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The management of anesthesia in elderly patients undergoing surgery presents unique challenges, particularly in mitigating stress responses and ensuring stability. Etomidate may alleviate adrenocortical and immune stress. This study aims to investigate the anesthetic effects of combined spinal-epidural anesthesia (CSEA) supplemented with etomidate during anorectal surgery in elderly patients. The medical records of 49 cases treated with CSEA and etomidate (ETO group) and 48 cases treated with CSEA alone (control group) were reviewed and analyzed. All patients received ropivacaine hydrochloride for anesthesia, with the ETO group additionally receiving an infusion of etomidate for sedation. Parameters such as arterial blood gas, visual analog scale (VAS), Ramsay sedation scale (RSS), serum cortisol and norepinephrine levels, pro-inflammatory cytokines, and lymphocyte ratios were assessed at different time points. Compared to the control group, the ETO group showed increased mean arterial pressure, decreased heart rate, and elevated arterial SpO2 30 minutes after anesthesia. The ETO group also had higher RSS scores, lower VAS scores, and reduced serum cortisol and norepinephrine levels. Additionally, decreased levels of pro-inflammatory cytokines, such as interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-8, were observed, along with an increase in the regulatory cytokine IL-10. An increased proportion of CD4+ T cells and a higher CD4/CD8 ratio were also noted. This study demonstrates the benefits of using etomidate to mitigate adrenocortical and immune stress in elderly patients undergoing anorectal surgery.
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BACKGROUND: The use of ionic liquids (ILs) to fractionate lignocelluloses for various bio-based chemicals productions is in the ascendant. On this basis, the protic ILs consisting of triethylammonium hydrogen sulfate ([TEA][HSO4]) possessed great promise due to the low price, low pollution, and high efficiency. In this study, the microwave-assistant [TEA][HSO4] fractionation process was established for corn stover fractionation, so as to facilitate the monomeric sugars production and supported the downstream acetone-butanol-ethanol (ABE) fermentation. RESULTS: The assistance of microwave irradiation could obviously shorten the fractionation period of corn stover. Under the optimized condition (190 W for 3 min), high xylan removal (93.17 ± 0.63%) and delignification rate (72.90 ± 0.81%) were realized. The mechanisms for the promotion effect of the microwave to the protic ILs fractionation process were ascribed to the synergistic effect of the IL and microwaves to the depolymerization of lignocellulose through the ionic conduction, which can be clarified by the characterization of the pulps and the isolated lignin specimens. Downstream valorization of the fractionated pulps into ABE productions was also investigated. The [TEA][HSO4] free corn stover hydrolysate was capable of producing 12.58 g L-1 of ABE from overall 38.20 g L-1 of monomeric sugars without detoxification and additional nutrients supplementation. CONCLUSIONS: The assistance of microwave irradiation could significantly promote the corn stover fractionation by [TEA][HSO4]. Mass balance indicated that 8.1 g of ABE and 16.61 g of technical lignin can be generated from 100 g of raw corn stover based on the novel fractionation strategy.
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Deep eutectic solvents (DESs) offer a potential opportunity in biomass utilization industries. This work emphasized the impact of hydrogen bond donors (HBD) and acceptors (HBA) on deconstruction and valorization of rice straw. Acidity, alkyl chain length, hydrogen bonding ability and functional groups of HBD and HBA appeared to be important factors affecting the fractionated pulps and lignins, which further influenced ethanol fermentation. Among the candidate DESs, lactic acid/guanidine hydrochloride (LGH) was proved to be the most suitable one due to the excellent delignification and xylan removal. For the downstream fermentation process, 0.47 g g-1 of bioethanol with 0.55 g/L h-1 of productivity can be obtained from the LGH pulp's hydrolysate. Mass balance showed 302.8 g bioethanol and 119.0 g technical lignin can be co-generated from 1 kg dried rice straw. This "green" valorization strategy offers a promising scheme in biorefinery of lignocelluloses.
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Lignina , Oryza , Lignina/química , Solventes Eutéticos Profundos , Solventes/química , Biomassa , HidróliseRESUMO
The aim of this research was to explore the therapeutic capabilities of extracellular vesicles (EVs) derived from human umbilical cord mesenchymal stem cells (hUC-MSCs) that had been subjected to heat shock pretreatment, in treating psychiatric disorders induced by sleep deprivation in mice. The EVs were isolated and characterized, while western blotting was utilized to assess the expression of exosomal markers and heat shock protein 70 (HSP70). To evaluate the impact of EV treatment on anxiety-like behavior and cognitive impairment in sleep-deprived (SD) mice, the open field test, plus maze test, and Y-maze task were conducted. Heat shock pretreatment significantly increased the expression of HSP70 in EVs. Administration of EVs from heat shock-pretreated hUC-MSCs improved anxiety-like behavior and cognitive function in SD mice. Furthermore, EV treatment promoted synaptic protein expression, HSP70 expression and inhibited neuroinflammation in the hippocampus of SD mice. Western blotting analysis also revealed that EV treatment reduced the levels of TLR4 and p65 in the hippocampus. EVs from heat shock-pretreated hUC-MSCs have therapeutic potential for sleep deprivation-induced psychiatric disorders by regulating neuroinflammation and synaptic function in mice.
