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Varela Armas, Luz. « Recensión : Héctor Cajaraville Araújo, Os xogos de palabras na prensa gratuíta en galego : De Luns a Venres ». Revista Galega de Filoloxía 18 (12 décembre 2017) : 177–82. http://dx.doi.org/10.17979/rgf.2017.18.0.3189.
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Recensión: Héctor Cajaraville Araújo, Os xogos de palabras na prensa gratuíta en galego: De Luns a Venres, Santiago de Compostela: Universidade de Santiago de Compostela, Servizo de Publicacións e Intercambio Científico, 2015, 216 páxinas.
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Forster, Anne, Kirste Mellish, Amanda Farrin, Bipin Bhakta, Allan House, Jenny Hewison, Jenni Murray et al. « Development and evaluation of tools and an intervention to improve patient- and carer-centred outcomes in Longer-Term Stroke care and exploration of adjustment post stroke : the LoTS care research programme ». Programme Grants for Applied Research 2, no 6 (décembre 2014) : 1–224. http://dx.doi.org/10.3310/pgfar02060.
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BackgroundEvidence-based care pathways are required to support stroke patients and their carers in the longer term.AimsThe twofold aim of this programme of four interlinking projects was to enhance the care of stroke survivors and their carers in the first year after stroke and gain insights into the process of adjustment.Methods and resultsWe updated and further refined a purposely developed system of care (project 1) predicated on a patient-centred structured assessment designed to address areas of importance to patients and carers. The structured assessment is linked to evidence-based treatment algorithms, which we updated using a structured protocol: reviewing available guidelines, Cochrane reviews and randomised trials. A pragmatic cluster randomised controlled trial evaluation of the clinical effectiveness and cost-effectiveness of this system of care was undertaken in 29 community-based UK stroke care co-ordinator services (project 2). In total, 15 services provided the system of care and 14 continued with usual practice. The primary objective was to determine whether the intervention improved patient psychological outcomes (General Health Questionnaire-12) at 6 months; secondary objectives included functional outcomes for patients, outcomes for carers and cost-effectiveness, as measured through self-completed postal questionnaires at 6 and 12 months. A total of 800 patients and 208 carers were recruited; numbers of participants and their baseline characteristics were well balanced between intervention and control services. There was no evidence of statistically significant differences in primary or secondary end points or adverse events between the two groups, nor evidence of cost-effectiveness. Intervention compliance was high, indicating that this is an appropriate approach to implement evidence into clinical practice. A 22-item Longer-term Unmet Needs after Stroke (LUNS) questionnaire was developed and robustly tested (project 3). A pack including the LUNS questionnaire and outcome assessments of mood and social activity was posted to participants 3 or 6 months after stroke to assess acceptability and validity. The LUNS questionnaire was re-sent 1 week after return of the first pack to assess test–retest reliability. In total, 850 patients were recruited and the acceptability, validity and test–retest reliability of the LUNS questionnaire as a screening tool for post-stroke unmet need were confirmed. This tool is now available for clinical use. An in-depth qualitative investigation was undertaken with 22 patients (and carers) at least 1 year after stroke (project 4) to gain further insights into the experience of adjustment. This included initial semistructured interviews, limited observations and solicited diaries with a follow-up interview 3–4 months after the initial interview and highlighted a range of different trajectories for post-stroke recovery.ConclusionsThe programme has been completed as planned, including one of the largest ever stroke rehabilitation trials. This work highlights that successfully addressing the needs of a heterogeneous post-stroke population remains problematic. Future work could explore stratifying patients and targeting services towards patients (and carers) with specific needs, leading to a more specialised bespoke service. The newly developed LUNS questionnaire and the qualitative work will help inform such services.Trial registrationCurrent Controlled Trials ISRCTN67932305.FundingThe National Institute for Health Research (NIHR) Programme Grants for Applied Research programme. The Bradford Teaching Hospitals NHS Foundation Trust received additional funding for project 2 in the submitted work from the Stroke Association, reference number TSA 2006/15. The initial development work for the LUNS tool and the Longer-Term Stroke care (LoTS care) trial carried out before the start of the programme grant was funded by the Stroke Association, reference number TSADRC 2006/01.
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Forster, Anne, Jenni Murray, John Young, Rosie Shannon, Kirste Mellish, Mike Horton, Alan Tennant et al. « Validation of the Longer-term Unmet Needs after Stroke (LUNS) monitoring tool : a multicentre study ». Clinical Rehabilitation 27, no 11 (20 juin 2013) : 1020–28. http://dx.doi.org/10.1177/0269215513487082.
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Klöpping, Ineke, Wiel Maertzdorf et Carlos Blanco. « 155 LONG TERH EFFECTS OF SUSTAINED INFLATIONS (SI) ON LUNS FUNCTION IN PRETERM NEWBORN LAMBS ». Pediatric Research 28, no 3 (septembre 1990) : 303. http://dx.doi.org/10.1203/00006450-199009000-00179.
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Litz, Heiner, Javier Gonzalez, Ana Klimovic et Christos Kozyrakis. « RAIL : Predictable, Low Tail Latency for NVMe Flash ». ACM Transactions on Storage 18, no 1 (28 février 2022) : 1–21. http://dx.doi.org/10.1145/3465406.
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Flash-based storage is replacing disk for an increasing number of data center applications, providing orders of magnitude higher throughput and lower average latency. However, applications also require predictable storage latency. Existing Flash devices fail to provide low tail read latency in the presence of write operations. We propose two novel techniques to address SSD read tail latency, including Redundant Array of Independent LUNs (RAIL) which avoids serialization of reads behind user writes as well as latency-aware hot-cold separation (HC) which improves write throughput while maintaining low tail latency. RAIL leverages the internal parallelism of modern Flash devices and allocates data and parity pages to avoid reads getting stuck behind writes. We implement RAIL in the Linux Kernel as part of the LightNVM Flash translation layer and show that it can reduce read tail latency by 7× at the 99.99th percentile, while reducing relative bandwidth by only 33%.
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Badcoe, L. M., K. G. Thompson et H. E. Pearce. « Pathological changes in the lunS of a horse which had a history of intermittent nasal bleeding after exercise ». New Zealand Veterinary Journal 40, no 1 (mars 1992) : 37. http://dx.doi.org/10.1080/00480169.1992.36521.
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Ishii, Akihiro, Yuka Thomas, Ladslav Moonga, Ichiro Nakamura, Aiko Ohnuma, Bernard M. Hang’ombe, Ayato Takada, Aaron S. Mweene et Hirofumi Sawa. « Molecular surveillance and phylogenetic analysis of Old World arenaviruses in Zambia ». Journal of General Virology 93, no 10 (1 octobre 2012) : 2247–51. http://dx.doi.org/10.1099/vir.0.044099-0.
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In order to survey arenaviruses in the Republic of Zambia, we captured 335 rodents from three cities between 2010 and 2011. Eighteen Luna virus (LUNV) and one lymphocytic choriomeningitis virus (LCMV)-related virus RNAs were detected by one-step RT-PCR from Mastomys natalensis and Mus minutoides, respectively. Four LUNV strains and one LCMV-related virus were isolated, and the whole genome nucleotide sequence was determined by pyrosequencing. Phylogenetic analyses revealed that the LUNV clade consists of two branches that are distinguished by geographical location and that the LCMV-related virus belongs to the LCMV clade, but diverges from the typical LCMVs. Comparison of nucleoprotein amino acid sequences indicated that the LCMV-related virus could be designated a novel arenavirus, which was tentatively named as the Lunk virus. Amino acid sequences of the GP, NP, Z and L proteins showed poor similarity among the three Zambian arenavirus strains, i.e. Luna, Lunk and Lujo virus.
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Poeze, Harry A. « KORTE SIGNALERINGEN ». Bijdragen tot de taal-, land- en volkenkunde / Journal of the Humanities and Social Sciences of Southeast Asia 167, no 1 (2011) : 154–66. http://dx.doi.org/10.1163/22134379-90003607.
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Francien van Anrooij, De koloniale staat 1854-1942; Gids voor het archief van het ministerie van Koloniën; De Indonesische archipel. Jan Derix, Brengers van de Boodschap; Geschiedenis van de katholieke missionering vanuit Nederland van VOC tot Vaticanum II. Bert L.T. van der Linden, Nou… tabé dan!; De ‘bootreis’ naar Indië met de Rotterdamsche Lloyd en de ‘Nederland’ tussen 1899 en 1949. Harm Stevens, Jos Stoopman en Pauljac Verhoeven (red.), De laatste Batakkoning; Koloniale kroniek in documenten 1883-1911. Meta Knol, Remco Raben en Kitty Zijlmans (red.), Beyond the Dutch; Indonesië, Nederland en de beeldende kunsten van 1900 tot nu. Hans van Wessel (eindredactie), Indische sporen; Bronnen voor lerarenopleiders. Van Nederlandsch Indië tot Indonesië. Samenstelling Hans van den Berg. 2 dvd’s, 222’. Nederlands-Indië in de Tweede Wereldoorlog. Samenstelling René Kok. Strijd om Indië; Het Nederlands-Indonesische conflict 1945-1949. Samenstelling René Kok Sjahrir, een grondlegger van het onafhankelijke Indonesië; Soetan Sjahrir 1909-1966. Den Haag: Stichting Vrienden van Linggadjati. Rita Young en Zwaan de Vries, Oorlog en overleven buiten Japanse kampen; Drie generaties vertellen… Beatrijs van Agt, Florine Koning, Esther Tak en Esther Wils, Het verborgen verhaal; Indische Nederlanders in oorlogstijd 1942-1949. Florine Koning, De Pasar Malam van Tong Tong, een Indische onderneming. Piet Sanders, Herinneringen. Wouter Meijer, ‘Ze zijn gék geworden in Den Haag’; Willem Oltmans en de kwestie Nieuw-Guinea. Edwin Oden, De man van 8 miljoen; Vriend & vijand over het fantastische leven van Willem Oltmans 1925-2004. Albert Kersten, met medewerking van Frits Bergman, Luns, een politieke biografie. Jacob Vredenbregt, Terugzien en nakaarten; Zestig jaar ooggetuige in Indonesië. Melati van Java, Fernand. Met een inleiding van Vilan van de Loo. Annie Foore, Bogoriana; Roman uit Indië. Met een inleiding van Vilan van de Loo. Mina Kruseman, Een huwelijk in Indië. Met een inleiding van Vilan van de Loo.
