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Showing 141 to 150 of 151 (0.044 seconds)Spelling suggestions: "subject:"disinfectants"" "subject:"disinfectant's""
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Značaj intraoperativnog mehaničkog ispiranja u prevenciji kontaminacije kalema kod rekonstrukcije prednje ukrštene veze kolena / Importance of intraoperative mechanical irrigation in prevention of graft contamination in anterior cruciate ligament reconstructionRašović Predrag 26 September 2016 (has links)
<p>Intraoperativna kontaminacija autokalema tokom rekonstrukcije prednjeg ukrštenog ligamenta je i dalje tema koja je predmet stalne debate među ortpedskim hirurzima, a koja se preteţno odnosi na potrebu i način njenog tretmana. Ona nastaje kao posledica naseljavanja uzročnika kontaminacije iz vazduha, sa koţe i sluznica kako pacijenata tako i osoblja, kao i preko nesterilisanih ili nedovoljno sterilisanih instrumenata. Patogeni koji je izazivaju su identični uzročnicima koji izazivaju septični arthritis, pa se smatra jednim od faktora rizika za njegov nastanak. Septični arthritis predstavlja najčešću komplikaciju u artroskopskoj hirurgiji uopšte, a njegove posledice mogu bitno uticati na funkcionalni i mentalni status pacijenata. Zbog toga se smatra da je tretman intraoperativne kontaminacije autokalema tokom rekonstrukcije prednjeg ukrštenog ligamenta kolena mandatoran. Najčešće primenjivani agensi u tretmanu intraoperativne kontaminacije alokalema predstavljaju različite vrste antiseptičnih i antibiotskih solucija. I pored toga što intraoperativna irigacija fiziološkim rastvorom predstavlja jednu od najčešče primenjivanih procedura tokom hirurških operacija, u savremenoj literaturi je objavljen mali broj radova na temu primene ove procedure u tretmanu intraoperativne kontamninacije. Cilj ove studije je bio da pokaţe da se dekontaminacija autoklema tokom rekonstrukcije prednjeg ukrštenog ligamenta kolena moţe uspešno tretirati intraoperativnom mehaničkom irigacijom čistim fiziološkim rastvorom, kao i da odredi koja je količina fiziološkog rastvora dovoljna da izvrši potpunu dekontaminaciju autokalema. Jedan od ciljeva se odnosio na utvrđivanje uticaja faktora okruţenja na pojavu intraoperativne kontaminacije. Studija se sastojala iz dva dela- eksperimentalnog i kliničkog. Eksperimentalni deo studije je bio sproveden na Odeljenju za kliničku bakteriologiju Centra za mikrobiologiju Instituta za javno zdravlje Vojvodine i sastojao se iz pravljenja eksperimentalnog modela koji je imao za cilj da u in vitro uslovima obezbedi iste ili pribliţno iste uslove kao i operacionoj sali. On se sastojao od pedeset ispreparisanih i sterilisanih svinjskih tetiva dubokih pregibača prstiju koje su po svojim dimenzijama pribliţno odgovarale humanom prednjem ukrštenom ligamentu kolena. Tetive su potom bile kontaminirane unapred određenom koncetracijom najčešćeg uzročnika kontaminacije, a to je koagulaza negativan stafilokok ( ATCC 12228 Staphylococcus epidermidis). One su se potom mehanički ispirale sa 500 ml, 1000 ml, i 1500 ml fiziološkog rastvora, a nakon svakog ispiranja uzimao se bris. Brisevi su nakon toga bili zasejavani na krvni agar, a nakon 24h inkubacije su očitavane vrednosti brojanjem kolonija uzročnika. Rezultati eksperimentalnog dela pokazuju da je količina od 1500 ml fiziološkog rastvora dovoljna da izazove potpunu dekontaminaciju tetive. Rezultati eksperimentalnog dela su potom bili primenjivani u kliničkom delu studije koji je obuhvatao 200 ispitanika starosne dobi između 15-50 godina i koje je je bilo sprovedeno na Klinici za ortopedsku hirurgiju i traumatologiju Kliničkog centra Vojvodine. Kontrolnu grupu su činili onih 100 pacijenata kod kojih je mehaničko intraoperativno ispiranje autokalema neposredno pred njegovu implantaciju vršeno pomoću 500 ml fiziološkog rastvora, a ispitivanu grupu su činili drugih sto pacijenata kod kojih je isto to ispiranje izvršeno sa 1500 ml fiziološkog rastvora. Rezultati kliničkog dela studije jasno ukazuju da je količina od 1500 ml fiziološkog rastvora kojim se vrši intraoperativna mehanička irigacija dovoljna da izvrši potpunu dekonaminaciju autokalema kao i da stepen kontaminacije autokalema raste sa povećanjem vremena koje kalem provodi na vazduhu tokom obrade, što je u direktnoj vezi sa vremenskim trajanjem operacije i vrstom kalema koji se koristi za rekonstrukciju. Rezultati pokazuju da je rizik za nastanak kontaminacije autokalema u direktnoj vezi sa faktorima okruţenja, odnosno da se porastom broja ljudi u operacionoj sali, kao i redosledom operativnih procedura u toku jednog operativnog dana u smislu da operacije koje počinju kasnije na operativnom programu, povećava i procenat kontaminacije. Intraoperativna mehanička irigacija kontaminiranog autokalema se pokazala kao metoda koja se uspešno moţe koristiti u intaoperativnoj dekontaminaciji autokalema tokom rekonstrukcije prednje ukrštene veze kolena. Rezultati ove studije se mogu se primeniti i na druge asetne hirurgije i mogu posluţiti i daljim kliničkim istraţivanjima.</p> / <p>Intraoperative contamination of autograft during anterior cruciate ligament reconstruction still remains a topic for debate among orthopaedic surgeons mainly concerning the need and the way of its treatment. Graft contamination arises after pathogen settlement from the surrounding air, from skin and mucoses of patient and staff, as well as not enough sterilized instruments. Pathogens found in graft contamination are the same ones who are causes of septic arthritis, which is the most common complication in arthroscopic surgery in general. Consequences of septic arthritis usually leave a huge impact on patient’s mental and physical status. In modern surgery, it is mandatory to prevent potential auto-graft contamination by irrigation (during anterior cruciate ligament reconstruction in knee). Most commonly used agents for intraoperative auto-graft irrigation are variety of antiseptic and antibiotic solutions. Even though intraoperative irrigation with saline solution presents one of the most commonly used procedures during different surgical interventions in general, little is said in literature about its usage in auto-graft contamination. The aim of this study was to show that decontamination of auto-graft during anterior cruciate ligament reconstruction of the knee can be successfully done by mechanical irrigation with saline (0,9%) solution and also to define a precise quantity of saline for complete decontamination. Furthermore, effects of different factors in surroundings were inspected. The study consisted of two parts: experimental and clinical. Experimental part was conducted at the Department for clinical bacteriology, at Microbiology Centre at the Institute for public health