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Cis, cis-muconic acid (MA) is widely used as a key starting material in the synthesis of diverse polymers. The growing demand in these industries has led to an increased need for MA. Here, we constructed recombinant Corynebacterium glutamicum by systems metabolic engineering, which exhibit high efficiency in the production of MA. Firstly, the three major degradation pathways were disrupted in the MA production process. Subsequently, metabolic optimization strategies were predicted by computational design and the shikimate pathway was reconstructed, significantly enhancing its metabolic flux. Finally, through optimization and integration of key genes involved in MA production, the recombinant strain produced 88.2 g/L of MA with the yield of 0.30 mol/mol glucose in the 5 L bioreactor. This titer represents the highest reported titer achieved using glucose as the carbon source in current studies, and the yield is the highest reported for MA production from glucose in Corynebacterium glutamicum. Furthermore, to enable the utilization of more cost-effective glucose derived from corn straw hydrolysate, we subjected the strain to adaptive laboratory evolution in corn straw hydrolysate. Ultimately, we successfully achieved MA production in a high solid loading of corn straw hydrolysate (with the glucose concentration of 83.56 g/L), resulting in a titer of 19.9 g/L for MA, which is 4.1 times higher than that of the original strain. Additionally, the glucose yield was improved to 0.33 mol/mol. These provide possibilities for a greener and more sustainable production of MA.
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Corynebacterium glutamicum , Ácido Sórbico/análogos & derivados , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Reatores Biológicos/microbiologia , Glucose/genética , Glucose/metabolismo , Ácido Sórbico/metabolismo , Engenharia Metabólica/métodos , FermentaçãoRESUMO
BACKGROUND: The effective valorization of lignin and carbohydrates in lignocellulose matrix under the concept of biorefinery is a primary strategy to produce sustainable chemicals and fuels. Based on the reductive catalytic fractionation (RCF), lignin in lignocelluloses can be depolymerized into viscous oils, while the highly delignified pulps with high polysaccharides retention can be transformed into various chemicals. RESULTS: A biorefinery paradigm for sequentially valorization of the main components in poplar sawdust was constructed. In this process, the well-defined low-molecular-weight phenols and bioethanol were co-generated by tandem chemo-catalysis in the RCF stage and bio-catalysis in fermentation stage. In the RCF stage, hydrogen transfer reactions were conducted in one-pot process using Raney Ni as catalyst, while the isopropanol (2-PrOH) in the initial liquor was served as a hydrogen donor and the solvent for lignin dissolution. Results indicated the proportion of the 2-PrOH in the initial liquor of RCF influenced the chemical constitution and yield of the lignin oil, which also affected the characteristics of the pulps and the following bioethanol production. A 67.48 ± 0.44% delignification with 20.65 ± 0.31% of monolignols yield were realized when the 2-PrOH:H2O ratio in initial liquor was 7:3 (6.67 wt% of the catalyst loading, 200 °C for 3 h). The RCF pulp had higher carbohydrates retention (57.96 ± 2.78 wt%), which was converted to 21.61 ± 0.62 g/L of bioethanol with a yield of 0.429 ± 0.010 g/g in fermentation using an engineered S. cerevisiae strain. Based on the mass balance analysis, 104.4 g of ethanol and 206.5 g of lignin oil can be produced from 1000 g of the raw poplar sawdust. CONCLUSIONS: The main chemical components in poplar sawdust can be effectively transformed into lignin oil and bioethanol. The attractive results from the biorefinery process exhibit great promise for the production of valuable biofuels and chemicals from abundant lignocellulosic materials.
