Endovascular thrombectomy in wake-up stroke guided by arterial spin-labeling and fluid-attenuated inversion recovery versus diffusion-weighted imaging mismatch on MRI.

OBJECTIVE: This purpose of this study is to investigate the effectiveness and safety of utilizing the arterial spin-labeling (ASL) combined with diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) combined with DWI double mismatch in the endovascular treatment of patients diagnosed with wake-up stroke (WUS). METHODS: In this single-center trial, patients diagnosed with WUS underwent thrombectomy if acute ischemic lesions were observed on DWI indicating large precerebral circulation occlusion. Patients with no significant parenchymal hypersignal on FLAIR and ASL imaging showing a hypoperfusion tissue to infarct core volume ratio of at least 1.2 were included. The participants were divided into groups receiving endovascular thrombectomy plus medical therapy or medical therapy alone, based on their subjective preference. Functional outcomes were assessed using the ordinal score on the modified Rankin scale (mRs) at 90 days, along with the rate of functional independence. RESULTS: In this study, a total of 77 patients were included, comprising 38 patients in the endovascular therapy group and 39 patients in the medical therapy group. The endovascular therapy group exhibited more favorable changes in the distribution of functional prognosis measured by mRs at 90 days, compared to the medical therapy group (adjusted common odds ratio, 3.25; 95% CI, 1.03 to 10.26; P < 0.01). Additionally, the endovascular therapy group had a higher proportion of patients achieving functional independence (odds ratio, 4.0; 95% CI, 1.36 to 11.81; P < 0.01). Importantly, there were no significant differences observed in the incidence of intracranial hemorrhage or mortality rates between the two groups. CONCLUSION: Guided by the ASL-DWI and FLAIR-DWI double mismatch, endovascular thrombectomy combined with standard medical treatment appears to yield superior functional outcomes in patients with WUS and large vessel occlusion compared to standard medical treatment alone.

China Trends in Physical Inactivity from 2013 to 2019: An Analysis of 4.23 Million Participants.

INTRODUCTION: This study aimed to evaluate recent trends in physical inactivity prevalence by sociodemographic characteristics and the province of China's residence between 2013 and 2019. METHODS: The study included 4,229,616 participants 40 yr or older from 414 geographically defined localities in China during the 7-yr period. Self-reported total physical inactivity was collected to determine the standardized prevalence of physical inactivity. Logistic regression analysis was used to examine the association between physical inactivity and stroke risk, obtaining odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Results showed that the standardized prevalence of physical inactivity increased from 22.12% (95% CI = 21.99%-22.45%) in 2013 to 28.79% (95% CI = 28.48%-29.19%) in 2019, with an absolute difference of 6.67% (95% CI = 6.15% to 7.16%) and a yearly increase rate of 5.03% (95% CI = 4.85% to 5.21%). In 2019, physical inactivity was higher in female and rural participants (female = 29.55%, rural = 29.46%) than in male and urban participants (male = 28.03%, urban = 28.26%). The prevalence of physical inactivity also varied by race/ethnic groups, with the highest prevalence observed among Uyghur (47.21%) and the lowest among Yizu (14.84%). Additionally, the prevalence of physical inactivity differed by province, ranging from 14.44% in Beijing to 50.09% in Tianjin in 2019. Multivariate analyses showed that physical inactivity was associated with a higher risk of stroke (OR = 1.17, 95% CI = 1.12-1.21, P < 0.001). CONCLUSIONS: In conclusion, our study found an overall increase in physical inactivity prevalence among Chinese adults ≥40 yr old from 2013 to 2019, with significant variation across regions, sex, ages, and race/ethnic groups.

Direct ab initio study on the rate constants of radical C2(A 3Π(u)) + C3H8 reaction.

