Introdução: Em pacientes sob intubação endotraqueal os mecanismos fisiológicos de climatização do ar inspirado são anulados. Durante anestesia geral, quando os gases inspiratórios são ofertados secos e frios, a manutenção da umidade das vias aéreas é condição importante para prevenção de lesões da mucosa respiratória e ressecamento das secreções. Os sistemas de anestesia possuem propriedades de umidicação inerentes, decorrentes do sistema respiratório circular e a presença do absorvedor de CO2. Entretanto, os níveis de umidificação, durante a anestesia, dependem de vários fatores incluindo o tipo de ventilador anestésico, montagem do sistema respiratório e o fluxo de gás fresco utilizado. Porém não há dados na literatura que tenham investigado o efeito nos níveis de umidade do gás inspirado nas propriedades físicas e de transportabilidade do muco respiratório. Objetivo: Avaliar os níveis de Temperatura (T), umidade absoluta (UA) e umidade relativa (UR) do ar inspirado durante anestesia geral oferecidos pelo sistema circular valvular com absorção de CO2 e com a adição do HME em dois tipos de ventiladores (Dräger e Takaoka). Avaliar os efeitos do HME sobre os níveis de Temperatura e Umidade dos gases inspirados ofertados pelos dois equipamentos. Avaliar o impacto da umidade sobre as propriedades físicas e de transportabilidade do muco respiratório. Método: Foram selecionados 44 pacientes da Clínica Cirúrgica II do Departamento de Gastroenterologia do HCFMUSP com indicação de cirurgia abdominal eletiva e anestesia geral com duração superior a 4 horas. Os pacientes foram alocados em 4 grupos conforme o tipo do ventilador utilizado (Dräger ou Takaoka) e a presença ou ausência do HME. O muco respiratório e os dados de temperatura, UR e UA do gás ofertado foram coletados logo após a intubação endotraqueal, e a cada duas horas até o final da cirurgia. A análise do muco respiratório foi realizada através dos seguintes métodos: Transportabilidade mucociliar (MCT), em palato de rã; Transportabilidade pela tosse (TT), através da máquina simuladora da tosse e as propriedades de superfície, através do Ângulo de contato (AC). Resultado: O ventilador Dräger foi significantemente mais efetivo em ofertar níveis mais altos de T, UA e UR comparado ao ventilador Takaoka. A adição do HME aumentou a T e UA nos dois equipamentos. A UR aumentou somente no ventilador Takaoka. Houve um aumento do TMC e da TT no grupo que apresentou níveis mais altos de umidade (i.e. Dräger + HME). O AC não mostrou diferenças entre os quatro grupos. A análise longitudinal mostrou que o TMC foi positivamente afetado com o aumento da UA e UR. A TT foi positivamente afetada com a adição do HME. Conclusão: Nossos resultados mostram que o ventilador Dräger produziu níveis significantemente mais altos de umidade comparados ao ventilador Takaoka e que a adição do HME aumentou os níveis de umidade nos dois equipamentos estudados. Os equipamentos anestésicos e a adição do HME afetaram os níveis de umidade ofertados ao paciente durante a anestesia geral, e essas mudanças influenciaram a transportabilidade do muco respiratório / Background: In patients who are intubated, the natural mechanism of gas climatization by the nose and the upper airway is bypassed. During anesthesia, when the inspiratory gases are cold and dry, humidification of gases is recommended to prevent drying of the mucosal epithelium and respiratory secretions. The anesthesia systems have inherent humidifying properties as a result of the valvular rebreathing of some of the expired humidity and of the production of water in the CO2 absorber. However, the level of moisture in anesthetic ventilation is critically dependent on several factors that include the equipment, the arrangement of the circle breathing system and the fresh gas flow. To date the effect of humidity on respiratory mucus properties and transportability was not investigated. Objectives: The objective of this study was to measure the humidity and temperature of the inspired gas from a circle absorber system in two different ventilators (Dräger and Takaoka) and the effect of a heat and moisture exchanger (HME) on the inspired gas. Furthermore, we also evaluated the impact of humidity on in vitro mucus transportability and physical properties. Methods: We studied 44 patients with no pulmonary disease scheduled for elective surgery that were randomly allocated in four groups according to the anesthetic equipment (Dräger or Takaoka) and the absence or presence of HME. Respiratory mucus was collected and Temperature (T), absolute humidity (AH), relative humidity (RH) of inspired gases were recorded immediately after intubation (T0) and every 2 hours. In vitro respiratory mucus was studied by mucociliary