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In this study, a surfactant-assisted diluted ethylenediamine (EDA) fractionation process was investigated for co-generation of technical lignin and biobutanol from corn stover. The results showed that the addition of PEG 8000 significantly enhanced cellulose recovery (88.9 %) and lignin removal (68.9 %) in the solid fraction. Moreover, the pulp achieved 86.5 % glucose yield and 82.6 % xylose yield in enzymatic hydrolysis. Structural characterization confirmed that the fractionation process promoted the preservation of active ß-O-4 bonds (35.8/100R) in isolated lignin and functionalized the lignin through structural modification using EDA and surfactant grafting. The enzymatic hydrolysate of the pulps yielded a sugar solution for acetone-butanol-ethanol (ABE) fermentation, resulting in an ABE concentration of 15.4 g/L and an overall yield of 137.2 g/Kg of dried corn stalk. Thus, the surfactant-assisted diluted EDA fractionation has the potential to enhance the overall economic feasibility of second-generation biofuels production within the framework of biorefinery.
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Lignina , Zea mays , Lignina/química , Zea mays/metabolismo , Tensoativos , Celulose/metabolismo , Butanóis/química , 1-Butanol , Etilenodiaminas , Hidrólise , FermentaçãoRESUMO
BACKGROUND: Many neurobehavioral processes, including psychomotor, cognitive, and affection are negatively impacted by sleep deprivation (SD), which may be harmful to a person's physical and mental health. Heat shock proteins (Hsps) have been demonstrated to play a protective role in a number of neurodegenerative diseases and are essential for maintaining intracellular protein homeostasis, but their roles in SD remain elusive. METHODS: A mouse SD model was constructed using a modified multi-platform water environment method. The cognitive function was tested by novel object recognition test and Y-maze test, and anxiety-like behaviors were assessed by open field test (OFT). Protein expression was determined by Western blotting assay and ELISA assay. RESULTS: We found that SD could profoundly enhance anxiety levels and impair cognitive function in mice. SD also reduced the expression levels of p-cAMP-response element binding protein (CREB) and brain-derived neurotrophic factor (BDNF) and increased microglial activation and neuroinflammatory response in the hippocampus of mice. The intranasal injection of human recombinant Hsp70 protein could alleviate SD-induced anxiety and cognitive impairment, as well as restore pCREB and BDNF levels and reduce microglia-induced neuroinflammation in the hippocampus of SD mice. CONCLUSIONS: Hsp70 treatment might serve as a potential treatment for mitigating SD-related unfavorable symptoms.
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Disfunção Cognitiva , Privação do Sono , Camundongos , Humanos , Animais , Privação do Sono/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Cognição , Hipocampo/metabolismo , Ansiedade/tratamento farmacológicoRESUMO
Palmitoleic acid (POA) has been widely applied to nutrition and pharmaceutical industry. However, high cost of scale-up fermentation restricts the extensive application of POA. Hence, we investigated the availability of corn stover hydrolysate (CSH) as carbon source in POA production by engineered S. cerevisiae. Although the yeast growth was inhibited to some extent by CSH, the POA production with CSH was slightly higher than that with pure glucose. The C/N ratio of 120 and addition of 1 g/L lysine raised the POA titer up to 2.19 g/L and 2.05 g/L, respectively. Two-stage cultivation could increase the POA titer by upregulating the gene expression of key enzymes in fatty acid synthesis pathway. A high POA content of 57.5% (v/v) and a highest POA titer of 6.56 g/L were achieved under the optimized conditions. These findings provide a feasible approach for sustainable production of POA or its derivatives from CSH.
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Saccharomyces cerevisiae , Zea mays , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Zea mays/metabolismo , Fermentação , Ácidos Graxos Monoinsaturados/metabolismoRESUMO
Shape-stable phase change materials (ss-PCMs) are extensively applied in renewable energy storage. The core for realizing high latent heat and good thermal stability of ss-PCMs is the designation of suitable supporting skeletons that can effectively preserve the PCMs from leaking out. In this study, ss-PCMs impregnated by D-mannitol were prepared using a waste yeast-derived carbon (YC) as the support material. YC possesses a large surface area (669.90 m2/g), which can provide sufficient phase transition space and nucleation sites for D-mannitol. The results indicated that a reduced supercooling of 44.76 °C for YC/D-mannitol ss-PCMs can be realized. The ss-PCMs also exhibited good cycling stability, with latent heat loss rates of 4.00% and 2.15% after 200 thermal cycles. We further demonstrate that YC provides restricted space for mannitol to inhibit the supercooling mechanism. The YC/D-mannitol ss-PCMs exhibited great promise for solar heat storage and industrial waste heat recovery in the medium temperature domain.
