchefstroom Campus, 2005.
49

An analysis of the usage of antibiotics in the private health care sector : a managed health care approach / Renier Coetzee

Coetzee, Renier January 2004 (has links)
The most frequent intervention performed by physicians is the writing of a prescription. Modern medicine has been remarkably effective in managing diseases. Medicines play a fundamental role in the effectiveness, efficiency and responsiveness of health care systems. However, health care expenditure is a great cause for concern and many nations around the world struggle to contain rising health care costs. Pharmaceutical benefit management programmes such as pharmacoeconomics, drug utilisation review (DUR) and disease management have emerged as control tools to ensure cost effective selection and use of medicine. These managed care instruments are often used to determine whether new strategies or interventions, such as the implementation of a managed medicine reference price list, are appropriate and have "value". The general objective of this study was to investigate the influences of the implementation of a managed medicine reference price list on the usage and cost of antibiotic medicine in the private health care sector of South Africa. The research design used in this study was retrospective, non-experimental and quantitative. The data used for the analysis were obtained over a two-year study period (1 May 2001 to 31 April 2003) from the central medicine claims database of Medschem&. Data was analysed according to prevalence, cost and original (innovator) or generic medicine items. For the purpose of this study antibiotics referred to beta-lactams (penicillins, cephalosporins and "others"), erythromycin and other macrolides, tetracyclines, sulphonamides and combinations, quinolones, chloramphenicol and aminoglycosides. The results of the empirical investigation showed the total number of medicine items claimed during the study period amounted to 49098736 medicine items having a total expenditure of R7150344897.00. There was a decrease in the prevalence of original (innovator) products during the two-year period. The prevalence of generic products increased from 25.87% to 32.47%. A total of 4092495 antibiotic medicine items were claimed with a total cost of R526309279.43 representing 7.36% (n = R7150344897.00) of all pharmaceutical products purchased during the two-year period. Original antibiotics had a prevalence of 42.32%, while generic antibiotics constituted 57.68% of all antibiotic products claimed (n = 4092495). However, original (innovator) products contributed 62.32% and generic products 37.68% to the total cost of all antibiotics claimed. It was concluded that the beta-lactam antibiotics represented 56.99% of all antibiotics claimed (n = 4092495) and contributed 52.51% to the total antibiotic expenditure (n = R526309279.43) for the two-year period. The average cost of beta-lactam items ranged between R112.88 * 69.95 and R122.18 + 81.42. The Medschema Price List (MPL) was implemented in May 2001. The aim of this reference pricing system was to allocate a ceiling price to a group of drugs, which are similar in terms of composition, clinical efficacy, safety and quality, with the ultimate goal to reduce medicine expenditure. During the year of implementation of the MPL 62.24% of beta-lactam antibiotics claimed (n = 1303464) were MPL listed. These products contributed 43.25% to the total cost of all beta-lactam antibiotics (n = R157142778.38). Medical aid companies reimbursed R61649211.86 for penicillins claimed and MPL listed. If all penicillin products were claimed at the ceiling price set by the MPL, a cost saving of 2.79% could have been achieved. Cost analysis indicated that it is possible to reduce health care costs by implementing strategies with the aim to reduce medicine cost. Further research, however, is necessary and in this regard recommendations for further research were formulated. / Thesis (M.Pharm. (Pharmacy Practice))--North-West University, Potchefstroom Campus, 2005.

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