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1.
Opt Lett ; 49(9): 2353-2356, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38691717

RESUMEN

Clock recovery (CR) algorithms that support higher baud rates and advanced modulation formats are crucial for short-distance optical interconnections, and it is desirable to push CR to operate at baud rate with minimal computing resources and power. In this Letter, we proposed a hardware-efficient and multiplication operation-free baud-rate timing error detector (TED) as a solution to meet these demands. Our approach involves employing both the absolute value of samples and the nonlinear sign operation to emphasize the clock tone, which is deteriorated by severe bandwidth limitation in Nyquist and faster than Nyquist (FTN) systems. Through experimental investigations based on a transceiver system with a 3 dB bandwidth of 30 GHz, the proposed baud-rate TED exhibits excellent performance. The proposed scheme successfully achieves clock synchronization of the received signals with the transmitted signals, including 50 GBaud PAM4/8, 80 GBaud PAM4, and up to 120 GBaud PAM4 FTN signals. To the best of our knowledge, the CR based on the proposed baud-rate TED is the most optimal solution for ultrahigh-speed short-reach IM/DD transmission, comprehensively considering the timing jitter, bit error rate (BER), and implementation complexity.

2.
Anesth Analg ; 138(3): 589-597, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38100389

RESUMEN

BACKGROUND: The goal of this study was to investigate the efficacy of neostigmine on postoperative cognitive dysfunction (POCD) and determine its effect on systematic markers of oxidative stress in older patients. METHODS: This double-blind placebo-controlled trial enrolled 118 elderly patients (≥65 years) undergoing noncardiac surgeries who were allocated to a neostigmine treatment group (0.04 mg/kg) or a placebo control group (normal saline) postoperatively. POCD was diagnosed if the Z -scores for the mini-mental state examination and the Montreal Cognitive Assessment were both ≤-1.96. Postoperative serum levels of malondialdehyde (MDA), superoxide dismutase (SOD), and brain-derived neurotrophic factor (BDNF) were also compared. Multivariable regression analysis with dose adjustment of atropine was used to demonstrate the influence of neostigmine on the incidence of POCD. RESULTS: Patients receiving neostigmine had a significantly reduced incidence of POCD compared to patients who were treated with placebo on the first day after surgery (-22%, 95% confidence interval [CI], -37 to -7), but not on the third (8%, 95% CI, -4 to 20) or seventh day after surgery (3%, 95% CI, -7 to 13). Postoperative plasma MDA levels were significantly lower ( P = .016), but SOD and BDNF levels were increased ( P = .036 and .013, respectively) in the neostigmine group compared to the control group on the first day after surgery. CONCLUSIONS: Neostigmine reduced POCD on the first day after noncardiac surgery in older patients. Neostigmine treatment inhibited oxidative stress and increased serum BDNF levels. There was no significant influence of neostigmine on POCD on the third or seventh day after surgery. The clinical influence of neostigmine on POCD should be further investigated.


Asunto(s)
Disfunción Cognitiva , Complicaciones Cognitivas Postoperatorias , Anciano , Humanos , Factor Neurotrófico Derivado del Encéfalo , Disfunción Cognitiva/complicaciones , Neostigmina/efectos adversos , Complicaciones Cognitivas Postoperatorias/inducido químicamente , Complicaciones Cognitivas Postoperatorias/diagnóstico , Complicaciones Cognitivas Postoperatorias/epidemiología , Complicaciones Posoperatorias/inducido químicamente , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/epidemiología , Superóxido Dismutasa , Método Doble Ciego
3.
Appl Microbiol Biotechnol ; 106(21): 7013-7025, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36173453

