Cryopreservation is the preservation of biomaterials at extremely low temperatures. It is the only alternative for long-term storage of high quality biomaterials, with applications to biobanking and transplant medicine. Cryopreservation success revolves around the control of ice formation, which is known to be harmful. Ice formation is a path-dependent phenomenon, affected by the thermal history and presence of nucleation promotors. Cryoprotective agents (CPAs) are commonly added to the biomaterial to be preserved, in order to suppress ice formation and inhibit its growth during the cryopreservation protocol. Ice-free cryopreservation can be achieved in large-size systems when the biomaterial is loaded with a high CPA concentration solution and cooled rapidly, in a process that is known as vitrification (vitreous means glassy in Latin). During vitrification, the CPA viscosity increases exponentially with decreasing temperature, while the material is cooled to deep cryogenic temperatures faster than the typical time scale for crystallization. The material can potentially be stored indefinitely at such low temperatures. Large-size vitrification is associated with three competing needs on the CPA concentration. Since the cooling rate at the center of the specimen decreases with the increasing specimen size due to the scaling conductive resistance, higher CPA concentrations may be required to suppress crystallization in larger specimens. Higher CPA concentration generally requires lower cooling rates to avoid ice crystallization. On the other hand, since CPAs are potentially toxic, the lowest possible CPA concentration is required to maintain viability and facilitate functional recovery. The decrease in CPA concentration combined with an increase in cooling rates may intensify thermo-mechanical stress due to non-uniform thermal contraction to the point of structural destruction. Essentially, successful cryopreservation represents the outcome of an optimization problem on the composition and concentration of the CPA cocktail. The work presented in this thesis combines an experimental study on the thermal conductivity of relevant materials, and a theoretical study to identify the effects of the measured values on cryopreservation protocols. The unique contributions presented as the initial stage of the experimental study are: (i) the modification of the cryomacroscope and creation of an experimental program to make thermal conductivity measurements of CPA based on the existing transient hot wire technique, (ii) to develop a protocol for making thermal conductivity measurements during rewarming portion of the cryoprotocol, and (iii), to begin generating a data bank of thermal conductivity of CPA and materials used in cryopreservation. Thermal conductivity measurements are presented for the CPA Dimethyl Sulfoxide (DMSO), over a concentration range of 2M to 10M, in a temperature range of -180°C to 25°C. Samples of 2M to 6M DMSO were found to crystallize at quasi-steady cooling rates, while samples of 7.05 to 10M were found to vitrify. Thermal conductivities of the crystallized and vitrified material reach a tenfold difference at -180°C. The quality of measurements using the presented technique has been verified theoretically by means of finite element analysis (FEA) using the commercial code ANSYS. This experimental study is expanded to the study of thermal conductivity of the CPA cocktail DP6--a mixture of 3M DMSO and 3M propylene glycol, which has drawn significant attention in the cryobiology community in recent times. The unique contributions are the first thermal conductivity measurements reported in literature of the combined effect of DP6 with synthetic ice modulators (SIMs), including 6% 1,3Cyclohexanediol, 6% 2,3Butanediol, and 12% PEG400. Results of this study demonstrate that the thermal conductivity may vary by three fold between the amorphous and crystalline phases of DP6 below the glass transition temperature. Results of this study further demonstrate the ability of SIMs to decrease the extent of crystallization in DP6, even at subcritical cooling and rewarming rates. The accompanying theoretical investigation focuses on cryopreservation in a kidney model, in effort to explore how the thermal history is affected by variations in the measured thermal conductivity. This analysis is based on FEA using the commercial code ANSYS. In particular, the unique contributions of this study are: (i) thermal analysis of a vitrifying rabbit kidney based on an established rabbit-kidney cryopreservation protocol, and (ii), exploring scale-up thermal effects to a human-size organ. This represents a 21-fold increase in organ size. Results indicate that even in the case of the human kidney, cooling rates remain high enough in all parts of the kidney to prevent ice formation at temperatures above -100oC.

