Comparison of anticoagulation monitoring strategies for adults supported on extracorporeal membrane oxygenation: A systematic review.

BACKGROUND: Anticoagulation is critical in patients supported on extracorporeal membrane oxygenation (ECMO). The appropriate monitoring strategies for heparin remain unclear. OBJECTIVES: This systematic review aimed to compare the accuracy and safety of various monitoring strategies for patients supported on ECMO. METHODS: The PubMed and Web of Science databases were searched for articles in March 2023 without restrictions on publication date. Anticoagulation monitoring strategies for adults supported on ECMO were compared across all included studies. The incidence of bleeding, thrombosis, mortality, blood transfusion, correlation between tests and heparin dose, and the discordance between different tests were discussed in the included studies. The risk of bias was assessed using the Newcastle-Ottawa Scale and Cochrane Collaboration's tool. RESULTS: Twenty-six studies, including a total of 1,684 patients, met the inclusion criteria. The monitoring of anticoagulation by activated partial thromboplastin time (aPTT) resulted in less blood product transfusion than that by activated clotting time (ACT). Moreover, the monitoring of anticoagulation by anti-factor Xa (Anti-Xa) resulted in a more stable anticoagulation than that by aPTT. Anti-Xa and aPTT correlated with heparin dose better than ACT, and the discordance between different monitoring tests was common. Finally, combined monitoring showed some advantages in reducing mortality and blood product transfusion. CONCLUSION: Anti-Xa and aPTT are more suitable for anticoagulation monitoring for patients supported on ECMO than ACT. Thromboelastography and combination strategies are less applied. Most of the studies were retrospective, and their sample sizes were relatively small; thus, more appropriate monitoring strategies and higher quality research are needed.

Formation process of Cu2(OH)2CO3 and CuO hierarchical nanostructures by assembly of hydrated nanoparticles.

Cu2(OH)2CO3 and CuO hierarchical nanostructures with variable morphologies were synthesized by controlled heating hydrated nanoparticles. The growth of nanostructures started with nanoparticles which formed loose aggregates. The nanoparticles within aggregates reorganized to form urchin-like structures which consisted of dense nanorods. With the growth of nanorods, regular microspheres were formed. At the same time, the nanorods coalesced to form wedge-like structures. The various surface subunits were just the outer display of wedge-like structures under different conditions. CuO nanostructures were gained by pyrolysis of malachite precursors. The attractive electrostatic force was responsible for aggregation of nanoparticles. During growth of aggregates, nanorods acted as growing tips which adsorbed adjacent nanoparticles. The Brownian motion was responsible for reorientation of nanoparticles to achieve low-energy configuration. Adsorbed water played an important role during formation of malachite nanostructures. The effect of growing environments on nanostructures was investigated. XRD, SEM, TEM and BET and so on were used to characterize the products.

One-step wet chemical method to Cu(OH)2 nanowires.

Under controlled temperature and pH of solution, Cu(OH)2 nanowires were successfully fabricated by dropping simply NaOH solution into CuSO4 solution. The morphology and composition of as-synthesized products were controllable by adjusting the pH value, reaction temperature and aging time. The influence of reaction conditions on the products was discussed in detail and optimum synthesis conditions were obtained. A mechanism of reconstruction involving dissolution, reprecipitation and transportation of [Cu(OH)4 ]2- was proposed. OH ions played an important role by absorbing on the surface of crystal planes which resulted in anisotropic growth of Cu(OH)2 crystals. This method with mild conditions was simple and repeatable. This route provides a new perspective to synthesize similar 1-D nanomaterials, such as Co(OH)2 and Ni(OH)2 and so on. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD) were used to characterize the products.

Bound 14C-metsulfuron-methyl residue in soils.

Bound residue(BR) of 14C-metsulfuron-methyl (14C-BR) in seven kinds of soil was significantly negative-related to soil pH and positive-related to the clay content during the initial 20 d of incubation, but only was significantly negative-related to soil pH after 30 d incubation. Again, the soil pH was found to be the dominant factor affecting BR formation from 14C-metsulfuron-methyl among the basic properties(soil pH, clay, OM and CEC etc.) of soil. The maximum content of 14C-BR in the 7 soils accounted for 19.3% - 52.6% of applied amount. In addition, the composition of the 14C-BR in fluvio marine yellow loamy (S7) at the 90 d of incubation was identified using the coupling technique of LC-MS and isotope tracing method. The results showed that the 14C-[2-amino-4-hydroxyl-6-methyl-1, 3, 5]-triazine, 14C-[2-amino-4-methoxy-6-methyl-1, 3, 5]-triazine and 14 C-metsulfuron-methyl parent compound constituted the main components of the BR derived from 14 C-metsulfuron-methyl in the S7. The relative percentage of the three compounds accounted for 41.4%, 35.8% and 19.3% of total recovery radioactivity, respectively. The results also indicated that a non-radioactive component, 2-methylformate-benzenesulfonyl-isocyanate, one of the degraded products of metsulfuron-methyl in soil, was also found to be one of the components of the BR. The parent compound in BR can well explain the phytotoxic effect on substitution crops caused by the BR derived from metsulfuron-methyl in soil.

