• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 47
  • 46
  • 15
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 144
  • 42
  • 24
  • 19
  • 18
  • 12
  • 10
  • 10
  • 10
  • 9
  • 9
  • 9
  • 9
  • 9
  • 9
  • 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.
51

Verificação da potencialização do efeito cicatrizante do muco de caracóis do gênero Achatina promovida por dieta à base de Confrei (Symphytum officinale) / Investigation on the scar potential effect of mucus in the land snail Achatina fed with a diet based on Comfrey (Symphytum officinale)

Sirio, Otavio José 20 December 2005 (has links)
Os caracóis terrestres são animais capazes de produzir através de glândulas localizadas em toda superfície do seu corpo, uma secreção glicoproteica denominada muco, que dentre outras funções, apresenta poder antibacteriano, que pode auxiliar nos processos de reparação de feridas de origens diversas. Desta forma, o objetivo da presente pesquisa foi o de avaliar macroscópica e histologicamente, os efeitos reparadores do muco dos escargots Achatina fulica e Achatina achatina monochromatica, em lesões provocadas na pele de camundongos da linhagem "hairless"; verificar sua potencialização após a ingestão de uma ração contendo em sua formulação uma planta com propriedades cicatrizantes comprovadas, o Confrei (Symphytum officinale); e analisar bioquimicamente a composição do muco destes caracóis. Foram selecionados caracóis das espécies Achatina fulica (n=30) e Achatina monochromatica monochromatica (n=30), retirado seu muco através de estimulação manual da glândula podal e verificação de seu efeito reparador. Utilizaram-se camundongos da linhagem "hairless" (n=75), submetidos à intervenção cirúrgica e tratados com muco de ambas as espécies de caracóis. As características macroscópicas da lesão foram registradas em protocolo e avaliadas. Fragmentos de pele foram submetidos à biópsia aos 3, 5 e 7 dias de experimento, fixados em Paraformoldeído, processados e incluídos em parafina. Os cortes foram corados com Hematoxilina-Eosina e Tricrômio de Mason. Macroscopicamente, os animais tratados mostraram edemas menores, maior presença de crosta e maior contração das bordas das feridas ao final do experimento, quando comparados ao grupo controle. Histologicamente, os grupos tratados também revelaram melhor reparação da lesão, apresentando edemas menos intensos, grandes quantidades de tecido de granulação e infiltrados inflamatórios. O grupo tratado com muco de caracóis alimentados com ração contendo Symphytum officinale foi o que apresentou melhores resultados. / Land snails are animals able to produce through glands located all over their body surface, a glycoprotein secretion called mucus. This mucus, within other roles, shows an antibacterial power that can help in the healing processes of wounds from several sources. Therefore, the aim of this study was to evaluate through macroscopic and histological techniques the repairing effects of the mucus in the snails Achatina fulica and Achatina achatina monochromatica in lesions intentionally caused to hairless linage mice skin; to investigate mucus potential effect after snails have been fed with a diet formulation containing a plant with proved scar properties, the Comfrey (Symphytum officinale); and to study the biochemical composition of mucus from these snails. Snails of Achatina fulica (n=30) and Achatina monochromatica monochromatica (n=30) species were sorted, the mucus extracted through manual stimulation of the podal gland and the repairing effect studied. Hairless linage mice (n=75) used in this study went through surgery and then treated with mucus from both species of snails. The macroscopic characteristics of the lesion were recorded and assessed. Fragments of skin were taken to biopsy at 3, 5 and 7 days of trial, fixed in paraformaldehyde, processed and embedded in wax. Sections were stained with Hematoxilin-Eosin and Tricromio of Mason. Macroscopically, treated mice showed minor swelling, higher presence of scabs and higher contraction of wound edges at the end of the trial, when compared with control. Histologically, groups that received treatment also showed better lesion repair, presenting less intense swellings, large amount of scar tissue and inflammatory infiltrates. The group treated with mucus from snails that received a diet containing Symphytum officinale presented the best results.
52

