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An inverse sandwich structure has been computationally predicted for uranium boride and extended to the series of actinide elements (An) from Th to Cm. The electronic structure and chemical bonding of these novel compounds have been analyzed using density functional theory and multireference wave-function based methods. We report the trends in electronic structure and bonding for An2B8, and found that (d-π)π and (d-p)δ are the most important factors in the stability of An2B8. The (f-p)δ bond provides extra stabilization for Pa2B8 and U2B8, owing to the extensive interactions of An-B8-An, resulting in a short distance for the Pa-Pa and U-U bonds.
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This research aimed to clarify the effects of exogenously applied chitosan on the physiological characteristics, antioxidant activities, and Cd accumulation of wheat (Triticum aestivum L.) seedlings under cadmium (Cd) stress and to identify the key indicators based on the partial least squares model. The wheat variety studied was Bainong207 (BN207), and Cd-stress was achieved by growing seedlings in a hydroponic culture experiment with 10 and 25 µmol·L-1 Cd2+ added to the culture solution. It was found that both Cd-stress at 10 and 25 µmol·L-1 significantly inhibited the chlorophyll content, photosynthesis, and biomass accumulation of wheat seedlings. Seedling roots became shorter and thicker, and the lateral roots decreased under Cd-stress. The Cd-stress also increased H2O2 and MDA accumulation and the degree of cell membrane lipid peroxidation and affected the activities of antioxidant enzymes such as superoxide dismutase (SOD) and peroxidase (POD). Under Cd stress, exogenous chitosan decreased the Cd content in the aboveground and underground parts of wheat by 13.22 %-21.63 % and 7.92 %-28.32 % and reduced Cd accumulation in the aboveground and underground parts by 5.37 %-6.71 % and 1.91 %-4.09 %, respectively. Whereas exogenous chitosan application significantly reduced the content of H2O2 in roots and aboveground parts of wheat by 38.21 %-47.46 % and 45.81 %-55.73 % and MDA content by 37.65 %-48.12 % and 29.87 %-32.51 %, it increased the activities of SOD and POD in roots by 2.78 %-5.61 % and 13.81 %-18.33 %, respectively. In summary, exogenous chitosan can improve the photosynthetic characteristics and antioxidant enzyme activities of wheat seedlings under Cd stress, reduce the content and accumulation of Cd in the root and aboveground parts of wheat, and alleviate the damage of lipid peroxidation to the cell membrane. All of these results provide the basal data for the application of exogenous chitosan to alleviate Cd toxicity to wheat seedlings.
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Antioxidantes , Cadmio , Quitosano , Plantones , Triticum , Triticum/metabolismo , Triticum/efectos de los fármacos , Triticum/crecimiento & desarrollo , Cadmio/toxicidad , Cadmio/metabolismo , Quitosano/metabolismo , Quitosano/farmacología , Plantones/efectos de los fármacos , Plantones/metabolismo , Antioxidantes/metabolismo , Estrés Fisiológico/efectos de los fármacos , Superóxido Dismutasa/metabolismo , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/metabolismoRESUMEN
The deteriorated plasticity arising from the insoluble precipitates may lead to cracks during the rolling of FeCrAl alloys. The microstructure evolution and hot deformation behavior of an FeCrAl alloy were investigated in the temperature range of 750-1200 °C and strain rate range of 0.01-10 s-1. The flow stress of the FeCrAl alloy decreased with an increasing deformation temperature and decreased strain rate during hot working. The thermal deformation activation energy was determined to be 329.49 kJ/mol based on the compression test. Then, the optimal hot working range was given based on the established hot processing maps. The hot processing map revealed four small instability zones. The optimal working range for the material was identified as follows: at a true strain of 0.69, the deformation temperature should be 1050-1200 °C, and the strain rate should be 0.01-0.4 s-1. The observation of key samples of thermally simulated compression showed that discontinuous dynamic recrystallization started to occur with the temperate above 1000 °C, leading to bended grain boundaries. When the temperature was increased to 1150 °C, the dynamic recrystallization resulted in a microstructure composed of fine and equiaxed grains.