of Vojvodina. It consisted in making the experimental model with in vitro conditions similar to or as the same as in the operating theatre. Experimental model was made of 50 preparated and sterilized pig tendons of deep finger flexors, which are similar dimensions as human anterior cruciate ligament of the knee. Then, the tendons were contaminated with previously defined concentration of most common cause of contamination which is coagulase negative staphylococcus (ATCC 12228 Staphylococcus epidermidis). Contaminated tendons were mechanicaly irrigated with 500ml, 1000ml and 1500ml saline solution. After each irrigation a swab was taken and put in blood agar to grow. Following 24h of incubation, bacterial colonies were counted. Results of experimental model show that 1500ml of saline solution is required for decontamination of tendon. Results of experimental model were used in clinical part of the study which was conducted at the Clinic for orthopaedic surgery and traumatology in Clinical Centre of Vojvodina. It comprised of 200 patients, who were 15-50 years old. Patients were divided in two equal groups: tested and control group. In control group mechanical irrigation of auto-graft was done prior to its implementation with 500ml saline solution, while in tested group 1500ml of saline was used for irrigation. Results of clinical part of the study show that intraoperative irrigation with 1500ml of saline solution is enough for complete decontamination of auto-graft. Furthermore, degree of auto-graft contamination rises with prolonged exposure time on surrounding air, with incrised number of people in the operating theatre and also with number and sequence of operations during the day. Intraoperative mechanical irrigation proved to be a sufficient method that can be used in intraoperative autograft decontamination during anterior cruciate ligament reconstruction. The results of this study can be applied to other aspects of the surgery and could be used and further clinical<br />studies.</p>
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Micobactérias de crescimento rápido de importância médica no Brasil: eficácia antimicrobiana de desinfetantes e sistema de esterilização por plasma / Rapidly growing mycobacteria of medical importance in Brazil: antimicrobial efficacy of disinfectants and plasma sterilization systemSilva, Juliano de Morais Ferreira 26 November 2010 (has links)
Práticas inadequadas de descontaminação, desinfecção e esterilização de materiais médico-hospitalares têm propiciado o surgimento de inúmeros surtos de infecções por \'Micobactérias de Crescimento Rápido\' (MCR), em todo o Brasil. Entre os anos de 2000 a 2008 foram relatados mais de 2000 casos confirmados de infecções por MCR, sendo que os procedimentos por vídeo se constituíram como os maiores veiculadores destes microrganismos. O aumento do emprego de dispositivos de natureza polimérica em procedimentos médico-cirúrgicos e ausência/não cumprimento de protocolos de processamento destes materiais podem estar envolvidos na disseminação, principalmente, pela capacidade de MCR produzirem e sobreviverem em sistemas de biofilmes. Desta forma, este trabalho teve como objetivo a avaliação da susceptibilidade de cepas de Mycobacterium abscessus subsp. bolettii (suspensão e biofilmes), causadoras ou não de surto, frente a desinfetantes químicos constituídos de: Glutaraldeído 2%, Ácido Peracético 0,2%, Peróxido de Hidrogênio 35%, Solução Alcoólica de Digluconato de Clorexidina 0,5%, Solução Aquosa de Clorexidina 0,2%, Compostos de Amônio Quaternário 1,2%, Iodo 1% e Fenol 5% e Sistemas de Esterilização por Plasma (RIE e ICP) empregando mistura gasosa O2-H2O2. Paralelamente, suportes poliméricos (PVC, PEAD, PP, PUR e PC) empregados como carreadores de MCR foram analisados por Espectroscopia Fotoacústica no Infravermelho (PAS-FTIR), Microscopia Eletrônica de Varredura (MEV), microanálise em Sistema Energy Dispersive Spectroscopy (EDS) e Perfilometria. Resultados destas investigações demonstraram a resistência das cepas de M. abscessus subsp. bolettii, isolada do surto ocorrido em Belém, frente a Glutaraldeído 2%, Solução Alcoólica de Digluconato de Clorexidina 0,5%, Solução Aquosa de Clorexidina 0,2%, Compostos de Amônio Quaternário 1,2% e Iodo 1%. Entretanto, estas cepas foram altamente sensíveis à Ácido Peracético 0,2%, Peróxido de Hidrogênio 35% e Fenol 5% e Sistema de Esterilização por Plasma (RIE). Em sistemas de biofilmes, as cepas padrão e M. abscessus subsp. bolletii se apresentaram resistentes a todos os desinfetantes estudados. Nos estudos envolvendo a integridade de polímeros frente a processos por plasma foram demonstradas modificações em nível superficial (oxidação e aumento da rugosidade) em todos os materiais processados, sendo que o sistema ICP apresentou-se mais agressivo em relação àquele empregando RIE. / Numerous outbreaks of Rapid Growth of Mycobacteria (RGM) have been associated with decontamination, disinfection and sterilization malpractices, in Brazil. Between 2000-2008 were reported more than 2,000 confirmed cases due to RGM infections, and the video procedures were considered to carry these microorganisms. The increased use of medical devices in surgical procedures may be involved in the RGM spreading by its ability to grow and survive in biofilm systems. The aim of this study was evaluate the susceptibility of Mycobacterium abscessus subsp. bolletii (outbreak and nonoutbreak strains) to chemical disinfectants: Glutaraldehyde 2%, Peracetic Acid 0.2%, Hydrogen Peroxide 35%, Chlorhexidine Digluconate 0.5%, Chlorhexidine 0.2%, Iodine 1%, Quaternary Ammonium Compounds 1.2%, and Phenol 5%. Plasma Sterilization Technologies (Reactive Ion Etching and Inductively Coupled Plasma) were also evaluated. Polymers employed in medical devices (Polyvinyl chloride, High-Density Polyethylene, Polycarbonate, Polypropylene, and Polyurethane) were analyzed by Photoacoustic Infrared Spectroscopy (PAS-FTIR), Scanning Electron Microscopy (SEM), System Energy Dispersive Spectroscopy (EDS) and Profilometry. The results have demonstrated the resistance of Mycobacterium abscessus subsp. bolletii isolated from the Belém (PA) outbreak considering chemical exposition to Glutaraldehyde 2%, Chlorhexidine Digluconate 0.5%, Chlorhexidine 0.2%, Quaternary Ammonium Compounds 1.2%, and Iodine 2%. However, these strains were highly sensitive to Peracetic Acid 0.2%, Hydrogen Peroxide 35%, and Phenol 5%. The M. abscessus subsp. bolletii strains have been presented resistant to all disinfectants studied, in biofilm systems. Studies involving polymer integrity demonstrated changes in surface (oxidation and roughness) on all processed materials, and the ICP system was more aggressive in contrast to Reactive Ion Etching.