Polymeric airway mucins in equine recurrent airway obstruction

Williams, Adele January 2014 (has links)
In healthy airways, mucus forms part of the innate immune response protecting the respiratory epithelium from damage by pathogens and environmental debris (Rose and Voynow, 2006). Conversely, in many respiratory diseases, mucus becomes part of the airway disease pathology. Mucus hypersecretion along with reduced clearance can cause blockage of the small airways, impairing gas exchange, promoting inflammation and becoming a culture medium for bacterial colonisation (Thornton et al., 2008). Recurrent airway obstruction (RAO) is a common yet poorly understood equine chronic respiratory disease where such altered mucus properties and clearance have been identified as major factors in the disease pathology (Davis and Rush, 2002; Gerber et al., 2000; Kaup et al., 1990; Robinson, 2001). The gel-forming mucins are largely responsible for the transport properties of mucus. The major equine airway gel-forming mucin in health is Muc5b and to a lesser extent Muc5ac; produced in specialised respiratory epithelial goblet cells and sub-mucosal glands (Rousseau et al., 2011b). Changes in mucin relative and net amounts and their macromolecular properties and interactions have been attributed to the altered physical properties of airway mucus in airways disease (Groneberg et al., 2002a; Jefcoat et al., 2001; Kirkham et al., 2002; Robinson et al., 2003; Sheehan et al., 1995).The project investigates the biochemical properties of mucins present in mucus from healthy horses and horses with RAO. This project identifies the anatomical presence of mucin-producing goblet cells and glands in fixed tissues from the respiratory tracts of healthy horses and subsequently examines mucin-production sites in respiratory tracts from horses with RAO. Finally the project investigates a methodology for the study of mucin production in airway cells harvested from live horses suffering from RAO.Our investigations confirmed that horses with RAO have more endotracheal mucus than healthy controls, and that Muc5b is the predominant mucin with Muc5ac also present in RAO horse mucus, both during symptomatic disease and when horses are asymptomatic. Mucins are produced in epithelial goblet cells and sub-mucosal glands dispersed throughout the length and circumference of the equine trachea and bronchi. Goblet cell hyperplasia occurs in symptomatic exposed RAO horse airways, although goblet cells are smaller than in asymptomatic RAO horse airways. Exposure to a dusty stable environment is associated with more goblet cells per length of bronchial compared to tracheal epithelium in all horses. RAO horses have larger sub-mucosal glands containing more mucin than control horses. Primary epithelial cell cultures grown at an air liquid interface are an alternative approach to study equine airway mucus, although the use of this culture system is in its early stages. We have developed novel ways to harvest equine airway epithelial cells (tracheal brushing) and shown it is possible to freeze cells collected via tracheal epithelial brushing in 20 % FBS and then culture to ALI at a later date.
53