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Background: DHEA is a steroid hormone produced by the gonads, adrenal cortex, brain, and gastrointestinal tract. While the anti-obesity, anti-atherosclerosis, anti-cancer, and memory-enhancing effects of DHEA have been substantiated through cell experiments, animal studies, and human trials, the precise mechanisms underlying these effects remain unclear. Altered mitochondrial dynamics can lead to mitochondrial dysfunction, which is closely related to many human diseases, especially cancer and aging. This study was to investigate whether DHEA inhibits lung adenocarcinoma through the mitochondrial pathway and its molecular mechanism. Methods: Through animal experiments and cell experiments, the effect of DHEA on tumor inhibition was determined. The correlation between FASTKD2 expression and DHEA was analyzed by Western blot, Reverse transcription-quantitative PCR, Immunohistochemistry, and TCGA database. Results: In this study, DHEA supplementation in the diet can inhibit the tumor size of mice, and the effect of adding DHEA one week before the experiment is the best. DHEA limits the glycolysis process by inhibiting G6PDH activity, increases the accumulation of reactive oxygen species, and initiates apoptosis in the mitochondrial pathway of cancer cells. Conclusion: DHEA suppresses mitochondrial fission and promotes mitochondrial fusion by downregulating the expression of FASTKD2, thereby inhibiting tumor growth and prolonging the overall survival of lung adenocarcinoma patients, which also provides a new target for the prevention and treatment of lung adenocarcinoma.
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This research aimed to clarify the mitigative effect of exogenously applied rare earth element cerium ï¼Ceï¼ on the growthï¼ zinc ï¼Znï¼ accumulationï¼ and physiological characteristics of wheat ï¼Triticum aestivum L.ï¼ seedlings under Zn stress. The wheat variety studied was Bainong307 ï¼BN307ï¼ï¼ and Zn stress was achieved by growing seedlings in a hydroponic culture experiment with 500 µmol·L-1 Zn2 + added to the culture solution. It was found that Zn stress at 500 µmol·L-1 significantly inhibited the chlorophyll contentï¼ photosynthesisï¼ and biomass accumulation of wheat seedlings. Seedling roots became shorter and thickerï¼ and the lateral roots decreased under Zn stress. The Zn stress also increased MDA accumulation and the degree of cell membrane lipid peroxidation and reduced soluble protein contents and the activities of antioxidant enzymes such as superoxide dismutase ï¼SODï¼ï¼ catalase ï¼CATï¼ï¼ and ascorbate peroxidase ï¼APXï¼. On the contraryï¼ exogenous Ce decreased the adsorption and transport of Zn by the root system and alleviated the damage of Zn stress to wheat seedlings. Specificallyï¼ the increase in chlorophyll content ï¼chlorophyll aï¼ chlorophyll bï¼ and total chlorophyllï¼ and photosynthetic parametersï¼ the enhancement of antioxidant enzymes activities and soluble protein levelsï¼ and the reduction in MDA content and the damage of lipid peroxidation to the cell membrane were all driven by exogenous Ceï¼ which ultimately led to the increase in dry matter biomass of the root system and shoot. In summaryï¼ these results provide basic data for the application of exogenous Ce to alleviate Zn toxicity to plants.
