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Henri Lefebvre’s concepts of everyday life and revolution The aim of this article is to analyse the concept of everyday life, which was used by Henri Lefebvre to build his theory of overcoming the alienation – both on the individual (as the theory of moments) and collective (in his concept of revolution as a popular festival) level. In the basic structures of everyday life Lefebvre saw the fundaments of spontaneity, human creative power that is capable of forcing its way through the alienating structures and that makes the total subjugation impossible. Moreover, placing the theory of revolution inside the concept of everyday life allows to draw particular attention to the importance of human consciousness in a revolutionary struggle. In the end, however, it seems that the categories introduced by Lefebvre, even though they create a good fundament for the discussion about the possibility of the human emancipation, cannot fully explain the phenomenon of the revolution.

BackgroundThree-dimensional (3D) structured organoids are the most advanced in vitro models for studying human health effects, but they have been applied only once to evaluate the biological effects associated with microplastic exposure. Fibers from synthetic clothes and fabrics are a major source of airborne microplastics, and their release from dryer machines is still poorly understood.ObjectivesIn this study, we aimed to establish an in vitro organoid model of human lung epithelial cells to evaluate its suitability for studying the effects of airborne microplastic contamination on humans. Furthermore, we aimed to characterize the microplastic fibers (MPFs) released in the exhaust filter of a household dryer and to test their interactions and inflammatory effects on the established lung organoids.MethodsThe polyester fibers emitted from the drying of synthetic fabrics were collected. Morphological characterization of the fibers released into the air filter was performed by optical microscopy and scanning electron microscopy (SEM)/energy dispersive x-ray spectroscopy (EDS). The organoids were exposed to various MPF concentrations (1, 10, and 50 mg L−1) and analyzed by optical microscopy, SEM, and confocal microscopy. Gene expression analysis of lung-specific genes, inflammatory cytokines, and oxidative stress-related genes was achieved by quantitative reverse transcription–polymerase chain reaction (qRT-PCR).ResultsWe successfully cultured organoids with lung-specific genes. The presence of MPFs did not inhibit organoid growth, but polarized cell growth was observed along the fibers. Moreover, the MPFs did not cause inflammation or oxidative stress. Interestingly, the MPFs were coated with a cellular layer, resulting in the inclusion of fibers in the organoid.DiscussionThis work could have potential long-term implications regarding lung epithelial cells undergoing repair. This preliminary exposure study using human lung organoids could form the basis for further research regarding the toxicological assessment of emerging contaminants such as micro- or nanoplastics.

Over the last 8 years, we have developed and evaluated a continuous-flow total artificial heart (CFTAH) comprising two rotary blood pumps. To understand the physiologic effects of nonpulsatile circulation, we evaluated the CFTAH in 65 calves for 90 days or less. We describe our experience with 29 calves that survived for 7 days or more. The calves received dual axial-flow (n = 24) or centrifugal-flow (n = 5) pumps. Several iterations of customized atrial cuffs were developed to facilitate an adequate anatomical fit. Pressures (arterial pressure [AoP], pulmonary artery pressure [PAP], left atrial pressure [LAP], and right atrial pressure [RAP]) and pump parameters were continuously monitored. Hematologic and biochemistry values were analyzed. After each case, a necropsy was performed. The calves survived for 7-92 days (mean, 24 days). Pressures were 94 ± 14 (AoP), 25 ± 8 (PAP), 14 ± 6 (RAP), and 16 ± 6 (LAP) mm Hg. Pump flow was maintained at 9.1 ± 1.7 L/minute (right) and 9.4 ± 1.9 L/minute (left). Hematologic and biochemistry values remained acceptable. Eight animals underwent treadmill evaluations, in which oxygen consumption (VO2) was comparable with physiologic total-body VO2. In the two animals that survived to 90 days, the end-organs appeared unremarkable at autopsy, and the CFTAH circuits were free of thrombus. Our results show that a CFTAH can maintain a large animal physiologically and hemodynamically for up to 90 days with continuous flow.

We evaluated the effects of steady state flow and perfusion on end-organ function in a long-term calf model. The animal received a continuous-flow total artificial heart (CFTAH) that we created from two axial-flow ventricular assist devices. Pump flow, blood pressure, and other pump parameters were monitored throughout the study, as were arterial blood gas and hematologic values, including neurohormone levels. Some hematologic values were mildly abnormal transiently after surgery but returned to acceptable levels within the first week. During the 90-day study, the calf showed no signs of hemolysis or thrombosis. Its mental function remained normal, as evidenced by the animal's interest in its surroundings and response to stimuli. End-organ and vasomotor function was not adversely affected by 90 days of steady state flow. This was the first study in which CFTAH support of an animal model was maintained for this duration.

Although current continuous-flow total artificial hearts (CFTAHs) are much smaller than previous models, venous kinking may still occur after device implantation, especially in smaller animals. By inserting a self-expanding stent at the site of venous narrowing in a sheep model implanted with a CFTAH, we were able to restore the normal venous geometry and dramatically increase the CFTAH output. Because this percutaneous approach avoids the challenges associated with reoperation in these cases, it may be useful to other CFTAH investigators.

OBJECTIVE: To increase applicability and stability of aortic valve repair, a three-dimensional aortic annuloplasty ring has been developed for intra-annular placement. The goal of this study was to test the safety of this device with in vivo implantation in the calf model. METHODS: In 10 chronic calves, the HAART annuloplasty ring was sutured to the aortic valve annulus using cardiopulmonary bypass. The animals were recovered and followed for 1–2 months. Serial echocardiography was used to evaluate valve competence, and contrast aortograms and CT angiograms were obtained in selected animals. After completion of follow-up, each animal was euthanized, and aortic endoscopy was performed under water distension in five. Full autopsies with histologic examinations were performed. RESULTS: All animals survived surgery. Two were euthanized in the first week for complications, and the remaining eight calves were followed uneventfully for the 1–2 months. Serial echocardiography showed completely competent valves in all but one animal, in which the ring was intentionally up-sized to test the sizing strategy. Contrast aortographic and CT angiographic findings were similar to the echocardiograms. Postmortem examination showed proper seating of all rings with endothelialization at 1–2 months. All valves demonstrated good leaflet coaptation and no abnormalities. CONCLUSIONS: In vivo testing of a three-dimensional aortic annuloplasty ring in a chronic calf model proved to be very successful and safe. Using the sizing and implant strategies developed, human trials seem indicated.

Chronic ventilatory support may be required for survival after total artificial heart (TAH) implantation in calves. However, prolonged or repeated intubation may negatively affect a calf's ability to eat, drink, ruminate, and stand after surgery. To mitigate these limitations, we performed tracheotomies on 23 consecutive calves at the time of TAH implantation. The tracheostomies served as the primary route for ventilatory support and airway management. Tracheostomies were left in place for up to 25 days (mean, 7 +/- 7 days) and were well tolerated. Prolonged presence of a tracheostomy facilitated cleaning of the airway secretions and did not inhibit the calf's ability to stand, eat, or drink. The calves survived from 2 to 49 days (mean, 8 days). Twenty-two calves that maintained their tracheostomies died of causes unrelated to airway management. The calf that had the tracheostomy removed on day 25 died of respiratory arrest on day 49. At necropsy, we found that severe tracheal stenosis had developed at the tracheostomy site. In calves, an elective tracheotomy can be a valuable adjunct to TAH implantation or other procedures that might require prolonged ventilatory support or airway access, but care should be exercised if the tracheostomy is removed to ensure that the calf does not develop late tracheal stenosis.