Artigos de revistas: "Clse"

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Khan, Jamal N., Timothy Griffiths, Tamseel Fatima, Leah Michael, Andreea Mihai, Zeeshan Mustafa, Kully Sandhu, Robert Butler, Simon Duckett e Grant Heatlie. "Feasibility of physiologist-led stress echocardiography for the assessment of coronary artery disease". Echo Research and Practice 4, n.º 2 (junho de 2017): 29–36. http://dx.doi.org/10.1530/erp-17-0019.

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Background Physiologist-led stress echocardiography (PLSE) services provide potential for expansion of SE services and increased productivity for cardiologists. There are however no published data on the feasibility of PLSE. We sought to assess the feasibility, safety and robustness of PLSE and cardiologist-led stress echocardiography (CLSE) for coronary artery disease (CAD) assessment. Methods Retrospective analysis of 898 patients undergoing PLSE or CLSE for CAD assessment using exercise or dobutamine stress over 24 months. PLSE involved 2 cardiac physiologists (exercise) or 1 physiologist plus 1 cardiac nurse (dobutamine). A cardiology registrar was present in the echocardiography department during PLSE in case of medical complications. CLSE involved 1 physiologist and 1 trainee cardiologist who analysed the study and reviewed findings with an imaging cardiologist. Sixteen-segment wall motion scoring (WMS, WMSI) analysis was performed. Feasibility (stressor, image quality, proportion of completed studies, agreement with imaging cardiologist analysis) and safety (complication rate) were compared for PLSE and CLSE. Results The majority of studies were CLSE (56.2%) and used dobutamine (68.7%). PLSE more commonly used exercise (69.2%). Overall, 96% of studies were successfully completed (>14 diagnostic segments in 98%, P = 0.899 PLSE vs CLSE). Commencement of PLSE was associated with an increase in annual SE’s performed for CAD assessment. Complication rates were comparably very low for PLSE and CLSE (0.8% vs 1.8%, P = 0.187). There was excellent agreement between PLSE and CLSE WMS interpretation of 480 myocardial segments at rest (κ = 0.87) and stress (κ = 0.70) and WMSI (ICCs and Pearson’s r >0.90, zero Bland–Altman mean bias). Conclusion This to our knowledge is the first study of the feasibility of PLSE. PLSE performed by well-trained physiologists is feasible and safe in contemporary practice. PLSE and CLSE interpretation of stress echocardiography for CAD agree very closely.

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Gunther, A., M. Kalinowski, A. Elssner e W. Seeger. "Clot-embedded natural surfactant: kinetics of fibrinolysis and surface activity". American Journal of Physiology-Lung Cellular and Molecular Physiology 267, n.º 5 (1 de novembro de 1994): L618—L624. http://dx.doi.org/10.1152/ajplung.1994.267.5.l618.

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Polymerization of fibrin in the presence of pulmonary surfactant was recently noted to induce incorporation of phospholipids into the insoluble clot material, thereby effecting severe loss of surface activity (W. Seeger, A. Elssner, A. Gunther, H.-J. Kramer, and H. O. Kalinowski. Am. J. Respir. Cell Mol. Biol. 9: 213'220, 1993). In the present study, we investigated the influence of such incorporation of calf lung surfactant extract (CLSE) on the enzymatic cleavage of the fibrin network with the use of plasmin, trypsin, or elastase. Employing a fibrin-plate assay, the proteolytic release of radioactivity originating from 125I-labeled fibrinogen was assessed, and the pattern of split products was characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis technique. Surface activity of CLSE was measured in the pulsating bubble surfactometer. When incorporated into the fibrin clot, CLSE inhibited the cleavage of fibrin by all proteases in a dose-dependent manner without affecting the profile of scission products. Inhibition of plasmin-induced clot lysis was also noted on incorporation of CLSE into clotted plasma and on incorporation of dipalmitoylphosphatidylcholine into fibrin polymers. In contrast, corresponding concentrations of CLSE added to the incubation medium after preformation of the fibrin matrix did not substantially influence the kinetics of fibrinolysis. CLSE incorporation into the nascent fibrin clot resulted in complete loss of surface activity, but adsorption and surface tension-lowering properties were largely restored by subsequent plasmic clot lysis. Arising fibrin split products were shown to display similar inhibitory strength on CLSE surface activity compared with fibrinogen split products.(ABSTRACT TRUNCATED AT 250 WORDS

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Engstrom, P. C., B. A. Holm e S. Matalon. "Surfactant replacement attenuates the increase in alveolar permeability in hyperoxia". Journal of Applied Physiology 67, n.º 2 (1 de agosto de 1989): 688–93. http://dx.doi.org/10.1152/jappl.1989.67.2.688.

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Rabbits exposed to hyperoxia develop surfactant deficiency, abnormal lung mechanics, and increased permeability to solute. We investigated whether replenishment of depleted alveolar surfactant by the intratracheal instillation of calf lung surfactant extract (CLSE) would mitigate the increase in alveolar permeability to solute. Twenty-eight rabbits were exposed to 100% O2 for 72 h and received intratracheal instillations of 125 mg CLSE (approximately 170 mumol dipalmitoyl phosphatidylcholine) at 24 and 48 h. The interlobar and intralobar distribution of CLSE was quantified by adding [14C]dipalmitoyl phosphatidylcholine liposes into the instillate and measuring the levels of activity in lung tissue. CLSE was nonuniformly distributed in the different lung lobes, the right lower lobe receiving more CLSE than the rest. Alveolar epithelial permeability to solute was assessed by instilling 10 ml isotonic saline, which contained a trace amount of [57Co]cyanocobalamin, in the right lower lobe and measuring the disappearance of the tracer from the alveolar saline and its appearance in the arterial blood during a 1-h period. CLSE treatment was associated with significantly increased 72-h survival in hyperoxia compared with saline-treated controls (number of survivors: 16/17 vs. 5/11, P less than 0.01). CLSE treatment significantly reduced the rate constant for the movement of cyanocobalamin out of the alveolar space (24 +/- 5 vs. 42 +/- 6 min-1 x 10(-3), P less than 0.01) and tracer appearance in the blood at the end of the study (7 +/- 1 vs. 34 +/- 13%, P less than 0.01) when compared with values in saline controls.(ABSTRACT TRUNCATED AT 250 WORDS)

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Kumar, Sandeep, Karuna Gautam, Anima Tripathi e Poonam Singh. "Antidepressant-like effects of seeds of Citrullus lanatus in the reserpine-induced depressed mouse model". Brazilian Journal of Development 10, n.º 7 (30 de julho de 2024): e71569. http://dx.doi.org/10.34117/bjdv10n7-060.

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Depression is a mental health disorder that affects millions of people worldwide. Plants and their products are widely used in the treatments of various diseases including depression for their therapeutic effectiveness with least or no side effects. The present study has therefore been conducted to evaluate the antidepressant like effects of Citrullus lanatus seed extract (CLSE) in the reserpine-induced depressed mouse model by assessing the phytoconstituents of CLSE, body weight, behaviour, histopathology of the adrenal gland and level of plasma corticosterone. Twenty-four adult male mice of Swiss strain were distributed into four groups of six each (n=6). Group I served as control while groups II, III and IV received reserpine (RES: 0.75mg/kg/BW/day) for 14 days, CLSE (300mg/kg/BW/day) only, for 28 days, and RES+CLSE [RES treatment for 14 days followed by CLSE treatment for 28 days], respectively. Behavioural alterations were analysed by food consumption, sucrose preference, eight-arm radial maze, and forced swim tests during the treatment. RES-induced depression caused marked alterations in the body weight, all behavioural parameters, histopathology of the adrenal cortex, and in the level of plasma corticosterone, compared with the control. Administration of CLSE only, did not cause significant alterations in all the studied parameters, compared with the control. However, CLSE administration in RES-treated mice resulted in significant restoration in all the studied parameters, similar to the control. The findings therefore suggest the antidepressive activity of the seeds of C. lanatus, that may emerge as one of the potential sources among the natural therapies of depression disorder.