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Cerio , Zinc , Zinc/metabolismo , Antioxidantes/metabolismo , Plantones , Triticum , Cerio/metabolismo , Cerio/farmacología , Clorofila A , Superóxido Dismutasa/metabolismo , Clorofila , Estrés OxidativoRESUMEN
To explore the effects of different concentrations of zinc ï¼Znï¼ on the growth and root architecture classification of maize seedlings under cadmium ï¼Cdï¼ stressï¼ a hydroponic experiment was conducted to study the effects of different concentrations of Zn ï¼0ï¼ 10ï¼ 25ï¼ 50ï¼ 100ï¼ 200ï¼ and 400 µmol·L-1ï¼ on the growthï¼ root architecture and classification characteristicsï¼ Cd contentï¼ root Cd uptake capacityï¼ and photosynthetic system of maize seedlings under Cd stress ï¼50 µmol·L-1ï¼ by using Zhengdan 958 as the experimental material. Principal component analysis and the membership function method were used for comprehensive evaluation. The results showed that the 50 µmol·L-1 Cd stress had a significant toxic effect on maize seedlingsï¼ which significantly reduced chlorophyll content and photosynthetic parameters. The main root lengthï¼ plant heightï¼ biomassï¼ root forksï¼ and root tipsï¼ including the root length and root surface area of the grade â -â ¢ diameter range and the root volume of the grade â -â ¡ diameter rangeï¼ decreased significantlyï¼ which hindered the normal growth and development of maize seedlings. Compared with that under no Zn applicationï¼ 100 µmol·L-1 and 200 µmol·L-1 Zn application reduced the uptake of Cd by maize seedlingsï¼ significantly reduced the Cd content in shoots and roots and the Cd uptake efficiency. The toxic effect on maize seedlings was alleviatedï¼ and the fresh weightï¼ dry weightï¼ tolerance indexï¼ and root forks of shoots and roots were significantly increased. The photosynthesis of maize seedlings was significantly enhancedï¼ and the photosynthetic rate and the total chlorophyll content was significantly increased. The RLï¼ SAï¼ and RV in the â -â ¡ diameter range reached the maximum at 100 µmol·L-1 Znï¼ and the RLï¼ SAï¼ and RV in the â ¢ diameter range reached the maximum at 200 µmol·L-1 Znï¼ which were significantly higher than those without Zn treatment. The comprehensive evaluation of the growth tolerance of maize seedlings showed that 100 µmol·L-1 and 200 µmol·L-1 Zn had better effects on alleviating Cd toxicity. Comprehensive analysis showed that the application of appropriate concentration of Zn could reduce the Cd content in maize seedlingsï¼ the Cd uptake capacityï¼ and Cd uptake efficiency of rootsï¼ increase the biomass accumulation of maize seedlingsï¼ reduce the effect of Cd toxicity on root architectureï¼ reduce the effect on the light and systemï¼ and improve the tolerance of maize seedlings to Cd.
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Plantones , Contaminantes del Suelo , Zinc , Cadmio , Zea mays , Raíces de Plantas , ClorofilaRESUMEN
The 18O enrichment (Δ18O) of cellulose (Δ18OCel) is recognized as a unique archive of past climate and plant function. However, there is still uncertainty regarding the proportion of oxygen in cellulose (pex) that exchanges post-photosynthetically with medium water of cellulose synthesis. Particularly, recent research with C3 grasses demonstrated that the Δ18O of leaf sucrose (Δ18OSuc, the parent substrate for cellulose synthesis) can be much higher than predicted from daytime Δ18O of leaf water (Δ18OLW), which could alter conclusions on photosynthetic versus post-photosynthetic effects on Δ18OCel via pex. Here, we assessed pex in leaves of perennial ryegrass (Lolium perenne) grown at different atmospheric relative humidity (RH) and CO2 levels, by determinations of Δ18OCel in leaves, Δ18OLGDZW (the Δ18O of water in the leaf growth-and-differentiation zone) and both Δ18OSuc and Δ18OLW (adjusted for εbio, the biosynthetic fractionation between water and carbohydrates) as alternative proxies for the substrate for cellulose synthesis. Δ18OLGDZW was always close to irrigation water, and pex was similar (0.53 ± 0.02 SE) across environments when determinations were based on Δ18OSuc. Conversely, pex was erroneously and variably underestimated (range 0.02-0.44) when based on Δ18OLW. The photosynthetic signal fraction in Δ18OCel is much more constant than hitherto assumed, encouraging leaf physiological reconstructions.
