A crossover control study of three methods of heat acclimation on the magnitude and kinetics of adaptation

2021 ◽  
Author(s):  
Lorenz S. Kissling ◽  
Ashley P. Akerman ◽  
Holly A. Campbell ◽  
Jamie R. Prout ◽  
Travis D. Gibbons ◽  
...  
Keyword(s):  
Heat Acclimation ◽  
Kinetics Of ◽  
Control Study

scholarly journals Kinetics of SARS-CoV-2 antibody responses pre-COVID-19 and post-COVID-19 convalescent plasma transfusion in patients with severe respiratory failure: an observational case–control study

2021 ◽  
pp. jclinpath-2020-207356
Author(s):  
Matthew N Klein ◽  
Elizabeth Wenqian Wang ◽  
Paul Zimand ◽  
Heather Beauchamp ◽  
Caitlin Donis ◽  
...  
Keyword(s):  
Respiratory Failure ◽  
Clinical Outcomes ◽  
Ecmo Support ◽  
Survival Duration ◽  
Severe Respiratory Failure ◽  
Loess Regression ◽  
Antibody Titres ◽  
Similar Survival ◽  
Kinetics Of ◽  
Control Study

AimsWhile the SARS-CoV-2 pandemic may be contained through vaccination, transfusion of convalescent plasma (CCP) from individuals who recovered from COVID-19 (CCP) is considered an alternative treatment. We investigate if CCP transfusion in patients with severe respiratory failure increases plasma titres of SARS-CoV-2 antibodies and improves clinical outcomes.MethodsPatients with COVID-19 (n=34) were consented for CCP transfusion and serial blood draws pretransfusion and post-transfusion. Plasma SARS-CoV-2 antireceptor binding domain (RBD) IgG and IgM titres were measured by ELISA serially, and compared with serial plasma titre levels from control patients (n=68). The primary outcome was survival at 30 days, and secondary outcomes were length of ventilator and/or extracorporeal membrane oxygenation (ECMO) support, length of stay (LOS) in the hospital and in the intensive care unit (ICU). Outcomes were compared with matched control patients (n=34). Kinetics of antibodies and clinical outcomes were compared using LOess regression and ORs, respectively.ResultsPrior to CCP transfusion, 74% of patients were anti-RBD seropositive for IgG (median 1:3200), and 81% were anti-RBD IgM seropositive (median 1:320), while 16% were seronegative. The kinetics of antibody titres in CCP recipients were similar to controls. CCP recipients presented with similar survival, duration on ventilatory and/or ECMO support, as well as ICU and hospital LOS compared with controls.ConclusionsCCP transfusion did not increase the kinetics of SARS-CoV2 antibodies and did not result in improved clinical outcomes in patients with COVID-19 with severe respiratory failure, suggesting that CCP may not be indicated in this category of patients.

Heat acclimation memory: do the kinetics of the deacclimated transcriptome predispose to rapid reacclimation and cytoprotection?

2014 ◽  
Vol 117 (11) ◽  
pp. 1262-1277 ◽  
Author(s):  
Anna Tetievsky ◽  
Miri Assayag ◽  
Rotem Ben-Hamo ◽  
Sol Efroni ◽  
Gal Cohen ◽  
...  
Keyword(s):  
Heat Acclimation ◽  
Left Ventricular ◽  
Molecular Memory ◽  
Transcriptional Responses ◽  
Linker Histones ◽  
Chromatin Compaction ◽  
Physiological Adaptations ◽  
C 30 ◽  
Kinetics Of ◽  
Mrna Hybridization

Faster reinduction of heat acclimation (AC) after its decline indicates “AC memory.” Our previous results revealed involvement of epigenetic mechanisms of transcriptional regulation. We hypothesized that the decline of AC (DeAC) is a period of “dormant memory” during which many processes are alerted to enable rapid reacclimation (ReAC). Using a genomewide approach we studied the AC, DeAC, and ReAC transcriptomes, to uncover hallmark pathways linked to “molecular memory” in the cardioacclimatome. Fifty rats subjected to heat acclimation [34°C for 2d (AC2d) or 30d (AC30)], DeAC (24°C, 30 days), ReAC (34°C, 2 days), and untreated controls were used. The GeneChip Rat Gene 1.0 ST Array was employed for left ventricular (cardiac) mRNA hybridization. Three independent bioinformatic analyses showed that 1) during AC2d enrichment of DNA impair/repair-linked genes is seen, and this is the molecular on-switch of acclimation; 2) genes activated in AC30 underlie the qualitative physiological adaptations of cardiac performance; 3) particular molecular programs encompassing constitutive upregulation of p38 MAPK, Jak/Stat, and Akt pathways and targets are specifically activated during DeAC and ReAC; and 4) epigenetic markers such as linker histones (histones H1 cluster), associated with nucleosome spacing, transcriptional chromatin modifiers, poly-(ADP-ribose) polymerase-1 (PARP1) linked to chromatin compaction, and microRNAs are only altered during DeAC/ReAC. The latter are newcomers to the AC/DeAC puzzle. We suggest that these transcriptional responses maintain euchromatin and proteostasis and enable faster physiological recovery upon ReAC by rapidly reestablishing the protected acclimated cardiophenotype. We propose that the cardiac AC model can be applied to acclimation processes in general.