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Loewen, G. M., B. A. Holm, L. Milanowski, L. M. Wild, R. H. Notter e S. Matalon. "Alveolar hyperoxic injury in rabbits receiving exogenous surfactant". Journal of Applied Physiology 66, n.º 3 (1 de março de 1989): 1087–92. http://dx.doi.org/10.1152/jappl.1989.66.3.1087.

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We have previously demonstrated that instillation of a calf lung surfactant extract (CLSE) in rabbits after exposure to 100% O2 for 64 h mitigates the progression of lung pathology after return to room air (J. Appl. Physiol. 62: 756–761, 1987). In the present study, we investigated whether we could prevent or reduce the onset and development of hyperoxic lung injury by sequential instillations of CLSE during the hyperoxic exposure. Rabbits were exposed to 100% O2. CLSE (125 mg, approximately 170 mumol of phospholipid) was suspended in 10 ml of sterile saline and instilled intratracheally into their lungs, starting at 24 h in O2, a time at which no physiological or biochemical injury was detected, and at 24-h intervals thereafter. Control rabbits breathed 100% O2 and received either equal volumes of saline or no instillations at all. CLSE-instilled rabbits had higher arterial PO2 (Pao2) values throughout the exposure period and survived longer when compared with saline controls [120 +/- 4 vs. 102 +/- 4 (SE) h; n greater than or equal to 10; P less than 0.05]. At 72 h in O2, CLSE-instilled rabbits had significantly higher lavageable alveolar phospholipid levels (12.5 +/- 1.5 vs. 5 +/- 1 mumol/kg) and total lung capacities (41 +/- 2 vs. 25 +/- 3.5 ml/kg) and lower levels of alveolar protein (24 +/- 3 vs. 52 +/- 8 mg/kg), minimum surface tension (2 +/- 1 vs. 26.1 dyn/cm), and lung wet-to-dry weights (5.9 +/- 0.2 vs. 6.5 +/- 0.3). After 72 h in O2, lungs from both CLSE- and saline-instilled rabbits showed evidence of diffuse hyperoxic injury. However, atelectasis was less prominent in the former. We concluded that instillation of CLSE limits the onset and development of hyperoxic lung injury to the alveolar epithelium of rabbits.

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Wang, Z., A. L. Schwan, L. L. Lairson, J. S. O'Donnell, G. F. Byrne, A. Foye, B. A. Holm e R. H. Notter. "Surface activity of a synthetic lung surfactant containing a phospholipase-resistant phosphonolipid analog of dipalmitoyl phosphatidylcholine". American Journal of Physiology-Lung Cellular and Molecular Physiology 285, n.º 3 (setembro de 2003): L550—L559. http://dx.doi.org/10.1152/ajplung.00346.2002.

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Surface activity and sensitivity to inhibition from phospholipase A2 (PLA2), lysophosphatidylcholine (LPC), and serum albumin were studied for a synthetic C16:0 diether phosphonolipid (DEPN-8) combined with 1.5% by weight of mixed hydrophobic surfactant proteins (SP)-B/C purified from calf lung surfactant extract (CLSE). Pure DEPN-8 had better adsorption and film respreading than the major lung surfactant phospholipid dipalmitoyl phosphatidylcholine and reached minimum surface tensions <1 mN/m under dynamic compression on the Wilhelmy balance and on a pulsating bubble surfactometer (37°C, 20 cycles/min, 50% area compression). DEPN-8 + 1.5% SP-B/C exhibited even greater adsorption and had overall dynamic surface tension lowering equal to CLSE on the bubble. In addition, films of DEPN-8 + 1.5% SP-B/C on the Wilhelmy balance had better respreading than CLSE after seven (but not two) cycles of compression-expansion at 23°C. DEPN-8 is structurally resistant to degradation by PLA2, and DEPN-8 + 1.5% SP-B/C maintained high adsorption and dynamic surface activity in the presence of this enzyme. Incubation of CLSE with PLA2 led to chemical degradation, generation of LPC, and reduced surface activity. DEPN-8 + 1.5% SP-B/C was also more resistant than CLSE to direct biophysical inhibition by LPC, and the two were similar in their sensitivity to biophysical inhibition by serum albumin. These findings indicate that synthetic surfactants containing DEPN-8 combined with surfactant proteins or related synthetic peptides have potential utility for treating surfactant dysfunction in inflammatory lung injury.

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Yan, Wenfei, Samares C. Biswas, Ted G. Laderas e Stephen B. Hall. "The melting of pulmonary surfactant monolayers". Journal of Applied Physiology 102, n.º 5 (maio de 2007): 1739–45. http://dx.doi.org/10.1152/japplphysiol.00948.2006.

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Monomolecular films of phospholipids in the liquid-expanded (LE) phase after supercompression to high surface pressures (π), well above the equilibrium surface pressure (πe) at which fluid films collapse from the interface to form a three-dimensional bulk phase, and in the tilted-condensed (TC) phase both replicate the resistance to collapse that is characteristic of alveolar films in the lungs. To provide the basis for determining which film is present in the alveolus, we measured the melting characteristics of monolayers containing TC dipalmitoyl phosphatidylcholine (DPPC), as well as supercompressed 1-palmitoyl-2-oleoyl phosphatidylcholine and calf lung surfactant extract (CLSE). Films generated by appropriate manipulations on a captive bubble were heated from ≤27°C to ≥60°C at different constant π above πe. DPPC showed the abrupt expansion expected for the TC-LE phase transition, followed by the contraction produced by collapse. Supercompressed CLSE showed no evidence of the TC-LE expansion, arguing that supercompression did not simply convert the mixed lipid film to TC DPPC. For both DPPC and CLSE, the melting point, taken as the temperature at which collapse began, increased at higher π, in contrast to 1-palmitoyl-2-oleoyl phosphatidylcholine, for which higher π produced collapse at lower temperatures. For π between 50 and 65 mN/m, DPPC melted at 48–55°C, well above the main transition for bilayers at 41°C. At each π, CLSE melted at temperatures >10°C lower. The distinct melting points for TC DPPC and supercompressed CLSE provide the basis by which the nature of the alveolar film might be determined from the temperature-dependence of pulmonary mechanics.

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Xuan, Zhi Wu, e Kai Nie. "Constrained Least Square Estimation Algorithm for Multisensor Bearings-Only Passive Target Tracking". Applied Mechanics and Materials 602-605 (agosto de 2014): 1842–46. http://dx.doi.org/10.4028/www.scientific.net/amm.602-605.1842.

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The sensor needs to maneuver to get better observability in Bearings-Only passive target tracking with single sensor which makes the observation time longer. Multisensor Bearings-Only passive target tracking can solve the problem using exchange data. So the constrained Least Square Estimation (CLSE) algorithm is proposed for Multisensor Bearings-Only passive target tracking. The constrained condition is introduced to the Least Square Estimation algorithm firstly. Then the eigenvector corresponding to the least eigenvalue of the matrix is used to overcome the shortcoming of Extend Kalman Filter algorithm which needs the initial value. Also the bias problem of Least Square Estimation is conquered. The simulation results show that the CLSE can gradually approach the Cramer-Rao Lower Bound and its precision is better than the Least Square Estimation algorithm. Finally the CLSE is proved to be a gradually, stable and almost unbiased estimation algorithm.