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Zheng, Xiaohu, Weihua Xiao et Zhigang Tian. « 869 Anti-LunX targeting therapy for lung cancer ». Journal for ImmunoTherapy of Cancer 8, Suppl 3 (novembre 2020) : A921. http://dx.doi.org/10.1136/jitc-2020-sitc2020.0869.
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BackgroundThe identification of novel therapeutic targets in lung cancer for the generation of targeted drugs is an urgent challenge. Lung-specific X (LunX) is a member of the palate, lung, and nasal epithelium clone (PLUNC) protein family. Some reports have suggested that the human PLUNC gene (also named LUNX) might be a potential marker for NSCLC, and PLUNC mRNA has been identified in peripheral blood and mediastinal lymph nodes from NSCLC patients.It is unclear whether LunX expression is associated with the pathological type and pathological severity in lung cancer patients. The utility of LunX as a potential therapeutic target in NSCLC is uncertain.MethodsClinically, 80% of lung cancers are non-small-cell lung cancers (NSCLCs). Here, we analyzed 158 NSCLC samples and detected LunX expression.ResultsIt showed that the expression of LunX were elevated in 90% (108/150) lung cancers by IHC staining, which accompanied with significantly lower rate of postsurgery survival. Further evaluation of LunX expression in invasive tumor cells in subclavicular lymph nodes, draining lymph nodes, hydrothorax of lung cancer patients, turned out that LunX is highly expressed in invasive lung cancer cells. These data indicated that LunX overexpresses in lung cancer and associates with tumorigenesis and tumor progression.Mechanistically, we discovered that LunX bound to 14-3-3 protein and facilitated their activation by maintaining these proteins in a dephosphorylated state, thereby contributing to the activation of pathways downstream of 14-3-3 protein, such as the Erk1/2 and JNK pathways. Thus, LunX promoted tumor growth and metastasis.Furthermore, we generated a therapeutic antibody specific for lung cancer, which not only inhibited lung cancer growth and reduced Ki67 staining and angiogenesis in xenograft model of subcutaneously transplanted tumor, but also blocked tumor metastasis and invasion, improved the survival of these mice. We also detected that antibody treatment induces LunX antigen-antibody complex endocytosis and the degradation of LunX protein.ConclusionsOur study suggests that LunX is a novel therapeutic target in lung cancer and that the LunX-targeted therapeutic antibody may have considerable clinical benefit.
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Joshua, Eali Stephen Neal. « LUNG NODULE SEMANTIC SEGMENTATION WITH BI-DIRECTION FEATURES USING U-INET ». Journal of Medical pharmaceutical and allied sciences 10, no 5 (15 octobre 2021) : 3494–99. http://dx.doi.org/10.22270/jmpas.v10i5.1454.
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It's difficult to detect lung cancer and determine the severity of the disease without a CT scan of the lungs. The anonymity of nodules, as well as physical characteristics such as curvature and surrounding tissue, suggest that CT lung nodule segmentation has limitations. According to the study, a new, resource-efficient deep learning architecture dubbed U-INET is required. When a doctor orders a computed tomography (CT) scan for cancer diagnosis, precise and efficient lung nodule segmentation is required. Due to the nodules' hidden form, poor visual quality, and context, lung nodule segmentation is a challenging job. The U-INET model architecture is given in this article as a resource-efficient deep learning approach for dealing with the problem. To improve segmentation operations, it also includes the Mish non-linearity functions and mask class weights. Furthermore, the LUNA-16 dataset, which included 1200 lung nodules, was heavily utilized to train and evaluate the proposed model. The U-INET architecture outperforms the current U-INET model by 81.89 times and reaches human expert level accuracy.
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Koch, Achim, Nikolaus Pizanis, Carolin Olbertz, Omar Abou-Issa, Christian Taube, Alexis Slama, Clemens Aigner, Heinz G. Jakob et Markus Kamler. « One-year experience with ex vivo lung perfusion : Preliminary results from a single center ». International Journal of Artificial Organs 41, no 8 (5 juillet 2018) : 460–66. http://dx.doi.org/10.1177/0391398818783391.
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Objective: To enlarge the donor pool for lung transplantation, an increasing number of extended criteria donor lungs are used. However, in more than 50% of multi-organ donors the lungs are not used. Ex vivo lung perfusion offers a unique possibility to evaluate and eventually recondition the injured donor lungs. The aim of our study was to assess the enlargement of the donor pool and the outcome with extended criteria donor lungs after ex vivo lung perfusion. Patients and Methods: Data were prospectively collected in our lung transplant database. We compared the results of lung transplants after ex vivo lung perfusion with those after conventional cold static preservation. In total, 11 extended criteria donor lungs processed with ex vivo lung perfusion and 41 cold static preservation lungs transplanted consecutively between May 2016 and May 2017 were evaluated. Normothermic ex vivo lung perfusion was performed according to the Toronto protocol for 4 h. Cold static preservation lungs were stored in low-potassium dextran solution. Results: Ex vivo lung perfusion lungs before procurement had significantly lower PaO2/FiO2 (P/F) ratios and more X-ray abnormalities. There were no statistically significant differences for pre-donation ventilation time, smoking history, or sex. After reconditioning with ex vivo lung perfusion, 9 out of 11 processed lungs were considered suitable and successfully transplanted. The mean postoperative ventilation time and in-hospital stay were not significantly different in ex vivo lung perfusion and cold static preservation recipients. Conclusion: Ex vivo lung perfusion can safely be used in the evaluation of lungs initially considered not suitable for transplantation. The primary outcome was not negatively affected and normothermic ex vivo lung perfusion is a useful tool to increase the usage of potentially transplantable lungs.
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Gerasimiuk, V. P., et N. V. Gerasimiuk. « FLORA OF ODESA AIRPORT FOREST PARK ». Odesa National University Herald. Biology 27, no 1(50) (25 juin 2022) : 24–36. http://dx.doi.org/10.18524/2077-1746.2022.1(50).259760.
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Introduction. The flora of the area of study included algae, fungi, lichens and higher plants (mosses, ferns, golonasinny and angiosperm). They play an important role in the ecosystem of the Airport Forest Park. Odesa, create primary organic matter, emit oxygen, dispose of carbon dioxide, enrich the soil with nitrogen substances, decompose the remains of organic substances and process them into inorganic and are food and shelter for many invertebrates (worms, mollusks, insects) and vertebrates (reptiles, birds, mammals) organisms. Aim. The purpose of the work was to study the floristic diversity of the Airport Forest Park in Odessa. Methods. For the first time, the flora of the Airport forest was investigated during 2000-2022 by the route method. Determination of the species composition of algae, fungi, lichens, higher plants was carried out by light microscopy with the help of many determinists, atlases, monographs. Results. The flora of the forest park "Airportivsky" consists of 173 species (173 inland species taxa), which belonged to 156 genera, 60 families, 37 orders, 13 classes, 10 departments, 4 kingdoms and 2 empires (domains). The flora consisted of lower (Thallophyta) and higher (Embryophyta) plants. Lower plants were represented by algae (12 species), fungi (35) and lichens (2), higher – mosses (3), ferns (1), golonosin (6) and angiosperms (114). A characteristic feature of the taxonomic diversity was the dominance of angiosperms (114 species) in the species composition of the flora of the forest park. The most represented species were the leading families Asteraceae (20 species), Rosaceae (13), Fabaceae (11), Brassicaceae (6), Poaceae (5), Oleaceae (5), Aceraceae (4), Fagaceae (2), Lamiaceae (2) and Plantaginaceae (2). Leading genera of Aser l. (4 species), Artemisia L. (4), Agaricus L. (3), Medicago L. (3), Prunus L. (3), Trifoilium L. (3), Closterium Nitsch ex Ralphs (3), Amanita Pers. (2), Lactarium Pers. (2) and Plantago L. (2) formed the basis of the flora of the forest park. The most interesting floral finds are found in the flora of the park of the following species: closterium closteroid (Closterium closterioides (Ralfs) Luns et Peweters), glass Ola (Cyathus olla (Batsch) Pers.). Conclusions. For the first time in the flora of the Airport forest found 173 species (173 inland species taxa), belonging to 156 genera, 60 families, 37 orders, 13 classes, 10 divisions, 4 kingdoms and 2 empires (domains). Among them were found 12 species of algae, 35 fungi, 2 lichens, 3 mosses, 1 fern, 6 gymnosperms and 114 species of angiosperms.
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Szpinda, Michał, Waldemar Siedlaczek, Anna Szpinda, Alina Woźniak, Celestyna Mila-Kierzenkowska et Mateusz Badura. « Quantitative Anatomy of the Growing Lungs in the Human Fetus ». BioMed Research International 2015 (2015) : 1–10. http://dx.doi.org/10.1155/2015/362781.
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Using anatomical, digital, and statistical methods we examined the three-dimensional growth of the lungs in 67 human fetuses aged 16–25 weeks. The lung dimensions revealed no sex differences. The transverse and sagittal diameters and the base circumference were greater in the right lungs while the lengths of anterior and posterior margins and the lung height were greater in the left lungs. The best-fit curves for all the lung parameters were natural logarithmic models. The transverse-to-sagittal diameter ratio remained stable and averaged0.56±0.08and0.52±0.08for the right and left lungs, respectively. For the right and left lungs, the transverse diameter-to-height ratio significantly increased from0.74±0.09to0.92±0.08and from0.56±0.07to0.79±0.09, respectively. The sagittal diameter-to-height ratio significantly increased from1.41±0.23to1.66±0.18in the right lung, and from1.27±0.17to1.48±0.22in the left lung. In the fetal lungs, their proportionate increase in transverse and sagittal diameters considerably accelerates with relation to the lung height. The lung dimensions in the fetus are relevant in the evaluation of the normative pulmonary growth and the diagnosis of pulmonary hypoplasia.
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Syed, Ahad, Sarah Kerdi et Adnan Qamar. « Bioengineering Progress in Lung Assist Devices ». Bioengineering 8, no 7 (28 juin 2021) : 89. http://dx.doi.org/10.3390/bioengineering8070089.