RESUMEN

Flue gas not only contains carbon dioxide (CO2) but also air pollutants (sulfur oxides (SOx) and nitrogen oxides (NOx)). The effective utilization of flue gas could help us to reduce the cost of microalgal biomass production. This study assessed and explored the utilization of flue gas for the absorption characteristics of different components and their biological effect in microalgal culture systems. In abiotic absorption experiments, the absorptivity of CO2 was reduced by a maximum of 3.1%, and the concentration of the available carbon source in the culture medium was decreased by 6.7% when sulfur dioxide (SO2, at 100 mg/m3) was presented in the flue gas. Meanwhile, the presence of oxygen (O2, at 4%) in the flue gas improved the absorptivity of nitric oxide (NO). When Scenedesmus dimorphus was cultured using bisulfites and nitrites (at 10 mmol/L and 8 mmol/L, respectively) as the sulfur and nitrogen sources, SOx and NOx in the flue gas did not significantly affect growth of microalgal cells and the carbohydrate, lipid, and protein content. The consumption rates of nutrient elements were calculated, which could provide an adjustment strategy for the initial gas source when culturing microalgae with the flue gas. This study indicates that the flue gas used for microalgal culture should be partially desulfurized, so that the SOx and CO2 concentrations can optimize growth of microalgal cells, while the denitrification might not be needed since the flue gas can be oxidized to utilize the NO. KEY POINTS: • The concentration of the available carbon source in the culture medium was decreased when SO2 was presented in the flue gas, and the presence of O2 in the flue gas improved the absorptivity of NO. • An adjustment strategy for the initial gas source when culturing microalgae with the flue gas was firstly proposed. • For flue gas containing 10% CO2 and 60 mg/m3 of SO2, growth of Scenedesmus dimorphus showed no difference in cell growth in normal culture conditions.


Asunto(s)
Contaminantes Atmosféricos , Microalgas , Microalgas/metabolismo , Dióxido de Carbono/metabolismo , Dióxido de Azufre/metabolismo , Óxido Nítrico/metabolismo , Nitritos/metabolismo , Biomasa , Contaminantes Atmosféricos/metabolismo , Óxidos de Nitrógeno/metabolismo , Nitrógeno/metabolismo , Lípidos , Oxígeno/metabolismo , Carbohidratos , Azufre/metabolismo
4.
Bioprocess Biosyst Eng ; 45(11): 1879-1888, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36209452

RESUMEN

On the basis of determining isoelectric point of algae residue protein obtained from Scenedesmus dimorphus, this study investigated the effects of pH values, ratio of liquid to solid, extraction temperature and time on protein extraction rates, and assessed the nutritional value of protein extracted from microalgae residues. The results from orthogonal experiments revealed the optimum conditions for extracting proteins from algal residues (pH: 12; liquid-to-solid ratio: 40 mL/g; extraction temperature: 45 ℃; extraction time: 140 min). It was observed that under the optimal conditions, the protein extraction rate was 40.13%. Essential amino acids account for 44.3% of the proteins obtained from algal residues. The content of anti-nutritional factors in algal residues was significantly reduced, and the digestibility of algal residue proteins was higher than the digestibility of algal powder. This indicated that algal residues could be an ideal source of proteins for humans.


Asunto(s)
Microalgas , Scenedesmus , Humanos , Microalgas/metabolismo , Evaluación Nutricional , Temperatura , Scenedesmus/metabolismo , Biomasa , Biocombustibles
5.
Opt Express ; 29(22): 36242-36256, 2021 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-34809040

RESUMEN

A novel joint intra and inter-channel nonlinearity compensation method is proposed, which is based on interpretable neural network (NN). For the first time, conventional cascaded digital back-propagation (DBP) and nonlinear polarization crosstalk canceller (NPCC) are deep unfolded into an NN architecture together based on their physical meanings. Verified by extensive simulations of 7-channel 20-GBaud DP-16QAM 3200-km coherent optical transmission, deep-unfolded DBP-NPCC (DU-DBP-NPCC) achieves 1 dB and 0.36 dB Q factor improvement at the launch power of -1 dBm/channel compared with chromatic dispersion compensation (CDC) and cascaded DBP-NPCC, respectively. Under the bit error rate threshold of 2 × 10-2, DU-DBP-NPCC extends the maximum transmission reach by 28% (700 km) compared with CDC. Besides, 3 different training schemes of DU-DBP-NPCC are investigated, implying the effective signal-to-noise ratio is not the proper evaluation metric of nonlinearity compensation performance for DU-DBP-NPCC. Moreover, DU-DBP-NPCC costs 26% lower computational complexity compared with DBP-NPCC, providing a better choice for joint intra and inter-channel nonlinearity compensation in long-haul coherent systems.