Background: Heart transplantation remains the gold standard for end-stage heart failure, with current ex vivo organ storage times limited to 4 to 6 h before critical tissue damage occurs. Many preservation solutions exist in an attempt to limit both ischemic and reperfusion damage. In order to compare the effects of various storage solutions, mitochondrial function can be used to provide a sensitive analysis of cellular metabolic function. Methods: Experimental plates were seeded with cardiac myoblasts and kept in suspended animation for either 4 or 8 h at either 4(o) or 21 degrees C, in Celsior (R), Perfadex (R), or Somah storage solutions. Cells were then reanimated for 1 h at 37 degrees C to simulate a reperfusion or clinical transplant scenario. Cellular bioenergetics were measured immediately thereafter to examine biochemical differences between preservation solutions and their effectiveness on preserving metabolic function. Results: The oxygen consumption rates of Somah solution were significantly higher than Celsior (R) and Perfadex (R) at 4 degrees C, with the exception of Perfadex (R) at 4(o) for 4 h. This effect was sustained up to 8 h. At 21 degrees C, oxygen consumption rates of Somah solution are significantly higher than Celsior (R) and Perfadex (R) at basal conditions after 4 h, but this effect is not sustained after 8 h. Conclusions: The purpose of this experiment was to study the efficacy of various preservation solutions on a mitochondrial level. The significantly higher oxygen consumption rates of Somah at 4 degrees C suggests that Somah solution may have the ability to protect cellular mitochondrial integrity, improve transplanted organ function by reducing ischemic-reperfusion injury, and thereby improve transplant outcomes. Given that Somah offers benefits over Celsior (R) and Perfadex (R) at 4 degrees C, it should be a target in future organ preservation solution research.

Cardiac transplantation is the treatment of choice for eligible patients with advanced heart failure; however, it is limited by a critical shortage of suitable organs from traditional brain-dead donors. Organs donated following circulatory death (DCD) have been used to successfully expand the pool of organs available for kidney, liver, and lung transplantation; however, concerns regarding the severity of injury sustained by the heart following withdrawal of life sustaining therapy have deterred the clinical transplantation of DCD hearts. Investigations aiming to optimize the resuscitation, preservation, and evaluation of DCD hearts may facilitate the development of an evidence based protocol for DCD heart transplantation that can be translated to the clinical area and expand the donor pool. Therefore, the objectives of this thesis are to develop a clinically relevant large animal model of DCD and gain a greater understanding regarding the physiologic impact of donor extubation on the DCD heart, demonstrate as a ‘proof-of-concept’ that utilizing an approach to donor heart resuscitation, preservation, and evaluation that is tailored to the DCD context can facilitate successful transplantation, and finally to investigate ways to optimize the resuscitation, preservation, and evaluation of DCD hearts for transplantation. The results of this thesis may then be used to inform the development of an evidence-based protocol for DCD heart transplantation that can be translated to the clinical area. The clinical adoption of such a protocol has the potential to expand the donor pool and improve outcomes for patients with end-stage heart failure. / May 2017

Radiation treatment for head and neck cancer has devastating effects on swallowing ability. Prophylactic swallowing exercises are often recommended. However, the evidence for these exercises is equivocal and information regarding critical components of an exercise program is lacking. The purpose of this systematic review was to examine the evidence regarding lingual strengthening exercises as a component of a prophylactic swallowing program.