The mechanism and kinetics of the radical (3)C(2) + C(3)H(8) reaction have been investigated theoretically by direct ab initio kinetics over a wide temperature range. The potential energy surfaces have been constructed at the CCSD(T)/B3//UMP2/B1 levels of theory. The electron transfer was also analyzed by quasi-restricted orbital (QRO) in detail. It was shown that all these channels proceed exclusively via hydrogen abstraction. The overall ICVT/SCT rate constants are in agreement with the available experimental results. The prediction shows that the secondary hydrogen of C(3)H(8) abstraction by (3)C(2) radical is the major pathway at low temperatures (below 700 K), while as the temperature increases, the primary hydrogen of C(3)H(8) abstraction becomes more important and more favorable. A negative temperature dependence of the rate constants for the reaction of (3)C(2) + C(3)H(8) was observed. The three-(k (3)) and four-parameter (k (4)) rate-temperature expressions were also provided within 243-2000 K to facilitate future experimental studies.

Large Density-Functional and Basis-Set Effects for the DMSO Reductase Catalyzed Oxo-Transfer Reaction.

The oxygen-atom transfer reaction catalyzed by the mononuclear molybdenum enzyme dimethyl sulfoxide reductase (DMSOR) has attracted considerable attention through both experimental and theoretical studies. We show here that this reaction is more sensitive to details of quantum mechanical calculations than what has previously been appreciated. Basis sets of at least triple-ζ quality are needed to obtain qualitatively correct results. Dispersion has an appreciable effect on the reaction, in particular the binding of the substrate or the dissociation of the product (up to 34 kJ/mol). Polar and nonpolar solvation effects are also significant, especially if the enzyme can avoid cavitation effects by using a preformed active-site cavity. Relativistic effects are considerable (up to 22 kJ/mol), but they are reasonably well treated by a relativistic effective core potential. Various density-functional methods give widely different results for the activation and reaction energy (differences of over 100 kJ/mol), mainly reflecting the amount of exact exchange in the functional, owing to the oxidation of Mo from +IV to +VI. By calibration toward local CCSD(T0) calculations, we show that none of eight tested functionals (TPSS, BP86, BLYP, B97-D, TPSSH, B3LYP, PBE0, and BHLYP) give accurate energies for all states in the reaction. Instead, B3LYP gives the best activation barrier, whereas pure functionals give more accurate energies for the other states. Our best results indicate that the enzyme follows a two-step associative reaction mechanism with an overall activation enthalpy of 63 kJ/mol, which is in excellent agreement with the experimental results.

Mechanism insights of ethane C-H bond activations by bare [Fe(III)═O]+: explicit electronic structure analysis.

Alkane C-H bond activation by various catalysts and enzymes has attracted considerable attention recently, but many issues are still unanswered. The conversion of ethane to ethanol and ethene by bare [Fe(III)═O](+) has been explored using density functional theory and coupled-cluster method comprehensively. Two possible reaction mechanisms are available for the entire reaction, the direct H-abstraction mechanism and the concerted mechanism. First, in the direct H-abstraction mechanism, a direct H-abstraction is encountered in the initial step, going through a collinear transition state C···H···O-Fe and then leading to the generation of an intermediate Fe-OH bound to the alkyl radical weakly. The final product of the direct H-abstraction mechanism is ethanol, which is produced by the hydroxyl group back transfer to the carbon radical. Second, in the concerted reaction mechanism, the H-abstraction process is characterized via overcoming four/five-centered transition states (6/4)TSH_c5 or (4)TSH_c4. The second step of the concerted mechanism can lead to either product ethanol or ethene. Moreover, the major product ethene can be obtained through two different pathways, the one-step pathway and the stepwise pathway. It is the first report that the former pathway starting from (6/4)IM_c to the product can be better described as a proton-coupled electron transfer (PCET). It plays an important role in the product ethene generation according to the CCSD(T) results. The spin-orbital coupling (SOC) calculations demonstrate that the title reaction should proceed via a two-state reactivity (TSR) pattern and that the spin-forbidden transition could slightly lower the rate-determining energy barrier height. This thorough theoretical study, especially the explicit electronic structure analysis, may provide important clues for understanding and studying the C-H bond activation promoted by iron-based artificial catalysts.

Mechanism of benzene hydroxylation by high-valent bare Fe(IV)=O2+: explicit electronic structure analysis.