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UV Disinfection between Concentric CylindersYe, Zhengcai 10 January 2007 (has links)
Outbreaks of food-born illness associated with the consumption of unpasteurized juice and apple cider have resulted in a rule published by the U.S. Food and Drug Administration (FDA) in order to improve the safety of juice products. The rule (21 CFR120) requires manufacturers of juice products to develop a Hazard Analysis and Critical Control Point (HACCP) plan and to achieve a 5-log reduction in the number of the most resistant pathogens. Ultraviolet (UV) disinfection is one of the promising methods to reach this 5-log reduction of pathogens. The absorption coefficients of juices typically vary from 10 to 40 1/cm and can be even higher depending on brand and processing conditions. Thin film reactors consisting of two concentric cylinders are suitable for inactivating pathogens in juices. When the two concentric cylinders are fixed, the flow pattern in the gap can be laminar Poiseuille flow or turbulent flow depending on flow rates. If the inner cylinder is rotating, and the rotating speed of the inner cylinder exceeds a certain value, the flow pattern can be either laminar or turbulent Taylor-Couette flow. UV disinfection between concentric cylinders in laminar Poiseuille flow, turbulent flow and both laminar and turbulent Taylor-Couette flow was investigated experimentally and numerically. This is the first systematic study done on UV disinfection between concentric cylinders in all three flow patterns. The present work provides new experimental data for pathogen inactivation in each of the three flow patterns. In addition, the present study constitutes the first systematic numerical CFD predictions of expected inactivation levels. Proper operating parameters and optimum gap widths for different flow patterns are suggested. It is concluded that laminar Poiseuille flow provides inferior (small) inactivation levels while laminar Taylor-Couette flow provides superior (large) inactivation levels. The relative inactivation levels are: laminar Poiseuille flow < turbulent flow < laminar Taylor-Couette flow.
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Effect of amine-based water treatment polymers on the formation of N-nitrosodimethylamine (NDMA) disinfection by-productPark, Sang Hyuck 17 January 2008 (has links)
In recent years, a compound N-nitrosodimethylamine (NDMA), a probable human carcinogen, has been identified as an emerging disinfection by-product (DBP) since its formation and detection were linked to chlorine-based disinfection processes in several water utilities in the U.S. and Canada. Numerous organic nitrogen compounds present in water may impact the formation of NDMA during disinfection. Amine-based water treatment polymers used as coagulants and flocculants have been suggested as potential NDMA precursors due to the presence of amine functional groups in their structures, as well as the possible presence of dimethylamine (DMA) residues in polymer products. To minimize the potential risk of NDMA associated with water treatment polymers, the mechanisms of how the polymers behave as NDMA precursors and their contribution to the overall NDMA formation under actual water treatment conditions need to be elucidated.
This research involved a systematic investigation to determine whether amine-based water treatment polymers contribute to NDMA formation under drinking water and wastewater treatment conditions, to probe the involved reaction mechanisms, and to develop strategies to minimize the polymers NDMA formation potential. The investigation included five research tasks: (1) General screening of NDMA formation potential of commonly used amine-based water treatment polymers, (2) NDMA formation from amine-based water treatment polymers under relevant water treatment conditions, (3) Probing the mechanisms of NDMA formation from polyamine and PolyDADMAC, (4) Effect of water treatment processes on NDMA formation from amine-based water treatment polymers, and (5) Developing strategies to reduce polymers NDMA formation potential. Direct chloramination or chlorination of high doses of polymers in deionized water at longer than typical contact time was used in the general screening of the NDMA formation potential of water treatment polymers and in the studies to identify reaction mechanisms. On the other hand, realistic dosages of chloramines and polymers and contact time were used in simulating representative water treatment conditions to evaluate the contribution of polymers to the overall NDMA formation in real systems. On the basis of the study results, strategies were developed to reduce the NDMA formation potential of amine-based water treatment polymers, which include modification of polymer structures and treatment parameters.
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Desenvolvimento de um biosensor para mensuração de deformações mecânicas em tecidos ósseosKaram, Leandro Zen 21 May 2015 (has links)
CNPQ / O presente trabalho tem como objetivo o desenvolvimento de um biosensor, utilizando redes de Bragg em fibras óticas, capaz de mensurar deformações em tecido ósseo. Inicialmente foram realizados testes de esterilização e desinfecção com sensores, após o processo completo, os sensores foram testados quanto a sua sensibilidade. Com isso os métodos de esterilização e desinfecção autoclave, óxido etileno, hipoclorito de sódio, cloramina T e ácido peracético, foram eficazes para eliminação e ou inativação dos microrganismos, sem que haja alterações no comportamento das FBGs. Com isso definem-se métodos aplicáveis para possíveis estudos, onde fibras óticas foram implantadas em animais in vivo para estudos de comportamento metabólico com a presença de materiais inorgânicos. Na continuidade dos trabalhos foram realizados testes de compatibilidade de fibras óticas inseridas no tecido subcutâneo de ratos. Baseado na análise descritiva dos cortes histológicos pode-se concluir que as fibras ópticas sem revestimento e com revestimento foram biocompatíveis quando implantadas em subcutâneo de ratos. Sendo assim, foi possível contemplar o desenvolvimento de um sensor baseado em redes de Bragg em fibras óticas para implantação direta no tecido ósseo. Posteriormente foram realizados testes-piloto para o desenvolvimento da metodologia de construção e implante no desenvolvimento de biosensores. Com todo o trabalho feito até à data, o desenvolvimento e construção de um biosensor que foi implantado in vivo foi possível. O biossensor foi fixado na região mandibular de um bovino quatro meses de idade. Uma semana após a implantação, os animais receberam diferentes tipos de alimentos e foi monitorizada durante a ingestão de alimentos. Com as deformações medidas foi possível a análise dos diferentes padrões mastigatórios e diferentes magnitudes de força e frequência mastigatória que o animal desempenhada durante o processo de mastigação. / This study aims to develop a biosensor using Bragg gratings in optical fibers, capable of measuring deformation in bone tissue for this took a lot of work. Initially sterilization and disinfection with sensors tests were performed after the entire process, the sensors were tested for their sensitivity. In the same study methods of sterilization and disinfection have been tested to assess its efficiency. Thus methods of sterilization and disinfection autoclave, ethylene oxide, sodium hypochlorite, chloramine T and peracetic acid were effective for removing or inactivating microorganisms and, without changes in the behavior of the FBGs. With this set up methods applicable for possible studies, where optical fibers are implanted in in vivo animal studies metabolic behavior in the presence of inorganic materials. Continuing the work was carried out optical fiber compatibility tests inserted in the subcutaneous tissue of rats. Based on the descriptive analysis of histological sections can be concluded that the optical fiber uncoated and coated were biocompatible when implanted in rat subcutaneous tissue. Thus it is possible to contemplate the development of a sensor based on Bragg gratings in optical fibers for direct implantation into the bone tissue. Following on from the work were carried out pilot tests for development of construction methodology and implant in biosensor development. With all the work done to date, the development and construction of a biosensor that was implanted in vivo was possible. The biosensor was fixed in the mandibular region of a bull four months old. A week after implantation, the animal received different types of food and was monitored during the intake of foods. With the deformations measured parse the different masticatory patterns and different magnitudes of force and masticatory frequency that the animal developed during the chewing process completing the objectives of this study.