Brain death has adverse effects on the organ donor, increasing organ dysfunction and affecting transplantation outcomes. It can also render organs unsuitable for transplantation. Another determinant of organ quality is ischaemia-reperfusion injury, which limits ischaemic storage time for hearts to six hours. The aim of this thesis was to investigate the effectiveness of hormone resuscitation (HR) of the donor to ameliorate the effects of brain death. Another aim was to develop a donor management and organ preservation strategy to ameliorate the effects of ischaemia-reperfusion injury on the heart, thereby extending ischaemic preservation times. A porcine model of the brain-dead multi-organ donor with orthotopic cardiac transplantation was utilised. Donor HR was shown to improve cardiac contractility and haemodynamics, thereby reducing inotrope requirements. A follow-up study investigating the effects of three different donor management protocols demonstrated that donor haemodynamics, renal arterial flow and creatinine clearance were superior in HR animals compared with animals treated with noradrenaline or intravenous fluid alone. Noradrenaline was associated with a significant deterioration in pulmonary function (PaO2 and alveolar-arterial oxygen gradient) and a decline in donor pH. HR was not associated with any detrimental effects on the lungs, liver or pancreas compared with the other two groups. Preservation strategies incorporating glyceryl trinitrate (GTN) and cariporide, a Na+-H+ exchange inhibitor, were investigated to safely extend cardiac ischaemic preservation times. Pre-treatment with intravenous cariporide prior to heart explantation (donor) and reperfusion of the transplanted heart (recipient) was shown to effectively extend ischaemic time to 14 hours, evidenced by weaning off cardiopulmonary bypass. GTN and cariporide-supplemented Celsior, used as a cardioplegic/storage solution, was also effective in extending preservation time to 14 hours, with superior cardiac contractility compared with cariporide pre-treated hearts. Both treatments also ameliorated reperfusion injury, stabilising haemodynamics for up to three hours post-bypass. This thesis has demonstrated the effectiveness of HR to ameliorate the negative effects of donor brain death. It also provides evidence that combined GTN and cariporide-supplemented Celsior improves long-term preservation of the donor heart. These strategies offer the potential to increase the proportion of transplantable organs, to improve donor organ quality, and thereby improve transplantation outcomes.

Orientador: Carlos Takahiro Chone / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-25T13:57:24Z (GMT). No. of bitstreams: 1 Moraes_JulianaLopesde_M.pdf: 943040 bytes, checksum: 4d94adb829d86ae614ad5e737c31b7af (MD5) Previous issue date: 2014 / Resumo: Objetivo: Comparar a qualidade de vida do paciente tratado cirurgicamente por câncer avançado de laringe com aquele que foi submetido a quimioradioterapia exclusivos. Método: Revisão sistemática que utilizou, para a seleção dos artigos, 06 bases de dados (PubMed, MedLine, Embase, Web of Science, Cochrane Library e Lilacs) e as palavras-chave "head and neck cancer"; "advanced laryngeal cancer"; "laryngeal neoplasm"; larynx cancer"; "quality of life"; "outcomes/functional results";"total laringectomy"; "chemoradiotherapy". Os critérios de inclusão foram estudos específicos de câncer avançado de laringe, com comparação de modalidades de tratamento e avaliação da qualidade de vida. Resultados: Foram encontrados 321 artigos. Nove artigos preencheram todos os critérios de inclusão e desses, apenas três possuíam desenho metodológico e instrumento de mensuração de qualidade de vida comparáveis entre si e foram submetidos à metanálise . Os resultados evidenciaram que 90% dos estudos são retrospectivos e não randomizados. O tempo pós-tratamento em que os questionários de qualidade de vida foram aplicados mostrou grande variabilidade (3 meses a 11 anos). Conclusão: A meta-análise dos três estudos comparativos mostraram uma melhor qualidade de vida após o tratamento para indivíduos tratados com quimioradioterapia exlcusiva. No entanto, devido a existência de poucos estudos com dados relevantes na literatura, é necessário realizar pesquisas futuras com as seguintes características: (a) estudos