The conversion of benzene to phenol by high-valent bare FeO(2+) was comprehensively explored using a density functional theory method. The conductor-like screen model (COSMO) was used to mimic the role of solvent effect with acetonitrile chosen as the solvent. Two radical mechanisms and one oxygen insertion mechanism were tested for this conversion. The first radical mechanism can also be named as the concerted mechanism in which the hydrogen-atom abstraction process is accomplished via a four-centered transition state. The second radical mechanism is initiated by a direct hydrogen-atom abstraction with a collinear C-H-O transition structure. It is actually the same as the well-accepted rebound mechanism for the C-H bond activation by heme and nonheme iron-oxo catalysts. The third is an oxygen insertion mechanism which is essentially an aromatic electrophilic attack leading to an arenium σ-complex intermediate. The formation of a precomplex with an η(4) coordinate environment in the first radical mechanism is energetically more favorable. However, the relatively lower activation energy barrier of the oxygen insertion mechanism compared to the radical ones makes it highly competitive if the Fe=O(2+) collides with benzene in the proper orientation. The detailed potential energy surfaces also indicate that the second radical mechanism, i.e., the benzene C-H bond activation through the rebound mechanism, is less favorable. This thorough theoretical study, especially the electronic structure analysis, may offer very important clues for understanding and studying C-H bond activation by iron-based catalysts and enzymatic reactions in protein active pockets.

[Establishment of cellular immunity of enhanced hepatitis B vaccine].

OBJECTIVE: To establish the method to detect the cellular immune response of enhanced hepatitis B vaccine and make verification preliminary. METHODS: Immunized BALB/c mice with enhanced hepatitis B vaccine and detected the IFN-gamma spots forming cells (SFC) of mouse spleen cell by Elispot. Optimized the conditions of the experiment. Cellular immune response between enhanced hepatitis B vaccine and normal hepatitis B vaccine by Elispot were compared. RESULTS: IFN-gamma SFC was higher in 5microg dose than in 2microg dose after immunization with enhanced hepatitis B vaccine and IFN-gamma SFC was declined after immunization 3 weeks ago. IFN-gamma SFC was higher in stimulus by peptide than by protein. Compared to normal hepatitis B vaccine, IFN-gamma SFC was higher in enhanced hepatitis B vaccine. CONCLUSION: Established the detection method to evaluate the cellular immunity of enhanced hepatitis B vaccine and tested the repeatability.

Direct ab initio dynamics study of radical C4H (X̃2Σ+) + CH4 reaction.

The methane (CH(4)) hydrogen abstraction reaction by linear butadiynyl radical C(4)H (CCCCH) has been investigated by direct ab initio dynamics over a wide temperature range of 100-3000 K, theoretically. The potential energy surfaces (PESs) have been constructed at the CCSD(T)/aug-cc-pVTZ//BB1K/6-311G(d,p) levels of theory. Two different hydrogen abstraction channels by C(1) and C(4) of C(4)H (C(1)C(2)C(3)C(4)H) have been considered. The results indicate that the C(1) position of C(4)H is a more reactive site. The electron transfer behaviors of two possible channels are also analyzed by quasi-restricted orbital (QRO) in detail. The rate constants calculated by canonical variational transition-state theory (CVT) with the small-curvature tunneling correction (SCT) are in excellent agreement with available experimental values. The normal and three-parameter expressions of Arrhenius rate constants are also provided within 100-3000 K. It is expected to be helpful for further studies on the reaction dynamics behaviors over a wide temperature range where no experimental data is available so far.

Conformational transition pathway in the allosteric process of calcium-induced recoverin: molecular dynamics simulations.

Recoverin is an important neuronal calcium sensor (NCS) protein, which have been implicated in a wide range of Ca(2+) signaling events in neurons and photoreceptors. To characterize the conformational transition of recoverin from the myristoyl sequestered state to the extrusion state, a series of conventional molecular dynamics (CMD) and targeted molecular dynamics (TMD) simulations were performed. The 36.8 ns long CMD and TMD simulations on recoverin revealed a reliably conformational transition pathway, which can be viewed as a sequential two-stage process. A very important mechanistic conclusion from the present TMD simulations is that the hydrophobic and hydrophilic interactions modulate the allostery cooperatively in the conformational transition pathway. In the first stage, three salt-bridges broken between Lys-84 and Gly-124, between Lys-5 and Glu-103 and between Gly-16 and Lys-97 are major components to destabilize the structure of state T and trigger the swivel of the N- and C-terminal domains. In the second stage, the rupture of H-bond Phe-56-O(...)H(O)-Thr-21 leads to the two helices of EF-1 apart from each other, destabilizing the hydrophobic interactions of the myristoyl group with its environment, whereas the making of H-bond Leu-108-O(...)H(O)-Ser-72 helps the interfacial domain maintain its structural integrity during the course of the myristoyl extrusion. The molecular dynamics simulations results are beneficial to understanding the mechanism of how and why NCS proteins make progress in the photo-signal transduction processes. Further experimental and theoretical studies are still very desirable.