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Increased absorption of visible light, low electron-hole recombination, and fast electron transfer are the major objectives for highly effective photocatalysts in biocatalytic artificial photosynthetic systems. In this study, a polydopamine (PDA) layer containing electron mediator, [M], and NAD+ cofactor was assembled on the outer surface of ZnIn2 S4 nanoflower, and the as-prepared nanoparticle, ZnIn2 S4 /PDA@poly/[M]/NAD+ , was used for photoenzymatic methanol production from CO2 . Because of effective capturing of visible light, reduced distance of electron transfer, and elimination of electron-holes recombination, a high NADH regeneration of 80.7±1.43 % could be obtained using the novel ZnIn2 S4 /PDA@poly/[M]/NAD+ . In the artificial photosynthesis system, a maximum methanol production of 116.7±11.8 µm was obtained. The enzymes and nanoparticles in the hybrid bio-photocatalysis system could be easily recovered using the ultrafiltration membrane at the bottom of the photoreactor. This is due to the successful immobilization of the small blocks including the electron mediator and cofactor on the surface of the photocatalyst. The ZnIn2 S4 /PDA@poly/[M]/NAD+ photocatalyst exhibited good stability and recyclability for methanol production. The novel concept presented in this study shows great promise for other sustainable chemical productions through artificial photoenzymatic catalysis.
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Dióxido de Carbono , Metanol , Elétrons , NAD/metabolismo , FotossínteseRESUMO
This study aimed to investigate the differential effects of remifentanil and sufentanil anesthesia on post-operative pain and recovery of cognitive functions following surgical resection of human colon cancer orthotopically transplanted in rats. Human colon cancer cells HT-29 were used to establish a rat model of orthotopically transplanted colon cancer on to the cecal wall of rats. The transplanted tumors were then surgically removed after 5 weeks, using different doses of remifentanil and sufentanil anesthesia. At 24 h after the surgery, von Frey test, hot plate test and voluntary wheel running test were used to evaluated post-operative pain in the rats. Morris water maze test and fear conditioning test were employed to assess cognitive functions. Serum and colon tissues of the rats were also subjected to ELISA to measure levels of stress response factors, while colon tissues were analyzed by RT-PCR and Western blot to measure expression of inflammation response factors and NF-κB pathway-related factors. Sufentanil showed better effect in reducing post-operative pain, while remifentanil showed better recovery of cognitive functions after surgery. In addition, remifentanil resulted in less stress and inflammation response, caused milder activation of NF-κB pathway-related factors after surgery. Remifentanil and sufentanil exhibited differential effects on post-operative pain and recovery of cognitive function. Specifically, remifentanil caused lower stress and inflammation response, associated with dampened activation of the NF-κB pathway. Our results could provide theoretical basis for adopting appropriate analgesic strategy and agents according to the characteristics of individual patients.
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Anestesia , Neoplasias do Colo , Analgésicos Opioides/uso terapêutico , Animais , Cognição , Humanos , Inflamação , Atividade Motora , NF-kappa B , Dor Pós-Operatória/tratamento farmacológico , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Ratos , Remifentanil , Sufentanil/uso terapêuticoRESUMO
The facile fabrication of low-cost photocatalysts with enhanced activity and high atomic utilization is becoming increasingly necessary for solar energy usage and/or conversion. In this work, a series of mesoporous carbon nitride nanosheets with an enlarged specific surface area was synthesized via an inorganic acid-assisted exfoliation method without any soft or hard templates. An ultralow loading of downsized noble metal Pt was anchored on these porous nanosheets, exhibiting enhanced photocatalytic activity. The formation of mesoporous nanosheets in carbon nitride was expected to boost the mass transfer and shorten the charge carrier transfer route during the photocatalytic reaction. The characterization of samples revealed that the enhanced conductivity and photocurrent of the carbon nitride nanosheets also contributed to the enhanced H2 evolution activity. The maximum H2 production rates of 172.92 µmol h-1 and 321 µmol h-1 were achieved over the nanosheets derived from melamine and urea under visible light irradiation, which are 10.92- and 2.22-fold that of the corresponding bulk carbon nitride, respectively. This exfoliation method was demonstrated to be an efficient and universal method for the preparation of carbon nitride nanosheets with a mesoporous structure and high atom utilization of the co-catalyst for H2 evolution from water.