transportability (MCT) by the frog palate method; cough clearance (CC) by the cough equipment, and contact angle (CA) by direct observation. Results: Dräger equipment delivered significantly higher levels of RH and AH when compared to Takaoka. The addition of HME increased AH and T in both equipments. RH was improved only in the Takaoka equipment. MCT, CC showed a non-significant trend to be higher in the group that provided the highest humidity (i.e Dräger + HME). CA did not change among groups. Longitudinal analysis showed that MCT was positively affected by an increase in AH and RH. CC was positively affected by the addition of HME. Conclusion: Our results showed that Dräger equipment was more effective in humidifying anesthetic gas than Takaoka. The performance of both equipments was improved when HME was added. The anesthetic equipment and the addition of HME affect the humidity delivered to the patient that in turn influences in vitro respiratory mucus transportability

Indiana University-Purdue University Indianapolis (IUPUI) / Carbon nanomaterials are widely produced and used in industry, medicine and scientific research. To examine the impact of exposure to nanoparticles on human health, the human airway epithelial cell line, Calu-3, was used to evaluate changes in the cellular proteome that could account for alterations in cellular function of airway epithelia after 24 h exposure to 10 μg/mL and 100 ng/mL of two common carbon nanoparticles, singleand multi-wall carbon nanotubes (SWCNT, MWCNT). After exposure to the nanoparticles, label-free quantitative mass spectrometry (LFQMS) was used to study differential protein expression. Ingenuity Pathway Analysis (IPA) was used to conduct a bioinformatics analysis of proteins identified by LFQMS. Interestingly, after exposure to a high concentration (10 μg/mL; 0.4 μg/cm2) of MWCNT or SWCNT, only 8 and 13 proteins, respectively, exhibited changes in abundance. In contrast, the abundance of hundreds of proteins was altered in response to a low concentration (100 ng/mL; 4 ng/cm2) of either CNT. Of the 281 and 282 proteins that were significantly altered in response to MWCNT or SWCNT, respectively, 231 proteins were the same. Bioinformatic analyses found that the proteins common to both kinds of nanotubes are associated with the cellular functions of cell death and survival, cell-to-cell signaling and interaction, cellular assembly and organization, cellular growth and proliferation, infectious disease, molecular transport and protein synthesis. The decrease in expression of the majority proteins suggests a general stress response to protect cells. The STRING database was used to analyze the various functional protein networks. Interestingly, some proteins like cadherin 1 (CDH1), signal transducer and activator of transcription 1 (STAT1), junction plakoglobin (JUP), and apoptosis-associated speck-like protein containing a CARD (PYCARD), appear in several functional categories and tend to be in the center of the networks. This central positioning suggests they may play important roles in multiple cellular functions and activities that are altered in response to carbon nanotube exposure. To examine the effect of nanotubes on the plasma membrane, we investigated the interaction of short purified MWCNT with model lipid membranes using a planar bilayer workstation. Bilayer lipid membranes were synthesized using neutral 1, 2-diphytanoylsn-glycero-3-phosphocholine (DPhPC) in 1 M KCl. The ion channel model protein, Gramicidin A (gA), was incorporated into the bilayers and used to measure the effect of MWCNT on ion transport. The opening and closing of ion channels, amplitude of current, and open probability and lifetime of ion channels were measured and analyzed by Clampfit. The presence of an intermediate concentration of MWCNT (2 μg/ml) could be related to a statistically significant decrease of the open probability and lifetime of gA channels. The proteomic studies revealed changes in response to CNT exposure. An analysis of the changes using multiple databases revealed alterations in pathways, which were consistent with the physiological changes that were observed in cultured cells exposed to very low concentrations of CNT. The physiological changes included the break down of the barrier function and the inhibition of the mucocillary clearance, both of which could increase the risk of CNT’s toxicity to human health. The biophysical studies indicate MWCNTs have an effect on single channel kinetics of Gramicidin A model cation channel. These changes are consistent with the inhibitory effect of nanoparticles on hormone stimulated transepithelial ion flux, but additional experiments will be necessary to substantiate this correlation.