Resposta imune induzida pelas peçonhas do bagre Cathorops agassizii

Junqueira, Marcos Emerson Pinheiro [UNESP] 20 April 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-04-20Bitstream added on 2014-06-13T18:41:14Z : No. of bitstreams: 1 junqueira_mep_dr_botfm.pdf: 683998 bytes, checksum: e97592029abff7e2b2e4961aed2d337c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Gap / Nossos estudos objetivaram caracterizar as respostas imune inata e específica induzidas pelas peçonhas do muco e do ferrão do bagre Cathorops agassizii . A coleta dos espécimes foi realizada no complexo Baía-Estuário de Santos e São Vicente, localizado no litoral sul do Estado de São Paulo. As peçonhas (do Muco e do Ferrão) apresentaram perfil eletroforético similar entre si. Induzida a inflamação aguda em um modelo experimental murino, as peçonhas apresentaram igualmente a capacidade de induzir aumento da permeabilidade vascular e também edema de pata. A detecção de Leucotrieno B4 e Prostaglandina E2 no lavado da cavidade peritoneal dos camundongos injetados, com ambas as peçonhas, corroboram esta hipótese. Nossos resultados através da microscopia intravital mostraram que as peçonhas induzem um grande número de leucócitos rolantes nas vênulas pós-capilares com focos de extravasamento leucocitário, principalmente de neutrófilos seguido pelo influxo de macrófagos. Além disso, a peçonha do Ferrão induziu uma resolução mais rápida do influxo leucocitário ao contrário da peçonha do Muco que manteve o infiltrado macrofágico por até 7 dias. De maneira interessante, somente a citocina IL-6 foi detectada no lavado peritoneal induzida principalmente pela peçonha do Muco e as quimiocinas KC e MCP-1, por ambas as peçonhas, expressando naquele momento, a participação destes mediadores no recrutamento de neutrófilos e macrófagos para o sítio da lesão. As peçonhas foram eficazes ao induzir uma produção primária e secundária de anticorpos das classes IgM e IgG anti-venenos. Observamos ainda, uma especificidade dos anticorpos produzidos para os componentes das próprias peçonhas e também uma reatividade antigênica cruzada entre elas. / Our studies aimed to characterize the innate and specific immune responses induced by poisons of the mucus and sting of the catfish Cathorops agassizii. The collection of specimens was accomplished in the complex Bay-Estuary System of Santos and São Vicente located in the south coast of the São Paulo State. Poisons of the Mucus and Sting presented similarities in their electrophorectical profiles. In basis of an Induced process of inflammation throughout an experimental murine model, both poisons equally showed the capacity to increase the vascular permeability and also paw edema. The Leucotrien B4'S and Prostaglandine E2 detection in washings of mice peritoneal cavity injected with both poisons corroborates this hypothesis. Our results through an intravital microscopy procedure also showed that the poisons induced a great number of rolling leukocytes in the post-capillary venules with focus on the leukocyte overflow mainly neutrophiles followed by macrophage influx. Besides, the sting poison Sting induced a faster resolution of the leukocyte influx, as well as, the Mucus poison unlike maintained a macrophage infiltrated for up to 7 days. In an interesting way, only the cytokine IL-6 was detected in peritoneal washings induced mainly by the Mucus poison although Quimiokinins KC and MCP-1 were for both poisons, expressing on that moment the participation of these mediators in the neutrophile and macrophage recruitment for the lesion site. The poisons were also effective in the induction of a primary and secondary production of IgM and IgG classes of antibodies. In this research we still observed a specificity of the antibodies produced for the components of the own poisons and also a crossed antigenic reactivity among them.
54

Efeitos do envelhecimento, isolado e associado ao diabetes e/ou à hipertensão sobre o transporte mucociliar e propriedades físicas do muco nasal / The effects of aging, isolated and associated with diabetes and/or hypertension on nasal mucociliary clearance and mucus properties