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Artificial lung technology is advancing at a startling rate raising hopes that it would better serve the needs of those requiring respiratory support. Whether to assist the healing of an injured lung, support patients to lung transplantation, or to entirely replace native lung function, safe and effective artificial lungs are sought. After 200 years of bioengineering progress, artificial lungs are closer than ever before to meet this demand which has risen exponentially due to the COVID-19 crisis. In this review, the critical advances in the historical development of artificial lungs are detailed. The current state of affairs regarding extracorporeal membrane oxygenation, intravascular lung assists, pump-less extracorporeal lung assists, total artificial lungs, and microfluidic oxygenators are outlined.
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Khubutiya, M. Sh, A. M. Gasanov, E. A. Tarabrin, T. V. Chernen’kaya, T. E. Kallagov et E. I. Pervakova. « A comparison of airway microbiota in donors and recipients of lung transplants ». Russian Pulmonology 29, no 2 (1 juillet 2019) : 184–88. http://dx.doi.org/10.18093/0869-0189-2019-29-2-184-188.
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This study was aimed at investigation of relationships between bronchial washing culture in post-transplant recipient and bronchial flora of the lung donor. Methods. A comparative analysis of bronchial washing cultures from 30 post-transplant lung recipients was performed. All lung donors were stratified to ideal, suboptimal and marginal donors according to the lung transplant suitability. Results. As a result, development of post-transplant pulmonary complications was directly related to bacterial flora of the donor lung. The incidence of pneumonia in post-transplant patients was 3.3% after transplantation of ideal donor lungs, 20% after transplantation of suboptimal donors lungs and 100% after transplantation of marginal donor lungs. Conclusion. The rate of pneumonia in transplanted lungs was directly related to bronchial flora in the donor lungs. This should be taken into account when planning antibacterial therapy after lung transplantation.
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Pronych, Scott, et Richard Wassersug. « Lung use and development in Xenopus laevis tadpoles ». Canadian Journal of Zoology 72, no 4 (1 avril 1994) : 738–43. http://dx.doi.org/10.1139/z94-099.
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Shortly after hatching, Xenopus laevis tadpoles fill their lungs with air. We examined the role played by early lung use in these organisms, since they are able to respire with both their lungs and their gills. We investigated the effect on X. laevis development when the larvae were prevented from inflating their lungs, and whether early lung use influenced the size of the lungs or the tadpole's ability to metamorphose. Tadpoles that were denied access to air had lungs one-half the size of those of controls. This difference in lung size was too large to be explained merely by a stretching of the lung due to inflation. The longer tadpoles were denied access to air, the longer they took to metamorphose, and their probability of completing metamorphosis diminished. One tadpole raised throughout its larval life without access to air successfully metamorphosed but had abnormal, solidified lungs and an enlarged heart. Collectively, these experiments demonstrate that early lung use in tadpoles is important in determining both ultimate lung size and the probability of successfully metamorphosing. Lung use during early larval development in X. laevis is not absolutely necessary for survival through metamorphosis, but its absence severely handicaps growth.
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Abernathy, V. J., N. A. Pou, R. E. Parker et R. J. Roselli. « Evaluation of perilla ketone-induced unilateral lung injury using external gamma scanning ». Journal of Applied Physiology 76, no 1 (1 janvier 1994) : 138–45. http://dx.doi.org/10.1152/jappl.1994.76.1.138.
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We used a modified external gamma scanning technique to quantitate right and left lung permeability changes to iodinated sheep albumin before and after perilla ketone (PK)-mediated unilateral lung injury in seven anesthetized sheep. Three portable gamma scintillation probes containing 2-in. NaI crystals detected radioactivities of 51Cr-labeled red blood cells and 125I-labeled albumin over the right and left lungs and blood, respectively. Radioactivities were monitored for 1 h before and 3 h after infusion of 25 mg/kg PK into a single lung. Calculation of normalized slope index (NSI) (Roselli and Riddle, J. Appl. Physiol. 67: 2343–2350, 1989) over the 30-min interval before PK and over the 60- to 90-min interval after PK for each lung revealed a four- to five-fold NSI increase in lungs receiving PK (0.00237 +/- 0.00065 to 0.0109 +/- 0.0016 min-1) and no increase in contralateral control lungs (0.00214 +/- 0.00065 to 0.00201 +/- 0.00032 min-1). Observed changes in NSI were consistent with postmortem evaluations of each lung. Lungs receiving PK had significantly higher wet-to-dry lung weight ratios and extravascular lung water volumes than contralateral control lungs. Measured bloodless wet-to-dry lung weight ratios were 5.68 +/- 0.39 and 3.27 +/- 0.27 (P < 0.05) for PK and control lungs, respectively.
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James, A., G. Pearce-Pinto et D. Hillman. « Effects of lung volume and surface forces on maximal airway smooth muscle shortening ». Journal of Applied Physiology 77, no 4 (1 octobre 1994) : 1755–62. http://dx.doi.org/10.1152/jappl.1994.77.4.1755.
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The effects of lung volume and surface forces on airway smooth muscle shortening were studied in isolated perfused rat lungs. The lungs were inflated via the trachea with gas or Krebs solution (n = 12 each) to volumes equivalent to gas inflation pressures of 5 (low), 15 (medium), and 25 (high) cmH2O (n = 4 each). At each volume, two of the four lungs were perfused with methacholine (10(-2) M) and then all were perfused with Formalin for fixation. The amount of smooth muscle shortening present in transverse sections of the airways was determined by comparing the observed outer perimeter of the smooth muscle layer with its calculated relaxed perimeter. In the control lungs, mean shortening was < or = 10% in all groups except the liquid-filled lungs at low lung volumes [33 +/- 12% (SD)]. In the methacholine-stimulated lungs, mean shortening was between 45 and 56% at medium and low lung volumes in gas- and liquid-filled lungs, respectively, and approximated the degree of shortening required to cause airway closure. At high lung volume, less shortening was observed in the methacholine-stimulated lungs, either liquid (34 +/- 17%) or gas filled (16 +/- 19%; P < 0.05 compared with liquid filled). The effects of lung volume in liquid-filled lungs and the differences in response between gas- and liquid-filled lungs demonstrate, respectively, that both lung tissue recoil and surface forces act to oppose shortening of maximally stimulated smooth muscle.(ABSTRACT TRUNCATED AT 250 WORDS)
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Bryan, C. L., A. J. Patefield, D. Cohen, J. L. Nielsen, B. Emanuel et J. H. Calhoon. « Assessment of injury in transplanted and nontransplanted lungs after 6 h of cold storage with glutathione ». Journal of Applied Physiology 76, no 3 (1 mars 1994) : 1232–41. http://dx.doi.org/10.1152/jappl.1994.76.3.1232.
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Single-lung transplantation after 3 h of hypothermic storage produces bilateral lung injury [pulmonary reimplantation response (PRR)]. We hypothesized that glutathione (GSH) hypothermic storage would protect both lungs from PRR for extended preservation times and that differences in injury and protection would be realized between the graft and the nontransplanted lung. Mongrel dogs underwent left single-lung autotransplantation after preservation for 5–6 h in Euro-Collins (EC) solution, EC plus exogenous GSH (EC+GSH), or Viaspan (VIA) at 4 degrees C. Lung injury was measured in both lungs after 1 h of reperfusion. EC dogs demonstrated significant increases in lung edema, lipid peroxidation, and alveolar neutrophil recruitment in the lung graft and to a less extent in the nontransplanted right lung compared with control dogs (P < 0.05). Edema, lipid peroxidation, and alveolar neutrophils were significantly reduced in both lungs from EC+GSH and VIA dogs compared with lungs from EC dogs (P < 0.05). An increase in large-pore permeability was measured in the lung graft from EC dogs compared with all other lungs. Bronchoalveolar lavage fluid lactate dehydrogenase and total protein concentrations were elevated in both lungs from all three groups of tranplanted dogs compared with those of control dogs (P < 0.05). These data suggest that GSH-containing solutions attenuate the PRR after 6 h of ischemic hypothermic storage but that the protection is incomplete. Mechanisms of injury affecting the lung graft during the PRR appear to differ from those affecting the nontransplanted lung.
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Jackson, R. M., W. J. Russell et C. F. Veal. « Endogenous and exogenous catalase in reoxygenation lung injury ». Journal of Applied Physiology 72, no 3 (1 mars 1992) : 858–64. http://dx.doi.org/10.1152/jappl.1992.72.3.858.
Texte intégralRésumé :
Reexpansion pulmonary edema parallels reperfusion (reoxygenation) injuries in other organs in that hypoxic and hypoperfused lung tissue develops increased vascular permeability and neutrophil infiltration after reexpansion. This study investigated endogenous lung catalase activity and H2O2 production during hypoxia (produced by lung collapse) and after reoxygenation (resulting from reexpansion), in addition to assessing the effects of exogenous catalase infusion on the development of unilateral pulmonary edema after reexpansion. Lung collapse resulted in a progressive increase in endogenous catalase activity after 3 (14%) and 7 days (23%), while activities in contralateral left lungs did not change (normal left lungs averaged 180 +/- 11 units/mg DNA). Tissue from control left lungs released H2O2 into the extracellular medium at a rate calculated to be 242 +/- 34 nmol.h-1.lung-1. No significant change in extracellular release of H2O2 occurred after 7 days of right lung collapse. However, after reexpansion of the previously collapsed right lungs for 2 h, H2O2 release from both reexpanded right and contralateral left lungs significantly increased (88 and 60%, respectively) compared with controls. Infusion of exogenous catalase significantly increased plasma and lung catalase activities. Exogenous catalase infusion prevented neither the increase in lung permeability nor the infiltration with neutrophils that typically occurs in reexpanded lungs. These data indicate that lung hypoxia/reoxygenation, induced by sequential collapse and reexpansion, has specific effects on endogenous lung catalase activity and H2O2 release. However, exogenous catalase does not prevent reexpansion pulmonary edema, eliminating extracellular (but not intracellular) H2O2 as an important mediator of unilateral lung injury in this model.
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Chen, C. R., N. F. Voelkel et S. W. Chang. « PAF potentiates protamine-induced lung edema : role of pulmonary venoconstriction ». Journal of Applied Physiology 68, no 3 (1 mars 1990) : 1059–68. http://dx.doi.org/10.1152/jappl.1990.68.3.1059.