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BACKGROUND: This study aimed to investigate the effect of preoperative ultrasound-guided stellate ganglion block (SGB) on the perioperative stress responses and gastrointestinal functions of patients undergoing laparoscopic colorectal cancer surgery. METHODS: A total of 60 colorectal cancer patients were enrolled in study and were randomized to be treated with or without SGB therapy. In the SGB group, patients were injected with 7â¯mL 0.5% ropivacaine in stellate ganglion under ultrasound guidance before anesthesia. Mean artery pressure (MAP), heart rate (HR), recovery of bowel sound and first exhaust, as well as levels of motilin, gastrin, norepinephrine, cortisol, interleukin-6 (IL-6) and C-reactive protein (CRP) were recorded at various time points. RESULTS: 26 patients in the SGB group and 27 patients in the control group were analyzed. No significant differences in MAP or HR were observed between the two groups before, during and after the surgery. SGB promoted recovery of gastrointestinal functions, as evidenced by earlier recovery of bowel sound and first exhaust, as well as increased motilin and gastrin levels. SGB also attenuated stress responses, as shown in reduced norepinephrine, cortisol, IL-6 and CRP levels. CONCLUSIONS: SGB promotes the recovery of gastrointestinal functions and reduces stress responses of colorectal patients undergoing laparoscopic colorectal cancer surgery.
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Bloqueio Nervoso Autônomo/métodos , Neoplasias Colorretais/cirurgia , Idoso , Anestésicos Locais/administração & dosagem , Feminino , Humanos , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Ropivacaina/administração & dosagem , Método Simples-Cego , Gânglio Estrelado , Estresse Fisiológico , Ultrassonografia de IntervençãoRESUMO
Filtration via a porous medium is a ubiquitous process where high-fidelity physical models are needed. The classical cell model oversimplifies the filtration medium and results in biased and inaccurate predictions of the filter performance. This paper presents the discrete framework of a polydisperse cell model that can incorporate any measured pore size distribution. A new equation connecting the polydisperse cell efficiencies and the medium efficiency is derived from first principles. For ceramic filters, the discrete model demonstrates a generic prediction capability of the filtration efficiency with a root-mean-squared difference of 5.4%, while the counterpart of the classical cell model is 26.4%. In addition, the discrete model eliminates the biased predictions of the classical cell model on sub-100 nm particles.
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Filtração , Modelos Teóricos , Tamanho da Partícula , PorosidadeRESUMO
The nanocomposite preparation procedure plays an important role in achieving a well-established heterostructured junction, and hence, an optimized photocatalytic activity. In this study, a series of g-C3N4/ZnO nanocomposites were prepared through two distinct procedures of a low-cost, environmentally-friendly, in-situ fabrication process, with urea and zinc acetate being the only precursor materials. The physicochemical properties of synthesized g-C3N4/ZnO composites were mainly characterized by XRD, UVâ»VIS diffuse reflectance spectroscopy (DRS), N2 adsorption-desorption, FTIR, TEM, and SEM. These nanocomposites' photocatalytic properties were evaluated in methylene blue (MB) dye photodecomposition under UV and sunlight irradiation. Interestingly, compared with ZnO nanorods, g-C3N4/ZnO nanocomposites (x:1, obtained from urea and ZnO nanorods) exhibited weak photocatalytic activity likely due to a "shading effect", while nanocomposites (x:1 CN, made from g-C3N4 and zinc acetate) showed enhanced photocatalytic activity that can be ascribed to the effective establishment of heterojunctions. A kinetics study showed that a maximum reaction rate constant of 0.1862 min-1 can be achieved under solar light illumination, which is three times higher than that of bare ZnO nanorods. The photocatalytic mechanism was revealed by determining reactive species through adding a series of scavengers. It suggested that reactive âO2- and h⺠radicals played a major role in promoting dye photodegradation.
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BACKGROUND: Intraoperative blood pressure (BP) is one of the basic vital signs monitoring. Compared with standard invasive BP measurement, TL-300 allows for a continuous and beat-to-beat noninvasive intraoperative BP monitoring. The current retrospective study compared the accuracy and precision of this noninvasive technique for continuous BP monitoring with that of standard invasive BP measurement in patients undergoing elective neurosurgery. MATERIALS AND METHODS: BP records of 23 patients undergoing elective neurosurgery, measured by both noninvasive TL-300 and invasive radial arterial catheter method, were retrospectively analyzed. Variability in BP data was analyzed by using linear regressions and Bland-Altman analysis. RESULTS: Four thousand three hundred eighty-one pairs of BP measurements from a total of 23 patients were included. The coefficient of determination of systolic, diastolic, and mean BP were 0.908, 0.803, and 0.922, respectively. And their bias was found to be 1.3±5.87 mm Hg (95% limits of agreement: -10.2 to +12.8 mm Hg), 2.8±6.40 mm Hg (95% limits of agreement: -9.8 to +15.3 mm Hg), and 1.8±4.20 mm Hg (95% limits of agreement: -6.4 to +10.1 mm Hg), respectively. CONCLUSIONS: TL-300 system is a promising noninvasive alternative to the invasive arterial catheter method for intraoperative BP monitoring, with a high accuracy and precision. With the limitation of the current retrospective study, further prospective method comparison studies are needed.