Oliveira, Janaína Proença de 15 December 2011 (has links)
A pneumonia é uma das principais causas de morte na população idosa. O prejuízo do transporte mucociliar pode aumentar a susceptibilidade à infecção respiratória. Nosso objetivo foi avaliar os efeitos do envelhecimento, isolado e combinado com diabetes ou hipertensão, sobre a transporte mucociliar nasal e as propriedades do muco. De 440 pacientes contactados por telefone, 252 pessoas participaram do estudo: 79 saudáveis (18-94 anos, 50 homens), 38 indivíduos com diabetes (14-85 anos, 13 homens), 51 indivíduos com hipertensão (23-90 anos, 12 homens) e 84 indivíduos com diabetes e hipertensão (18-84 anos, 33 homens). Os indivíduos foram divididos em dois grupos principais, saudável e co-morbidade. Cada grupo foi separado em três sub-grupos de faixas etárias: (a) <40 anos, (b) 40-59 anos e (c) 60 anos. Foram avaliados os dados demográficos, os dados clínicos, o questionário de Qualidade de Vida SF-36, o pH nasal, o transporte mucociliar nasal por meio do teste de tempo de trânsito da sacarina (TTS), as propriedades do muco in vitro por meio da transportabilidade do muco por alto fluxo e o ângulo de contato. Neste estudo, observamos no grupo saudável uma maior frequência de mulheres (p=0,040) no sub-grupo 60 anos (70%) comparado com <40 anos (35%) e 40-59 anos (22%). Nos indivíduos saudáveis não observamos diferença entre as faixas etárias quanto aos seguintes parâmetros: sumário do componente físico do SF-36 (51±7), sumário do componente mental do SF-36 (51±9), pressão arterial sistólica (116±7 mmHg), pressão arterial diastólica (76±6 mmHg), freqüência cardíaca (74±10 bpm), frequência respiratória (17±3 rpm), oximetria de pulso (97±1%), glicemia (98±8 mg/dl), pH nasal (6,7±1,3), TTS (9,5±2,7 min), transportabilidade do muco por alto fluxo (46±18 mm) e ângulo de contato do muco (42±7°). No entanto, no grupo co-morbidade, o subgrupo 60 anos apresentou aumento do índice de massa corpórea (p=0,021), da pressão arterial sistólica (p<0,001), da frequência respiratória (p<0,001) e do TTS (p=0,003) e redução do sumário do componente físico SF-36 (p<0,001) em comparação com o sub-grupo <40 anos. Observamos correlação entre TTS e idade associada a co-morbidades (p<0,001). Nosso estudo sugere que o envelhecimento combinado com o diabetes e/ou a hipertensão podem reduzir a eficiência do transporte mucociliar nasal / Pneumonia is a leading cause of death in elderly populations. Impairment of mucociliary clearance may increase susceptibility to respiratory infection. We aimed to evaluate the effects of aging alone and in combination with diabetes or hypertension on nasal mucociliary clearance and mucus properties. Of 440 subjects contacted by telephone, 252 entered the study: 79 healthy subjects (18-94 yrs, 50 male); 38 with diabetes (14-85 yrs, 13 male); 51 with hypertension (23-90 yrs, 12 male); and 84 with both diabetes and hypertension (18-84 yrs, 33 male). The subjects were divided into healthy and co-morbid groups. Each group was separated into three subgroups by age: (a) <40 yrs, (b) 40-59 yrs, and (c) 60 yrs. We assessed demographic data, clinical data, quality of life questionnaire (SF-36), nasal pH, nasal mucociliary clearance using the saccharine transit test (STT) and in vitro mucus properties by examining the high-flow clearability and contact angle. In this study, in the healthy group there was a high frequency of female (p=0.040) in the sub-group 60 yrs (70%) compared with <40 yrs (35%) and 40-59 yrs (22%). In healthy group, there were no differences between age groups in SF-36 physical component summary (51±7), SF-36 mental component summary (51±9), systolic blood pressure (116±7 mmHg), diastolic blood pressure (78±6 mmHg), heart rate (74±10 bpm), respiratory rate (17±3), pulse oximetry (97±1%), glycemia (98±8 mg/dl), nasal pH (6.7±1.3), STT (9.5±2.7 min), high-flow clearability (46±18 mm), and mucus contact angle (42±7o). In the co-morbid group, however, subjects aged 60 yrs had higher body mass indices (p=0.021), systolic blood pressures (p<0.001), respiratory rate (p<0.001), STT (p=0.003) and decreased SF-36 physical component summary scores (p<0.001) compared to the subjects aged <40 yrs. There was a significant correlation between STT and aging associated with co-morbid conditions (p<0.001). Our study suggests that aging combined with diabetes and/or hypertension can reduce nasal mucociliary clearance efficiency
55

Avaliação e caracterização proteica do muco de Phyllocaulis boraceiensis sobre a capacidade proliferativa de fibroblastos, células endoteliais e em modelos de cicatrização. / Evaluation and protein characterization of Phyllocaulis boraceiensis mucus in proliferative capability in fibroblasts, endothelial cells and cicatrization model.