6.
J Clin Pharm Ther ; 46(3): 814-819, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33462825

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Acarbose can efficiently block glucose absorption in the intestine as an alpha-glucosidase inhibitor. It is currently manufactured in several oral dosage forms, with the most common types being tablets and chewable tablets. The acarbose tablet (Glucobay® , 50 mg, Bayer) package insert gives instructions for either directly swallowing or chewing then swallowing. This study compared the pharmacodynamic effects of a single formulation of acarbose tablets under these two different administration routes. METHODS: This randomized, crossover study enrolled 24 healthy subjects who were instructed to chew (C group) or swallow (S group) the acarbose tablet. Glucose levels were monitored in subjects for up to 4 h following administration of 75 g of sucrose to establish a baseline firstly, after which subjects in the C and S groups were administered 50- or 100- mg of acarbose along with 75 g of sucrose. Then, subjects entered a 1-week washout period before being crossed over to the alternate dosing route. RESULTS AND DISCUSSION: Compared with the S group, the C group had a lower maximum concentration of serum glucose (Cmax ) and areas under the concentration-time curve (AUC0-2 , AUC0-1.5 ). In addition, the maximum reduction in serum glucose (ΔCmax ) and the reduction in the AUC (AUEC0-1.5 ) were both increased in the S group. This occurred at both the 50 mg and 100 mg dosages. These results indicate that fluctuations in blood glucose were lower following chewing of the acarbose tablet. Both administration routes exhibited similar safety and tolerance profiles. WHAT IS NEW AND CONCLUSION: In summary, chewing acarbose tablets appears to induce a superior glycaemic-controlling effect compared with swallowing them directly, at least with a single dose. It will be important to inform both clinicians and patients about these differences between the two administrations so that informed clinical decisions can be made, as numerous patients with diabetes are inclined to directly swallow acarbose tablets for convenience.


Asunto(s)
Acarbosa/administración & dosificación , Acarbosa/farmacología , Inhibidores de Glicósido Hidrolasas/administración & dosificación , Inhibidores de Glicósido Hidrolasas/farmacología , Comprimidos/química , Acarbosa/farmacocinética , Adolescente , Adulto , Área Bajo la Curva , Glucemia/efectos de los fármacos , Índice de Masa Corporal , China , Estudios Cruzados , Deglución/fisiología , Relación Dosis-Respuesta a Droga , Femenino , Inhibidores de Glicósido Hidrolasas/farmacocinética , Voluntarios Sanos , Humanos , Masculino , Masticación/fisiología , Persona de Mediana Edad , Adulto Joven
7.
BMC Surg ; 21(1): 266, 2021 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-34044830

RESUMEN

BACKGROUND: This study aimed to investigate the anesthetic effect of butorphanol with different doses in patients undergoing gastroscopy and colonoscopy. METHODS: 480 patients undergoing gastroscopy and colonoscopy were recruited and randomly divided into four groups to receive different doses of butorphanol (Group A = 2.5 µg/kg, Group B = 5 µg/kg, Group C = 7.5 µg/kg and Group D = 10 µg/kg). Butorphanol was administered 5 min before propofol infusion. The primary outcome was the incidence of body movement. Secondary outcomes were postoperative recovery time, length of stay in the Post-Anesthesia Care Unit (PACU), the total dose of propofol, and the incidence of intraoperative hypoxemia, propofol injection pain, cough, postoperative nausea and vomiting, drowsiness, and dizziness. RESULTS: The incidence of body movement and the dose of propofol in Group C and D were lower than those in Group A and B (P < 0.05). The incidence and intensity of propofol injection pain and the incidence of cough in Group B, C, and D were lower than those in Group A (P < 0.05). The length of stay in PACU and the incidence of postoperative drowsiness and dizziness were higher in Group D than in Group A, B, and C (P < 0.05). CONCLUSION: Intravenous pre-injection of 7.5 µg/kg butorphanol with propofol can be the optimal dosage for patients undergoing gastroscopy and colonoscopy. TRIAL REGISTRATION: Trial registration: Chinese Clinical Trial Registry, ChiCTR2000031506. Registered 3 April 2020-Retrospectively registered, http://www.medresman.org.cn .