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Atividade antibacteriana de antibióticos, de desinfetantes e de extrações vegetais sobre Salmonella padrão e Salmonelas isoladas em produtos de origem animalMaciel, Mônica Jachetti January 2015 (has links)
O gênero Salmonella constitui um problema para a saúde animal e humana. Com a finalidade de evitar a ocorrência da transmissão deste microrganismo e a interrupção da doença provocada por eles, deve-se utilizar desinfetantes e antibióticos. A exposição continuada a estes agentes pode resultar no surgimento de resistência microbiana. Tendo em vista este fenômeno, a pesquisa por novos agentes antimicrobianos a partir de extratos vegetais se faz necessária, pois existe a possibilidade de se encontrar substâncias eficazes contra a resistência de micro-organismos já disseminados no ambiente. Os objetivos deste estudo foram: monitorar a resistência das 134 amostras de Salmonella isoladas em produtos de origem animal frente a antibióticos comumente utilizados na rotina veterinária; testar a atividade dos desinfetantes frente às Salmonellas resistentes; testar a hipótese de resistência cruzada entre grupos antibióticos e desinfetantes; avaliar a atividade bactericida de extratos de plantas medicinais nativas no Rio Grande do Sul sobre salmonelas padrão; avaliar a atividade antibacteriana do macerado hidroalcoólico de Achyrocline satureioides frente às salmonelas resistentes; fazer prospecção fitoquímica do macerado hidroalcoólico e do decocto de Achyrocline satureioides, Realizou-se o teste de sensibilidade a antibióticos frente a 134 amostras de Salmonella spp. isoladas em produtos de origem animal. Cinquenta e uma (51) salmonelas foram resistentes a pelo menos um antibiótico. Após, utilizou-se o teste de suspensão da avaliação quantitativa da atividade bactericida de desinfetantes. Foram testados os desinfetantes cloreto de cetil trimetilamônio (amônia quaternária), digluconato de clorexidina (clorexidina), hipoclorito de sódio e iodóforo, em quatro concentrações frente salmonelas resistentes, nos tempos 5, 15 e 60 minutos, densidade populacional 107 UFC/ mL. O iodóforo e o hipoclorito de sódio inativaram os isolados na maior parte dos experimentos. Porém, cloreto de cetil trimetilamônio (amônia quaternária) e digluconato de clorexidina (clorexidina) mesmo nas maiores concentrações do desinfetante, houveram micro-organismos resistentes. Pode-se perceber que não houveram relações concomitantes de resistência entre antibióticos e desinfetantes, levando-se em consideração todas as variáveis testadas. Na triagem inicial da atividade antibacteriana das plantas medicinais, utilizou-se a proporção de 10 g de planta para 100 mL do líquido extrator, em 8 e 24 horas, densidade populacional de Salmonella Choleraesuis (ATCC 10.708) 107, 106 e 105 UFC/ mL e formas decocção e maceração hidroalcoólica das plantas Achyrocline satureioides, Bidens pilosa, Conyza bonariensis, Jacaranda micrantha, Myrciaria cuspidata e Smilax cognata. A. satureioides, como macerado hidroalcoólico apresentou inativação nos tempos 8 e 24 horas, mostrando maior redução logarítmica. A. satureioides no macerado hidroalcoólico foi testada frente a 51 salmonelas resistentes. Observou-se que quanto maior o tempo de contato, nas menores densidades populacionais, maior foi o número de inativações. A atividade antibactericida do macerado hidroalcoólico de A. satureioides sugere o seu uso como ingrediente antisséptico em pomadas para uso animal ou humano, ou ser empregado na imersão de utensílios e partes removíveis de maquinários das indústrias alimentícias, frigoríficos, tendo como objetivo promover a desinfecção destes insumos. A prospecção fitoquímica realizada com o decocto e com o macerado hidroalcoólico de A. satureioides detectou a presença de compostos fenólicos, taninos hidrolisáveis e condensados, flavonóis e saponinas. O decocto de A. satureioides, diferentemente do macerado hidroalcoólico, não apresentou taninos hidrolisáveis e saponinas. / The genus Salmonella constitutes a problem for animal and human health. In order to prevent the transmission of this organism and the interruption of the disease caused by them, you should use disinfectants and antibiotics. Continued exposure to these agents can result in the emergence of microbial resistance. In view of this phenomenon, the search for new antimicrobials from plant extracts is necessary, because there is a possibility to find effective substances against the resistance of microorganisms already disseminated in the environment. The objectives of this study were: to monitor the resistance of 134 samples of Salmonella isolated in products of animal origin in front of antibiotics commonly used in veterinary routine; test the activity of disinfectants against the salmonellas resistant; test the hypothesis of cross-resistance between antibiotics and disinfectants; evaluate the bactericidal activity of extracts of medicinal plants native to the Rio Grande do Sul on Salmonella standard; evaluate the antibacterial activity of hydroalcoholic macerate to Achyrocline satureioides to Salmonella resistant; do the hydroalcoholic macerate phytochemical prospecting and to Achyrocline satureioides vegetable water, antibiotic sensitivity testing in front of 134 samples of Salmonella spp. isolated in products of animal origin. Fifty-one (51) Salmonella were resistant to at least one antibiotic. After, we used the suspension test of quantitative evaluation of bactericidal activity of disinfectants. Have been tested the disinfectants cetyl trimetilamônio chloride (quaternary ammonia), chlorhexidine digluconate (chlorhexidine), sodium hypochlorite, iodophor in four concentrations Salmonella resistant front, 5 times, 15 and 60 minutes, population density 107 CFU/ mL. The iodophor and sodium hypochlorite inactivated isolates in most experiments. However, cetyl trimetilamônio chloride (quaternary ammonia) and chlorhexidine digluconate (chlorhexidine) even in the largest concentrations of disinfectant, there were resistant microorganisms. One can notice that there were no concurrent relationships of resistance between antibiotics and disinfectants, taking into account all the variables tested. In the initial screening of antibacterial activity of medicinal plants, the proportion of 10 g of plant for 100 mL of liquid Extractor, in 8 and 12:00 hour, population density of Salmonella Choleraesuis (ATCC 10,708) 107, 106 and 105 CFU/ mL decoction and hydroalcoholic maceration and the plants Achyrocline satureioides, Bidens pilosa, Conyza bonariensis, Jacaranda micrantha, Myrciaria cuspidata and Smilax cognate. A. satureioides hydroalcoholic macerate as presented 8 and 12 hour in inactivation, showing greater logarithmic reduction. A. satureioides in hydroalcoholic macerate has been tested in front of Salmonella resistant 51. It was observed that the longer the time of contact, the smallest population densities, higher number of inactivation. The antibacterial activity of hydroalcoholic macerate of A. satureioides suggests its use as an antiseptic ingredient in ointments for human or animal use, or be employed in the immersion of utensils and removable parts of machinery of food industries, refrigerators, aiming to promote the disinfection of these inputs. The phytochemical held prospecting with the vegetable water and hydroalcoholic macerate of A. satureioides detected the presence of phenolic compounds, hydrolysable and condensed tannins, flavonols and saponins. The vegetable water of A. satureioides, unlike the hydroalcoholic macerate, hydrolysable tannins and failed to provide saponins.