Texte intégralRésumé :
We studied the synergistic interaction between platelet-activating factor (PAF) and protamine sulfate, a cationic protein that causes pulmonary endothelial injury, in isolated rat lungs perfused with a physiological salt solution. A low dose of protamine (50 micrograms/ml) increased pulmonary artery perfusion pressure (Ppa) but did not increase wet lung-to-body weight ratio after 20 min. Pretreatment of the lungs with a noninjurious dose of PAF (1.6 nM) 10 min before protamine markedly potentiated protamine-induced pulmonary vasoconstriction and resulted in severe lung edema and increased lung tissue content of 6-keto-prostaglandin F1 alpha, thromboxane B2, and leukotriene C4. Pulmonary microvascular pressure (Pmv), measured by double occlusion, was markedly increased in lungs given PAF and protamine. These potentiating effects of PAF were blocked by WEB 2086 (10(-5) M), a specific PAF receptor antagonist. Pretreatment of the lungs with a high dose of histamine (10(-4) M) failed to enhance the effect of protamine on Ppa, Pmv, or wet lung-to-body weight ratio. Furthermore, PAF pretreatment enhanced elastase-, but not H2O2-, induced lung edema. To assess the role of hydrostatic pressure in edema formation, we compared lung permeability-surface area products (PS) in papaverine-treated lungs given either protamine alone or PAF + protamine and tested the effect of mechanical elevation of Pmv on protamine-induced lung edema. In the absence of vasoconstriction, PAF did not potentiate protamine-induced increase in lung PS. On the other hand, mechanically raising Pmv in protamine-treated lungs to a level similar to that measured in lungs given PAF + protamine did not result in a comparable degree of lung edema. We conclude that PAF potentiates protamine-induced lung edema predominantly by enhanced pulmonary venoconstriction. However, a pressure-independent effect of PAF on lung vasculature cannot be entirely excluded.
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Roshankhah, Roshan, John Blackwell, Hong Yuan, Stephanie A. Montgomery, Thomas M. Egan et Marie Muller. « Investigating response to treatment of pulmonary fibrosis in rats using ultrasound multiple scattering ». Journal of the Acoustical Society of America 151, no 4 (avril 2022) : A76. http://dx.doi.org/10.1121/10.0010708.
Texte intégralRésumé :
Lung alveoli constitute a complex distribution of strong ultrasound scatterers, leading to multiple scattering (USMS). Conventional ultrasound cannot be utilized to produce images that would accurately render lung structure. Pulmonary fibrosis affects lung microstructure by thickening alveolar walls, which changes wave diffusion and scattering patterns by modifying the distribution and size of scatterers. We present a method for the quantitative approach of structural changes in lung parenchyma based on diffusion of ultrasound waves, relying on measurement of the scattering mean free path (SMFP). We quantify severity of lung damage due to bleomycin-induced fibrosis in rats, and to monitor response to Nintedanib treatment by comparing the SMFP in 6 control (normal) lungs, 6 fibrotic lungs, and 6 fibrotic lungs from rats treated with Nintedanib. We observed significant differences in SMFP among control lungs (483 ± 50 μm), fibrotic lungs (1433 ± 612 μm), and lungs from Nintedanib-treated rats (835 ± 149 μm) (mean ± sd). Strong correlations were observed between SMFP and fibrosis severity score on inflated ex vivo CT lung images (p = 0.076, r = 0.43), as well as between SMFP and modified Ashcroft score of inflation-fixed lungs stained with H&E and Sirius red (p = 0.008, r = 0.61). This suggests SMFP may be useful to monitor response to treatment of pulmonary fibrosis.
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Farrelly, C., et P. Greenaway. « GAS EXCHANGE THROUGH THE LUNGS AND GILLS IN AIR-BREATHING CRABS ». Journal of Experimental Biology 187, no 1 (1 février 1994) : 113–30. http://dx.doi.org/10.1242/jeb.187.1.113.
Texte intégralRésumé :
Lung and gill performance in gas exchange have been evaluated in eight species of air-breathing crabs with two different lung circulatory designs, those with portal systems and smooth lung linings, and those without portal systems and with invaginated and evaginated lung linings. In all species, the lungs were extremely effective in oxygen uptake whilst the performance of the gills was inferior. An exception to this was Gecarcoidea natalis, which has gills highly modified for aerial gas exchange; its gills and lungs were equally efficient in O2 uptake. The relative efficiencies of the lungs and gills in CO2 excretion differed between species, with the gills being the major site of CO2 loss in the more amphibious species and the lungs having an increasingly important role in the more terrestrial crabs. The presence or absence of lung portal systems was not found to correlate with either saturation rates or efferent oxygen concentrations, with both lung types being extremely efficient in O2 uptake. The lungs with portal systems showed a large increase in oxygen content in the first lacunar bed and progressively smaller increases in the next two; these lungs may, therefore, have some reserve for exercise.
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Levvey, Bronwyn, Kovi Levin, Miranda Paraskeva, Glen Westall et Gregory Snell. « Donation after Brain Death versus Donation after Circulatory Death : Lung Donor Management Issues ». Seminars in Respiratory and Critical Care Medicine 39, no 02 (26 mars 2018) : 138–47. http://dx.doi.org/10.1055/s-0037-1615820.
Texte intégralRésumé :
AbstractLung transplantation (LTx) has traditionally been limited by a lack of suitable donor lungs. With the recognition that lungs are more robust than initially thought, the size of the donor pool of available lungs has increased dramatically in the past decade. Donation after brain death (DBD) and donation after circulatory death (DCD) lungs, both ideal and extended are now routinely utilized. DBD lungs can be damaged. There are important differences in the public's understanding, legal and consent processes, intensive care unit strategies, lung pathophysiology, logistics, and potential-to-actual donor conversion rates between DBD and DCD. Notwithstanding, the short- and long-term outcomes of LTx from any of these DBD versus DCD donor scenarios are now similar, robust, and continue to improve. Large audits suggest there remains a large untapped pool of DCD (but not DBD) lungs that may yet further dramatically increase lung transplant numbers. Donor scoring systems that might predict the donor conversion rates and lung quality, the role of ex vivo lung perfusion as an assessment and lung resuscitation tool, as well as the potential of donor lung quality biomarkers all have immense promise for the clinical field.
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Nelson, PG, et AM Perks. « Effects of lung expansion on lung liquid production in vitro by lungs from fetal guinea-pigs. II. Evidence for generation of an inhibitory factor ». Reproduction, Fertility and Development 8, no 3 (1996) : 347. http://dx.doi.org/10.1071/rd9960347.
Texte intégralRésumé :
Lungs from near-term fetal guinea-pigs were supported in vitro for 3 h; lung liquid production was measured by a dye-dilution method using Blue Dextran 2000 [fetuses 63 +/- 2 days of gestation, 97.6 +/- 19.8 (SD) g body weight]. Preparations were incubated in pairs taken from the same mother. Twenty lungs incubated in pairs without treatment (controls) showed no significant changes in fluid production throughout incubation (analysis of variance; regression analysis); rates in successive hours were: first lung, 1.36 +/- 0.39, 1.09 +/- 0.34 and 1.27 +/- 0.42 ml/kg body weight per h; second lung, 1.46 +/- 0.52, 1.09 +/- 0.41 and 1.18 +/- 0.43 ml/kg body weight per h. Twenty lungs were incubated similarly in pairs, but after one hour one lung from each pair was expanded with Krebs-Henseleit saline in volumes approximating those of the first breath (68 +/- 10% of lung volume). The expanded lungs began to reabsorb fluid immediately after expansion; the untreated lungs also stopped production or reached reabsorption by the final hour. Rates in successive hours were: expanded lungs; before expansion, 1.00 +/- 0.21, after expansion, -0.23 +/- 0.17 and 0.14 +/- 0.09 ml/kg body weight per h; unexpanded lungs, 1.27 +/- 0.49, 0.02 +/- 0.01 and -0.01 +/- 0.004 ml/kg body weight per h. The decrease in production was significant for each type of lung. The effects persisted in both expanded and unexpanded lungs in the presence of 1.78 x 10(-5) M phentolamine (n = 12; 70 +/- 2% expansion). The results suggest that expansion of the lungs at birth may release an unknown inhibitory factor, provisionally termed Expansion Factor (EF), within the lungs; this agent, probably not a catecholamine, can change lung fluid production into reabsorption and may partly account for the failure of beta-antagonists to prevent fluid reabsorption at delivery.
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Cutillo, A. G., K. C. Goodrich, K. Ganesan, S. Watanabe, D. C. Ailion, K. H. Albertine, A. H. Morris et C. H. Durney. « Lung water measurement by nuclear magnetic resonance : correlation with morphometry ». Journal of Applied Physiology 79, no 6 (1 décembre 1995) : 2163–68. http://dx.doi.org/10.1152/jappl.1995.79.6.2163.
Texte intégralRésumé :
Estimates of lung water content obtained from nuclear magnetic resonance (NMR) and morphometric and gravimetric measurements were compared in normal and experimentally injured rats. Average lung water density (rho H2O) was measured by an NMR technique in excised unperfused rat lungs (20 normal lungs and 12 lungs with oleic acid-induced edema) at 0 (full passive deflation) and 30 cmH2O lung inflation pressure and in vivo (4 normal rats and 8 rats with lung injury induced by oleic acid or rapid saline infusion). The rho H2O values were compared with morphometric measurements of lung tissue volume density (Vv) obtained from the same lungs fixed at corresponding liquid-instillation pressures. A close correlation was observed between rho H2O and Vv in normal and injured excised lungs [correlation coefficient (r) = 0.910, P < 0.01]. In vivo rho H2O was also closely correlated with Vv (r = 0.897, P < 0.01). The correlation coefficients between rho H2O and gravimetric lung water content (LWGr) were lower in the excised lung group (r = 0.663 and 0.692, respectively, for rho H2O at 0 and 30 cmH2O lung inflation pressure, P < 0.01) than in the in vivo study (r = 0.857, P < 0.01). Our results indicate that NMR techniques, which are noninvasive and nondestructive, provide reliable estimates of lung water density and that the influence of lung inflation on rho H2O is important (compared with the effect of lung water accumulation in lung injury) only in the presence of deliberately induced very large variations in the lung inflation level.
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He, L. S., S. W. Chang, P. Ortiz de Montellano, T. J. Burke et N. F. Voelkel. « Lung injury in Fischer but not Sprague-Dawley rats after short-term hyperoxia ». American Journal of Physiology-Lung Cellular and Molecular Physiology 259, no 6 (1 décembre 1990) : L451—L458. http://dx.doi.org/10.1152/ajplung.1990.259.6.l451.