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Levartovsky, Shifra, Benny Ferdman, Nahawand Safadi, Tujan Hanna, Eran Dolev e Raphael Pilo. "Effect of Silica-Modified Aluminum Oxide Abrasion on Adhesion to Dentin, Using Total-Etch and Self-Etch Systems". Polymers 15, n.º 2 (14 de janeiro de 2023): 446. http://dx.doi.org/10.3390/polym15020446.

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This study compared the shear bond strength (SBS) and micromorphology of composite resin to human dentin after pre-treatment with silica-modified aluminum oxide air abrasion. Forty-six molar teeth were treated with either Scotchbond Multi-Purpose (SCMP) or Clearfil SE Bond (CLSE) adhesive. Buccal surfaces were pre-treated with the CoJet air abrasion system (SB), and lingual surfaces were controls. The adhesion of light-cured resin composite to the treated dentin surface was evaluated with SBS. After debonding, substrate surfaces were examined with an optical microscope for failure analysis. In addition, 15 molar teeth were sectioned and randomly assigned to one of five groups, according to the dentin surface pre-treatment and adhesive type, and examined with high-vacuum scanning electron microscopy/energy dispersive X-rays (SEM/EDS). The type of adhesive had a significant effect on SBS (p = 0.000); CLSE had the highest values. SB did not affect SBS (p = 0.090). SEM/EDS revealed residual aluminum and/or silicon on all dentin surfaces after SB, except for the control. Treatment with 32% phosphoric acid in the SCMP adhesive decreased the amounts of aluminum and silicon compared to SB dentin only, whereas CLSE resulted in similar quantities of aluminum and silicon as air-abraded dentin. The results of this study indicate that CLSE might have a higher bond strength to dentin than SCMP. Pre-treatment with SB does not appear to affect bonding strength.

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Haddad, I. Y., B. A. Holm, L. Hlavaty e S. Matalon. "Dependence of surfactant function on extracellular pH: mechanisms and modifications". Journal of Applied Physiology 76, n.º 2 (1 de fevereiro de 1994): 657–62. http://dx.doi.org/10.1152/jappl.1994.76.2.657.

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We investigated alterations in pH on the surface properties of natural lung surfactant and the calf lung surfactant extract (CLSE), suspended in 10 mM N-2-hydroxyethylpiperazine-N′-2-ethanesulfonic acid, using a pulsating bubble surfactometer. Increasing the pH value of the medium to > 7.4 decreased the ability of CLSE, but not of natural lung surfactant mixtures (2 mg phospholipid/ml), to achieve a low minimum surface tension during dynamic compression and enhanced their sensitivity to albumin inactivation. These detrimental effects on surface tension were reversed by addition of surfactant protein A (SP-A; 3% by weight) or by increasing the lipid concentration to 4 mg/ml. SP-A-induced lipid aggregation at pH 10 was not different than at pH 7.4. Alkalinization impaired the ability of CLSE to restore normal lung mechanics in excised surfactant-deficient rats lungs. These results indicate that cooperation between SP-A and the hydrophobic surfactant proteins has an important role in achieving low minimum surface tension at pH > or = 7.6.

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Dorokhov, Aleksandr, e Nadezhda Vladimirovna Pakhomova. "Fundamentals of theoretical and applied aspects of functioning of collective life saving equipment of sea going ship crews". Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies 2020, n.º 3 (19 de agosto de 2020): 7–15. http://dx.doi.org/10.24143/2073-1574-2020-3-7-15.

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The article presents the substantiation of efficiency of sea transport in the world transport system. The main condition of ensuring water safety is equipment of ships with fail-safe and effective collective life-saving equipment (CLSE). Today the standard rescue operation when using CLSE is a series-parallel action of the ship’s crew, where the ship is sinking on an even keel, or with a slight roll to one side. It has been stated that such cases are extremely rare. As a rule, the situation develops rapidly. Accident statistics disposes to developing the modern approaches to the safety of human life at sea. There are two directions for safety ensuring. One of them is the development and implementation of artificial intelligence systems for CLSE, when CLSE independently, without human control, responds to the emergency with greater probability of the ship loss and the crew death. Another direction is when there is no need to save the crew (in case of unmanned ships). There are considered the Russian diesel engines for the lifeboats: specialized marine diesels 4CHSP9.5/11 - Caspiy 30M and 4CHSP9.5/11 - Caspiy 40. Both engines are equipped with a dual start-up system - manual and electric starter, they have a reverse gear transmission, a single-circuit flow-through sea water cooling system, decompression devices and standard mounted units, ac-cording to the requirements of the International Convention of Saving Life at Sea (SOLAS) and the International Code of Life-Saving Appliances (LSA Code). In modern environment, the scientific foundations and technical solutions are being developed to ensure the reliable start-up of swirl-chamber diesel engines by exposing the fuel to physical fields, without using glow plugs

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Holm, B. A., e R. H. Notter. "Effects of hemoglobin and cell membrane lipids on pulmonary surfactant activity". Journal of Applied Physiology 63, n.º 4 (1 de outubro de 1987): 1434–42. http://dx.doi.org/10.1152/jappl.1987.63.4.1434.

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These experiments characterize the effects of hemoglobin and erythrocyte membrane lipids on the dynamic surface activity and adsorption facility of whole lung surfactant (LS) and a calf lung surfactant extract (CLSE) used clinically in surfactant replacement therapy for the neonatal respiratory distress syndrome (RDS). The results show that, at concentrations from 25 to 200 mg/ml, hemoglobin (Hb) increased the minimum dynamic surface tension of LS or CLSE mixtures (0.5 and 1.0 mumol/ml) from less than 1 to 25 dyn/cm on an oscillating bubble apparatus at 37 degrees C. Similarly, erythrocyte membrane lipids (0.5–3 mumol/ml) also prevented LS and CLSE suspensions (0.5–2.0 mumol/ml) from lowering surface tension below 19 dyn/cm under dynamic compression on the bubble. Surface pressure-time adsorption isotherms for LS suspensions (0.084 and 0.168 mumol phospholipid/ml) were also adversely affected by Hb (0.3–2.5 mg/ml), having a slower adsorption rate and magnitude. Significantly, these inhibitory effects of Hb and membrane lipids could be abolished if LS and CLSE concentrations were raised to high levels. In complementary physiological experiments, instillation of Hb, membrane lipids, or albumin into excised rat lungs was shown to cause a decrease in pressure-volume compliance. This decreased compliance was most prominent in lungs made partially surfactant deficient before inhibitor delivery and could be reversed by supplementation with active exogenous surfactant. Taken together, these data show that molecular components in hemorrhagic pulmonary edema can biophysically inactivate endogenous LS and adversely affect lung mechanics. Moreover, exogenous surfactant replacement can reverse this process even in the continued presence of inhibitor molecules and thus has potential utility in therapy for adult as well as neonatal RDS.

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Seeger, W., C. Grube, A. Gunther e R. Schmidt. "Surfactant inhibition by plasma proteins: differential sensitivity of various surfactant preparations". European Respiratory Journal 6, n.º 7 (1 de julho de 1993): 971–77. http://dx.doi.org/10.1183/09031936.93.06070971.