Oxoproline kinetics and oxoproline urinary excretion during glycine- or sulfur amino acid-free diets in humans

2000 ◽  
Vol 278 (5) ◽  
pp. E868-E876 ◽  
Author(s):  
Cornelia C. Metges ◽  
Yong-Ming Yu ◽  
Wei Cai ◽  
Xiao-Ming Lu ◽  
Sue Wong ◽  
...  
Keyword(s):  
Amino Acid ◽  
Urinary Excretion ◽  
Control Diet ◽  
Amino Acid Mixture ◽  
Acid Mixture ◽  
Sulfur Amino Acid ◽  
Oxidation Rates ◽  
Acute Changes ◽  
Kinetics Of ◽  
Control Study

l-5-oxoproline (l-5-OP) is an intermediate in glutathione synthesis, possibly limited by cysteine availability. Urinary 5-OP excretion has been proposed as a measure of glycine availability. We investigated whether 5 days of dietary sulfur amino acid (SAA-free) or glycine (Gly-free) restriction affects plasma kinetics of 5-OP and urinary excretion of l- andd-5-OP in 6 healthy men. On day 6, l-5-[1-13C]oxoproline and [3,3-2H2]cysteine were infused intravenously for 8 h (3 h fast/5 h fed). In a control study (adequate amino acid mixture), plasma oxoproline fluxes were 37.8 ± 13.8 (SD) and 38.4 ± 14.8 μmol ⋅ kg−1⋅ h−1; oxidation accounted for 85% of flux. Cysteine flux was 47.9 ± 8.5 and 43.2 ± 8.5 μmol ⋅ kg−1⋅ h−1for fast and fed phases, respectively. Urinary excretion ofl- and d-5-OP was 70 ± 34 and 31.1 ± 13.3 μmol/mmol creatinine, respectively, during days 3–5, and 46.4 ± 13.9 and 22.4 ± 8.3 μmol/mmol over the 8-h tracer study. The 5-OP flux for the Gly-free diet was higher ( P = 0.018) and tended to be higher for the SAA-free diet ( P = 0.057) when compared with the control diet. Oxidation rates were higher on the Gly-free ( P = 0.005) and SAA-free ( P = 0.03) diets. Cysteine fluxes were lower on the the Gly-free ( P= 0.01) and the SAA-free diets ( P = 0.001) compared with the control diet. Rates of l-5-OP excretion were unchanged by withdrawal of SAA or Gly for 5 days but increased on day 6( P = 0.005 and P = 0.019, respectively). Thus acute changes in the dietary availability of SAA and Gly alter oxoproline kinetics and urinary 5-OP excretion.

Short-term Heat Acclimation Training Does Not Improve Kinetics Of Lactate Removal Following Maximal Exercise

2014 ◽  
Vol 46 ◽  
pp. 657
Author(s):  
Travis DiLeo ◽  
Jeffrey Powell ◽  
Raymond Roberge ◽  
Aitor Coca ◽  
Kim Jung-Hyun
Keyword(s):  
Maximal Exercise ◽  
Heat Acclimation ◽  
Short Term ◽  
Lactate Removal ◽  
Kinetics Of

scholarly journals Kinetics of SARS-CoV-2 antibody responses pre- and post- COVID-19 convalescent plasma transfusion in patients with severe respiratory failure: an observational case-control study

2020 ◽  
Author(s):  
Matthew N. Klein ◽  
Elizabeth Wenqian Wang ◽  
Paul Zimand ◽  
Heather Beauchamp ◽  
Caitlin Donis ◽  
...  
Keyword(s):  
Respiratory Failure ◽  
Ecmo Support ◽  
Control Group ◽  
Severe Respiratory Failure ◽  
Before And After ◽  
Life Threatening ◽  
Antibody Titers ◽  
Similar Survival ◽  
Kinetics Of ◽  
Control Study