Studies on bound (14)C-chlorsulfuron residues in soil.

The cause for phytotoxicity of bound residues of chlorsulfuron (2-chloro-N-[[4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino] carbonyl]benzenesulfonamide) to rotational crops is unknown. This study was conducted to determine the formation of nonextractable (bound) residues of chlorsulfuron in soil, and the distribution of bound residues in different organic matter fractions. The results showed that over 150 days, the extractable fraction of (14)C-residues decreased to 25.1% of applied chlorsulfuron, while bound residues concurrently increased to 47.1%. The distribution of (14)C-bound residues in soil organic matter fractions followed an order of humic acid (HA) < humin < fulvic acid (FA). Although the most bound residues were detected in the FA fraction, the amount associated with the humin fraction increased with time. After soil treatment by autoclaving, it was found that bound (14)C-chlorsulfuron residues became available again in the soil. One of the released products was 2-amino-4-hydroxyl-6-methyl-1,3,5-triazine (identified by GC-MS), which is a degradation product of chlorsulfuron.

Causes of phytotoxicity of metsulfuron-methyl bound residues in soil.

The bioavailability and phytotoxicity of bound residues of metsulfuron-methyl were studied using 14C-labeling and bioassay with oil rape (Brassica napus L.). Soil bound residues at the concentration of 0.27 and 0.53 nmol g(-1) resulted in significant inhibition of oil rape seedling growth. The biologically active component of the bound residues was identified to be metsulfuron-methyl parent compound. Other metabolites, including the hydrolysis product 2-methylformate-benzenesulfonamide, showed no toxicity to the test species. This study suggests that residues of metsulfuron-methyl bound previously to the soil matrix could be again released upon planting. The phytotoxicity of metsulfuron-methyl bound residues was mainly caused by the metsulfuron-methyl parent compound that became available during plant growth.

Identification of the bound residue composition derived from 14C-labeled chlorsulfuron in soil by using LC-MS and isotope tracing method.

A new method for extracting the bound residue(BR) derived from 14C-labeled chlorsulfuron in soils was developed, and the technique of combining LC-MS with isotope tracing method was subsequently applied to identify the composition of the 14C-BR in a loamy Fluvent derived from marine deposit. The results showed that the 14C-[2-amino-4-methoxyl-6-methyl-1,3,5]-triazine, 14C-[2-amino-4-hydroxyl-6-methyl-1,3,5]-triazine and 14C-chlorsulfuron parent compound constituted the main composition of the 14C-BR derived from 14C-labeled chlorsulfuron in the soil. The radioactive ratio of three compounds accounted for 39.8%, 35.4% and 17.9% of total recovered radioactivity, respectively. However, a small amount(3.6% of total recovered radioactivity) of the complex of 14C-[2-amino-4-hydroxyl-6-methyl-1,3,5]-triazine might have existed in the 14C-BR in association with an unknown soil substrate. 2-chlorobenzenesulfonamide was also detected to be one of the components of the BR. The results could well explain the mechanism of phytotoxicity caused by the BR derived from chlorsulfuron in soil. In addition, the mechanism of BR formation in soil was also discussed in details.

Bioavailability of bound residue derived from 14C-labeled chlorsulfuron in soil and its mechanism of phytotoxicity.

The bioavailability of bound residue (BR) derived from 14C-labeled chlorsulfuron in soil and effect of the main components of the BR on growth of rape (brassica napus) and rice (Oryza sativa L.) were investigated. The results showed that the BR with the concentration of 0.28 and 0.56 nmol/g air-dried soil, which was calculated by special radioactivity of 14C-labeled chlorsulfuron parent compound, resulted in significant depression effect on growth of rape seedling. It was assured that the main components (2-amino-4-methoxyl-6-methyl-1,3,5-triazine, 2-amino-4-hydroxyl-6-methyl-1,3,5-triazine, and 2-chloro-benzenesul-fonamide) of the BR did not inhibit the growth of rape and rice. LC-MS analysis demonstrated that the parent compound previously bound to the soil matrix could be again released and transformed into methanol-extractable residue during the course of rape growth. It was concluded that the molecular leading to the phytotoxicity to rape and rice in the BR is still the parent compound.

