Effect of pre-hospital early intervention combined with an in-hospital emergency model in the emergency care of patients with acute stroke.

OBJECTIVE: This study aimed to explore the effect of pre-hospital early intervention combined with an in-hospital emergency model in the emergency care of patients with acute stroke. METHODS: Eighty-six patients with acute stroke treated in our hospital between December 2018 and January 2020 were enrolled prospectively and were divided into two groups according to the random number table method, with 43 cases in each group. The control group received conventional emergency mode care, while the study group received pre-hospital early intervention combined with an in-hospital emergency model. The success rate of successful resuscitation (CPR), resuscitation endpoints, complication rates, nursing satisfaction and changes in limb motor function (Fugl-Meyer score) and activity of daily living (ADL score) before and at 3 months after intervention were compared between the two groups. RESULTS: The total success rate of rescue and nursing satisfaction were higher in the study group (93.02%, 97.77%) than in the control group (74.42%, 79.07%), while the complication rate in the study group (4.65%) was lower than that in the control group (20.93%). Time to resuscitation, time to thrombolytic therapy, time from admission to completion of imaging, and the length of hospital stay were shorter in the study group than in the control group (P<0.05). Compared with pre-intervention, Fugl-Meyer and ADL scores were increased in both groups and were higher in the study group (P<0.05). CONCLUSION: Pre-hospital early intervention combined with in-hospital emergency model in the first aid of patients with acute stroke can effectively improve the success rate of rescue, shorten the duration of rescue and length of hospital stay, reduce the incidence of complications, increase nursing satisfaction, and improve limb motor function and ADL.

Spacer effect on nanostructures and self-assembly in organogels via some bolaform cholesteryl imide derivatives with different spacers.

In this paper, new bolaform cholesteryl imide derivatives with different spacers were designed and synthesized. Their gelation behaviors in 23 solvents were investigated, and some of them were found to be low molecular mass organic gelators. The experimental results indicated that these as-formed organogels can be regulated by changing the flexible/rigid segments in spacers and organic solvents. Suitable combination of flexible/rigid segments in molecular spacers in the present cholesteryl gelators is favorable for the gelation of organic solvents. Scanning electron microscopy and atomic force microscopy observations revealed that the gelator molecules self-assemble into different aggregates, from wrinkle and belt to fiber with the change of spacers and solvents. Spectral studies indicated that there existed different H-bond formations between imide groups and assembly modes, depending on the substituent spacers in molecular skeletons. The present work may give some insight into the design and character of new organogelators and soft materials with special molecular structures.

Self-Assembly and Nanostructures in Organogels Based on a Bolaform Cholesteryl Imide Compound with Conjugated Aromatic Spacer.

The self-assembly of small functional molecules into supramolecular structures is a powerful approach toward the development of new nanoscale materials and devices. As a class of self-assembled materials, low weight molecular organic gelators, organized in special nanoarchitectures through specific non-covalent interactions, has become one of the hot topics in soft matter research due to their scientific values and many potential applications. Here, a bolaform cholesteryl imide compound with conjugated aromatic spacer was designed and synthesized. The gelation behaviors in 23 solvents were investigated as efficient low-molecular-mass organic gelator. The experimental results indicated that the morphologies and assembly modes of as-formed organogels can be regulated by changing the kinds of organic solvents. Scanning electron microscopy and atomic force microscopy observations revealed that the gelator molecule self-assemble into different aggregates, from wrinkle and belt to fiber with the change of solvents. Spectral studies indicated that there existed different H-bond formations between imide groups and assembly modes. Finally, some rational assembly modes in organogels were proposed and discussed. The present work may give some insight to the design and character of new organogelators and soft materials with special structures.

Mechanism of Cd2+ on DNA cleavage and Ca2+ on DNA repair in liver of silver crucian carp.