Texte intégralRésumé :
The Fischer rat is known for its susceptibility to develop liver necrosis when challenged with paraquat (Smith et al., J. Pharmacol. Exp. Ther. 235: 172-177, 1985). We postulated that other organs, specifically the lung, may also be more susceptible to injury and examined whether lungs from Fischer (F) rats were injured more easily when challenged with active oxygen species than Sprague-Dawley (SD) rat lungs. We aimed to investigate whether increased susceptibility to oxidant injury was related to differences in lung antioxidant defenses. Perfused lungs from both rat strains were challenged by addition of H2O2 to the perfusate or by short-term hyperoxic ventilation. To assess nonoxidant modes of lung injury, we examined lung responses after exposure to protamine sulfate or neutrophil elastase. Intravascular H2O2 or 3 h in vitro hyperoxia caused lung edema in F but not SD rats, and elastase injured F rat lungs more than the lungs from SD rats. Protamine, however, injured the lungs from both strains to a similar degree. Catalase, but not superoxide dismutase or allopurinol, protected F rat lungs against edema, resulting from 3 h in vitro hyperoxia. The lung homogenate levels for reduced glutathione or conjugated dienes and the activities of lung tissue catalase, glutathione peroxidase, and cytochrome P-450 were not different between the two strains. Lung tissue ATP levels, however, were lower in F than in SD rats. Although the F rat strain appears to have an altered oxidant-antioxidant defense balance, the exact cause of the greater susceptibility to oxidant stress of the F rat strain remains elusive.
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Stettler, L. E., S. F. Platek, D. H. Groth, F. H. Y. Green et V. Vallyathan. « Particle Contents of Human Lungs ». Proceedings, annual meeting, Electron Microscopy Society of America 43 (août 1985) : 116–19. http://dx.doi.org/10.1017/s0424820100117595.
Texte intégralRésumé :
Scanning electron microscopy (SEM) and energy dispersive x-ray analysis (EDXA) have been used by numerous investigators to study the particle content of human lungs. Most of this work has been performed on lung specimens from subjects with known or suspected lung diseases. The object of these analyses has been an attempt to relate the composition and concentration of the particles present in the lungs to the lung disease. A major factor missing from past microanalysis work has been data from typical “normal” lungs with which the analyses of diseased lungs could be compared. Currently in progress at NIOSH, is a study in which the particle contents of 96 urban lungs from the Cincinnati, Ohio area are being determined.Preliminary results for thirty-five of these lung samples will be presented and discussed in the report. When completed, the analysis data will serve as background or baseline data for typical urban lungs with which comparisons of the particle contents of diseased lungs can be made.
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Pérez-Bravo, David, Despoina Myti, Ivana Mižíková, Tilman Pfeffer, David E. Surate Solaligue, Claudio Nardiello, István Vadász et al. « A comparison of airway pressures for inflation fixation of developing mouse lungs for stereological analyses ». Histochemistry and Cell Biology 155, no 2 (29 décembre 2020) : 203–14. http://dx.doi.org/10.1007/s00418-020-01951-0.
Texte intégralRésumé :
AbstractThe morphometric analysis of lung structure using the principles of stereology has emerged as a powerful tool to describe the structural changes in lung architecture that accompany the development of lung disease that is experimentally modelled in adult mice. These stereological principles are now being applied to the study of the evolution of the lung architecture over the course of prenatal and postnatal lung development in mouse neonates and adolescents. The immature lung is structurally and functionally distinct from the adult lung, and has a smaller volume than does the adult lung. These differences have raised concerns about whether the inflation fixation of neonatal mouse lungs with the airway pressure (Paw) used for the inflation fixation of adult mouse lungs may cause distortion of the neonatal mouse lung structure, leading to the generation of artefacts in subsequent analyses. The objective of this study was to examine the impact of a Paw of 10, 20 and 30 cmH2O on the estimation of lung volumes and stereologically assessed parameters that describe the lung structure in developing mouse lungs. The data presented demonstrate that low Paw (10 cmH2O) leads to heterogeneity in the unfolding of alveolar structures within the lungs, and that high Paw (30 cmH2O) leads to an overestimation of the lung volume, and thus, affects the estimation of volume-dependent parameters, such as total alveoli number and gas-exchange surface area. Thus, these data support the use of a Paw of 20 cmH2O for inflation fixation in morphometric studies on neonatal mouse lungs.
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Horalskyi, L., N. Hlukhova et I. Sokulskyi. « Morphological traits of rabbit lung ». Scientific Horizons 93, no 8 (2020) : 180–88. http://dx.doi.org/10.33249/2663-2144-2020-93-8-180-188.
Texte intégralRésumé :
In the article, following the results of complex methods (anatomic, histologic, organometric, histometric and statistical) researches are shown the features of morphological structure and morphometric parameters of the lungs of mature rabbits. It was found out, that macro- and microscopic architecture of rabbit lungs has similar histoarchitectonics, inherent in other species of farm animals of the class "mammals" and the characteristic features of morphological structures. Lungs in clinically healthy rabbits structurally reflect the shape of thoracic cavity and gradually expand ventrally. Subsequent to the results of performed organometry, the absolute lung mass of mature rabbits is 18,05±1,32 g, relative 0,624±0,013 %. The Right and left rabbit lungs are surrounded by pleural sacs (right and left): in rabbits pleural spaces of the right and left lungs are not connected. According to morphological and organometric investigations the rabbit lungs are relating to VIII type – the reduction of the superior lobe of left lung is observed, consequently right lung is more developed than left ( the length of right lung is 6,40±0,45 mm, the width – 3,54±0,30 mm, the thickness – 3,28±0,30 mm; the length of left lung is 6,84±0,40 mm; 4,18±0,30 mm and 1,52±0,30 mm relatively) and the coefficient of lung asymmetry (right to left) according to their absolute mass is 1.16. Although, rabbit lungs have dilatated base and superior. Right lung divides into four lobes – cranial (the superior), cardio, diaphragmatic and ancilla, left one divides into three lobes – the reduced superior, cardio and diaphragmatic. Histoarchitecture of lungs is formed by lobes of the lungs, that are separated by connective tissue, which contains blood and lymphatic vessels. Lung parenchyma is created by airways and respiratory divisions that blood vessels accompany to. Respiratory lung parenchyma is formed by respiratory bronchioles, alveolar ducts and alveolar saccules, in which walls the alveolus are located and shape the alveolar tree. According to the analysis of histometry results, respiratory (breathing) lobe of lungs of experimental rabbits is 52,3± 0,62 %, connective tissue base – 69,6±1,27 %, and the average volume of alveolus (small, middle and big) is equal to 42,3±4,35 thousand mkm3.
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Hybertson, Brooks M., Roger P. Kitlowski, Eric K. Jepson et John E. Repine. « Supercritical fluid-aerosolized vitamin E pretreatment decreases leak in isolated oxidant-perfused rat lungs ». Journal of Applied Physiology 84, no 1 (1 janvier 1998) : 263–68. http://dx.doi.org/10.1152/jappl.1998.84.1.263.
Texte intégralRésumé :
Hybertson, Brooks M., Roger P. Kitlowski, Eric K. Jepson, and John E. Repine. Supercritical fluid-aerosolized vitamin E pretreatment decreases leak in isolated oxidant-perfused rat lungs. J. Appl. Physiol. 84(1): 263–268, 1998.—We hypothesized that direct pulmonary administration of supercritical fluid-aerosolized (SFA) vitamin E would decrease acute oxidative lung injury. We previously reported that rapid expansion of supercritical CO2 formed respirable particles of vitamin E and that administering SFA vitamin E to rats increased lung vitamin E levels and decreased neutrophil-mediated lung leak. In the present investigation, we found that pretreatment with SFA vitamin E protected isolated rat lungs against the oxidant-induced lung leak caused by perfusion with xanthine oxidase (XO) and purine, an enzyme system that generates superoxide anion ([Formula: see text]) and hydrogen peroxide. SFA vitamin E droplets were 0.7–3 μm in diameter, and inhalation of the airborne droplets for 30 min deposited ∼55 μg of vitamin E in rat lungs. Isolated rat lungs perfused with XO (0.02 U/ml) and purine (10 mM) gained more weight (1.75 ± 0.12 g, n = 8), retained more Ficoll (11.5 ± 1.2 mg/left lung, n = 7), and accumulated more Ficoll in their lung lavages (700 ± 146 μg/ml, n = 8) than control lungs [0.25 ± 0.06 g ( n = 10), 6.2 ± 1.2 mg/left lung ( n = 9), and 141 ± 31 μg/ml ( n = 8), respectively, P < 0.05]. In contrast, isolated lungs from rats that were pretreated with SFA vitamin E had decreased ( P < 0.05) weight gains (0.32 ± 0.06 g, n = 7), Ficoll retentions (3.3 ± 1.1 mg/left lung, n = 7), and lung lavage Ficoll concentrations (91 ± 26 μg/ml, n = 6) after perfusion with XO and purine compared with isolated lungs from control rats perfused with XO and purine. This protective effect was not observed in rat lungs given sham treatments (CO2 alone or vitamin E acetate aerosolized with supercritical CO2). Our results suggest that direct pulmonary supplementation of vitamin E decreases susceptibility to vascular leakage caused by XO-derived oxidants.
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Kirillova, E., N. Shamsutdinova et G. Nurullina. « THU0534 LUNG ULTRASOUND IN PATIENTS WITH SECONDARY INTERSTITIAL LUNG DISEASES ». Annals of the Rheumatic Diseases 79, Suppl 1 (juin 2020) : 506.2–507. http://dx.doi.org/10.1136/annrheumdis-2020-eular.5168.