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Dióxido de Carbono , Celulosa , Humedad , Isótopos de Oxígeno , Hojas de la Planta , Sacarosa , Hojas de la Planta/metabolismo , Celulosa/metabolismo , Dióxido de Carbono/metabolismo , Sacarosa/metabolismo , Isótopos de Oxígeno/metabolismo , Lolium/metabolismo , Lolium/crecimiento & desarrollo , Lolium/fisiología , Atmósfera , Fotosíntesis , Agua/metabolismoRESUMEN
Guaico Culex virus (GCXV) is a newly identified segmented Jingmenvirus from Culex spp. mosquitoes in Central and South America. The genome of GCXV is composed of four or five single-stranded positive RNA segments. However, the infection kinetics and transmission capability of GCXV in mosquitoes remain unknown. In this study, we used reverse genetics to rescue two GCXVs (4S and 5S) that contained four and five RNA segments, respectively, in C6/36 âcells. Further in vitro characterization revealed that the two GCXVs exhibited comparable replication kinetics, protein expression and viral titers. Importantly, GCXV RNAs were detected in the bodies, salivary glands, midguts and ovaries of Culex quinquefasciatus at 4-10 days after oral infection. In addition, two GCXVs can colonize Cx. quinquefasciatus eggs, resulting in positive rates of 15%-35% for the second gonotrophic cycle. In conclusion, our results demonstrated that GCXVs with four or five RNA segments can be detected in Cx. quinquefasciatus eggs during the first and second gonotrophic cycles after oral infection.
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Culex , Mosquitos Vectores , ARN Viral , Replicación Viral , Animales , Culex/virología , Mosquitos Vectores/virología , ARN Viral/genética , Femenino , Línea Celular , Flavivirus/genética , Flavivirus/fisiología , Flavivirus/aislamiento & purificación , Cinética , Carga Viral , Genoma Viral , Glándulas Salivales/virologíaRESUMEN
Global-minimum optimizations combined with relativistic quantum chemistry calculations have been performed to characterize the ground-state stable structures of four titled compounds and to analyze the bonding properties. Th2C8 was identified as being a ThC4-Th(C2)2 structure, U2C8 has been found to favor the U-U(C8) structure, and both Th3C8 and U3C8 adopt the (AnC3)2-(AnC2) structure. Then, the wave function analyses reveal that the interactions between the Th 7s-based orbital and the σg molecular orbital of the C2 unit compensate for the excitation energy of 7s16d1 â 6d2 and lead to the stabilization of two Th(IV)s in the ThC4-Th(C2)2 structure. It also reveals that the U species exhibit magnetic exchange coupling behavior in UxC8, for instance, as seen in the direct interaction of U2C8 and the superexchange pathway of U3C8, which effectively stabilizes their low-spin states. This interpretation indicates that the geometric and electronic structures of AnxC8 species are largely influenced by the local magnetic moment and spin correlation.
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The 13C isotope composition (δ13C) of leaf dry matter is a useful tool for physiological and ecological studies. However, how post-photosynthetic fractionation associated with respiration and carbon export influences δ13C remains uncertain. We investigated the effects of post-photosynthetic fractionation on δ13C of mature leaves of Cleistogenes squarrosa, a perennial C4 grass, in controlled experiments with different levels of vapour pressure deficit and nitrogen supply. With increasing leaf age class, the 12C/13C fractionation of leaf organic matter relative to the δ13C of atmosphere CO2 (ΔDM) increased while that of cellulose (Δcel) was almost constant. The divergence between ΔDM and Δcel increased with leaf age class, with a maximum value of 1.6, indicating the accumulation of post-photosynthetic fractionation. Applying a new mass balance model that accounts for respiration and export of photosynthates, we found an apparent 12C/13C fractionation associated with carbon export of -0.5 to -1.0. Different ΔDM among leaves, pseudostems, daughter tillers, and roots indicate that post-photosynthetic fractionation happens at the whole-plant level. Compared with ΔDM of old leaves, ΔDM of young leaves and Δcel are more reliable proxies for predicting physiological parameters due to the lower sensitivity to post-photosynthetic fractionation and the similar sensitivity in responses to environmental changes.