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Leakage of plasma proteins into the alveolar space may inhibit surfactant function. We compared the surface properties and the sensitivity to inhibitory proteins of different organic solvent surfactant extracts and a synthetic surfactant. Experiments were performed in the pulsating bubble surfactometer, with surfactant concentrations ranging between 0.1 and 2 mg.ml-1. Inhibition profiles towards fibrinogen, albumin and haemoglobin were obtained from calf lung surfactant extracts (CLSE), Alveofact, Curosurf and Survanta (all used in clinical, replacement studies in respiratory distress syndrome (RDS) and of an apoprotein-based synthetic phospholipid mixture (PLM-C/B; DPPC:PG:PA = 68.5:22.5:9, supplemented with 2% wt/wt non-palmitoylated human recombinant SP-C and 1% t/wt natural bovine SP-B). In the absence of inhibitory proteins, all surfactants exhibited dose-dependent rapid adsorption (rank order of relative efficacy PLM-C/B = CLSE > Alveofact > Curosurf > Survanta). Minimal surface tension was reduced to near zero values under dynamic compression (rank order PLM-C/B > CLSE > Alveofact = Curosurf) and to approximately 4 mN.m-1 (Survanta). Curosurf and Survanta were dose-dependently inhibited by fibrinogen > haemoglobin > albumin, with far-reaching loss of surface activity at protein-surfactant ratios above 1:1. In contrast, CLSE and Alveofact were only moderately inhibited by fibrinogen, and were not affected by haemoglobin and albumin, up to protein-surfactant ratios of 2:1. PLM-C/B exhibited resistance to fibrinogen, intermediate sensitivity to albumin, and was severely inhibited by haemoglobin. We conclude that various natural surfactant extracts and an apoprotein-based synthetic surfactant mixture markedly differ in their sensitivity to inhibitory plasma proteins.(ABSTRACT TRUNCATED AT 250 WORDS)

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Wang, Zhengdong, Adam Foye, Yusuo Chang, Patricia R. Chess, Terry W. Wright, Samir Bhagwat, Francis Gigliotti e Robert H. Notter. "Inhibition of surfactant activity byPneumocystis cariniiorganisms and components in vitro". American Journal of Physiology-Lung Cellular and Molecular Physiology 288, n.º 6 (junho de 2005): L1124—L1131. http://dx.doi.org/10.1152/ajplung.00453.2004.

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This study examines the direct inhibitory effects of Pneumocystis carinii ( Pc) organisms and chemical components on the surface activity and composition of whole calf lung surfactant (WLS) and calf lung surfactant extract (CLSE) in vitro. Incubation of WLS suspensions with intact Pc organisms (107per milligram of surfactant phospholipid) did not significantly alter total phospholipid levels or surfactant protein A content. Incubation with intact Pc organisms also did not impair dynamic surface tension lowering in suspensions of WLS or centrifuged large surfactant aggregates on a bubble surfactometer (37°C, 20 cycles/min, 0.5 and 2.5 mg phospholipid/ml). However, exposure of WLS or CLSE to disrupted (sonicated) Pc organisms led to severe detriments in activity, with minimum surface tensions of 17–19 mN/m vs. <1 mN/m for surfactants alone. Extracted hydrophobic chemical components from Pc (98.8% lipids, 0.1 mM) reduced the surface activity of WLS and CLSE similarly to sonicated Pc organisms, whereas extracted hydrophilic chemical components from Pc (primarily proteins) had only minor effects on surface tension lowering. These results indicate that in addition to surfactant dysfunction induced by inflammatory lung injury and edema-derived inhibitors in Pc pneumonia, disrupted Pc organisms in the alveolar lumen also have the potential to directly inhibit endogenous and exogenous lung surfactants in affected patients.

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Rahimov, I. "Asymptotic distribution of the CLSE in a critical process with immigration". Stochastic Processes and their Applications 118, n.º 10 (outubro de 2008): 1892–908. http://dx.doi.org/10.1016/j.spa.2007.11.004.

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Karhu, Aino J., Olli J. Pakkanen, J. Mikko Rautiainen, Raija Oilunkaniemi, Tristram Chivers e Risto S. Laitinen. "The role of imidoselenium(ii) chlorides in the formation of cyclic selenium imides via cyclocondensation". Dalton Transactions 45, n.º 14 (2016): 6210–21. http://dx.doi.org/10.1039/c5dt04236d.

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Imidoselenium(ii) chlorides ClSe[N(^tBu)Se]_nCl (n = 1–3) are intermediates in the formation of cyclic selenium imides by the reaction of SeCl₂ and ^tBuNH₂ in THF.

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Toth, Gergo. "Propuesta para tratar temas tabúes y controvertidos en la clse de E/LE." CAUCE (Revista Internacional de Filología, Comunicación y sus Didácticas), n.º 41 (2019): 91–111. https://doi.org/10.12795/cauce.2019.i42.07.

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Las sociedades modernas cada vez se diversifcan más. Junto a los fenómenos existentes aparecen otros nuevos que afrontar. Estos fenómenos pueden considerarse tabúes o temas controvertidos según las características socioculturales de cada país. La normalización de la diversidad y de nuevas realidades es fundamental para construir personalidades sanas. Los docentes tienen gran responsabilidad sobre ello durante el proceso de la enseñanza. Con la Literatura infantil como herramienta en las aulas de segundas lenguas se trabaja con material auténtico que constituye un atractivo y contribuye en la sensibilización de los aprendientes, aumentando su nivel de inteligencia emocional y por consiguiente la tolerancia y la empatía. Siguiendo las directrices de los métodos comunicativos de aprendizaje de idiomas y centrándose en el enfoque por tareas “Titiritesa” de Xerardo Quintiá se convierte en un material didáctico idóneo para el tratamiento de la homosexualidad y el matrimonio entre personas del mismo sexo.

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Haddad, I. Y., H. Ischiropoulos, B. A. Holm, J. S. Beckman, J. R. Baker e S. Matalon. "Mechanisms of peroxynitrite-induced injury to pulmonary surfactants". American Journal of Physiology-Lung Cellular and Molecular Physiology 265, n.º 6 (1 de dezembro de 1993): L555—L564. http://dx.doi.org/10.1152/ajplung.1993.265.6.l555.

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Activated alveolar macrophages secrete both nitric oxide and superoxide in the alveolar lining fluid which combine rapidly to form peroxynitrite, a potent oxidizing agent capable of damaging lipids and proteins in biological membranes. Peroxynitrite (1 mM) plus 100 microM Fe3+EDTA inhibited calf lung surfactant extract (CLSE) from reaching a minimum surface tension below 10 mN/m on dynamic compression. Peroxynitrite and its by-products reacted with the unsaturated lipid components of CLSE, as evidenced by the appearance of conjugated dienes and thiobarbituric acid products, and damaged all surfactant proteins. A mixture of the hydrophobic proteins [surfactant protein B (SP-B) and surfactant protein C (SP-C)] exposed to peroxynitrite became incapable of lowering phospholipid minimum surface tension on dynamic compression. Exposure of SP-A to peroxynitrite decreased its ability to cause lipid aggregation and to act synergistically with SP-B and SP-C in lowering surface tension of surfactant lipids. Western blot analysis of SP-A exposed to peroxynitrite was consistent with fragmentation and polymerization of the 28- to 36-kDa triplet band, and amino acid analysis revealed the presence of significant levels of 3-nitro-L-tyrosine. We conclude that peroxynitrite and its reactive intermediates inhibit pulmonary surfactant function by lipid peroxidation and damaging surfactant proteins.

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Matalon, S., B. A. Holm e R. H. Notter. "Mitigation of pulmonary hyperoxic injury by administration of exogenous surfactant". Journal of Applied Physiology 62, n.º 2 (1 de fevereiro de 1987): 756–61. http://dx.doi.org/10.1152/jappl.1987.62.2.756.