Texte intégralRésumé :
Background:Currently, lung ultrasound (LUS) is increasingly used in rheumatology.Objectives:To evaluate the relationship between lung ultrasound and pulmonary function and disease activity in patients with rheumatic diseases with secondary lung involvement.Methods:Thirty patients with rheumatic diseases were included in the study, who, according to the data of the high-resolution RCT of lungs (64-slice CT system Philips Diamond Select Brilliance), showed interstitial lung involvement as a type of nonspecific interstitial pneumonia. In 4 patients, mixed connective tissue disease (MCTD) was diagnosed, 20 had systemic vasculitis (SV), and 6 had rheumatoid arthritis (RA). The mean age of the patients was 56,55 ± 10,59, the duration of the disease was 2,3 ± 1,2 years. All patients underwent a standard clinical examination, the following indices and scales were used to assess the activity of the underlying disease: VDI damage index, Bermingham systemic vasculitis activity scale (BVAS), RA activity scale (DAS 28-CRP). The functional state of the lungs was assessed using spirometry, bodipletismography, gas diffusion “single breath”. LUS was carried out for the evaluation of the location and number of B-lines on both right and left hemithoraces using commercially available echographic equipment with a 5-12 MHz linear transducer (Accuvix A30, Samsung Medison).Results:Most patients had an average number of B-lines 24,5[11,5;34,0]. Тhere were no significant differences in the number of В-lines between groups of patients of different nosologies. The total number of В-lines correlated with the index of activity of systemic vasculitis BVAS (р<0,05; r=0,83). There were no statistically significant correlations with clinical manifestations of pulmonary involvement.Conclusion:Lung ultrasound may be useful in screening secondary lung involvement in patients with rheumatic diseases with high activity.References:[1]Dietrich CF, Mathis G, Blaivas M, Volpicelli G, Seibel A, Wastl D, Atkinson NS, Cui XW, FanM, Yi D. Lung B-line artefacts and their use. J Thorac Dis 2016;8(6):1356-1365. doi: 10.21037/jtd.2016.04.55[2]Tatiana Barskova, Luna Gargani, Serena Guiducci, et al. Lung ultrasound for the screening of interstitial lung disease in very early systemic sclerosis Ann Rheum Dis 2013 72: 390-395 originally published online May 15 2012 doi: 10.1136/annrheumdis-2011-201072Disclosure of Interests:None declared
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Walker, A. M., B. C. Ritchie, T. M. Adamson et J. E. Maloney. « Effect of changing lung liquid volume on the pulmonary circulation of fetal lambs ». Journal of Applied Physiology 64, no 1 (1 janvier 1988) : 61–67. http://dx.doi.org/10.1152/jappl.1988.64.1.61.
Texte intégralRésumé :
During fetal life the lung develops as a liquid-filled structure with low blood flow compared with postnatal life. We studied the effects of liquid expansion of the fetal lung by measuring vascular conductance in perfused lungs in situ and arterial diameters in excised lungs of fetal lambs. Pulmonary vascular conductance invariably rose as the lung was deflated from its initial volume; maximal deflation to residual volume increased conductance 122%. With reexpansion, conductance fell progressively, culminating in cessation of flow at lung volumes of twice the initial volume. These changes persisted after vagotomy and thoracic sympathectomy and therefore were mechanical in character. Lung expansion from residual volume initially expanded 300- to 500-micron arteries but compressed arteries greater than 1,500 micron. Further expansion reduced the caliber of all arteries. Thus increasing lung liquid volume progressively constricts the pulmonary circulation in the fetus. Because the fetal pulmonary vascular resistance-lung volume relationship differs from that of the U-shaped form found in adult lungs, concepts based on the adult pulmonary circulation are not appropriate for liquid-filled fetal lungs.
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Mahfouzi, Seyed Hossein, Seyed Hamid Safiabadi Tali et Ghassem Amoabediny. « Decellularized human-sized pulmonary scaffolds for lung tissue engineering : a comprehensive review ». Regenerative Medicine 16, no 8 (août 2021) : 757–74. http://dx.doi.org/10.2217/rme-2020-0152.
Texte intégralRésumé :
The ultimate goal of lung bioengineering is to produce transplantable lungs for human beings. Therefore, large-scale studies are of high importance. In this paper, we review the investigations on decellularization and recellularization of human-sized lung scaffolds. First, studies that introduce new ways to enhance the decellularization of large-scale lungs are reviewed, followed by the investigations on the xenogeneic sources of lung scaffolds. Then, decellularization and recellularization of diseased lung scaffolds are discussed to assess their usefulness for tissue engineering applications. Next, the use of stem cells in recellularizing acellular lung scaffolds is reviewed, followed by the case studies on the transplantation of bioengineered lungs. Finally, the remaining challenges are discussed, and future directions are highlighted.
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Ahn, So Yoon, Dong Kyung Sung, Yun Sil Chang et Won Soon Park. « Intratracheal Transplantation of Mesenchymal Stem Cells Attenuates Hyperoxia-Induced Microbial Dysbiosis in the Lungs, Brain, and Gut in Newborn Rats ». International Journal of Molecular Sciences 23, no 12 (13 juin 2022) : 6601. http://dx.doi.org/10.3390/ijms23126601.
Texte intégralRésumé :
We attempted to determine whether intratracheal (IT) transplantation of mesenchymal stem cells (MSCs) could simultaneously attenuate hyperoxia-induced lung injuries and microbial dysbiosis of the lungs, brain, and gut in newborn rats. Newborn rats were exposed to hyperoxia (90% oxygen) for 14 days. Human umbilical cord blood-derived MSCs (5 × 105) were transplanted via the IT route on postnatal day (P) five. At P14, the lungs were harvested for histological, biochemical, and microbiome analyses. Bacterial 16S ribosomal RNA genes from the lungs, brain, and large intestine were amplified, pyrosequenced, and analyzed. IT transplantation of MSCs simultaneously attenuated hyperoxia-induced lung inflammation and the ensuing injuries, as well as the dysbiosis of the lungs, brain, and gut. In correlation analyses, lung interleukin-6 (IL-6) levels were significantly positively correlated with the abundance of Proteobacteria in the lungs, brain, and gut, and it was significantly inversely correlated with the abundance of Firmicutes in the gut and lungs and that of Bacteroidetes in the lungs. In conclusion, microbial dysbiosis in the lungs, brain, and gut does not cause but is caused by hyperoxic lung inflammation and ensuing injuries, and IT transplantation of MSCs attenuates dysbiosis in the lungs, brain, and gut, primarily by their anti-oxidative and anti-inflammatory effects.
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Yan, Xiao, Juan Jose Polo Carbayo, Ewald R. Weibel et Connie C. W. Hsia. « Variation of lung volume after fixation when measured by immersion or Cavalieri method ». American Journal of Physiology-Lung Cellular and Molecular Physiology 284, no 1 (1 janvier 2003) : L242—L245. http://dx.doi.org/10.1152/ajplung.00184.2002.
Texte intégralRésumé :
Organ volume is a critical parameter in morphometric analysis. The special problems of the lung as a nonsolid organ are overcome by tracheal instillation of fixatives at a constant airway pressure (Paw). Lung volume can change significantly after fixation as Paw change. To determine the variation of lung volume after fixation, we measured the volume of intact fixed lungs by serial immersion in saline (Vimm) at selected time points, compared with measurements obtained by point counting [Cavalieri Principle (Vcav)] after tissue sectioning to release Paw. Vimm was systematically higher than Vcav by 25% in dog lungs and 13% in guinea pig lungs ( P = 0.0003 between species). This size-dependent variability reflects residual elastic recoil, refolding and/or crumpling of alveolar septa after fixation. Vimm remained 14% higher than Vcav in dog lungs even after pressure release. Vcav/Vimmwas systematically lower in the upper than the lower strata of the same lung. We conclude that Vcav measured on lung slices after relaxation of Paw more precisely represents the state of the tissue to be used for subsequent morphometric analysis, particularly for large lungs.
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Jackson, R. M., C. F. Veal, C. B. Alexander, A. L. Brannen et J. D. Fulmer. « Neutrophils in reexpansion pulmonary edema ». Journal of Applied Physiology 65, no 1 (1 juillet 1988) : 228–34. http://dx.doi.org/10.1152/jappl.1988.65.1.228.
Texte intégralRésumé :
This study investigated the possible contribution of neutrophils to development of reexpansion pulmonary edema (RPE) in rabbits. Rabbits' right lungs were collapsed for 7 days and then reexpanded with negative intrathoracic pressure for 2 h before study, a model that creates unilateral edema in the reexpanded lungs but not in contralateral left lungs. Two hours after lung reexpansion, significant increases in lavage albumin concentration (17-fold), percent neutrophils (14-fold), and total number of neutrophils (7-fold) recovered occurred in the reexpanded lung but not in the left. After 2 h of reexpansion increased leukotriene B4 was detected in lavage supernatant from right lungs (335 +/- 33 pg/ml) compared with the left (110 +/- 12 pg/mg, P less than 0.01), and right lung lavage acid phosphatase activity similarly increased (6.67 +/- 0.35 U/l) compared with left (4.73 +/- 0.60 U/l, P less than 0.05). Neutropenia induced by nitrogen mustard (17 +/- 14 greater than neutrophils/microliters) did not prevent RPE, because reexpanded lungs from six neutropenic rabbits were edematous (wet-to-dry lung weight ratio 6.34 +/- 0.43) compared with their contralateral lungs (4.97 +/- 0.04, P less than 0.01). An elevated albumin concentration in reexpanded lung lavage from neutropenic rabbits (8-fold) confirmed an increase in permeability. Neutrophil depletion before reexpansion did not prevent unilateral edema, although neutrophils were absent from lung sections and alveolar lavage fluid from neutropenic rabbits.
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Chen, Jiawen, Ting Li, Chun Ye, Jiasheng Zhong, Jian-Dong Huang, Yiquan Ke et Haitao Sun. « The Lung Microbiome : A New Frontier for Lung and Brain Disease ». International Journal of Molecular Sciences 24, no 3 (21 janvier 2023) : 2170. http://dx.doi.org/10.3390/ijms24032170.
Texte intégralRésumé :
Due to the limitations of culture techniques, the lung in a healthy state is traditionally considered to be a sterile organ. With the development of non-culture-dependent techniques, the presence of low-biomass microbiomes in the lungs has been identified. The species of the lung microbiome are similar to those of the oral microbiome, suggesting that the microbiome is derived passively within the lungs from the oral cavity via micro-aspiration. Elimination, immigration, and relative growth within its communities all contribute to the composition of the lung microbiome. The lung microbiome is reportedly altered in many lung diseases that have not traditionally been considered infectious or microbial, and potential pathways of microbe–host crosstalk are emerging. Recent studies have shown that the lung microbiome also plays an important role in brain autoimmunity. There is a close relationship between the lungs and the brain, which can be called the lung–brain axis. However, the problem now is that it is not well understood how the lung microbiota plays a role in the disease—specifically, whether there is a causal connection between disease and the lung microbiome. The lung microbiome includes bacteria, archaea, fungi, protozoa, and viruses. However, fungi and viruses have not been fully studied compared to bacteria in the lungs. In this review, we mainly discuss the role of the lung microbiome in chronic lung diseases and, in particular, we summarize the recent progress of the lung microbiome in multiple sclerosis, as well as the lung–brain axis.