ABSTRACTOBJECTIVESTo investigate if COVID-19 convalescent plasma (CCP) transfusion in patients with severe respiratory failure will increase plasma levels of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) antibody titers while improving survival and clinical outcomes.DESIGNObservational, retrospective, control study of anti-Receptor binding domain (RBD) of SARS-CoV-2 IgG and IgM titers from serial plasma samples drawn before and after CCP administration. Clinical improvement in CCP recipients is assessed and compared to COVID-19 control patients.SETTINGPatients hospitalized with severe COVID19, United States, between April 17 and July 19, 2020PARTICIPANTS34 patients hospitalized with severe or life threatening COVID-19 and who consented and received a CCP transfusion, 95 control patients with COVID-19 not transfused with CCP. 34 out the 95 control patients were matched for age, sex, and the level of respiratory support required. Patients less than 18 years old were excluded.MAIN OUTCOME MEASURESSerial trends of anti-RBD of SARS-CoV-2 IgG and IgM titers in CCP recipients are compared to those in control patients. The primary outcome is survival at 30 days, and the secondary outcomes are length of ventilatory and/or extracorporeal membrane oxygenation (ECMO) support, length of stay (LOS) in the hospital, and LOS in the ICU.RESULTSCCP transfusion occurred in 34 patients at a median of 12 days following COVID-19 symptom onset. Immediately prior to CCP transfusion, patients median anti-RBD SARS-CoV-2 IgG and IgM titers were 1:3200 (IQR, 1:50 to 1:9600) and 1:320 (IQR, 1:40 to 1:640) respectively. Following a Loess regression analysis, the kinetics and distribution of anti-RBD of SARS-CoV-2 IgG and IgM in plasma from CCP recipients were comparable to those from a control group of 68 patients who did not receive CCP. CCP recipients presented with similar survival, similar duration on ventilatory and/or ECMO support, as well as ICU and hospital LOS, compared to a matched control group of 34 patients.CONCLUSIONIn the present study, hospitalized COVID-19 patients with severe respiratory failure transfused with CCP presented with high titers of SARS-CoV-2 IgG antibodies before transfusion and did not show improved survival at 30 days.

Direct observations of radiation-enhanced transformations in glass

1983 ◽  
Vol 41 ◽  
pp. 354-355
Author(s):  
J. F. DeNatale ◽  
D. G. Howitt
Keyword(s):  
Glass Matrix ◽  
Diffusion Mechanism ◽  
Bubble Formation ◽  
Silicate Glasses ◽  
Phase Decomposition ◽  
Direct Observations ◽  
Thin Foils ◽  
Oxygen Bubble ◽  
Electron Energy Loss ◽  
Kinetics Of

The electron irradiation of silicate glasses containing metal cations produces various types of phase separation and decomposition which includes oxygen bubble formation at intermediate temperatures figure I. The kinetics of bubble formation are too rapid to be accounted for by oxygen diffusion but the behavior is consistent with a cation diffusion mechanism if the amount of oxygen in the bubble is not significantly different from that in the same volume of silicate glass. The formation of oxygen bubbles is often accompanied by precipitation of crystalline phases and/or amorphous phase decomposition in the regions between the bubbles and the detection of differences in oxygen concentration between the bubble and matrix by electron energy loss spectroscopy cannot be discerned (figure 2) even when the bubble occupies the majority of the foil depth.The oxygen bubbles are stable, even in the thin foils, months after irradiation and if van der Waals behavior of the interior gas is assumed an oxygen pressure of about 4000 atmospheres must be sustained for a 100 bubble if the surface tension with the glass matrix is to balance against it at intermediate temperatures.

Irradiation behavior of pyrolytic silicon carbide

1983 ◽  
Vol 41 ◽  
pp. 72-73
Author(s):  
R. J. Lauf
Keyword(s):  
Silicon Carbide ◽  
Fission Products ◽  
Thermodynamics And Kinetics ◽  
Neutron Fluences ◽  
Fuel Particles ◽  
Sic Coatings ◽  
Irradiation Behavior ◽  
Kinetics Of ◽  
Htgr Fuel

Fuel particles for the High-Temperature Gas-Cooled Reactor (HTGR) contain a layer of pyrolytic silicon carbide to act as a miniature pressure vessel and primary fission product barrier. Optimization of the SiC with respect to fuel performance involves four areas of study: (a) characterization of as-deposited SiC coatings; (b) thermodynamics and kinetics of chemical reactions between SiC and fission products; (c) irradiation behavior of SiC in the absence of fission products; and (d) combined effects of irradiation and fission products. This paper reports the behavior of SiC deposited on inert microspheres and irradiated to fast neutron fluences typical of HTGR fuel at end-of-life.