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Celulosa , Poaceae , Poaceae/metabolismo , Celulosa/metabolismo , Isótopos de Carbono , Fotosíntesis/fisiología , Carbono , Hojas de la Planta/metabolismo , Dióxido de CarbonoRESUMEN
A pair of new chromone derivative enantiomers, (+)-xylarichromone A (1a) and (-)-xylarichromone A (1b), were isolated from the solid fermentation of Xylaria nigripes. The planar structure of 1 was determined by extensive NMR spectroscopic data, and its absolute configuration was assigned by comparison the ECD spectra with the known chromone derivatives. Compound 1 was the first chromone derivative reported from this medicinal fungus. The neuroprotective effects of 1 against oxygen and glucose deprivation (OGD) induced pheochromocytoma-12 cells (PC12) injury was investigated.
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Ascomicetos , Cromonas , Cromonas/farmacología , Cromonas/química , Estructura Molecular , Espectroscopía de Resonancia MagnéticaRESUMEN
OBJECTIVE: To quantify the results of superficial parotidectomy (SP) and partial SP (PSP) for benign parotid tumours using a systematic evaluation method. METHODS: A systematic search of English and Chinese databases (PubMed, Web of Science, Cochrane Library, China Knowledge Network, Wanfang and Vipshop) was conducted to include studies comparing the treatment outcomes of SP with PSP. RESULTS: Twenty-three qualified, high-quality studies involving 2844 patients were included in this study. The results of this study showed that compared to the SP surgical approach, the PSP surgical approach reduced the occurrence of temporary facial palsy (OR = 0.33; 95% confidence interval [CI] 0.26-0.41), permanent facial palsy (OR = 0.28; 95% CI 0.16-0.52) and Frey syndrome (OR = 0.36; 95% CI 0.23-0.56) in patients after surgery, and the surgery operative time was reduced by approximately 27.35 min (95% CI - 39.66, - 15.04). However, the effects of PSP versus SP on salivary fistula (OR = 0.70; 95% CI 0.40-1.24), sialocele (OR = 1.48; 95% CI 0.78-2.83), haematoma (OR = 0.34; 95% CI 0.11-1.01) and tumour recurrence rate (OR = 1.41; 95% CI 0.48-4.20) were not statistically significant. CONCLUSION: Compared with SP, PSP has a lower postoperative complication rate and significantly shorter operative time, suggesting that it could be used as an alternative to SP in the treatment of benign parotid tumours with the right indications.
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Parálisis Facial , Neoplasias de la Parótida , Humanos , Parálisis Facial/etiología , Parálisis Facial/prevención & control , Glándula Parótida/cirugía , Neoplasias de la Parótida/cirugía , Neoplasias de la Parótida/patología , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/patología , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Schisandra chinensis is a monoecious plant with unisex flowers. The fruit of S. chinensis is of high medical with economic value. The yield of S. chinensis fruit is related to the ratio of its female and male flowers. However, there is little research on its floral development and sex differentiation. To elucidate the possible mechanism for the sex differentiation of S. chinensis, we collected 18 samples of female and male flowers from three developmental stages and performed a comparative RNA-seq analysis aimed at identifying differentially expressed genes (DEGs) that may be related to sex differentiation. The results showed 936, 7179, and 6890 differentially expressed genes between female and male flowers at three developmental stages, respectively, and 466 candidate genes may play roles in sex differentiation. KEGG analysis showed genes involved in the flavonoid biosynthesis pathway and DNA replication pathway were essential for the development of female flowers. 51 MADS-box genes and 10 YABBY genes were identified in S. chinensis. The DEGs analysis indicated that MADS-box and YABBY genes were strongly related to the sex determination of S. chinensis. RT-qPCR confirmed the RNA-seq results of 20 differentially expressed genes, including three male-biased genes and 17 female-biased genes. A possible regulatory model of sex differentiation in S. chinensis was proposed according to our results. This study helps reveal the sex-differentiation mechanism of S. chinensis and lays the foundation for regulating the male-female ratio of S. chinensis in the future.