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We studied the effects of surfactant supplementation on the progression of lung injury in rabbits exposed to 100% O2 for 64 h and returned to room air for 24 h. At this time, rabbits not treated with surfactant exhibit a severe lung injury with hypoxemia, increased alveolar premeability to solute, decreased total lung capacity (TLC) and lung edema. For surfactant treatment, 125 mg of calf lung surfactant extract (CLSE), suspended in 6–8 ml of normal saline, were instilled intratracheally at 0 and 12 h posthyperoxic exposure. At 24 h postexposure, these CLSE-treated rabbits compared with saline controls had significantly higher amounts of lung phospolipids (34 +/- 4 vs. 4.5 +/- 0.6 mumol/kg body wt) and increased TLC (42 +/- 2 vs. 27 +/- 1 ml/kg), with significantly lower amounts of alveolar protein (36 +/- 3 vs. 56 +/- 3 mg/kg) and decreased lung wet weight-to-dry weight ratios (5.6 +/- 0.1 vs. 6.3 +/- 0.3). Surfactant supplementation also decreased the degree of lung atelectasis as reflected by the increase in arterial O2 partial pressure (PaO2) after breathing 100% O2 for 20 min (PaO2 = 460 +/- 31 vs. 197 +/- 52 Torr). These findings indicate that instillation of exogenous surfactant mitigates the progression of hyperoxic lung injury in rabbits.

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Haddad, Imad Y., Bedford Nieves-Cruz e Sadis Matalon. "Inhibition of surfactant function by copper-zinc superoxide dismutase (CuZn-SOD)". Journal of Applied Physiology 83, n.º 5 (1 de novembro de 1997): 1545–50. http://dx.doi.org/10.1152/jappl.1997.83.5.1545.

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Haddad, Imad Y., Bedford Nieves-Cruz, and Sadis Matalon.Inhibition of surfactant function by copper-zinc superoxide dismutase (CuZn-SOD). J. Appl. Physiol. 83(5): 1545–1550, 1997.—The efficacy of antioxidant enzymes to limit oxidant lung injury by instillation with surfactant mixtures in preterm infants with hyaline membrane disease is under investigation. However, there is concern that instillation of proteins in the alveolar space may inactivate pulmonary surfactant. We studied the effects of bovine copper-zinc superoxide dismutase (CuZn-SOD) on the biophysical properties of two distinct surfactant preparations. Incubation of calf lung surfactant extract (CLSE, 1 mg phospholipid/ml) and Exosurf (0.1 mg phospholipid/ml) with CuZn-SOD (1–10 mg/ml) prevented the fall of surface tension at minimal bubble radius (Tmin) to low values with dynamic compression in a pulsating bubble surfactometer. CuZn-SOD also enhanced the sensitivity to inactivation by albumin, normal human serum, and after treatment with peroxynitrite. The inhibitory effects of CuZn-SOD on CLSE, but not Exosurf, were abolished at high lipid concentrations (3 mg/ml) and after the addition of human surfactant protein A (by weight). We conclude that CuZn-SOD may interfere with the surface activity of surfactant mixtures, leading to decreased effectiveness of surfactant replacement therapy.

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Liu, M. Y., L. M. Wang, E. Li e G. Enhorning. "Pulmonary surfactant will secure free airflow through a narrow tube". Journal of Applied Physiology 71, n.º 2 (1 de agosto de 1991): 742–48. http://dx.doi.org/10.1152/jappl.1991.71.2.742.

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Well functioning pulmonary surfactant is necessary to ensure alveolar stability. It is proposed that surfactant is also required to keep the finest cylindrical airways open, thereby securing an unrestricted flow of air to and from the alveoli. If the surfactant is inadequate in quality or quality there is a risk that liquid will accumulate in the most marrow section of the airway and form a blocking column. To study that possibility special glass capillaries were used. The glass capillaries were heated and extended to make a short section very narrow. In the lumen of that section a minute volume (1 microliter) of liquid was deposited, which formed a blocking column. When pressure was raised on one side of the column, it forced the liquid to move away from the narrow section. Pressure dropped to zero as air could pass, and if the liquid column consisted of calf lung surfactant extract (CLSE), pressure remained at zero because a new liquid column did not form. If, on the other hand, the liquid column consisted of saline solution it would repeatedly reform as soon as it had been pressed out of the capillary's narrow section. The same occurred if the CLSE suspension forming the liquid column was very dilute or contained inhibiting proteins. These observations did not require that the capillary consisted of the material glass; they were also noted when the narrow tube was outlined by epithelium.

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Wang, Z., J. E. Baatz, B. A. Holm e R. H. Notter. "Content-dependent activity of lung surfactant protein B in mixtures with lipids". American Journal of Physiology-Lung Cellular and Molecular Physiology 283, n.º 5 (1 de novembro de 2002): L897—L906. http://dx.doi.org/10.1152/ajplung.00431.2001.

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The content-dependent activity of surfactant protein (SP)-B was studied in mixtures with dipalmitoyl phosphatidylcholine (DPPC), synthetic lipids (SL), and purified phospholipids (PPL) from calf lung surfactant extract (CLSE). At fixed SP-B content, adsorption and dynamic surface tension lowering were ordered as PPL/SP-B ≈ SL/SP-B > DPPC/SP-B. All mixtures were similar in having increased surface activity as SP-B content was incrementally raised from 0.05 to 0.75% by weight. SP-B had small but measurable effects on interfacial properties even at very low levels ≤0.1% by weight. PPL/SP-B (0.75%) had the highest adsorption and dynamic surface activity, approaching the behavior of CLSE. All mixtures containing 0.75% SP-B reached minimum surface tensions <1 mN/m in pulsating bubble studies at low phospholipid concentration (1 mg/ml). Mixtures of PPL or SL with SP-B (0.5%) also had minimum surface tensions <1 mN/m at 1 mg/ml, whereas DPPC/SP-B (0.5%) reached <1 mN/m at 2.5 mg/ml. Physiological activity also was strongly dependent on SP-B content. The ability of instilled SL/SP-B mixtures to improve surfactant-deficient pressure-volume mechanics in excised lavaged rat lungs increased as SP-B content was raised from 0.1 to 0.75% by weight. This study emphasizes the crucial functional activity of SP-B in lung surfactants. Significant differences in SP-B content between exogenous surfactants used to treat respiratory disease could be associated with substantial activity variations.

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Fajriaty, Inarah, Hariyanto Ih, Irda Fidrianny, Neng Fisheri Kurniati, Muhammad Andre Reynaldi, I. Ketut Adnyana, Rommy Rommy, Fransiska Kurniawan e Daryono Hadi Tjahjono. "In Vivo Pharmacodynamics of Calophyllum soulattri as Antiobesity with In Silico Molecular Docking and ADME/Pharmacokinetic Prediction Studies". Pharmaceuticals 16, n.º 2 (28 de janeiro de 2023): 191. http://dx.doi.org/10.3390/ph16020191.

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This study aims to determine the antiobesity activity of Calophyllum soulattri leaves extract (CSLE) on high fat diet-fed rats (HFD) and to predict the molecular docking and pharmacokinetics of selected compounds of Calophyllum soulattri to fat mass and obesity-associated protein (FTO). Daily body weight, organ, carcass fat (renal and anal), body mass index, total cholesterol, and total triglyceride levels were observed after CSLE was given orally for 50 days. Furthermore, body mass index of a CSLE dose of 50 mg/kgbw, 100 mg/kgbw and orlistat (120 mg/kgbw) group are 0.68, 0.57 and 0.52, respectively. The total body weight of the CLSE dose of 100 mg/kgbw group showed the lowest percentage change, followed by a CLSE dose of 50 mg/kgbw compared to the normal and positive control group. The carcass fat index of CSLE dose of 100 mg/kgbw was not significantly different from orlistat, which was in line with its total cholesterol level and triglyceride (p < 0.05). The binding affinity of selected compounds from Calophyllum soulattri (friedelin, caloxanthone B, macluraxanthone, stigmasterol, trapezifolixanthone, dombakinaxanthone, and brasixanthone B) to FTO are –8.27, –9.74, –8.48, –9.34, –8.85, –8.68 and –9.39 kcal/mol, which are better than that of orlistat at –4.80 kcal/mol. The molecular dynamics simulation showed that the interaction between Caloxanthone B compounds and obesity receptors was relatively stable. Lipinski’s rule determined the absorption percentage of all compounds above 90% with good drug-likeness. The results showed the potential of CSLE as an antiobesity drug candidate.