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Atividade antibacteriana de antibióticos, de desinfetantes e de extrações vegetais sobre Salmonella padrão e Salmonelas isoladas em produtos de origem animalMaciel, Mônica Jachetti January 2015 (has links)
O gênero Salmonella constitui um problema para a saúde animal e humana. Com a finalidade de evitar a ocorrência da transmissão deste microrganismo e a interrupção da doença provocada por eles, deve-se utilizar desinfetantes e antibióticos. A exposição continuada a estes agentes pode resultar no surgimento de resistência microbiana. Tendo em vista este fenômeno, a pesquisa por novos agentes antimicrobianos a partir de extratos vegetais se faz necessária, pois existe a possibilidade de se encontrar substâncias eficazes contra a resistência de micro-organismos já disseminados no ambiente. Os objetivos deste estudo foram: monitorar a resistência das 134 amostras de Salmonella isoladas em produtos de origem animal frente a antibióticos comumente utilizados na rotina veterinária; testar a atividade dos desinfetantes frente às Salmonellas resistentes; testar a hipótese de resistência cruzada entre grupos antibióticos e desinfetantes; avaliar a atividade bactericida de extratos de plantas medicinais nativas no Rio Grande do Sul sobre salmonelas padrão; avaliar a atividade antibacteriana do macerado hidroalcoólico de Achyrocline satureioides frente às salmonelas resistentes; fazer prospecção fitoquímica do macerado hidroalcoólico e do decocto de Achyrocline satureioides, Realizou-se o teste de sensibilidade a antibióticos frente a 134 amostras de Salmonella spp. isoladas em produtos de origem animal. Cinquenta e uma (51) salmonelas foram resistentes a pelo menos um antibiótico. Após, utilizou-se o teste de suspensão da avaliação quantitativa da atividade bactericida de desinfetantes. Foram testados os desinfetantes cloreto de cetil trimetilamônio (amônia quaternária), digluconato de clorexidina (clorexidina), hipoclorito de sódio e iodóforo, em quatro concentrações frente salmonelas resistentes, nos tempos 5, 15 e 60 minutos, densidade populacional 107 UFC/ mL. O iodóforo e o hipoclorito de sódio inativaram os isolados na maior parte dos experimentos. Porém, cloreto de cetil trimetilamônio (amônia quaternária) e digluconato de clorexidina (clorexidina) mesmo nas maiores concentrações do desinfetante, houveram micro-organismos resistentes. Pode-se perceber que não houveram relações concomitantes de resistência entre antibióticos e desinfetantes, levando-se em consideração todas as variáveis testadas. Na triagem inicial da atividade antibacteriana das plantas medicinais, utilizou-se a proporção de 10 g de planta para 100 mL do líquido extrator, em 8 e 24 horas, densidade populacional de Salmonella Choleraesuis (ATCC 10.708) 107, 106 e 105 UFC/ mL e formas decocção e maceração hidroalcoólica das plantas Achyrocline satureioides, Bidens pilosa, Conyza bonariensis, Jacaranda micrantha, Myrciaria cuspidata e Smilax cognata. A. satureioides, como macerado hidroalcoólico apresentou inativação nos tempos 8 e 24 horas, mostrando maior redução logarítmica. A. satureioides no macerado hidroalcoólico foi testada frente a 51 salmonelas resistentes. Observou-se que quanto maior o tempo de contato, nas menores densidades populacionais, maior foi o número de inativações. A atividade antibactericida do macerado hidroalcoólico de A. satureioides sugere o seu uso como ingrediente antisséptico em pomadas para uso animal ou humano, ou ser empregado na imersão de utensílios e partes removíveis de maquinários das indústrias alimentícias, frigoríficos, tendo como objetivo promover a desinfecção destes insumos. A prospecção fitoquímica realizada com o decocto e com o macerado hidroalcoólico de A. satureioides detectou a presença de compostos fenólicos, taninos hidrolisáveis e condensados, flavonóis e saponinas. O decocto de A. satureioides, diferentemente do macerado hidroalcoólico, não apresentou taninos hidrolisáveis e saponinas. / The genus Salmonella constitutes a problem for animal and human health. In order to prevent the transmission of this organism and the interruption of the disease caused by them, you should use disinfectants and antibiotics. Continued exposure to these agents can result in the emergence of microbial resistance. In view of this phenomenon, the search for new antimicrobials from plant extracts is necessary, because there is a possibility to find effective substances against the resistance of microorganisms already disseminated in the environment. The objectives of this study were: to monitor the resistance of 134 samples of Salmonella isolated in products of animal origin in front of antibiotics commonly used in veterinary routine; test the activity of disinfectants against the salmonellas resistant; test the hypothesis of cross-resistance between antibiotics and disinfectants; evaluate the bactericidal activity of extracts of medicinal plants native to the Rio Grande do Sul on Salmonella standard; evaluate the antibacterial activity of hydroalcoholic macerate to Achyrocline satureioides to Salmonella resistant; do the hydroalcoholic macerate phytochemical prospecting and to Achyrocline satureioides vegetable water, antibiotic sensitivity testing in front of 134 samples of Salmonella spp. isolated in products of animal origin. Fifty-one (51) Salmonella were resistant to at least one antibiotic. After, we used the suspension test of quantitative evaluation of bactericidal activity of disinfectants. Have been tested the disinfectants cetyl trimetilamônio chloride (quaternary ammonia), chlorhexidine digluconate (chlorhexidine), sodium hypochlorite, iodophor in four concentrations