Asunto(s)
Anestésicos , Propofol , Butorfanol , Colonoscopía , Gastroscopía , Humanos
8.
Bioprocess Biosyst Eng ; 44(9): 1901-1912, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33864126

RESUMEN

Carbon dioxide supplementation is significant for cell growth in autotrophic cultures of microalgae. However, the CO2 utilization efficiency is quite low in most processes. Aimed at this problem, six kinds of physical absorption enhancers were investigated to enhance the biological carbon sequestration of microalgae. By the addition of a small amount of CO2 absorption enhancer, the total inorganic carbon concentration of the medium was significantly increased. In addition, the biomass productivity of Scenedesmus dimorphus was maximally increased by 63% by the addition of propylene carbonate in flask cultures. In cultures using an air-lift photobioreactor equipped with a pH-feedback control system to supply CO2, the CO2 consumption was maximally reduced by 71% with added polyethylene glycol dimethyl ether. This study indicates that the incorporation of physical absorption enhancers could be a promising approach to overcome the problems of low CO2 utilization efficiency and high carbon source cost in algal biomass production.


Asunto(s)
Dióxido de Carbono/metabolismo , Microalgas/crecimiento & desarrollo , Fotobiorreactores , Scenedesmus/crecimiento & desarrollo , Concentración de Iones de Hidrógeno
9.
BMC Geriatr ; 20(1): 387, 2020 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-33023491

RESUMEN

BACKGROUND: Postoperative cognitive dysfunction is a common postoperative complication in elderly patients. In elderly patients, the decline of organ function and neuromuscular junction function make them more sensitive to muscle relaxants. They are more likely to experience residual muscle relaxation after surgery, which may cause various adverse events. Neostigmine, a commonly used muscle relaxant antagonist, can reduce the expression of inflammatory factors, thereby reducing the pro-inflammatory response and neurodegeneration of the cerebral cortex and hippocampus after surgery. The study aimed at observing the effect of different doses of neostigmine on postoperative cognitive function and peripheral inflammatory factors in elderly patients. METHODS: One hundred thirty-two elderly patients who underwent a radical section of gastrointestinal cancer at First Affiliated Hospital of Dalian Medical University were divided into neostigmine and saline groups at a 2:1 ratio. Neostigmine was intravenously injected in the post-anesthesia care unit (PACU) according to the train-of-four ratio (TOFR) T4/T1. When TOFR was ≤0.5, 0.04 mg/kg neostigmine was administered, whereas when TOFR was > 0.5, 0.02 mg/kg neostigmine was injected. The main observation indexes were cognitive function, interleukin 1 beta (IL-1ß), tumor necrosis factor-alpha (TNF-α), and interleukin 6 (IL-6) in peripheral blood at the different times before and after the surgery. Secondary observation indicators include the number of atropine injection, extubating time, PACU residence time, incidence of hypoxemia, hypercapnia, and postoperative nausea and vomiting in PACU, time of exhaustion, and length of hospitalization. RESULTS: The extubating and PACU times in 0.04 mg/kg and 0.02 mg/kg groups were significantly shorter than those in the control group (P < 0.001). The incidence of early postoperative cognitive decline in 0.04 mg/kg and 0.02 mg/kg groups was 10 and 15.7%, respectively, which were significantly lower than those in the control group (P = 0.013). CONCLUSION: In elderly patients, 0.02-0.04 mg/kg neostigmine could significantly reduce the incidence of early postoperative cognitive decline without affecting peripheral inflammatory factors. TRIAL REGISTRATION: Trial registration: Chinese Clinical Trial Registry, ChiCTR2000031739. Registered 8 April 2020 - Retrospectively registered, http://www.medresman.org.cn .


Asunto(s)
Bloqueo Neuromuscular , Fármacos Neuromusculares no Despolarizantes , Anciano , Inhibidores de la Colinesterasa/efectos adversos , Cognición , Humanos , Neostigmina/efectos adversos , Complicaciones Posoperatorias
10.
Opt Express ; 27(18): 25708-25717, 2019 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-31510438

RESUMEN

In this paper, a memory polynomial equalizer combined with decision feedback equalizer (MPE-DFE) is proposed to eliminate channel distortions for intensity modulation and direct detection (IM/DD) systems. Compared with traditional feedforward equalizer and decision feedback equalizer (FFE-DFE), the proposed MPE-DFE introduces extra square terms and cubic terms to jointly equalize chromatic dispersion and nonlinear distortions. We demonstrated a C-band 56-Gb/s four-level pulse-amplitude modulation (PAM4) system over 80-km standard single mode fiber (SSMF) transmission. Experimental results show that the proposed MPE-DFE achieved up to 6.2 dB higher SNR than traditional FFE-DFE. Moreover, the achieved bit error ratio (BER) with MPE-DFE reaches 3.1 × 10-3, which is below 7% feedforward error correction (FEC) threshold of 3.8 × 10-3. To the best of our knowledge, we achieved a record transmission distance for C-band 56-Gb/s PAM4 signal with only electrical equalization at the receiver.

