The authors demonstrate that the conditions for correct flow measurement are not fulfilled when a resistive flow transducer (Fleisch pneumotachograph, screen pneumotachograph etc.) is connected directly to the mouth or to the end of the endotracheal tube. This is because the composition, temperature and water content of the respiratory gas varies markedly within a respiratory cycle, the mechanically ventilated patient exhales with a huge expiratory initial peak flow, and laminar flow tends to switch over to turbulent flow in this system. Methods are proposed of continuously compensating the effects of changing gas composition, reducing expiratory peak flow without an increase in expiratory resistance, and preventing the occurrence of turbulent flow. The improvement of measuring accuracy to 2% makes the estimation of respiratory volumes more reliable. Secondly, the increased quality of primary data enables one to analyze these data in a more complex and sophisticated manner (N2-washout compartment analyses, VDS, investigation of complicated modes of ventilation such as IMV, etc.).
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Innate Immun
January 2025
Department of Respiratory and Critical Medicine, the First Affiliated Hospital of Soochow University, Suzhou, China.
The application of biological therapy and glucocorticoids in Auto-immune diseases (AID) patients will cause immunocompromised host (ICH) prone to infection. And monocytes play a key role in both innate and adaptive immune responses. We aimed to investigate the changes of circulating monocyte subsets in AID or AID-ICH patients with pulmonary infection.
View Article and Find Full Text PDFActa Radiol
January 2025
Department of Radiology & Institute of Rehabilitation and Development of Brain Function, Nanchong Central Hospital, The Second Clinical Medical College of North Sichuan Medical College, Nanchong, Sichuan, PR China.
Hyperperfusion is related to vessel recanalization, tissue reperfusion, and collateral circulation. To determine the prognostic impact of hyperperfusion after an acute ischemic stroke (AIS) identified by arterial spin labeling (ASL) cerebral blood flow. Studies published in PubMed, Embase, and Cochrane Library databases were searched.
View Article and Find Full Text PDFCirc Res
January 2025
Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario, Canada (C.P., S.A., J.W.A., R.L., F.N., J.S., I.C.).
Background: Iron is an essential micronutrient for cell survival and growth; however, excess of this metal drives ferroptosis. Although maternal iron imbalance and placental hypoxia are independent contributors to the pathogenesis of preeclampsia, a hypertensive disorder of pregnancy, the mechanisms by which their interaction impinge on maternal and placental health remain elusive.
Methods: We used placentae from normotensive and preeclampsia pregnancy cohorts, human H9 embryonic stem cells differentiated into cytotrophoblast-like cells, and placenta-specific preeclamptic mice.
Arterioscler Thromb Vasc Biol
January 2025
Metabolic and Immune Diseases Department, Biomedical Research Institute Sols-Morreale (IIBM), National Research Council (CSIC), Autonoma University of Madrid, Spain (T.A.-G., S.M.-T., R.C.-M., S.U.-B., S.M.-P.).
Background: Hypoxia is associated with the onset of cardiovascular diseases including cardiac hypertrophy and pulmonary hypertension. HIF2 (hypoxia-inducible factor 2) signaling in the endothelium mediates pulmonary arterial remodeling and subsequent elevation of the right ventricular systolic pressure during chronic hypoxia. Thus, novel therapeutic opportunities for pulmonary hypertension based on specific HIF2 inhibitors have been proposed.
View Article and Find Full Text PDFJ Cereb Blood Flow Metab
January 2025
A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland.
Zero echo time (zero-TE) pulse sequences provide a quiet and artifact-free alternative to conventional functional magnetic resonance imaging (fMRI) pulse sequences. The fast readouts (<1 ms) utilized in zero-TE fMRI produce an image contrast with negligible contributions from blood oxygenation level-dependent (BOLD) mechanisms, yet the zero-TE contrast is highly sensitive to brain function. However, the precise relationship between the zero-TE contrast and neuronal activity has not been determined.
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