Salmonella resistant front, 5 times, 15 and 60 minutes, population density 107 CFU/ mL. The iodophor and sodium hypochlorite inactivated isolates in most experiments. However, cetyl trimetilamônio chloride (quaternary ammonia) and chlorhexidine digluconate (chlorhexidine) even in the largest concentrations of disinfectant, there were resistant microorganisms. One can notice that there were no concurrent relationships of resistance between antibiotics and disinfectants, taking into account all the variables tested. In the initial screening of antibacterial activity of medicinal plants, the proportion of 10 g of plant for 100 mL of liquid Extractor, in 8 and 12:00 hour, population density of Salmonella Choleraesuis (ATCC 10,708) 107, 106 and 105 CFU/ mL decoction and hydroalcoholic maceration and the plants Achyrocline satureioides, Bidens pilosa, Conyza bonariensis, Jacaranda micrantha, Myrciaria cuspidata and Smilax cognate. A. satureioides hydroalcoholic macerate as presented 8 and 12 hour in inactivation, showing greater logarithmic reduction. A. satureioides in hydroalcoholic macerate has been tested in front of Salmonella resistant 51. It was observed that the longer the time of contact, the smallest population densities, higher number of inactivation. The antibacterial activity of hydroalcoholic macerate of A. satureioides suggests its use as an antiseptic ingredient in ointments for human or animal use, or be employed in the immersion of utensils and removable parts of machinery of food industries, refrigerators, aiming to promote the disinfection of these inputs. The phytochemical held prospecting with the vegetable water and hydroalcoholic macerate of A. satureioides detected the presence of phenolic compounds, hydrolysable and condensed tannins, flavonols and saponins. The vegetable water of A. satureioides, unlike the hydroalcoholic macerate, hydrolysable tannins and failed to provide saponins.
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Micobactérias de crescimento rápido de importância médica no Brasil: eficácia antimicrobiana de desinfetantes e sistema de esterilização por plasma / Rapidly growing mycobacteria of medical importance in Brazil: antimicrobial efficacy of disinfectants and plasma sterilization systemJuliano de Morais Ferreira Silva 26 November 2010 (has links)
Práticas inadequadas de descontaminação, desinfecção e esterilização de materiais médico-hospitalares têm propiciado o surgimento de inúmeros surtos de infecções por \'Micobactérias de Crescimento Rápido\' (MCR), em todo o Brasil. Entre os anos de 2000 a 2008 foram relatados mais de 2000 casos confirmados de infecções por MCR, sendo que os procedimentos por vídeo se constituíram como os maiores veiculadores destes microrganismos. O aumento do emprego de dispositivos de natureza polimérica em procedimentos médico-cirúrgicos e ausência/não cumprimento de protocolos de processamento destes materiais podem estar envolvidos na disseminação, principalmente, pela capacidade de MCR produzirem e sobreviverem em sistemas de biofilmes. Desta forma, este trabalho teve como objetivo a avaliação da susceptibilidade de cepas de Mycobacterium abscessus subsp. bolettii (suspensão e biofilmes), causadoras ou não de surto, frente a desinfetantes químicos constituídos de: Glutaraldeído 2%, Ácido Peracético 0,2%, Peróxido de Hidrogênio 35%, Solução Alcoólica de Digluconato de Clorexidina 0,5%, Solução Aquosa de Clorexidina 0,2%, Compostos de Amônio Quaternário 1,2%, Iodo 1% e Fenol 5% e Sistemas de Esterilização por Plasma (RIE e ICP) empregando mistura gasosa O2-H2O2. Paralelamente, suportes poliméricos (PVC, PEAD, PP, PUR e PC) empregados como carreadores de MCR foram analisados por Espectroscopia Fotoacústica no Infravermelho (PAS-FTIR), Microscopia Eletrônica de Varredura (MEV), microanálise em Sistema Energy Dispersive Spectroscopy (EDS) e Perfilometria. Resultados destas investigações demonstraram a resistência das cepas de M. abscessus subsp. bolettii, isolada do surto ocorrido em Belém, frente a Glutaraldeído 2%, Solução Alcoólica de Digluconato de Clorexidina 0,5%, Solução Aquosa de Clorexidina 0,2%, Compostos de Amônio Quaternário 1,2% e Iodo 1%. Entretanto, estas cepas foram altamente sensíveis à Ácido Peracético 0,2%, Peróxido de Hidrogênio 35% e Fenol 5% e Sistema de Esterilização por Plasma (RIE). Em sistemas de biofilmes, as cepas padrão e M. abscessus subsp. bolletii se apresentaram resistentes a todos os desinfetantes estudados. Nos estudos envolvendo a integridade de polímeros frente a processos por plasma foram demonstradas modificações em nível superficial (oxidação e aumento da rugosidade) em todos os materiais processados, sendo que o sistema ICP apresentou-se mais agressivo em relação àquele empregando RIE. / Numerous outbreaks of Rapid Growth of Mycobacteria (RGM) have been associated with decontamination, disinfection and sterilization malpractices, in Brazil. Between 2000-2008 were reported more than 2,000 confirmed cases due to RGM infections, and the video procedures were considered to carry these microorganisms. The increased use of medical devices in surgical procedures may be involved in the RGM spreading by its ability to grow and survive in biofilm systems. The aim of this study was evaluate the susceptibility of Mycobacterium abscessus subsp. bolletii (outbreak and nonoutbreak strains) to chemical disinfectants: Glutaraldehyde 2%, Peracetic Acid 0.2%, Hydrogen Peroxide 35%, Chlorhexidine Digluconate 0.5%, Chlorhexidine 0.2%, Iodine 1%, Quaternary Ammonium Compounds 1.2%, and Phenol 5%. Plasma Sterilization Technologies (Reactive Ion Etching and Inductively Coupled Plasma) were also evaluated. Polymers employed in medical devices (Polyvinyl chloride, High-Density Polyethylene, Polycarbonate, Polypropylene, and Polyurethane) were analyzed by Photoacoustic Infrared Spectroscopy (PAS-FTIR), Scanning Electron Microscopy (SEM), System Energy Dispersive Spectroscopy (EDS) and Profilometry. The results have demonstrated the resistance of Mycobacterium abscessus subsp. bolletii isolated from the Belém (PA) outbreak considering chemical exposition to Glutaraldehyde 2%, Chlorhexidine Digluconate 0.5%, Chlorhexidine 0.2%, Quaternary Ammonium Compounds 1.2%, and Iodine 2%. However, these strains were highly sensitive to Peracetic Acid 0.2%, Hydrogen Peroxide 35%, and Phenol 5%. The M. abscessus subsp. bolletii strains have been presented resistant to all disinfectants studied, in biofilm systems. Studies involving polymer integrity demonstrated changes in surface (oxidation and roughness) on all processed materials, and the ICP system was more aggressive in contrast to Reactive Ion Etching.