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Miyazaki, Hiroshi, V. Courtney Broaddus, Jeanine P. Wiener-Kronish, Teiji Sawa, Jean-Francois Pittet, Vladimir Kravchenko, John C. Mathison et al. « The Effects of Two Antiinflammatory Pretreatments on Bacterial-induced Lung Injury ». Anesthesiology 90, no 6 (1 juin 1999) : 1650–62. http://dx.doi.org/10.1097/00000542-199906000-00022.
Texte intégralRésumé :
Background Two antiinflammatory therapies that have been effective in preventing acid-induced lung injury were evaluated. Specifically, their effects on a subsequent bacterial-airspace challenge were compared. Bacteria were instilled 24 h after acid-induced lung injury. Pseudomonas aeruginosa PAO-1 was used as the bacteria, because its effects in healthy lungs was documented previously. Methods New Zealand white rabbits were anesthetized and three pretreatments were administered: (1) pentoxifylline pretreatment (a 20-mg/kg bolus dose and then 6 mg x kg(-1) x h(-1) given intravenously), (2) 1 ml anti-tumor necrosis factor alpha antiserum given intravenously, or (3) normal saline given intravenously. The pretreatment doses were shown previously to prevent acid-induced lung injury. Then 1.2 ml/kg hydrochloric acid (HCl), pH 1.25, was instilled into the rabbits' right lungs. All the animals underwent mechanical ventilation for 8 h. Twenty-four hours after the acid instillation, the rabbits were anesthetized again and 2 ml/kg (10(9) colony forming units/ml) PAO-1 was instilled into their left lungs. The rabbits' breathing was aided by mechanical ventilation for another 8 h, and then they were killed and exsanguinated. Results Both pretreatments attenuated the acid-induced lung injury of the noninstilled left lungs. Arterial oxygen tension and the lung edema of pretreated, acid-exposed animals were significantly and almost equally improved (compared with no pretreatments) by either of the pretreatments. However, when the bacteria were instilled into the left lungs 24 h after the acid injury, the pentoxifylline pretreatment but not the anti-tumor necrosis factor alpha pretreatment prevented much of the bacteria-induced lung injury. Pentoxifylline pretreatment significantly improved the measurements of left lung edema and epithelial and endothelial permeability. There was also a trend for improved oxygenation in the pentoxifylline-pretreated and infected animals. In contrast, the anti-tumor necrosis factor alpha pretreatment did not prevent the bacteria-induced lung injury and increased some of the measurements of lung injury. Conclusions Two antiinflammatory therapies that prevented acid-induced lung injury to the noninstilled left lungs had significantly different effects on a subsequent bacteria-induced lung injury to the left lungs. The therapies differed in their mechanism of tumor necrosis factor alpha blockade, and this may have affected the bacteria-induced injury to the lungs.
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Lindemer, Brian J., Robert D. Bongard, Raymond Hoffmann, Shelley Baumgardt, Frank J. Gonzalez et Marilyn P. Merker. « Genetic evidence for NAD(P)H:quinone oxidoreductase 1-catalyzed quinone reduction on passage through the mouse pulmonary circulation ». American Journal of Physiology-Lung Cellular and Molecular Physiology 300, no 5 (mai 2011) : L773—L780. http://dx.doi.org/10.1152/ajplung.00394.2010.
Texte intégralRésumé :
The quinones duroquinone (DQ) and coenzyme Q1 (CoQ1) and quinone reductase inhibitors have been used to identify reductases involved in quinone reduction on passage through the pulmonary circulation. In perfused rat lung, NAD(P)H:quinone oxidoreductase 1 (NQO1) was identified as the predominant DQ reductase and NQO1 and mitochondrial complex I as the CoQ1 reductases. Since inhibitors have nonspecific effects, the goal was to use Nqo1-null (NQO1−/−) mice to evaluate DQ as an NQO1 probe in the lung. Lung homogenate cytosol NQO1 activities were 97 ± 11, 54 ± 6, and 5 ± 1 (SE) nmol dichlorophenolindophenol reduced·min−1·mg protein−1 for NQO1+/+, NQO1+/−, and NQO1−/− lungs, respectively. Intact lung quinone reduction was evaluated by infusion of DQ (50 μM) or CoQ1 (60 μM) into the pulmonary arterial inflow of the isolated perfused lung and measurement of pulmonary venous effluent hydroquinone (DQH2 or CoQ1H2). DQH2 efflux rates for NQO1+/+, NQO1+/−, and NQO1−/− lungs were 0.65 ± 0.08, 0.45 ± 0.04, and 0.13 ± 0.05 (SE) μmol·min−1·g dry lung−1, respectively. DQ reduction in NQO1+/+ lungs was inhibited by 90 ± 4% with dicumarol; there was no inhibition in NQO1−/− lungs. There was no significant difference in CoQ1H2 efflux rates for NQO1+/+ and NQO1−/− lungs. Differences in DQ reduction were not due to differences in lung dry weights, wet-to-dry weight ratios, perfusion pressures, perfused surface areas, or total DQ recoveries. The data provide genetic evidence implicating DQ as a specific NQO1 probe in the perfused rodent lung.
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Xi, Jinxiang, Brendan Walfield, Xiuhua April Si et Alexander A. Bankier. « Lung Physiological Variations in COVID-19 Patients and Inhalation Therapy Development for Remodeled Lungs ». SciMedicine Journal 3, no 3 (1 septembre 2021) : 198–208. http://dx.doi.org/10.28991/scimedj-2021-0303-1.
Texte intégralRésumé :
In response to the unmet need for effective treatments for symptomatic patients, research efforts of inhaled therapy for COVID-19 patients have been pursued since the pandemic began. However, inhalation drug delivery to the lungs is sensitive to the lung anatomy and physiology, which can be significantly altered due to the viral infection. The ensued ventilation heterogeneity will change distribution and thus dosimetry of inhaled medications, rendering previous correlations concepts? of pulmonary drug delivery in healthy lungs less reliable. In this study, we first reviewed the recent developments of inhaled therapeutics and vaccines, as well as the latest knowledge of the lung structural variations documented by CT of COVID-19 patients' lungs. We then quantified the volume ratios of the poorly aerated lungs and non-aerated lungs in eight COVID-19 patients, which ranged 2-8% and 0.5-3%, respectively. The need to consider the diseased lung physiologies in estimating pulmonary delivery was emphasized. Diseased lung geometries with varying lesion sites and complexities were reconstructed using Statistical Shape Modeling (SSM). A new segmentation method was applied that could generate patient-specific lung geometries with an increased number of branching generations. The synergy of the CT-based lung segmentation and SSM-based airway variation showed promise for developing representative COVID-infected lung morphological models and investigating inhalation therapeutics in COVID-19 patients. Doi: 10.28991/SciMedJ-2021-0303-1 Full Text: PDF
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Mukhia, Rajeev, Dil Islam Mansur, Sidharth Timsina et Taneja BK. « Morphological and morphometrical studies of the human foetal lung ». Asian Journal of Medical Sciences 10, no 5 (11 août 2019) : 75–79. http://dx.doi.org/10.3126/ajms.v10i5.22136.
Texte intégralRésumé :
Background: Foetal lung is one of the organs of interest for researchers since a long time. Though, detailed study about adult lung is there in the literature but lungs at different stages in foetal period is less available.
Aims and Objective: To find out the morphological and morphometrical features of the foetal lung in different gestational weeks.
Materials and Methods: After ethical approval the study was carried out on 66 human foetal lungs aged between 16th to 40th gestational weeks in the Department of Anatomy, Manipal College of Medical Sciences. After the dissection of foetuses, the lungs were removed out and the presence of fissures and lobes for both lungs were noted. Weights of both lungs were calibrated by digital weighing machine. Dimensions of foetal lungs were recorded by vernier calliper. All the data were represented as mean then analyzed with MS excel 2007 software and represented graphically.
Results: In the normally developing foetuses the dimensions of both lung increases with increase in gestational age with more or less difference between the dimension of right and left lung. There was number of variations seen in the fissures and lobes of the lungs.
Conclusion: The fissures and lobes are needed for locating broncho-pulmonary segments hence, knowledge of their position is necessary both anatomically as well as clinically for planning lobectomies and surgical resections.
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McDonnell, T. J., J. Y. Westcott, J. Czartolomna et N. F. Voelkel. « Role of peptidoleukotrienes in hypoxic pulmonary vasoconstriction in rats ». American Journal of Physiology-Heart and Circulatory Physiology 259, no 3 (1 septembre 1990) : H751—H758. http://dx.doi.org/10.1152/ajpheart.1990.259.3.h751.
Texte intégralRésumé :
The role of leukotrienes in the mechanism of hypoxic pulmonary vasoconstriction (HPV) is controversial. To determine whether leukotriene C4 (LTC4) was produced during HPV, LTC4 levels were measured in individual samples of lung tissue, lung bronchoalveolar lavage fluid (BALF), and blood perfusate in isolated perfused lungs ventilated with normoxic or hypoxic gas mixtures. HPV was not associated with increased LTC4 in lung tissue or increased LTE4 in blood perfusate. Consistent with previous studies demonstrating elevated levels of LTC4 in pooled BALF fluid from hypoxic lungs, individual lung BALF samples demonstrated an elevation of LTC4 during hypoxia. However, the process of lung lavage alone stimulated eicosanoid production, with LTC4, 6-ketoprostaglandin F1 alpha, and thromboxane B2 levels being higher in lavaged compared to non-lavaged lungs. In lungs to which the lipoxygenase inhibitor AA 861 was added to the perfusate, a reduction in the lung tissue LTC4 levels was observed without any or only a slight reduction in HPV. To evaluate the physiological effects of LTC4 in the airways, exogenous LTC4 (1-1,000 ng) was added to the airways of both blood- and physiological salt solution-perfused lungs without any effect on the pulmonary artery pressure or a response to hypoxia. These results do not support the hypothesis that leukotrienes mediate HPV in the rat.
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Wyder, Michael A., Shannon M. Griffin, D. Nicole Worsham et Edna S. Kaneshiro. « Clearance In Vivo of Instilled [H]Cholesterol from the Rat Lung ». Biochemistry Research International 2010 (2010) : 1–4. http://dx.doi.org/10.1155/2010/965716.