The subject of acute injury, apoptosis and canceration of animals induced by heavy metal ions has been one of the hotspots studied worldwide. However, the exact molecular mechanism of Cd-induced carcinogenicity remains largely unclear, and how to relieve the toxicity in vivo has rarely been reported. For this paper, we have investigated the mechanism of Cd2+ on DNA cleavage and Ca2+ on DNA repair in the liver of silver crucian carp (Carassius auratus gibelio) by agarose gel electrophoresis methods and by estimating biochemical indexes. Our results show that Cd2+ induces the classical laddering degradation of DNA in vivo and that DNA cleavage is repaired after injection with Ca2+ under various Cd2+ concentrations. DNA cleavage caused by Cd2+ is due to the activation of deoxyribonuclease (DNase) and the accumulation of reactive oxygen species (ROS). Furthermore, Cd2+ destroys the antioxidant system, which diminishes the activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), causing an increase of the lipid peroxidation (LPO) level, respectively. However, after the liver is injected with Ca2+ under various Cd2+ concentrations, the DNase activity, the ROS generating rate and the LPO level are obviously reduced, the activities of SOD, CAT, and POD are greatly increased. At the same time, ROS production and removal recoves its balance. The results show that Ca2+ can relieve the toxicity of Cd2+ in silver crucian carp.

Was improvement of spinach growth by nano-TiO(2) treatment related to the changes of Rubisco activase?

Characterized by a photo-catalysis property, nano-anatase TiO(2) is closely related to photosynthesis of spinach. It could not only improve light absorbance, transformation from light energy to electron energy and active chemical energy, but also promote the activity of Rubiso activase of spinach. However, the relation between the activity of Rubiso activase and the growth of spinach promoted by nano-anatase TiO(2) treatment remains largely unclear. In this study, we find that the amount and the activity of Rubiso activase are obviously increased by nano-anatase TiO(2 )treatment, which led to the great promotion of Rubsico carboxylation and the high rate of photosynthesis, thus improving of spinach growth. The significant enhancement of Rubiso activase activity of nano-anatase TiO(2 )treated spinach is also accompanied by conformational changes as determined by spectroscopic analysis. But bulk TiO(2) effect is not as significant as nano-anatase TiO(2), as the grain size of nano-anatase TiO(2) (5 nm) is much smaller than that of bulk TiO(2), which entered spinach cell more easily.

Effects of Pb2+ on energy distribution and photochemical activity of spinach chloroplast.

Lead (Pb(2+)) is a well-known highly toxic element. The mechanisms of the Pb(2+) toxicity are not well understood for photosynthesis. In this paper, we reported the effect of Pb(2+) on light absorption, distribution and conversion of spinach chloroplast by spectroscopy, and photochemical reaction activities. Several effects of Pb(2+) were observed: (1) the absorption peak intensity of chloroplast obviously decreased in red and blue region and produced optical flattering; (2) fluorescence quantum yield nearby 680 nm of chloroplast greatly declined; (3) the excitation band nearby 440 nm of chloroplast significantly descended; (4) Pb(2+) treatments reduced of the rate of whole chain electron transport, photochemical activities of PSII DCPIP photoreduction and oxygen evolution, but the photoreduction activities of PSI were little changed. Together, the studies of the experiments showed that Pb(2+) decreased absorption of light on spinach chloroplast and inhibited excitation energy to be absorbed by LHCII and transferred to PSII, then reduced the conversion from light energy to electron energy, and decelerated electron transport, water photolysis and oxygen evolution.

The improvement of spinach growth by nano-anatase TiO2 treatment is related to nitrogen photoreduction.

The improvement of spinach growth is proved to relate to N2 fixation by nano-anatase TiO2 in this study. The results show that all spinach leaves kept green by nano-anatase TiO2 treatment and all old leaves of control turned yellow white under culture with N-deficient solution. And the fresh weight, dry weight, and contents of total nitrogen, NH4(+), chlorophyll, and protein of spinach by nano-anatase TiO2 treatment presented obvious enhancement compared with control. Whereas the improvements of yield of spinach were not as good as nano-anatase TiO2 treatment under N-deficient condition, confirming that nano-anatase TiO2 on exposure to sunlight could chemisorb N2 directly or reduce N2 to NH3 in the spinach leaves, transforming into organic nitrogen and improving the growth of spinach. Bulk TiO2 effect, however, was not as significant as nano-anatase TiO2. A possible metabolism of the function of nano-anatase TiO2 reducing N2 to NH3 was discussed.