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Étude de la diversité, de la persistance et de la formation du biofilm chez les souches de Listeria monocytogenes dans des abattoirs de porc au QuébecCherifi, Tamazight 09 1900 (has links)
Listeria monocytogenes est une bactérie Gram positif, largement présente dans différents types d’environnement, qui peut causer une maladie rare, mais grave, la listériose. Les caractéristiques de cette bactérie, sa pathogénie et sa capacité à survivre dans des conditions difficiles, font d’elle une bactérie qui suscite des inquiétudes particulièrement dans les industries agroalimentaires. Par son caractère ubiquitaire, elle se retrouve aussi dans ce type d’environnement et, par conséquent, peut contaminer les aliments. La persistance de L. monocytogenes dans l’environnement des industries agroalimentaires est un phénomène établi, mais les mécanismes qui y conduisent font encore aujourd’hui débat. Par ailleurs, alors qu’une réglementation stricte a été mise en place dans les industries de transformation de produits prêt-à-manger en rapport avec les risques de contamination par L. monocytogenes, il n’y a, à ce jour que peu d’information disponible au Québec sur la présence de cette bactérie en amont de cette production, soit au niveau de la viande crue. Les objectifs de ce projet de thèse visent, d’une part, à étudier la distribution, la diversité et la persistance des souches de L. monocytogenes dans l’environnement de quatre abattoirs de porcs au Québec; de vérifier la présence de génotypes identifiés comme persistants dans les aliments et les cas de listériose humaine et d’établir les mécanismes de persistance de la bactérie dans l’environnement de ces industries.
Les résultats de ce projet de thèse ont montré qu’après les opérations de nettoyage et de désinfection, la composition de la contamination par L. monocytogenes selon les abattoirs et les secteurs était significativement différente. Ainsi, deux abattoirs ont montré une contamination plus élevée comparativement à un autre abattoir. Une importante diversité de souches de L. monocytogenes est présente dans l’environnement des abattoirs et des usines de découpe de viande. Cette diversité était généralement similaire entre les abattoirs sauf pour un seul abattoir qui a montré une diversité significativement plus élevée. La diversité des souches n’était pas variable en fonction de l’étape du processus d’abattage, soulignant la tolérance de ces souches aux stress spécifiques des différents environnements de ces industries. Cette étude a montré que la présence de souches persistantes de L. monocytogenes était plus importante au niveau des étapes post-éviscération de l’abattage, et particulièrement en découpe. Dans ces conditions, le risque de contamination des produits est très présent. La comparaison des caractéristiques génotypiques des souches persistantes avec celles des souches isolées des aliments transformés et des cas de listériose humaine a montré un lien significatif entre ces souches. La relation entre la fréquence importante de détections de souches présentant ces profils au Québec, mais aussi au Canada et leur persistance dans les nombreux environnements agroalimentaires autres que celui des abattoirs et des salles de découpe des viandes reste à être documentée pour une meilleure compréhension de l’origine des listérioses humaines.
L’étude des différents mécanismes de persistance des souches de L. monocytogenes réalisée au cours de cette thèse a montré que la présence de gènes de résistance aux ammoniums quaternaires (QACs) dans certaines souches est particulièrement associée au caractère de persistance, alors qu’aucune différence dans la capacité à former du biofilm n’a été mise en évidence entre les souches persistantes et celles non persistantes. L’absence de caractère génétique évident et spécifique à la capacité de former le biofilm rend difficile l’association de ce dernier à la persistance des souches de L. monocytogenes. Néanmoins, le biofilm reste un phénomène pouvant expliquer en partie la persistance de L. monocytogenes. Par ailleurs l’étude de l’impact de la concentration en nutriments sur le biofilm de L. monocytogenes a montré qu’en conditions de limitation en nutriments, la structure du biofilm de L. monocytogenes était en forme de nid d’abeille attribuée à la présence d’une plus grande quantité d’ADN extracellulaire. Cette structure confère une meilleure stabilité au biofilm ce qui explique une plus forte biomasse.
Nous avons également démontré ici une association du genre Listeria avec d’autres genres bactériens de l’écosystème microbien résiduel de la surface de l’environnement de découpe des viandes. Ainsi, la co-occurrence de Listeria spp. avec Pseudomonas spp. laisse croire à la présence d’une interaction entre les espèces de ces genres. D’autre part, la présence de plusieurs genres dont Sphingomonas, Paracoccus et Caulobacter est négativement corrélée avec celle de Listeria spp. Ceci ouvre la voie à des études portant sur les interactions spécifiques entre ces genres bactériens et Listeria, et particulièrement l’espèce monocytogenes. L’ensemble de ces études éclaire le phénomène de persistance chez L. monocytogenes : il ne s’agit pas d’un mécanisme unique pour toutes les souches présentant ce caractère mais plutôt le résultat d’une sélection basée sur la résistance aux antimicrobiens, la capacité à former du biofilm en interaction avec d’autres espèces bactériennes, le premier pouvant être nécessaire et suffisant. Cette sélection peut être favorisée également par l’existence d’une niche écologique favorable telle que des endroits difficiles d’accès au nettoyage et à la désinfection.