The Ordered Phase Formation in Ti-Al-Ga Alloys

1970 ◽  
Vol 28 ◽  
pp. 440-441
Author(s):  
Shiro Fujishiro ◽  
Harold L. Gegel
Keyword(s):  
Thermal Stability ◽  
High Temperature ◽  
Titanium Alloys ◽  
Growth Kinetics ◽  
Stoichiometric Composition ◽  
Good Potential ◽  
Alpha Titanium ◽  
Cold Rolled ◽  
Kinetics Of ◽  
Thermal Stability Of

Ordered-alpha titanium alloys having a DO19 type structure have good potential for high temperature (600°C) applications, due to the thermal stability of the ordered phase and the inherent resistance to recrystallization of these alloys. Five different Ti-Al-Ga alloys consisting of equal atomic percents of aluminum and gallium solute additions up to the stoichiometric composition, Ti3(Al, Ga), were used to study the growth kinetics of the ordered phase and the nature of its interface.The alloys were homogenized in the beta region in a vacuum of about 5×10-7 torr, furnace cooled; reheated in air to 50°C below the alpha transus for hot working. The alloys were subsequently acid cleaned, annealed in vacuo, and cold rolled to about. 050 inch prior to additional homogenization

Ion Beam Induced Interfacial Reactions in Molybdenum Thin Films on Silicon

1981 ◽  
Vol 39 ◽  
pp. 162-163
Author(s):  
L. J. Chen ◽  
L. S. Hung ◽  
J. W. Mayer
Keyword(s):  
Ion Beam ◽  
Chemical Vapor ◽  
Interfacial Reactions ◽  
Practical Applications ◽  
Microelectronic Devices ◽  
Recent Emergence ◽  
Chemical Vapor Deposited ◽  
Atomic Mixing ◽  
Silicon Interface ◽  
Kinetics Of

When an energetic ion penetrates through an interface between a thin film (of species A) and a substrate (of species B), ion induced atomic mixing may result in an intermixed region (which contains A and B) near the interface. Most ion beam mixing experiments have been directed toward metal-silicon systems, silicide phases are generally obtained, and they are the same as those formed by thermal treatment.Recent emergence of silicide compound as contact material in silicon microelectronic devices is mainly due to the superiority of the silicide-silicon interface in terms of uniformity and thermal stability. It is of great interest to understand the kinetics of the interfacial reactions to provide insights into the nature of ion beam-solid interactions as well as to explore its practical applications in device technology.About 500 Å thick molybdenum was chemical vapor deposited in hydrogen ambient on (001) n-type silicon wafer with substrate temperature maintained at 650-700°C. Samples were supplied by D. M. Brown of General Electric Research & Development Laboratory, Schenectady, NY.

In situ study of electron beam-induced chemical vapor deposition of Au in an environmental TEM

1995 ◽  
Vol 53 ◽  
pp. 256-257
Author(s):  
J. Drucker ◽  
R. Sharma ◽  
J. Kouvetakis ◽  
K.H.J. Weiss
Keyword(s):  
Electron Beam ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Quantum Effect ◽  
Line Drawing ◽  
Chemical Vapor ◽  
Environmental Cell ◽  
Engineering Changes ◽  
Kinetics Of

Patterning of metals is a key element in the fabrication of integrated microelectronics. For circuit repair and engineering changes constructive lithography, writing techniques, based on electron, ion or photon beam-induced decomposition of precursor molecule and its deposition on top of a structure have gained wide acceptance Recently, scanning probe techniques have been used for line drawing and wire growth of W on a silicon substrate for quantum effect devices. The kinetics of electron beam induced W deposition from WF6 gas has been studied by adsorbing the gas on SiO2 surface and measuring the growth in a TEM for various exposure times. Our environmental cell allows us to control not only electron exposure time but also the gas pressure flow and the temperature. We have studied the growth kinetics of Au Chemical vapor deposition (CVD), in situ, at different temperatures with/without the electron beam on highly clean Si surfaces in an environmental cell fitted inside a TEM column.

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