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Zucker, A. R., B. A. Holm, G. P. Crawford, K. Ridge, L. D. Wood e J. I. Sznajder. "PEEP is necessary for exogenous surfactant to reduce pulmonary edema in canine aspiration pneumonitis". Journal of Applied Physiology 73, n.º 2 (1 de agosto de 1992): 679–86. http://dx.doi.org/10.1152/jappl.1992.73.2.679.

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Alveolar edema inactivates surfactant, and surfactant depletion causes edema by reducing lung interstitial pressure (Pis). We reasoned that surfactant repletion might reduce edema by raising Pis after acute lung injury and that positive end-expiratory pressure (PEEP) might facilitate this effect. One hour after tracheal administration of hydrochloric acid in 18 anesthetized dogs with transmural pulmonary capillary wedge pressure of 8 Torr, the animals were randomized into three groups: in the SURF + PEEP group, 50 mg/kg of calf lung surfactant extract (CLSE) was instilled into each main stem bronchus with 8 cmH2O of PEEP; in the SAL + PEEP group, PEEP was followed by an equal volume of saline (SAL); in the SURF group, CLSE was given without PEEP. After 5 h, edema in excised lungs (wet-to-dry weight ratios) was significantly less in the SURF + PEEP group (9.1 +/- 1.0) than in the other groups (11.3 +/- 1.8 and 11.3 +/- 1.8, respectively). In the SURF + PEEP group, pulmonary venous admixture fell by 6%; this change was different from the 7% increase in the SAL + PEEP group and 40% increase in the SURF group (P less than 0.05). Airway secretions obtained in the SURF + PEEP group had normal minimum surface tensions of 4 +/- 2 mN/m, a value much lower than in SAL + PEEP and SURF groups (32 +/- 4 and 22 +/- 7 mN/m, respectively). We conclude that surfactant normalizes surface tension and decreases transcapillary hydrostatic forces in this lung injury model, thereby reducing edema formation and improving gas exchange. These benefits occur only if surfactant is given with PEEP, allowing surfactant access to the alveoli and/or minimizing its inhibition by edema proteins.

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Maaninen, Tiina, Tristram Chivers, Risto Laitinen e Elina Wegelius. "Acyclic imidoselenium(ii) dihalides: synthesis and X-ray structures of ClSe[N(But)Se]nCl (n = 1, 2)". Chemical Communications, n.º 9 (2000): 759–60. http://dx.doi.org/10.1039/b001002m.

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Gleason, C. A., M. D. Jones, R. J. Traystman e R. H. Notter. "Fetal cerebral responses to ventilation and oxygenation in utero". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 255, n.º 6 (1 de dezembro de 1988): R1049—R1054. http://dx.doi.org/10.1152/ajpregu.1988.255.6.r1049.

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Previous studies have shown that cerebral oxygen consumption (CMRO2) increases by nearly 50% at birth. The perinatal factors responsible for this increase are unknown; however, one possibility is that fetal CMRO2 is constrained by the normal intrauterine arterial PO2 (PaO2) of approximately 20 mmHg. We investigated this possibility in seven near-term chronically instrumented fetal sheep (131-138 days gestation) in which we inserted vascular catheters and an endotracheal tube. After 1-3 days recovery, we measured cerebral blood flow (CBF) with radiolabeled microspheres and calculated CMRO2. Measurements were made in utero under three conditions for each fetus: 1) nonventilated control; 2) ventilation with 3% O2-5% CO2-92% N2; and 3) ventilation with an inspired oxygen concentration sufficient to raise fetal PaO2 to normal newborn levels (mean 73 mmHg). A calf lung surfactant extract (CLSE) was instilled into the endotracheal tube of the fetus before ventilation to ensure adequate levels of alveolar surfactant and to maintain stable pH and arterial PCO2. The results showed that increasing fetal arterial PO2 to postnatal levels did not consistently increase CMRO2. CBF decreased as arterial O2 content (CaO2) rose, with an inverse hyperbolic response similar to that previously found to relate CBF to CaO2 during fetal hypoxic hypoxia. This indicates that the normally low intrauterine PaO2 does not intrinsically limit CMRO2 and implies that the rapid increase in CMRO2 at birth reflects the activation of specific cellular and physiological processes at (or near) this unique developmental event.

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Bakshi, Pradip, Paul D. Boyle, T. Stanley Cameron, Jack Passmore, Gabriele Schatte e George W. Sutherland. "Preparations, X-ray Crystal Structures, and FT-Raman Spectra of M3Cl3AsF6 (M = S, Se) Containing the Novel Sulfur-Chlorine and Selenium-Chlorine Cations ClS+(Cl)SSCl and ClSe+(Cl)SeSeCl". Inorganic Chemistry 33, n.º 18 (agosto de 1994): 3849–51. http://dx.doi.org/10.1021/ic00096a001.

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BAKSHI, P., P. D. BOYLE, T. S. CAMERON, J. PASSMORE, G. SCHATTE e G. W. SUTHERLAND. "ChemInform Abstract: Preparations, X-Ray Crystal Structures, and FT-Raman Spectra of M3Cl3AsF6 (M: S, Se) Containing the Novel Sulfur-Chlorine and Selenium- Chlorine Cations ClS+(Cl)SSCl and ClSe+(Cl)SeSeCl." ChemInform 26, n.º 15 (18 de agosto de 2010): no. http://dx.doi.org/10.1002/chin.199515014.

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Bílek, L., S. Vacek, Z. Vacek, J. Remeš, J. Král, D. Bulušek e J. Gallo. "How close to nature is close-to-nature pine silviculture?" Journal of Forest Science 62, No. 1 (3 de junho de 2016): 24–34. http://dx.doi.org/10.17221/98/2015-jfs.

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Coronas-Cabrero, Mariano. "El periódico en clase". Comunicar 5, n.º 9 (1 de outubro de 1997): 144–48. http://dx.doi.org/10.3916/c09-1997-22.

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El autor de este trabajo relata el plan de actividades con la prensa, llevado a cabo en 5º de Primaria durante el curso escolar 1995/96. El aprovechamiento realizado abarca actividades iniciales de conocimiento y sensibilización, entre las que se incluye la visita a las instalaciones de un periódico, el desarrollo de actividades colectivas y aquellas otras que se resolvieron de manera individual. Todo ello dentro de un plan de trabajo establecido desde principio de curso.

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Douglass, Martin V., François Cléon e M. Stephen Trent. "Cardiolipin aids in lipopolysaccharide transport to the gram-negative outer membrane". Proceedings of the National Academy of Sciences 118, n.º 15 (8 de abril de 2021): e2018329118. http://dx.doi.org/10.1073/pnas.2018329118.