Piza, Ana Rita de Toledo 03 August 2012 (has links)
Gastrópodes terrestres secretam muco pela superfície corporal, quando se locomovem, para proteção do corpo contra injúria mecânica, dessecação ou contato com substâncias nocivas. O muco de moluscos tem sido estudado como fonte de novos compostos naturais com diversas atividades biológicas, entre elas a capacidade de induzir proliferação celular. O presente trabalho propôs o estudo do muco produzido pelas lesmas terrestres Phyllocaulis boraceiensis como agente indutor de proliferação celular e síntese de colágeno em cultura de fibroblastos humanos normais, células endoteliais e no reparo de processos cicatriciais no modelo de ferida cirúrgica da derme de camundongos. Fibroblastos tratados com proteínas do muco de P. boraceiensis em concentrações menores que 0,012 <font face=\"Symbol\">mg/µl apresentaram aumento nas taxas de proliferação avaliadas pelo método colorimétrico do MTT e em citometria de fluxo CSFE, mostrando um efeito dose-dependente. Os resultados obtidos mostraram que fibroblastos humanos normais e células endoteliais tratados com 0,012 g/<font face=\"Symbol\">ml de proteínas do muco, aumentaram significativamente a produção e secreção de elementos da matriz extracelular, como as fibras de colágeno. Houve a redução da produção de radicais livres lipídicos poli-insaturados. O ensaio de cicatrização da derme lesionada de camundongos Balb-c tratados com proteínas do muco de P. boraceiensis na concentração de 0,012 <font face=\"Symbol\">mg/µl induziu o reparo da cicatrização com maior eficácia e em menor tempo quando comparado ao grupo controle e aos tratados com a concentração de 0,18 <font face=\"Symbol\">mg/µl. Esses resultados corroboram a premissa de que o muco de P. boraceiensis, assim como o de outros gastrópodes, apresenta propriedade proliferativa das células envolvidas nos processos de cicatrização. / Mucus of molluscs has been studied as a source of new natural compounds with diverse biological activities, as ability to induce cell proliferation. The aim of this study is the potential use of mucus produced by land slugs Phyllocaulis boraceiensis as a promoter of cell proliferation and collagen synthesis in human fibroblasts, endothelial cells and in repair processes of healing wound skin of mice. Fibroblasts treated with P. boraceiensis mucus at concentrations below 0.012 <font face=\"Symbol\">mg/µl have high rates of proliferation as evaluated by the MTT and CFSE flow cytometer assays, proliferative effect was dose-dependent. Fibroblasts and endothelial cells treated with 0.012 <font face=\"Symbol\">mlowg/µl mucus induced a significant increase in production and secretion of extracellular matrix such as collagen fibers. There was a reduction in polyunsaturated lipid production. Healing assay of lesions in mice treated with mucus at 0.012 <font face=\"Symbol\">mg/µl induce repair of the scar more effectively and in less time when compared to the control group and those treated 0.18 <font face=\"Symbol\">mg/µl. These findings support the premise that the P. boraceiensis mucus demonstrates proliferative properties in cells involved in the healing process.
56

Avaliação de clearance nasal, propriedades físicas do muco, celularidade e citocinas em lavado nasal de trabalhadores cortadores de cana-de-açúcar queimada no Estado de São Paulo / Evaluation of nasal mucociliary clearance, mucus physical properties, cellularity and cytokines in nasal lavage of sugarcane workers in São Paulo State