Effects of nano-anatase TiO2 on absorption, distribution of light, and photoreduction activities of chloroplast membrane of spinach.

The effects of nano-anatase TiO2 on light absorption, distribution, and conversion, and photoreduction activities of spinach chloroplast were studied by spectroscopy. Several effects of nano-anatase TiO2 were observed: (1) the absorption peak intensity of the chloroplast was obviously increased in red and blue region, the ratio of the Soret band and Q band was higher than that of the control; (2) the great enhancement of fluorescence quantum yield near 680 nm of the chloroplast was observed, the quantum yield under excitation wavelength of 480 nm was higher than the excitation wavelength of 440 nm; (3) the excitation peak intensity near 440 and 480 nm of the chloroplast significantly rose under emission wavelength of 680 nm, and F 480 / F 440 ratio was reduced; (4) when emission wavelength was at 720 nm, the excitation peaks near 650 and 680 nm were obviously raised, and F 650 / F 680 ratio rose; (5) the rate of whole chain electron transport, photochemical activities of PSII DCPIP photoreduction and oxygen evolution were greatly improved, but the photoreduction activities of PSI were a little changed. Together, the studies of the experiments showed that nano-anatase TiO2 could increase absorption of light on spinach chloroplast and promote excitation energy to be absorbed by LHCII and transferred to PSII and improve excitation energy from PSI to be transferred to PSII, thus, promote the conversion from light energy to electron energy and accelerate electron transport, water photolysis, and oxygen evolution.

Direct evidence for interaction between lead ions and kidney DNA from silver crucian carp.

A direct interaction of lead (Pb) with kidney DNA from silver crucian carp (Carassius auratus gibelio) has been systematically studied in vitro using multi-techniques, including UV-vis absorption, extended X-ray absorption fine structure, vacuum ultraviolet circular dichroism spectral methods and gel electrophoresis. We find that Pb is bound with four oxygen or nitrogen atoms of DNA in its fresh shell at the distances of 2.64 A. Additionally, Pb may bind to the oxygen atom of nucleic acid or nitrogen atom of base pairs of DNA in that obvious changes in the secondary structure of DNA are found after Pb treatment. However, this direct interaction of Pb with DNA do not cause DNA cleavage in vitro.

Regulative mechanism of Ce3+ relieves DNA damage caused by Cd2+ in the kidney of silver crucian carp.

The mechanism of Cd2+ on the DNA cleavage and Ce3+ on the DNA repair in the kidney of silver crucian carp (Carassius auratus gibelio) is investigated by agarose gel electrophoresis methods and assaying biochemical indexes. It proves that Cd2+ induces the classical laddering degradation of DNA in vivo, but DNA cleavage is repaired after injecting with a low Ce3+ concentration under various Cd2+ concentrations. The DNA cleavage caused by Cd2+ is the result of the activation of deoxyribonuclease (DNase) and accumulation of reactive oxygen species (ROS), and Cd2+ destroys the antioxidant system, which diminishes the activities of superoxide dismutase, catalase, and peroxidase, and the increase of the lipid peroxidation (LPO) level. However, Ce3+ could inhibit activation of Cd2+ on DNase activity, relieve inhibition of Cd2+ on activities of the antioxidant enzyme, and diminish ROS accumulation. The results show that Ce3+ could relieve the toxicity of Cd2+ to silver crucian carp.

Mechanism of nano-anatase TiO2 on promoting photosynthetic carbon reaction of spinach: inducing complex of rubisco-rubisco activase.