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Schisandra , Schisandra/genética , Diferenciación Sexual , Perfilación de la Expresión Génica , Transcriptoma , Flores , Regulación de la Expresión Génica de las PlantasRESUMEN
Objective: To investigate the effect of different bladder filling states on positioning errors in radiotherapy for cervical cancer and obtain the reference range of bladder filling consistency during radiotherapy.Methods: Patients who underwent postoperative radiotherapy for cervical cancer in Nantong Tumor Hospital from October 2018 to December 2019 were selected. According to the bladder filling deviation, they were divided into group A1 (deviation < 20%) and group B1 (deviation ≥ 20%). The bladder filling variations of the two groups were compared with different positioning errors. Group A2 has a positioning error of <0.4 cm, and group B2 has a positioning error of ≥0.4 cm. The reference range of bladder filling consistency during radiotherapy is obtained by analyzing the composition ratio of different positioning errors of bladder filling deviation.Results: This study included 195 patients with cervical cancer. The error of longitudinal and vertical position in group B1 was significantly higher than that in group A1 (0.50 ± 0.34 vs. 0.26 ± 0.22 cm, p < 0.001, and 0.22 ± 0.17 vs. 0.16 ± 0.12 cm, p < 0.001). Compared with group B2, the absolute deviation of bladder filling in group A2 (54.1% ± 54.4% vs. 25.6% ± 22.7%, p < 0.001) was slight. The chi-square test showed significant differences in the proportion of the positioning state of different bladder filling forms (χ2 = 31.006, p < 0.001). In addition, there was a significant difference in the proportion of stability errors in patients with poor stability in different directions (χ2 = 118.551, p < 0.001).Conclusion: In patients with cervical cancer fixed in the supine position, a bladder capacity deviation <20% is easier to achieve excellent positioning with, and it can better control the positioning error of radiotherapy and ensure the positioning accuracy of dose distribution to the target area. It can also achieve good tumor treatment effects. This range can be used as a reference for bladder filling consistency in patients with cervical cancer undergoing radiotherapy.
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Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/radioterapia , Neoplasias del Cuello Uterino/cirugía , Vejiga Urinaria/cirugía , Histerectomía , Valores de ReferenciaRESUMEN
Hydrogel microfibers, which are characterized by flexible mechanical properties, a uniform spatial distribution, large surface areas, and excellent biocompatibility, hold great potential for various biomedical applications. However, the fabrication of heterogeneous hydrogel microfibers with high cell-loading capacity and the ability to carry multiple components via an environmentally friendly method remains challenging. In this study, we developed a novel pneumatic pump-assisted all-aqueous microfluidic system that enables the one-step fabrication of all-aqueous droplet-filled hydrogel microfibers with unique morphologies and adjustable configurations. By designing a pump-valve cycling system and selecting two immiscible fluids with stable water interfaces (dextran and polyethylene glycol), we successfully fabricated alginate microfibers with equidistantly arranged droplets through the ionotropic gelation reaction between sodium alginate and calcium chloride. The droplet size, interdroplet spacing, and microfiber dimensions could be flexibly controlled by adjusting the flow rates of the inner-phase, middle-phase, and outer-phase inlets. The results showed that the system enabled the high-throughput in situ formation of functional three-dimensional cell spheroids. The generated cell spheroids exhibited excellent cell viability and drug-testing functionality, indicating their potential applications in cell cultures. The developed technique offers strong support for future biomedical research and applications, and provides a new approach for the preparation of multifunctional hydrogel microfibers for materials science, tissue engineering, and drug testing.