Goto, Danielle Miyuki 09 March 2012 (has links)
A queima de biomassa produz gases tóxicos e partículas suspensas que contribuem para a poluição atmosférica. Este estudo avaliou os efeitos da colheita de cana-de-açúcar queimada sobre o transporte mucociliar (TMC) nasal, as propriedades físicas do muco nasal e celularidade e concentrações de citocinas em lavado nasal (LN) de cortadores de cana-de-açúcar e residentes de região urbana próxima aos canaviais (Mendonça, São Paulo). Métodos: Avaliamos 154 jovens não tabagistas (idade entre 18 e 43 anos) sendo 73 residentes e 81 cortadores na: (a) Pré-safra: 4 meses sem exposição à queimada de biomassa (fevereiro e março), e na (b) Pós-safra: aproximadamente 7 a 8 meses de exposição (outubro e novembro). Avaliamos: o TMC nasal por meio do teste da sacarina (TTS), as propriedades físicas do muco por meio da transportabilidade por alto fluxo e ângulo de contato, a expressão de fator de necrose tumoral (TNF)-, interleucinas (IL)-4, IL-6, IL-8 e IL-10 em LN, celularidade total e diferencial em LNsinais vitais e ocorrência de eventos respiratórios. Resultados: Na Pré-safra, comparados com os residentes, cortadores apresentaram menor pressão arterial média (95,5±9,1 e 88,7±9,4 mmHg, respectivamente; p<0,001), frequência cardíaca (76±13 e 70±10 bpm, respectivamente; p<0,003), e células ciliadas (61±20 e 47±18%, respectivamente; p<0,001). Além de TTS mais prolongado (10,4±4,6 e 11,8±5,1, respectivamente; p=0,035), e maior porcentagem de macrófagos em LN (21±15 e 43±15%, respectivamente; p<0,001). Na Pós-safra, comparados com os residentes, os cortadores apresentaram menor pressão arterial média (96,5±9,1 e 92,8±9,6 mmHg, respectivamente; p=0,042), frequência cardíaca (76±14 e 63±11 bpm, respectivamente; p<0,001), IL-4 (0,4±0,5 e 0,3±0,6 pg/ml, respectivamente; p=0,001), células ciliadas (64±19 e 52±14%, respectivamente; p<0,001), células caliciformes em LN (13±14 e 4±5%, respectivamente; p<0,001), assim como maior número de células totais (24±29 e 32±30 104células/ml, respectivamente; p=0,040), neutrófilos (1±2 e 2±3%, respectivamente; p<0,001), eosinófilos (0±0 e 0±1%, respectivamente; p<0,001), macrófagos (21±16 e 40±13%, respectivamente; p<0,001) e IL-6 (2,8±3,4 e 4,0±3,7 pg/ml, respectivamente; p=0,026) em LN. Não houve diferenças significantes nas propriedades físicas do muco, na quantificação da secreção de IL-8 e TNF-, e na porcentagem de linfócitos em LN entre os dois grupos e ao longo do estudo. Conclusão: A queimada de cana-de-açúcar induz alterações na primeira barreira de defesa do sistema respiratório em residentes e em cortadores da área urbana próxima aos canaviais observada por aumento no CO exalado, aumento de celularidade total e redução da concentração de IL-10 em LN em residentes, e prolongamento do TTS acompanhado de aumento na expressão de IL-6 e células ciliadas em LN em cortadores / Biomass burning produces toxic gases and suspended particle that contribute for high levels of air pollution. We aimed to assess the effects of sugarcane harvesting on nasal mucociliary clearance (MCC), mucus physical properties, and celularity and cytokines concentrations in nasal lavage (NL) of sugarcane workers and residents that live near to sugarcane fields (Mendonça, São Paulo). Methods: We evaluated 154 young non-smoking subjects, aged between 18 to 42 years (residents, n=73 and sugarcane workers, n=81) at two time-points: (a) non-harvesting, 4-months of no exposure to biomass burning (in February and March), and (b) harvesting, after 7 to 8-months of exposure to biomass burning (in October and November). We evaluated: Nasal MCC was assessed by saccharine transit test (STT), mucus physical properties were evaluated by sneeze clearability and contact angle, expression of tumor necrosis factor-, interleukin (IL)-4, IL-6, IL-8 e IL-10 in NL and total and differential cells counts in NL, vital signs and respiratory events. Results: At Non-harvesting, compared with residents, sugarcane workers presented lower mean blood pressure (95.5±9.1 and 88.7±9.4 mmHg, respectively; p<0.001), heart rate (76±13 and 70±10 bpm, respectively; p<0.003), and ciliated cells (61±20 and 47±18%, respectively; p<0.001) and prolonged STT (10.4±4.6 and 11.8±5.1, respectively, p=0.035), and higher percentage of macrophages in NL (21±15 and 43±15%, respectively; p<0.001). At Harvesting, compared with residents, sugarcane workers presented lower mean blood pressure (96.5±9.1 and 92.8±9.6 mmHg, respectively; p=0.042), heart rate (76±14 and 63±11 bpm, respectively; p<0.001), IL-4 (0.4±0.5 and 0.3±0.6 pg/ml, respectively, p=0.001), ciliated cells (64±19 and 52±14%, respectively; p<0.001), goblet cells (13±14 and 4±5%, respectively; p<0.001), and higher number of total cells (24±29 and 32±30 104cells/ml, respectively; p=0.040), neutrophils (1±2 and 2±3%, respectively, p<0.001), eosinophils (0±0 and 0±1%, respectively, p<0.001), macrophages (21±16 and 40±13%, respectively, p<0.001) and IL-6 concentration in NL (2.8±3.4 and 4.0±3.7 pg/ml, respectively, p=0.026). There were no significant differences in mucus physical properties, concentration of IL-8 and TNF-, and percentage of lymphocytes in NL between the two groups and along the study. Conclusion: Sugarcane burning induces changes in the first defense barrier of the respiratory system in residents of the urban area near of the sugarcane fields and in sugarcane workers which were observed by increase in exhaled CO and total cell count, and a decrease in IL-10 concentrations in NL in residents, and prolonged STT accompanied by an increase in IL-6 concentration and percentage of ciliated cells in NL in sugarcane workers
57