L’importance de considérer les risques de contamination de L. monocytogenes en amont de la production des produits prêts à manger à base de viande a été démontrée dans ce travail, dans la mesure où, à partir d’une grande diversité de souches présentes dans ce secteur, émerge une population présentant des profils génotypiques similaires à ceux retrouvés dans les aliments et les cas de listériose humaine. Cette étude permettra donc une reconsidération de l’importance d’une surveillance cohérente de L. monocytogenes en amont de la production de prêt à manger, afin de limiter ainsi les risques de contamination des matières premières des industries de transformation. / Listeria monocytogenes is a Gram-positive bacterium widely distributed in various types
of environment and can cause listeriosis, a rare but serious disease. The characteristics of this bacterium related to its pathogenesis and its ability to survive in harsh environments make it a harmful bacterium especially in the agri-food industries. Indeed, being an ubiquitous bacterium, it is also found in this type of environment leading to food contamination. The persistence of L. monocytogenes in the environmental food processing plants is a well-known phenomenon, but the mechanisms of persistence are still debated today. In addition, while strict regulations have been established in ready-to-eat industries in relation to the risk of contamination by L. monocytogenes, there is currently no information on the presence of this bacterium in early steps of pork product production in Canada. The aims of this project were 1) to investigate the distribution, diversity and persistence of L. monocytogenes isolates across slaughtering and cutting processes in four slaughterhouses, 2) to evaluate the association between the persistence attribute of L. monocytogenes genotypes and their detection in food and human listeriosis cases and 3) to study mechanisms involved in the persistence of L. monocytogenes, including biofilm formation ability, resistance to disinfectants and interaction with other bacteria from meat conveyor surfaces.
Results showed that after cleaning and disinfection operations, the composition of L.monocytogenes contamination according to slaughterhouses and sectors was significantly different. Thus, two slaughterhouses showed higher contamination compared to another slaughterhouse. Results have shown also that a significant diversity of L. monocytogenes strains was present in the environment of slaughterhouses and cutting areas. Overall, the diversity did not vary depending on slaughterhouses except for one slaughterhouse which exhibited a higher strain diversity. According to the stage of slaughter process, this diversity was not variable underlying the tolerance of these strains to the stress encountered within the different environments in these plants. This study showed that the presence of persistent strains of L. monocytogenes in the post-evisceration stages was greater, particularly in cutting areas, suggesting a possibility of repeated contamination of meat products.
When comparing the genetic profiles of persistent strains with strains isolated from processed and ready-to-eat foods and human listeriosis cases, a significant association was found, suggesting a persistence in other processing environments in addition to slaughterhouses.
Our studies of the different persistence mechanisms of L. monocytogenes strains have shown that Quaternary ammonium compounds (QAC) resistance genes are particularly associated with persistent strains while no difference in the ability to generate a biofilm was observed between persistent and non-persistent strains. The lack of obvious genetic attribute(s) and specificity in the various isolates biofilm formation ability makes it difficult to solely attribute to the latter to the persistence of L. monocytogenes strains. Nevertheless, biofilm remains a phenomenon that can partly explain the persistence of L. monocytogenes. Furthermore, the study of the co-occurrence of Listeria spp. with other bacterial genera of the cutting surfaces microflora showed that Listeria spp. co-occurs with Pseudomonas spp. suggesting a possible interaction between species from these two genera. In the other hand, several other genera, of which Sphingomonas, Paracoccus and Caulobacter, negatively affect Listeria, which would suggest that these bacteria inhibit or limit the growth of the genus Listeria, and potentially L. monocytogenes, by competition for colonizing this habitat or, more particularly, for nutrients.
Studies of these mechanisms have demonstrated that persistence of L. monocytogenes could not be explained by a single mechanism for all strains but through a selection phenomenon based on one or several attributes such as antimicrobial resistance, biofilm formation, and capacity to interact with other bacterial species. This selection pressure can also be affected by the existence of a favorable ecological niche such as difficult areas to access to disinfect.
In conclusion, the importance of contamination risks by L. monocytogenes in the pig slaughterhouses was demonstrated by the presence of a great diversity of strains at this level but, more importantly, by the finding that the likelihood to recover persistent strains may be enhanced through resistance to industrials disinfectants and, to a lesser extent, by biofilm formation. These persistent strains shared similar genetic profiles to those found in foods and human listeriosis. This study supports the importance of a consistent and comprehensive monitoring of L. monocytogenes upstream of the ready-to-eat production, as a tool for limiting the risk of contamination of the raw materials of the processing industries.
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Development of Sensitive In Vitro Assays to Assess the Ocular Toxicity Potential of Chemicals and Ophthalmic ProductsMcCanna, David January 2009 (has links)
The utilization of in vitro tests with a tiered testing strategy for detection of mild ocular irritants can reduce the use of animals for testing, provide mechanistic data on toxic effects, and reduce the uncertainty associated with dose selection for clinical trials. The first section of this thesis describes how in vitro methods can be used to improve the prediction of the toxicity of chemicals and ophthalmic products. The proper utilization of in vitro methods can accurately predict toxic threshold levels and reduce animal use in product development. Sections two, three and four describe the development of new sensitive in vitro methods for predicting ocular toxicity. Maintaining the barrier function of the cornea is critical for the prevention of the penetration of infections microorganisms and irritating chemicals into the eye. Chapter 2 describes the development of a method for assessing the effects of chemicals on tight junctions using a human corneal epithelial and canine kidney epithelial cell line. In Chapter 3 a method that uses a primary organ culture for assessing single instillation and multiple instillation toxic effects is described. The ScanTox system was shown to be an ideal system to monitor the toxic effects over time as multiple readings can be taken of treated bovine lenses using the nondestructive method of assessing for the lens optical quality. Confirmations of toxic effects were made with the utilization of the viability dye alamarBlue. Chapter 4 describes the development of sensitive in vitro assays for detecting ocular toxicity by measuring the effects of chemicals on the mitochondrial integrity of bovine cornea, bovine lens epithelium and corneal epithelial cells, using fluorescent dyes.
The goal of this research was to develop an in vitro test battery that can be used to accurately predict the ocular toxicity of new chemicals and ophthalmic formulations. By comparing the toxicity seen in vivo animals and humans with the toxicity response in these new in vitro methods, it was demonstrated that these in vitro methods can be utilized in a tiered testing strategy in the development of new chemicals and ophthalmic formulations.
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