Theoretical elucidation of the rhodium-catalyzed [4 + 2] annulation reactions.

The reaction mechanism of the Rh-catalyzed [4 + 2] annulation of 4-alkynals with isocyanates is unraveled using density functional calculations. The reaction mechanisms of the model system and the real substituted system have been investigated and the results are compared. From our theoretical results based on the model and real substituted system, it is shown that (a) the rate-determining step is the Rh-H addition to the alkyne, (b) the formation of the cyclopentenone G and glutarimide K represents a severe competition, and (c) the product selectivity should be controlled by the amount of the isocyanates. In addition, it is demonstrated that there exist steric effects in the real substituted system, but missed in model system. Our calculations also show that although the results obtained on the model system could explain the mechanism in principle, the real substituted system could reflect the mechanism more exactly and make the reaction proceed with regioselectivity.

A Barrier-Free Atomic Radical-Molecule Reaction: F + Propene.

The possible reaction mechanism of atomic radical F with propene is investigated theoretically by a detailed potential energy surface (PES) calculation at the UMP2/6-311++G(d,p) and CCSD(T)/cc-pVTZ (single-point) levels using ab initio quantum chemistry methods and transition-state theory. Various possible reaction paths including addition-isomerization-elimination reactions and direct H-atom abstraction reactions are considered. Among them, the most feasible pathway should be the atomic radical F ((2)F) attacking on the C [Formula: see text] C double bond in propene (CH3CH [Formula: see text] CH2) to form a weakly bound complex I1 with no barrier, followed by atomic radical F addition to the C [Formula: see text] C double bond to form the low-lying intermediate isomer 3 barrierlessly. Starting from intermediate isomer 3, the most competitive reaction pathway is the dissociation of the C2-C3 single bond via transition state TS3-P5, leading to the product P5, CH3 + CHF [Formula: see text] CH2. However, in the direct H-atom abstraction reactions, the atomic radical F picking up the b-allylic hydrogen of propene barrierlessly is the most feasible pathway from thermodynamic consideration. The other reaction pathways on the doublet PES are less competitive because of thermodynamical or kinetic factors. No addition-elimination mechanism exists on the potential energy surface. Because the intermediates and transition states involved in the major pathways are all lower than the reactants in energy, the title reaction is expected to be rapid. Furthermore, on the basis of the analysis of the kinetics of all channels through which the addition and abstraction reactions proceed, we expect that the competitive power of reaction channels may vary with experimental conditions for the title reaction. The present study may be helpful for probing the mechanisms of the title reaction and understanding the halogen chemistry.

Effects of gentiopicrooside injections on experimental hepatic injury.

OBJECTIVE: To investigate the protective and jaundice-relieving effects of gentiopicrooside (GPS) injections in mouse and rat models of chemical-induced and immune-mediated hepatic injury. METHODS: Mouse models of chemical-induced liver injury were established by CCl4 injections into the abdominal cavity, mouse models of immune-mediated liver damage by bacillus Calmette-Guerin (BCG) and lipopolysaccharide (LPS) and rat models of jaundice by oral alpha-naphthyliso-thiocyanate (ANIT). Treatment with GPS injections was administered and both of enzyme activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the Serum were measured in the models. The serum level of total bilirubin was determined in the jaundice models. RESULTS: Compared with those of the untreated models, the enzyme activities of ALT and AST were significantly reduced in groups with a 10 day GPS treatment (P<0.001, P<0.05). Higher dosage of GPS showed more conspicuous effects in relieving the jaundice. CONCLUSION: GPS can be administered as the antagonist against CC14-induced liver injury and offers protection against immune-mediated liver damage.