11.
Bioprocess Biosyst Eng ; 37(10): 2073-82, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24728965

RESUMEN

Microalgal lipid induction through nitrogen stress often suffers from a contradiction between biomass productivity and lipid content, i.e., either high biomass productivity with low lipid content or vice versa. A two-stage nitrogen-replete and nitrogen-deplete (NR-ND) culture was suggested to be an option to attain high lipid productivity. In this study, the effects of culture conditions and modes on biomass productivity and lipid productivity of Nannochloropsis sp. in the two stages were comprehensively investigated. The optimal culture conditions for the two stages, aiming to high biomass productivity and lipid productivity respectively, were consistent, i.e., CO2 content in aeration (1 %), phosphorus concentration in medium (181 µmol/L), incident light intensity (150 µE/(m(2)s)), temperature (25 °C). Different culture modes of the two stages were compared. The overall lipid productivity of the two-stage continuous-batch mode achieved 0.123 g/(L day), which was 60.3, 48.2, 34.9 and 13.5 % higher than that of single nitrogen-replete batch, single nitrogen-limited batch, continuous nitrogen-replete culture and two-stage batch-batch culture, respectively, and also higher than most reported values. This contribution provides fundamental data for the two-stage NR-ND cultivation process design of Nannochloropsis sp.


Asunto(s)
Lípidos/biosíntesis , Estramenopilos/metabolismo , Biomasa , Reactores Biológicos , Medios de Cultivo , Estramenopilos/citología
12.
Front Nutr ; 11: 1455553, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39296509

RESUMEN

Spirulina is capable of using light energy and fixing carbon dioxide to synthesize a spectrum of organic substances, including proteins, polysaccharides, and unsaturated fatty acids, making it one of the most coveted food resources for humanity. Conventionally, Spirulina products are formulated into algal powder tablets or capsules. However, the processing and preparation of these products, involving screw pump feeding, extrusion, high-speed automation, and high-temperature dewatering, often result in the rupture of cell filaments, cell fragmentation, and the unfortunate loss of vital nutrients. In contrast, fresh Spirulina, cultivated within a closed photobioreactor and transformed into an edible delight through harvesting, washing, filtering, and sterilizing, presents a refreshing taste and odor. It is gradually earning acceptance as a novel health food among the general public. This review delves into the manufacturing processes of fresh Spirulina, analyzes its nutritional advantages over conventional algal powder, and ultimately prospects the avenues for fresh Spirulina's application in modern food processing. The aim is to provide valuable references for the research and development of new microalgal products and to propel the food applications of microalgae forward.

13.
Sheng Wu Gong Cheng Xue Bao ; 39(2): 488-499, 2023 Feb 25.
Artículo en Zh | MEDLINE | ID: mdl-36847085

RESUMEN

Microplastics pollution has attracted worldwide attention. Compared with the status quo of microplastics pollution in marine environment and other major rivers and lakes, the relevant data of the Yellow River basin is relatively inadequate. The abundance, types, and spatial distribution characteristics of microplastic pollution in the sediments and surface water of the Yellow River basin were reviewed. Meanwhile, the status of microplastic pollution in the national central city and Yellow River Delta wetland was discussed, and the corresponding prevention and control measures were put forward. The results showed that the spatial distribution of microplastics pollution in sediments and surface water of the Yellow River basin increased from upstream to downstream, especially in the Yellow River Delta wetland. There are obvious differences between the types of microplastics in sediment and surface water in the Yellow River basin, which is mainly related to the materials of microplastics. Compared with similar regions in China, the microplastics pollution levels in national key cities and national wetland parks in the Yellow River basin are in the medium to high degree, which should be taken seriously. Plastics exposure through various ways will cause serious impact on aquaculture and human health in the Yellow River beach area. To control microplastic pollution in the Yellow River basin, it is necessary to improve the relevant production standards, laws and regulations, and improve the capacity of biodegradable microplastics and the degradation capacity of plastic wastes.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Humanos , Plásticos , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Agua , China
14.
World J Clin Cases ; 11(32): 7806-7813, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-38073686