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Hidrogeles , Microfluídica , Técnicas de Cultivo Tridimensional de Células , Polietilenglicoles , Detección de Abuso de SustanciasRESUMEN
INTRODUCTION: Quitting smoking, the critical path to reach the global targets of reducing tobacco use, can bring major and immediate health benefits to smokers. Exploring factors that help individuals to quit smoking is of great importance. The present study explored influencing factors on smoking cessation, in order to provide comprehensive reference for tobacco control policies. METHODS: Ex-smokers and current smokers were recruited online in this cross-sectional survey, from 1 October to 31 November 2022, in China. The observational data were collected using a questionnaire to collect information with respect to sociodemographic characteristics of smokers, attitudes towards smoking cessation, details of smoking cessation, and different potential factors related to smoking cessation through open-ended questions. RESULTS: A total of 638 smokers from 30 provinces were recruited as eligible respondents, with a mean age of 37.3 ± 11.7 years and a mean smoking history of 15.9 ± 13.7 years. The percentage of males was 92.3%. Of the 638 respondents, only 3.9% had no intention to stop smoking. Among 155 subjects who had quitted smoking successfully, willpower (55.5%) was considered as the most important contributing factor. Among 365 subjects who tried to quit but failed, lack of willpower (28.2%), tobacco dependence (16.2%), influence of surrounding smokers or smoking environments (15.9%), bad moods (9.9%), stress from work or life (7.9%), habits (7.1%), socialization (4.1%), and easy availability of tobacco (2.7%) were considered as the adverse factors leading to failure in quitting smoking. CONCLUSIONS: Willpower and support from family members were the vital factors that lead to successful smoking cessation. Future tobacco control policies should also focus on addressing withdrawal symptoms and creating smoke-free environments as well as other factors.
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Background: Structural autografts harvested from the iliac bone have been used in atlantoaxial fusion; they have been the gold standard for years. However, emerging occipital bone grafts have the advantage of avoiding donor-site morbidity and complications. Thus, we compared the clinical outcomes of structural autografts from the occipital bone or iliac crest and discussed the clinical significance of occipital bone grafts in pediatric patients. Methods: Pediatric patients who underwent posterior fusion using occipital bone grafts (OBG) or iliac bone grafts (IBG) between 2017 and 2021 were included in this study. Data on clinical outcomes, including operation time, estimated blood loss, length of hospitalization, complications, fusion rate, and fusion time, were collected and analyzed. Additionally, 300 pediatric patients who underwent cranial computed tomography scans were included in the bone thickness evaluation procedure. The central and edge thicknesses of the harvested areas were recorded and analyzed. Results: Thirty-nine patients were included in this study. There were no significant differences in patient characteristics between the OBG and IBG groups. Patients in both groups achieved a 100% fusion rate; however, the fusion time in the OBG group was significantly longer than that in the IBG group. Estimated blood loss, operation time, and length of hospitalization were significantly lower in the OBG group than those in the IBG group. The surgery-related complication rate was lower, but not significantly, in the OBG group than that in the IBG group. For occipital bone thickness evaluation, a significant difference in the central part of the harvesting area was found between the young and old groups, with no significant sex differences. Conclusion: The use of OBG for atlantoaxial fusion is acceptable for pediatric patients with atlantoaxial dislocation, avoiding donor-site morbidity and complications.