Fabrication of multilayer pancakelike basic magnesium carbonate.

The properties of nanomaterials was strongly affected by their microstructures. Here Mg5(CO3)4(OH)2 x 4H2O multilayer pancakelike structures were fabricated successfully by reaction of MgCl2 and Na2CO3 in aqueous solution at 363 K. The growth process of nanostructures was observed by XRD and SEM. Several transition states of multilayer pancakelike basic magnesium carbonates were observed, which help to understand better the formation process of this hierarchical nanostructures. The formation mechanism of Mg5(CO3)4(OH)2 x 4H2O multilayer pancakelike structures was discussed and helical growth was proposed. The amorphous nanoparticles were formed firstly. Then nanopartilces aggregated and oriented assembly under the direction of chemical bonds with the help of water molecules. The multilayer pancakelike basic magnesium carbonates was formed by helical growth of wafers along (100) and (001) direction. The diameter and volume decreased with the increasing concentration of reactants.

Preparation and luminescence properties of lanthanide (Eu3+, Sm3+) complexes and their hectorite-based composites.

The complexes of europium and samarium with phthalates ligands were synthesized and characterized. The luminescence behaviors of the lanthanide complexes as well as their hectorite-based composites were investigated by fluorescence spectra. The results indicated that the lanthanide complexes showed slightly lower intensities in hectorite matrix than that of corresponding pure complexes. The lanthanide ion relative fluorescence intensity (LRFI) was enhanced when the lanthanide complexes were doped into hectorite.

Equilibrium models and kinetic for the adsorption of methylene blue on Co-hectorites.

The adsorption of methylene blue (MB) onto the surface of cobalt doping hectorite (Co-hectorite) was systematically studied. The physical properties of Co-hectorites were investigated, where characterizations were carried out by X-ray diffraction (XRD) and Electron Diffraction Spectrum (EDS) techniques, and morphology was examined by nitrogen adsorption. The sample with a Co content 5% (m/m) had a higher specific surface area than other Co-hectorites. The pore diameters were distributed between 2.5 and 5.0 nm. The adsorption results revealed that Co-hectorite surfaces possessed effective interactions with MB and bases, and greatest adsorption capacity achieved with Co content 5%, where the best-fit isotherm model was the Langmuir adsorption model. Kinetic studies were fitted to the pseudo-second-order kinetic model. The intraparticle diffusion was not the rate-limiting step for the whole reaction.

[14C-extractable residue, C-bound residue and mineralization of 14C-labeled metsulfuron-methyl in soils].

The purpose of the present study was to investigate 14C-extractable residue(14C-ER), 14C-bound residue(14C-BR) and mineralization of 14C-labeled metsulfuron-methyl in soils. The main factors affecting 14C-BR formation and the distribution pattern of 14C-BR in humus were also discussed in details. The results were as follows: (1) The total 14C-ER content of 14C-metsulfuron-methyl in seven kinds of soil was positively related to soil pH and negatively related to clay content significantly during the initial 20 days of incubation, however, only positively relation to soil pH was found after 30 days of incubation. Moreover, the half-life values of 14C-metsulfuron-methyl parent compound derived from 14C-ER in soils tested ranged from 13.3 to 66.6 days. The degradation rate coefficient lambda (day-1) was negatively related to soil pH. (2) The 14C-BR content of 14C-metsulfuron-methyl in soils was significantly negatively related to soil pH and positively related to the clay content during the initial 20 days of incubation, but only was significantly negatively related to soil pH after 30 days incubation. Again, the soil pH was found to be the dominant factor affecting BR formation of 14C-metsulfuron-methyl among the basic properties of soil. The maximum content of 14C-BR of 14C-metsulfuron-methyl in the soils accounted for 19.3%-52.6% of applied amount. (3) During the whole periods of the incubation, the 14C-BR of 14C-metsulfuron-methyl in the soils was found to be mainly associated with fulvic acid and humin. The relative percentage of 14C-BR in fulvic acid was higher than in humin, while the content of the 14C-BR distributed in humic acid only account for less than 1% of applied amount. Therefore, fulvic acid played an important role in the process of BR formation of 14C-metsulfuron-methyl. (4) About 12.9%-27.0% of applied amount of 14C-metsulfuron-methyl was mineralized to 14CO2 through opening 14C-triazine ring in soils tested after 180 days of the incubation. It was difficult for 14C-metsulfuron-methyl to mineralize to 14CO2 in an alkaline soil.