prospectivos e randomizados, (b) multicêntrico, com maior número de indivíduos, e (c) enfatizando o funcional sequelas que ambos os tratamentos acarretam / Abstract: Objective: To compare studies of quality of life in patients undergoing chemoradiotherapy or surgery for advanced laryngeal cancer. Method: Articles were selected for a systematic review by searching six databases (PubMed, Medline, Embase, Web of Science, Cochrane Library and Lilacs) for keywords "head and neck cancer," "advanced laryngeal cancer," "laryngeal neoplasm," "larynx cancer," "quality of life," "outcomes and functional results," "total laryngectomy" and "chemoradiotherapy." The included studies must related to advanced larynx cancer, comparisons of treatment modalities and assessment of patient quality of life in validated scales, well defined inclusion and exclusion criteria. Articles with poor methodological evaluation and duplicated results were excluded. Results: It was found 321 articles. Nine articles fitted to all inclusion criteria and of these, only three observed comparable methodological designs and standardized instruments for measuring quality of life and therefore subjected to meta-analysis. Our analysis observed that 90% of the studies were retrospective and nonrandomized. The time point post-treatment at which the quality of life questionnaires were assessed varied widely (3 months to 11 years). Conclusion: The meta-analysis of three comparable studies showed improved quality of life after treatment for subjects treated with chemoradiation alone. However, because of few studies with relevant data in literature, it is necessary to conduct future research with the following study characteristics: (a) prospective and randomized; (b) multicentric, with larger numbers of subjects; and (c) emphasizing the functional sequelae that both treatments entail / Mestrado / Ciencias Biomedicas / Mestra em Ciências Médicas

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18645号 / 医博第3944号 / 新制||医||1006(附属図書館) / 31559 / 京都大学大学院医学研究科医学専攻 / (主査)教授 伊達 洋至, 教授 羽賀 博典, 教授 千葉 勉 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第21624号 / 医博第4430号 / 新制||医||1033(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 川口 義弥, 教授 福田 和彦, 教授 坂井 義治 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

京都大学 / 新制・論文博士 / 博士(医学) / 乙第13535号 / 論医博第2275号 / 新制||医||1065(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 伊達 洋至, 教授 湊谷 謙司, 教授 小林 恭 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM

INTRODUÇÃO: O transplante traqueal continua um desafio. Contudo, avanços nas técnicas de revascularização dos enxertos traqueais e no conhecimento da imunobiologia da traquéia, indicam que esta técnica pode ser utilizada com freqüência no futuro próximo. A depuração mucociliar (DM) é o mecanismo de defesa inato mais importante das vias aéreas. A traquéia age como um órgão de defesa devido à DM. A DM ocorre por ação do batimento ciliar do epitélio respiratório que impele o muco que atapeta as vias respiratórias, carreando substâncias nocivas. Idealmente, a DM deve ser preservada em enxertos traqueais passíveis de utilização para transplante traqueal. Nosso intuito foi: 1) avaliar os efeitos da isquemia fria sobre a DM; e 2) avaliar a ação de soluções de preservação administradas por via tópica na manutenção da DM após isquemia fria. MÉTODOS: De 109 ratos Wistar foram obtidos 217 segmentos traqueais. Os segmentos foram distribuídos entre três grupos experimentais e um grupo Controle. Cada segmento foi submergido em LPD-glicose (grupo LPD), histidina-triptofano-cetoglutarato (grupo HTK) ou solução salina (grupo Salina). Avaliou-se a DM após 6,10,16 ou 24 horas de isquemia fria. No grupo Controle os segmentos foram analisados imediatamente após a extração, não havendo isquemia fria, nem submersão em soluções. A velocidade de transporte mucociliar (VTM) foi medida através de microscópio de luz, pela observação do movimento das partículas de muco na superfície dos segmentos traqueais. A freqüência de batimento ciliar (FBC) foi obtida pela sincronização entre o movimento ciliar observado pelo microscópio de luz e um estroboscópio. Em seguida, os segmentos foram corados com hematoxilina-eosina para analisar a integridade epitelial (IE) e a inflamação subepitelial (IS). Foi realizada análise quantitativa do muco intracelular por um programa de computador após coloração com azul de alcião (MI-AA) e PAS (MI-PAS). As amostras mais significativas foram analisadas qualitativamente por microscopia eletrônica de transmissão (ME). Foram realizadas duas análises: 1) grupo Controle e tempos de isquemia; e 2) grupo Controle e soluções de preservação (agrupado pelo tempo de isquemia). RESULTADOS: 1) grupo Controle e tempos de isquemia: O grupo controle foi melhor que os grupos submetidos a isquemia fria quanto à VTM (p=0,0001) e FBC (p=0,012). Contudo, não houve diferença na IE, IS e MI entre o grupo Controle e os demais grupos. 