Development of a physiologically-relevant in vitro system to study exhaled bioaerosols

Hamed, Rania Ahmad Azzam 01 July 2011 (has links)
Airborne infectious diseases remain a major global health threat. The primary vector for their transmission is coarse and fine droplets, known as bioaerosols, exhaled from infected individuals during natural respiratory maneuvers, such as breathing, coughing and sneezing. Unfortunately, our current knowledge of the mechanisms by which these exhaled bioaerosols are formed in the lungs is in its infancy. In particular, progress in this field has been hindered by the complex structure of the respiratory fluid and the resulting lack of understanding of the biophysical properties of the fluid. In this thesis, a series of in vitro mimetics of conducting airway mucus were developed to enable in depth studies of mucus properties and bioaerosol formation from mucus-like surfaces. These mucus mimetics overcome major limitations of currently available models by matching the primary chemical composition and key physical properties of the mimetic to that of native tracheal mucus. Three mimetics were chosen to facilitate the study of highly viscoelastic (diseased) mucus and non-diseased mucus under low shear conditions, such as breathing, or high shear conditions, such as cough. To study bioaerosol formation in vitro, an enhanced simulated cough machine (SCM) was developed to generate bioaerosols from mucus mimetic surfaces during cough. By controlling the temperature and relative humidity within the SCM, the detectability of bioaerosols generated from the mimetic surfaces was improved due to limited aerosol drying. The size distribution of the bioaerosols was multimodal, with four to five modes being observed for all surfaces probed. While varying the composition of surfactant at the air-mucus interface had a significant impact on surface viscoelastic properties, the size distribution of bioaerosols generated from these surfaces did not differ significantly. However, the ability to generate bioaerosols from different surfaces was highly dependent on surface properties of the mimetic, with highly viscoelastic surfaces generating bioaerosols in only half the experiments. This research will enhance our knowledge of bioaerosol formation in the respiratory tract and ultimately guide the development of alternative strategies to suppress bioaerosol formation.
58

Magnetically targeted deposition and retention of particles in the airways for drug delivery