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OBJECTIVE: To investigate the efficacy and safety of posterior atlantoaxial fusion (AAF) with C1-2 pedicle screw fixation for atlantoaxial dislocation (AAD) in pediatric patients with mucopolysaccharidosis IVA (MPS IVA). METHODS: This study included 21 pediatric patients with MPS IVA who underwent posterior AAF with C1-2 pedicle screw fixation. Anatomical parameters of the C1 and C2 pedicle were measured on preoperative computed tomography (CT). The American Spinal Injury Association (ASIA) scale was used to evaluate the neurological status. The fusion and accuracy of pedicle screw was assessed on postoperative CT. Demographic, radiation dose, bone density, surgical, and clinical data were recorded. RESULTS: Patients reviewed included 21 patients younger than 16 years with an average age of 7.4 ± 4.2 years and an average of 20.9 ± 7.7 months follow-up. Fixation of 83 C1 and C2 pedicle screws was performed successfully and 96.3% of them were identified as being safe. One patient developed postoperative transient disturbance of consciousness and one developed fetal airway obstruction and died about 1 month after the surgery. Out of the remaining20 patients, fusion was achieved, symptoms were improved, and no other serious surgical complications were observed at the latest follow-up. CONCLUSIONS: Posterior AAF with C1-2 pedicle screw fixation is effective and safe for AAD in pediatric patients with MPS IVA. However, the procedure is technically demanding and should be performed by experienced surgeons with strict multidisciplinary consultations.
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Articulación Atlantoaxoidea , Luxaciones Articulares , Inestabilidad de la Articulación , Mucopolisacaridosis , Mucopolisacaridosis IV , Traumatismos del Cuello , Tornillos Pediculares , Fusión Vertebral , Traumatismos Vertebrales , Espondiloartropatías , Humanos , Niño , Preescolar , Mucopolisacaridosis IV/cirugía , Fusión Vertebral/métodos , Luxaciones Articulares/diagnóstico por imagen , Luxaciones Articulares/cirugía , Articulación Atlantoaxoidea/diagnóstico por imagen , Articulación Atlantoaxoidea/cirugía , Inestabilidad de la Articulación/cirugía , Vértebras Cervicales/cirugíaRESUMEN
Schisandra chinensis, a traditional Chinese medicinal herb, is rich in chemical constituents, including lignans, triterpenes, polysaccharides, and volatile oils. Clinically, it is commonly used to treat cardiovascular, cerebrovascular, liver, gastrointestinal, and respiratory diseases. Modern pharmacological studies have shown that S. chinensis extract and monomers have multiple pharmacological activities in lowering liver fat, alleviating insulin resistance, and resisting oxidative stress, and have good application prospects in alleviating nonalcoholic fatty liver disease(NAFLD). Therefore, this study reviewed the research progress on chemical constituents of S. chinensis and its effect on NAFLD in recent years to provide references for the research on S. chinensis in the treatment of NAFLD.
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Resistencia a la Insulina , Lignanos , Enfermedad del Hígado Graso no Alcohólico , SchisandraRESUMEN
In this paper, we have explored the relativistic density functional theory study on a series of deprotonated porphyrinoid (Ln) complexes of uranyl to investigate the geometrical structures and chemical bonding. The ligands bound with uranyl in the 1:1 complexes [UO2(Ln)]x (n = 4, 5, 6; x = 0, -1, -2), showing more thermodynamic stability for "in-cavity" structures of L5 and L6 than that of the "side-on" structure of L4 and an increase in stability with the increase of negative charges, L2- < L3- < L4-. Among the six ligands, the cyclo[6]pyrrole presents the best selectivity toward uranyl. Based on chemical bonding analyses, the U-NL bond in the in-cavity complexes adopts a typical dative NL â U bond with mainly ionic bonding and significant covalency, which comes from the significant orbital interaction of U 5fÏ6dδ7s hybrid AOs and NL 2p-based MOs. This work provides a systematic understanding of the coordination chemistry in uranyl pyrrole-containing macrocycle complexes and the nature of chemical bonding in such systems, which may provide inspirations for the future design of synthetic targets that could be relevant to actinide separations or in the remediation of spent nuclear fuel.