2) grupo Controle e soluções de preservação: O grupo controle apresentou melhor VTM que os grupos LPD, HTK e Salina após isquemia de 6h (p=0,001), 16h (p=0,009) e 24h (p=0,001). O grupo controle apresentou melhor FBC que os grupos LPD, HTK e Salina após isquemia de 24h (p=0,001). Não houve diferença entre os grupos na IE e IS. O grupo Controle apresentou melhor MI-AA que os grupos LPD após 16h (p=0,02) e HTK após 24h de isquemia (p=0,04). Não houve diferença entre os grupos à MI-PAS. À ME, o grupo Salina apresentou maiores alterações secundárias à isquemia do que os demais grupos. CONCLUSÕES: 1) A isquemia fria piora a DM; e 2) O uso de soluções de preservação administradas por via tópica não contribui para manutenção da DM após isquemia fria / INTRODUCTION: Tracheal transplantation is a challenging problem. Recent advances in graft revascularization, and reepithelialization renewed the interest on airway transplantation. Mucociliary clearance (MC) is the most important innate defense mechanism of the respiratory system. MC works by mucous transport carried out by ciliary beating function of the airway epithelium. Trachea acts as a defense organ in the respiratory system through the MC. Ideally, MC should be preserved in tracheal grafts used for transplantation. Preservation solutions improve organ preservation by decreasing ischemic injury. The purpose of the study was: 1) to evaluate the effects of cold ischemia on MC; and 2) to evaluate the impact of topically-applied preservation solutions on MC after cold ischemia. METHODS: From 109 male Wistar rats we obtained 217 tracheal segments. The segments were allocated to one of four groups. Segments were submerged in LPD-glucose (LPD group), histidine-tryptophan-ketoglutarate (HTK group), or saline solution (Saline group), and stored at 4C. MC was analyzed after 6, 10, 16 or 24h of ischemia. Control group have only segments that were analyzed right after extraction, not submitted to cold ischemia or submersion in preservation solutions. The mucociliary transport velocity (MTV) was measured by observation of mucous particle under the surface of the segments, through a light microscope. Ciliary beating frequency (CBF) was achieved by synchronization between cilia movement and a stroboscope flashlight. Tracheas were stained with hematoxylin-eosin in order to analyze the epithelial integrity (EI) and the subepithelial inflammation (SI). A quantitative analysis of the intracellular mucus stained with alcian blue (IM -AB) and PAS (IM-PAS) was achieved by a software. The most significant samples of the tracheal segments were qualitatively analyzed by transmission electronic microscopy (TEM). Two analyses were made: 1) Control group and ischemic time; and 2) Control group and preservation solutions. RESULTS: 1) Control group and ischemic time: Control group had better VTM (p=0,0001) and CBF (p=0,012) than the groups submitted to cold ischemia. However, there was no difference among Control group and the other groups on EI, SI, IM-AB, and IM-PAS. 2) Control group and preservation solutions: Control group showed better MTV than the LPD, HTK, and Saline groups after 6h (p=0,001), 16h (p=0,009) and 24h (p=0,001) of cold ischemia. Control group showed better CBF than the LPD, HTK, and Saline groups after 24h of ischemia (p=0,001). There was no difference among groups on EI and SI. Control group showed better IM-AB than both the LPD group after 16h of cold ischemia (p=0,02), and the HTK group after 24h of cold ischemia (p=0,04). There was no difference among the groups on IM-PAS. TEM showed more findings of ischemic lesion on Saline group. CONCLUSIONS: 1) Cold ischemia impairs MC; and 2) Topically-applied preservation solutions do not ameliorate MC after cold ischemia