Having a photocatalyzed characteristic, our previous research had proved that nano-anatase TiO2 is closely related to the photosynthesis of spinach. It could not only improve the light absorbance and the transformation from light energy to electron energy and to active chemical energy but also promote carbon dioxide (CO2) assimilation of spinach. However, the mechanism of carbon reaction promoted by nano-anatase TiO2 remains largely unclear. By electrophoresis and Western blot methods, the results of the experiments proved that Rubisco from the nano-anatase TiO2-treated spinach during the extraction procedure of Rubisco was found to consist of Rubisco and a heavier molecular-mass protein (about 1,200 kDa) comprising both Rubisco and Rubisco activase. The Rubisco carboxylase activity was 2.67 times that of Rubisco from the control and it could hydrolyze ATP in the same manner as Rubisco activase. The total sulfhydryl groups and available sulfhydryl groups of the Rubisco were 32 -SH and 21 -SH per mole of enzyme more than those of the Rubisco purified from the control, respectively. The circular dichroism spectra showed that the secondary structure of Rubisco from the nano-anatase TiO2-treated spinach was very different from Rubisco of the control. It suggested that the mechanism of nano-anatase TiO2 activating Rubisco of spinach was that the complex of Rubsico and Rubisco activase was induced in spinach, which promoted Rubsico carboxylation and increased the rate of photosynthetic carbon reaction.

Influences of nano-anatase TiO2 on the nitrogen metabolism of growing spinach.

Previous research showed that nano-TiO2 could significantly promote photosynthesis and greatly improve growth of spinach, but we also speculated that an increase of spinach growth by nano-TiO2 treatment might be closely related to the change of nitrogen metabolism. The effects of nanoanatase TiO2 on the nitrogen metabolism of growing spinach were studied by treating them with nano-anatase TiO2. The results showed that nano-anatase TiO2 treatment could obviously increase the activities of nitrate reductase, glutamate dehydrogenase, glutamine synthase, and glutamic-pyruvic transaminase during the growing stage. Nano-anatase TiO2 treatment could also promote spinach to absorb nitrate, accelerate inorganic nitrogen (such as NO3--N and NH4+-N) to be translated into organic nitrogen (such as protein and chlorophyll), and enhance the fresh weight and dry weights.

Interaction mechanism between Cd2+ ions and DNA from the kidney of the silver crucian carp.

Cadmium is one of the most toxic heavy metals and is known to accumulate in freshwater food chains. The underlying mechanism for its genotoxicity has not been investigated for any freshwater fish. It has, however, been suggested that cadmium-induced carcinogenesis might involve either direct or indirect interaction of Cd2+ with DNA. The interaction between Cd2+ and DNA from the kidney of the silver crucian carp (Carassius auratus gibelio) in vitro and in vivo is investigated by spectrophotometric methods and agarose gel electrophoresis methods. Cd2+ could insert into DNA basepairs, bind to nucleic acid, and result in notable hypochromicities. The analysis of agarose gel electrophoresis proves that Cd2+ at different concentrations does not cause DNA cleavage in vitro; however, kidneys display the classical laddering degradation of DNA in vivo, which is the result of the promotion of deoxyribonuclease activity or inhibition of superoxide dismutase and catalyse activity and the accumulation of reactive oxygen species caused by Cd2+ ions in vivo.

Effect of Nd3+ ion on carboxylation activity of ribulose-1,5-bisphosphate carboxylase/oxygenase of spinach.

Neodymium (Nd), as a member of rare earth elements, proved to enhance the photosynthesis rate and organic substance accumulation of spinach through the increase in carboxylation activity of Rubisco. Although the oxygenase activity of spinach Rubisco was slightly changed with the Nd(3+) treatment, the specific factor of Rubisco was greatly increased. It was partially due to the promotion of Rubisco activase (R-A) activity but mainly to the formation of Rubisco-Rubisco activase super-complex, a heavier molecular mass protein (about 1200kD) comprising both Rubisco and Rubisco activase. This super-complex was found during the extraction procedure of Rubisco by the gel electrophoresis and Western-blot studies. The formation of Rubisco-R-A super-complex suggested that the secondary structure of the protein purified from the Nd(3+)-treated spinach was different from that of the control. Extended X-ray absorption fine structure study of the 'Rubisco' purified from the Nd(3+)-treated spinach revealed that Nd was bound with four oxygen atoms and two sulfur atoms of amino acid residues at the Nd-O and Nd-S bond lengths of 2.46 and 2.89A, respectively.