Ally, Javed Maqsud 06 1900 (has links)
This thesis examines the mechanisms of magnetic particle deposition and retention in human airways for magnetically targeted drug delivery. As this is a novel application, fundamental studies were performed to establish the necessary background knowledge for further development. Magnetic particle deposition from an aerosol in simulated airway conditions was studied using numerical and experimental models. The model results showed qualitative agreement; discrepancies were due to particle aggregation, which enhances deposition. Aerosol flow rate had a limited effect; the main factor in effective deposition was the proximity of the particle trajectories to the magnets. This spatial bias shows the importance of particle distribution in the flow as well as magnetic field geometry. These studies demonstrated the feasibility of capturing magnet particles from aerosol in airway conditions. For retention, clearance of particles due to motion of the mucus lining of the airways must be overcome. Particle retention was studied in vitro using various liquids to simulate mucus and identify relevant parameters. An ex vivo animal tissue model was used to demonstrate feasibility. Retention of 3-5 m diameter iron particles was achieved at reduced liquid/mucus viscosities. Larger (~100 m) particles were retained at normal mucus viscosities. The size dependence shows that particle aggregation after deposition is crucial for effective retention. In vitro retention experiments showed aggregate size is correlated with liquid viscosity, i.e. formation of aggregates is limited by forces opposing particle motion along the mucus layer interface. To determine these forces, particle motion on various air-liquid interfaces, chosen to simulate different mucus properties in isolation, was studied. When surfactants are present, as in the mucus layer, particle motion is limited by a velocity-dependent surface tension gradient as well as viscous drag. Pulling particles through the mucus layer into the tissue beneath was also considered as a potential retention strategy. The force required to pull particles through the mucus layer was also studied using various liquids to simulate mucus properties. In addition to the surface tension force holding the particles at the interface, hydrodynamic forces must be overcome to pull particles into or out of a liquid film such as the mucus layer.
59

Comparative Study of HPV 16 and HPV 18 Antibody Detection in Serum, Cervical Mucus, and Oral Mucosal Transudate

Blalock, Emily Lauren 22 November 2008 (has links)
Measuring HPV exposure relies on detection of HPV type-specific antibodies, but methods are not standardized. Additionally, there is little information on the best sample type for HPV antibody detection. This study validated pseudovirion neutralization (PVN) assay for HPV antibody detection and compared it to IgG ELISA. Both assays were applied to paired serum and cervical mucus samples. Additionally, PVN assay was utilized to evaluate the feasibility of oral mucosal transudate (OMT) samples to monitor the HPV immune response. Serum was more likely to be positive on PVN assay than on IgG ELISA (p= 0.025). Both assays correlated with HPV-16 DNA status. HPV-18 PVN assay results correlated with HPV-18 DNA status. Few cervical mucus samples had detectable antibodies; no correlation with HPV DNA status was seen. OMT results were unsatisfactory. PVN assay was more sensitive than IgG ELISA; serum was a more reliable indicator of HPV-16/18 antibody status than cervical mucus.
60

Mechanisms of Rupture of Mucin Vesicles from the Slime of Pacific Hagfish (Eptatretus stoutii): Roles of Inorganic Ions and Aquaporin Water Channels

Herr, Julia Emily 28 May 2012 (has links)
Pacific hagfish (Eptatretus stoutii) slime mucin vesicles are released by holocrine secretion with membranes that remain intact until the vesicle contacts seawater and ruptures. This thesis is an investigation of the mechanisms that drive mucin vesicle rupture for mucin release. Using isolated mucin vesicles collected from the slime glands of the hagfish, I tested the effects of a variety of solutions and drugs on vesicle rupture. I found that there are two categories of mucin vesicle that differ in their sensitivity to calcium ions, and that calcium-dependent vesicle rupture was inhibited with anion channel inhibitors. I also found that vesicle swelling rate was reduced by the aquaporin inhibitor mercuric chloride. Together, these data suggest that mucin vesicle rupture is partially dependent on the movement of chloride ions from seawater through calcium-activated anion channels and the rapid influx of water through aquaporin-like proteins in the vesicle membrane. / NSERC Discovery Grant, NSERC CGSM scholarship, Canada Foundation for Innovation, Ontario Ministry of Research and Innovation

Page generated in 0.0409 seconds