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In Escherichia coli, cardiolipin (CL) is the least abundant of the three major glycerophospholipids in the gram-negative cell envelope. However, E. coli harbors three distinct enzymes that synthesize CL: ClsA, ClsB, and ClsC. This redundancy suggests that CL is essential for bacterial fitness, yet CL-deficient bacteria are viable. Although multiple CL–protein interactions have been identified, the role of CL still remains unclear. To identify genes that impact fitness in the absence of CL, we analyzed high-density transposon (Tn) mutant libraries in combinatorial CL synthase mutant backgrounds. We found LpxM, which is the last enzyme in lipid A biosynthesis, the membrane anchor of lipopolysaccharide (LPS), to be critical for viability in the absence of clsA. Here, we demonstrate that CL produced by ClsA enhances LPS transport. Suppressors of clsA and lpxM essentiality were identified in msbA, a gene that encodes the indispensable LPS ABC transporter. Depletion of ClsA in ∆lpxM mutants increased accumulation of LPS in the inner membrane, demonstrating that the synthetic lethal phenotype arises from improper LPS transport. Additionally, overexpression of ClsA alleviated ΔlpxM defects associated with impaired outer membrane asymmetry. Mutations that lower LPS levels, such as a YejM truncation or alteration in the fatty acid pool, were sufficient in overcoming the synthetically lethal ΔclsA ΔlpxM phenotype. Our results support a model in which CL aids in the transportation of LPS, a unique glycolipid, and adds to the growing repertoire of CL–protein interactions important for bacterial transport systems.

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Castro-Rodríguez, María-del-Carmen. "¿Periódicos en clase de inglés?" Comunicar 4, n.º 7 (1 de outubro de 1996): 110–13. http://dx.doi.org/10.3916/c07-1996-21.

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Se nos relata una experiencia de un Seminario Permanente para la utilización de la prensa como recurso didáctico en el área de Inglés. A través de las distintas actividades realizadas, podemos observar cómo la prensa en español también puede servir para el aprendizaje de una lengua extranjera de una forma mucho más motivadora y actualizada. La autora utiliza, además de la prensa, otros recursos audiovisuales, como los cómics, carteles, etc.

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Nguyen, April, Vinathi Polamraju, Truc T. Tran, Diana Panesso-Botero, Ayesha Khan, Eugenia Mileykovskaya, Heidi Vitrac e Cesar A. Arias. "1446. Dynamics of Enterococcus faecalis Cardiolipin Synthase Gene Expression Reveal Compensatory Roles in Daptomycin Resistance". Open Forum Infectious Diseases 7, Supplement_1 (1 de outubro de 2020): S726. http://dx.doi.org/10.1093/ofid/ofaa439.1627.

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Abstract Background Daptomycin (DAP) is a lipopeptide antibiotic targeting membrane anionic phospholipids (APLs) at the division septum, and resistance (DAP-R) has been linked to mutations in genes encoding i) the LiaFSR stress response system or its effector LiaX, and ii) cardiolipin synthase (Cls). Activation of the E. faecalis (Efs) LiaFSR response is associated with DAP-R and redistribution of APL microdomains away from the septum, and cardiolipin is predicted to be a major component of these APL microdomains. Efs harbors two putative cls genes, cls1 and cls2. While changes in Cls1 have been implicated in DAP-R, the exact roles of each enzyme in resistance are unknown. We aim to characterize the contributions of Cls1 and Cls2 in the development of DAP-R. Methods cls1 and cls2 were deleted individually and in tandem from DAP-S Efs OG117 and DAP-R Efs OG117∆liaX (a DAP-R derivative strain with an activated LiaFSR response). Mutants were characterized by DAP minimum inhibitory concentration (MIC) using E-test on Mueller-Hinton II agar and localization of APL microdomains with 10-N-nonyl-acridine orange staining. Quantitative PCR (qRT-PCR) was used to study gene expression profiles of cls1 and cls2 in Efs OG117∆liaX relative to Efs OG117 across the cell growth cycle. Results qRT-PCR revealed differential expression profiles of cls1 and cls2 associated with DAP-R. cls1 was highly upregulated in stationary phase concurrent with a decrease in cls2 expression. However, independent deletion of cls1 or cls2 in the DAP-R background resulted in no significant changes in DAP MICs or localization of APL microdomains (remaining non-septal). Further studies revealed that cls2 expression is upregulated upon deletion of cls1 in both the DAP-S and DAP-R background, suggesting a potential compensatory role for Cls2. Double deletion of both cls genes in the DAP-R strain decreased DAP MIC and restored the septal localization of APL microdomains. Conclusion Cls1 is the major and predominant enzyme involved in cell membrane adaptation associated with the development of DAP-R in E. faecalis. However, we describe a novel compensatory and overlapping role for cardiolipin synthases to ensure bacterial survival upon attack from antimicrobial peptides and related antibiotics. Disclosures Cesar A. Arias, MD, MSc, PhD, FIDSA, Entasis Therapeutics (Scientific Research Study Investigator)MeMed (Scientific Research Study Investigator)Merck (Grant/Research Support)

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König, Peter, Gabriela Krasteva, Claudia Tag, Inke R. König, Christoph Arens e Wolfgang Kummer. "FRET–CLSM and double-labeling indirect immunofluorescence to detect close association of proteins in tissue sections". Laboratory Investigation 86, n.º 8 (19 de junho de 2006): 853–64. http://dx.doi.org/10.1038/labinvest.3700443.

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Ohniwa, Ryosuke L., Kana Kitabayashi e Kazuya Morikawa. "Alternative cardiolipin synthase Cls1 compensates for stalled Cls2 function inStaphylococcus aureusunder conditions of acute acid stress". FEMS Microbiology Letters 338, n.º 2 (22 de novembro de 2012): 141–46. http://dx.doi.org/10.1111/1574-6968.12037.

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Nguyen, April, Vinathi Polamraju, Rutan Zhang, Truc T. Tran, Diana Panesso, Ayesha Khan, Eugenia Mileykovskaya et al. "1275. Dynamics of Enterococcus faecalis Cardiolipin Synthase Gene Expression Reveal Compensatory Roles in Daptomycin Resistance". Open Forum Infectious Diseases 8, Supplement_1 (1 de novembro de 2021): S726. http://dx.doi.org/10.1093/ofid/ofab466.1467.

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Abstract Background Daptomycin (DAP) is a lipopeptide antibiotic targeting membrane anionic phospholipids (APLs) at the division septum, and resistance (DAP-R) has been associated with activation of the E. faecalis (Efs) LiaFSR response and redistribution of APL microdomains (predicted to contain cardiolipin) away from the septum. Efs encodes two putative cardiolipin synthase genes, cls1 and cls2. While changes in Cls1 are associated with DAP-R, the exact roles of each enzyme in resistance are unknown. This work aims to establish the contributions for both enzymes in the development of DAP-R. Methods cls1 and cls2 were deleted individually and in tandem from Efs OG117∆liaX (a DAP-R strain with an activated LiaFSR response). Mutants were characterized by DAP minimum inhibitory concentration (MIC) using E-test and localization of APL microdomains with 10-N-nonyl-acridine orange staining. Quantitative PCR (qRT-PCR) was used to study gene expression profiles of cls1 and cls2 in Efs OG117∆liaX relative to Efs OG117. Membrane lipid content was analyzed using hydrophilic interaction chromatography-mass spectrometry (HILIC-MS). Results cls1 was highly upregulated in stationary phase concurrent with a decrease in cls2 expression. However, independent deletion of cls1 or cls2 in the DAP-R background resulted in no significant phenotypic changes from the parent strain. Interestingly, qRT-PCR showed that cls2 expression was upregulated upon deletion of cls1 (and vice-versa), suggesting a compensatory role for one enzyme upon deletion of the other (Fig 1). When comparing membrane lipid content between Efs OG117∆liaX∆cls1 and Efs OG117∆liaX∆cls2, there were no significant differences in both the overall amount or species of cardiolipin generated, further supporting a potential redundancy between the cardiolipin synthases (Fig 2). Ultimately, double deletion of both cls genes lowered the DAP MIC relative to the parent strain and restored septal localization of APL microdomains. Conclusion Overall, Cls1 has a predominant role in the development of DAP-R in E. faecalis. However, here, we describe a novel compensatory role for Cls2 under conditions in which there is no functional Cls1 to maintain the DAP-R phenotype. Disclosures Truc T. Tran, PharmD, Merck (Grant/Research Support) Cesar A. Arias, M.D., MSc, Ph.D., FIDSA, Entasis Therapeutics (Grant/Research Support)MeMed Diagnostics (Grant/Research Support)Merk (Grant/Research Support)

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WANG, WEI. "On the "Close" Technique of Treble". Convergence of Humanities Social Science an Art’s Academy 5, n.º 1 (28 de fevereiro de 2021): 17–30. http://dx.doi.org/10.37846/soch.3.2.17.