Texte intégralRésumé :
Phospholipids and lung surfactant proteins are known to be recycled within the lung alveolus mainly by uptake into type II epithelial cells that secrete lipid-enriched lung surfactant. Dipalmitoyl phosphatidylcholine (DPPC) is the major component of lung surfactant lipids and cholesterol is the second most abundant. However, cholesterol turnover in vivo has not been measured and it is not known how long steroidal compounds persist in the lung in intact animals. Here we report on experiments in which radiolabeled cholesterol was instilled into the lungs of rats, then at various postinstillation periods, radioactive sterols in lavage fluid, and in postlavage whole lungs were measured in individual animals. Radioactive sterols in the lungs remained high for a week and were still detectable 46 days later. The clearance rate during the initial postinstillation week was approximately 10% per day. Both radioactive free and esterified sterols were recovered from bronchoalveolar lavage fluid and postlavage lungs.
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Moores, H. K., C. J. Beehler, M. E. Hanley, P. F. Shanley, E. E. Stevens, J. E. Repine et L. S. Terada. « Xanthine oxidase promotes neutrophil sequestration but not injury in hyperoxic lungs ». Journal of Applied Physiology 76, no 2 (1 février 1994) : 941–45. http://dx.doi.org/10.1152/jappl.1994.76.2.941.
Texte intégralRésumé :
Neutrophil accumulation in alveolar spaces is a conspicuous finding in hyperoxia-exposed lungs. We hypothesized that xanthine oxidase (XO)-derived oxidants contribute to retention of neutrophils in hyperoxic lungs. Rats were subjected to normobaric hyperoxia (100% O2) for 48 h, and lungs were assessed for neutrophil sequestration (morphometry and lavage cell counts) and injury (lavage albumin levels and lung weights). In rats exposed to hyperoxia, we found increased (P < 0.05) lung neutrophil retention, lavage albumin levels, and lung weights compared with normoxia-exposed control rats. Suppression of XO activity by pretreatment with allopurinol decreased (P < 0.05) lung neutrophil retention but increased (P < 0.05) lavage albumin concentrations and lung weights in hyperoxic rats. Allopurinol treatment had no effect (P > 0.05) on the numbers of macrophages or lymphocytes recoverable by lung lavage. Depletion of XO activity by an independent method, tungsten feeding, also decreased (P < 0.05) lung lavage neutrophil counts and increased (P < 0.05) lavage albumin concentrations. We conclude that XO may be involved in lung neutrophil retention but not lung injury during exposure to hyperoxia.
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Harding, R., et S. B. Hooper. « Regulation of lung expansion and lung growth before birth ». Journal of Applied Physiology 81, no 1 (1 juillet 1996) : 209–24. http://dx.doi.org/10.1152/jappl.1996.81.1.209.
Texte intégralRésumé :
Fetal lung growth depends on the degree to which lungs are distended with luminal liquid. Fetal lungs are highly distended such that mean luminal volume exceeds the static relaxation volume. This high level of expansion is maintained by fetal breathing movements and by resistive effects of the upper airway during apnea; both factors oppose lung recoil. Mechanical stress in lung and other tissues stimulates cell division and tissue remodeling. Potential transduction mechanisms involve direct effects of cellular tension and mediation of locally released mitogenic factors. Further studies are required to further define links between lung tissue stress, increased growth, structural remodeling, and the endocrine environment. A common cause of fetal lung hypoplasia is a sustained reduction in mean lung expansion. Studies of mechanisms controlling fetal lung expansion have led to insights into the etiology of fetal lung hypoplasia and how it may be remedied in utero. Fetal lung hypoplasia can have long-lasting effects on postnatal lung function, as airway and alveolar formation may be compromised. Preterm birth may also result in incomplete structural development of the lungs as it shortens the period of increased intrauterine lung expansion.
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Pearse, D. B., et J. T. Sylvester. « Spontaneous injury in isolated sheep lungs : role of resident polymorphonuclear leukocytes ». Journal of Applied Physiology 72, no 6 (1 juin 1992) : 2475–81. http://dx.doi.org/10.1152/jappl.1992.72.6.2475.
Texte intégralRésumé :
Perfusion of isolated sheep lungs with homologous blood caused pulmonary hypertension and edema that was not altered by depletion of perfusate polymorphonuclear (PMN) leukocytes (D. B. Pearse et al., J. Appl. Physiol. 66: 1287–1296, 1989). The purpose of this study was to evaluate the role of resident PMN leukocytes in this injury. First, we quantified the content and activation of lung PMN leukocytes before and during perfusion of eight isolated sheep lungs with a constant flow (100 ml.kg-1.min-1) of homologous blood. From measurements of myeloperoxidase (MPO) activity, we estimated that the lungs contained 1.2 x 10(10) PMN leukocytes, which explained why the lung PMN leukocyte content, measured by MPO activity and histological techniques, did not increase significantly with perfusion, despite complete sequestration of 2.0 x 10(9) PMN leukocytes from the perfusate. MPO activities in perfusate and lymph supernatants did not increase during perfusion, suggesting that lung PMN leukocytes were not activated. Second, we perfused lungs from 6 mechlorethamine-treated and 6 hydroxyurea-treated sheep with homologous leukopenic blood and compared them with 11 normal lungs perfused similarly. Despite marked reductions in lung PMN leukocyte concentration, there were no differences in pulmonary arterial pressure, lymph flow, or reservoir weight between groups. Extravascular lung water was greater in both groups of leukopenic lungs. These results suggest that resident PMN leukocytes did not contribute to lung injury in this model.
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Bourn, Sebastian, T. E Scott et E. J Hulse. « A comparison of CT lung voxel density analysis in a blast and non blast injured casualty. » Journal of the Royal Army Medical Corps 165, no 3 (3 octobre 2018) : 166–68. http://dx.doi.org/10.1136/jramc-2018-000979.
Texte intégralRésumé :
IntroductionPrimary blast lung injury (PBLI) is a prominent feature in casualties following exposure to blast. PBLI carries high morbidity and mortality, but remains difficult to diagnose and quantify. Radiographic diagnosis of PBLI was historically made with the aid of plain radiographs; more recently, qualitative review of CT images has assisted diagnosis.MethodsWe report a novel way of measuring post-traumatic acute lung injury using CT lung density analysis in two casualties. One casualty presented following blast exposure with confirmed blast lung injury and the other presented following extremity injury without blast exposure. Three-dimensional lung maps of each casualty were produced from their original trauma CT scan. Analysis of the lung maps allowed quantitative radiological comparison exposing areas of reduced aeration of the patient’s lungs.Results45% of the blast-exposed lungs were non-aerated compared with 10% in the non-blast-exposed lungs.DiscussionIn these example cases quantitative CT lung density analysis allowed blast-injured lungs to be distinguished from non-blast-exposed lungs.
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Krieger, B. P., W. H. Loomis, G. T. Czer et R. G. Spragg. « Mechanisms of interaction between oxygen and granulocytes in hyperoxic lung injury ». Journal of Applied Physiology 58, no 4 (1 avril 1985) : 1326–30. http://dx.doi.org/10.1152/jappl.1985.58.4.1326.
Texte intégralRésumé :
Hyperoxia and infused granulocytes act synergistically in producing a nonhydrostatic high-permeability lung edema in the isolated perfused rabbit lung within 4 h, which is substantially greater than that seen with hyperoxia alone. We hypothesized that the interaction between hyperoxia and granulocytes was principally due to a direct effect of hyperoxia on the lung itself. Isolated perfused rabbit lungs that were preexposed to 2 h of hyperoxia (95% O2–5% CO2) prior to the infusion of unstimulated granulocytes (under normoxic conditions) developed significant nonhydrostatic lung edema (P = 0.008) within 2 h when compared with lungs that were preexposed to normoxia (15% O2–5% CO2) prior to granulocyte perfusion. The edema in the hyperoxic-preexposed lungs was accompanied by significant increases in bronchoalveolar lavage (BAL) protein, BAL granulocytes, BAL thromboxane and prostacyclin levels, perfusate chemotactic activity, and lung lipid peroxidation. These findings suggest that the synergistic interaction between hyperoxia and granulocytes in producing acute lung injury involves a primary effect of hyperoxia on the lung itself.
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Tetenev, K. F., F. F. Tetenev, T. S. Ageyeva, T. N. Bodrova, A. I. Karzilov et P. Ye Mesko. « MECHANISMS OF COUNTERACTING FLAP-VALVE BRONCHIAL OBSTRUCTION IN CASE OF OBSTRUCTIVE PULMONARY EMPHYSEMA ». Bulletin of Siberian Medicine 14, no 4 (28 août 2015) : 75–81. http://dx.doi.org/10.20538/1682-0363-2015-4-75-81.
Texte intégralRésumé :
The research goal was to formulate and substantiate the hypothesis explaining support for an expiratory air flow in case of pulmonary emphysema. The research method consisted in comparing the mechanical properties of lungs in practically healthy individuals (37 individuals, mean age – (30.4 ± 1.7) y.o.) and COPD patients with pronounced lung emphysema (30 patients, mean age – (52.1 ± 2.3) y.o.) as well as those of isolated normal lungs (n = 14) and isolated lungs of patients who died of COPD (n = 5). Pulmo-nary mechanics was studied via the simultaneous measurement of transpulmonary pressure and lung ven-tilation volume. General lung hysteresis and elastic lung hysteresis were calculated. The mechanical properties of isolated lungs were studied using passive ventilation under the Donders bell. The air flow was interrupted in order to measure alveolar pressure and develop an elastic lung hysteresis curve. Pres-sure in the Donders bell was changed by means of a special pump in automatic and manual modes. The research has not revealed any fundamental differences between the mechanical properties of the normal and emphysematous lungs. A minimum increase in the pressure inside the Donders bell over atmospheric pressure used to stop air ejection in both normal and the emphysematous lungs as the result of flap-valve bronchial obstruction. In living beings, air is ejected from lungs with an increase in pressure under the conditions of forced expiration. Pressure increases up to (38.6 ± 2.71) cm H2O in healthy individuals and up to (20.5 ± 1.86) cm H2O in COPD patients. Probably, an expiratory air flow is supported by active expiratory bronchial dilatation that counteracts flap-valve bronchial obstruction. The hypothesis is based on the confirmed ability of the lungs to perform inspiratory actions (in addition to the action of respiratory muscles) and the theory of mechanical lung activity.