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Lope Blanch, Juan M. "Una clase olvidada de oraciones sustantivas". Revista de Filología Española 73, n.º 1/2 (30 de junho de 1993): 65–68. http://dx.doi.org/10.3989/rfe.1993.v73.i1/2.556.

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Dorn, Gerald W., e Luca Scorrano. "Two Close, Too Close". Circulation Research 107, n.º 6 (17 de setembro de 2010): 689–99. http://dx.doi.org/10.1161/circresaha.110.225714.

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Mitochondria are key organelles in cell life whose dysfunction is associated with a variety of diseases. Their crucial role in intermediary metabolism and energy conversion makes them a preferred target in tissues, such as the heart, where the energetic demands are very high. In the cardiomyocyte, the spatial organization of mitochondria favors their interaction with the sarcoplasmic reticulum, thereby offering a mechanism for Ca 2+ -mediated crosstalk between these 2 organelles. Recently, the molecular basis for this interaction has begun to be unraveled, and we are learning how endoplasmic reticulum–mitochondrial interactions are often exploited by death signals, such as proapoptotic Bcl-2 family members, to amplify the cell death cascade. Here, we review our present understanding of the structural basis and the functional consequences of the close interaction between sarcoplasmic reticulum and mitochondria on cardiomyocyte function and death.

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Landale, Anthony. "Get close, stay close". Industrial and Commercial Training 36, n.º 1 (janeiro de 2004): 35–37. http://dx.doi.org/10.1108/00197850410516102.

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Nguyen, April, Truc T. Tran, Diana Panesso, Ayesha Khan, Eugenia Mileykovskaya, Heidi Vitrac e Cesar A. Arias. "602. Mechanism of LiaY-Mediated Daptomycin Resistance in Enterococcus faecalis". Open Forum Infectious Diseases 6, Supplement_2 (outubro de 2019): S282. http://dx.doi.org/10.1093/ofid/ofz360.671.

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Abstract Background Daptomycin (DAP) is a lipopeptide antibiotic that targets the cell membrane (CM) at the division septum. DAP resistance (DAP-R) in E. faecalis (Efs) has been linked to mutations in genes encoding the LiaFSR stress response system and lipid biosynthetic enzymes, including cardiolipin synthase (Cls). The signature phenotype of DAP-R is redistribution of CM anionic phospholipid (APL) microdomains. Using a genetic approach, we have identified a transmembrane protein (LiaY) as a major mediator of cell membrane APL redistribution associated with DAP-R. Here, we explore the mechanism of LiaY-mediated changes in the CM under the hypothesis that CM remodeling occurs through interactions with Cls. Methods Efs encodes two cls genes (cls1 and cls2). Deletion mutants of both cls genes were generated using the Crispr/cas9 system in the daptomycin-sensitive strain Efs OG117 and Efs OG117∆liaX (a DAP-R derivative of OG117). DAP minimum inhibitory concentration (MIC) was determined using E-test on Mueller–Hinton II agar. Visualization of APL microdomains was performed by staining mid-logarithmic phase cells with 1 µM of 10-N-nonyl-acridine orange (NAO) and fluorescence microscopy. Bacterial two-hybrid system was used to study interactions between LiaY with Cls1 or Cls2. Results Single or double deletion of cls1 or cls2 in Efs OG117 did not affect DAP MIC, and no changes in CM architecture were seen by NAO staining. In contrast,deletion of cls1 (alone or in conjunction with a deletion of cls2) in a DAP-R derivative of OG117 OG117∆liaX, resulted in a marked decrease in DAP MIC, and NAO staining of Efs OG117∆liaX∆cls1∆cls2 shows a restoration of septal APL microdomain localization.In the same DAP-R background, deletion of cls2 alone did not have any effect on DAP MIC or APL microdomain distribution. Additionally, bacterial two-hybrid assays showed a positive interaction of LiaY with Cls1 but not with Cls2. Conclusion We have identified the biochemical basis for DAP-R associated CM remodeling. In a proposed model, the LiaR-mediated activation of the LiaY triggers specific interactions with Cls1 displacing the protein away from the septum, resulting in local generation of APL microdomains that prevents DAP-mediated damage to the CM. Disclosures All authors: No reported disclosures.

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Corson, Jordan. "Reading Derrida close reading Lemov close reading close reading". Educational Philosophy and Theory 52, n.º 3 (23 de junho de 2019): 240–50. http://dx.doi.org/10.1080/00131857.2019.1631156.

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Lin, Shen (Lamson), Karen Kobayashi, Hongmei Tong, Karen M. Davison, Simran R. A. Arora e Esme Fuller-Thomson. "Close Relations Matter: The Association Between Depression and Refugee Status in the Canadian Longitudinal Study on Aging (CLSA)". Journal of Immigrant and Minority Health 22, n.º 5 (23 de janeiro de 2020): 946–56. http://dx.doi.org/10.1007/s10903-020-00980-0.

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Schinnenburg, Heike, e Marlene Walk. "How Close Is Too Close?" Journal of Nonprofit Education and Leadership 8, n.º 1 (2018): 104–10. http://dx.doi.org/10.18666/jnel-2018-v8-i1-8401.

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Geist, Val. "How Close Is Too Close?" Wildlife Professional 1, n.º 1 (2007): 34. http://dx.doi.org/10.4004/1933-2866(2007)1[34:hcitc]2.0.co;2.

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McDonald, J. C. "How close is close enough?" Radiation Protection Dosimetry 130, n.º 2 (15 de dezembro de 2007): 123–24. http://dx.doi.org/10.1093/rpd/ncn196.

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Cummins, Ben, Greg Spitz, Tara P. O'Malley e Margaret Campbell. "How Close is Close Enough?" Transportation Research Record: Journal of the Transportation Research Board 2351, n.º 1 (janeiro de 2013): 23–29. http://dx.doi.org/10.3141/2351-03.

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Owton, Helen, e Jacquelyn Allen-Collinson. "Close But Not Too Close". Journal of Contemporary Ethnography 43, n.º 3 (22 de julho de 2013): 283–305. http://dx.doi.org/10.1177/0891241613495410.

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Daemen, J. "Close, but not close enough". Netherlands Heart Journal 22, n.º 11 (10 de outubro de 2014): 510–12. http://dx.doi.org/10.1007/s12471-014-0611-3.

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Gewirtz, Henry. "How Close Is Close Enough?" JACC: Cardiovascular Imaging 7, n.º 11 (novembro de 2014): 1128–29. http://dx.doi.org/10.1016/j.jcmg.2014.09.001.

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