RESUMEN

BACKGROUND: Postoperative nausea and vomiting (PONV) are common complications that affect the recovery and well-being of elderly patients undergoing gastrointestinal laparoscopic surgery. AIM: To investigate the effect of butorphanol on PONV in this patient population. METHODS: A total of 110 elderly patients (≥ 65 years old) who underwent gastrointestinal laparoscopic surgery were randomly assigned to receive butorphanol (40 µg/kg) or sufentanil (0.3 µg/kg) during anesthesia induction in a 1:1 ratio. The measured outcomes included the incidence of PONV at 48 h after surgery, intraoperative dose of propofol and remifentanil, Bruggrmann Comfort Scale score in the postanesthesia care unit (PACU), number of compressions for postoperative patient-controlled intravenous analgesia (PCIA), and time to first flatulence after surgery. RESULTS: The results revealed a noteworthy reduction in the occurrence of PONV at 24 h after surgery in the butorphanol group, when compared to the sufentanil group (T1: 23.64% vs 5.45%, T2: 43.64% vs 20.00%, P < 0.05). However, no significant variations were observed between the two groups, in terms of the clinical characteristics, such as the PONV or motion sickness history, intraoperative and postoperative 48-h total infusion volume and hemodynamic parameters, intraoperative dose of propofol and remifentanil, number of postoperative PCIA compressions, time until the first occurrence of postoperative flatulence, and incidence of PONV at 48 h post-surgery (all, P > 0.05). Furthermore, patients in the butorphanol group were more comfortable, when compared to patients in the sufentanil group in the PACU. CONCLUSION: The present study revealed that butorphanol can be an efficacious substitute for sufentanil during anesthesia induction to diminish PONV within 24 h following gastrointestinal laparoscopic surgery in the elderly, simultaneously improving patient comfort in the PACU.

15.
World J Clin Cases ; 11(3): 610-620, 2023 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-36793626

RESUMEN

BACKGROUND: Propofol is a short-acting, rapid-recovering anesthetic widely used in sedated colonoscopy for the early detection, diagnosis and treatment of colon diseases. However, the use of propofol alone may require high doses to achieve the induction of anesthesia in sedated colonoscopy, which has been associated with anesthesia-related adverse events (AEs), including hypoxemia, sinus bradycardia, and hypotension. Therefore, propofol co-administrated with other anesthetics has been proposed to reduce the required dose of propofol, enhance the efficacy, and improve the satisfaction of patients receiving colonoscopy under sedation. AIM: To evaluate the efficacy and safety of propofol target-controlled infusion (TCI) in combination with butorphanol for sedation during colonoscopy. METHODS: In this controlled clinical trial, a total of 106 patients, who were scheduled for sedated colonoscopy, were prospectively recruited and assigned into three groups to receive different doses of butorphanol before propofol TCI: Low-dose butorphanol group (5 µg/kg, group B1), high-dose butorphanol group (10 µg/kg, group B2), and control group (normal saline, group C). Anesthesia was achieved by propofol TCI. The primary outcome was the median effective concentration (EC50) of propofol TCI, which was measured using the up-and-down sequential method. The secondary outcomes included AEs in perianesthesia and recovery characteristics. RESULTS: The EC50 of propofol for TCI was 3.03 µg/mL [95% confidence interval (CI): 2.83-3.23 µg/mL] in group B2, 3.41 µg/mL (95%CI: 3.20-3.62 µg/mL) in group B1, and 4.05 µg/mL (95%CI: 3.78-4.34 µg/mL) in group C. The amount of propofol necessary for anesthesia was 132 mg [interquartile range (IQR), 125-144.75 mg] in group B2 and 142 mg (IQR, 135-154 mg) in group B1. Furthermore, the awakening concentration was 1.1 µg/mL (IQR, 0.9-1.2 µg/mL) in group B2 and 1.2 µg/mL (IQR, 1.025-1.5 µg/mL) in group B1. Notably, the propofol TCI plus butorphanol groups (groups B1 and B2) had a lower incidence of anesthesia AEs, when compared to group C. Furthermore, no significant differences were observed in the rates of AEs in perianesthesia, including hypoxemia, sinus bradycardia, hypotension, nausea and vomiting, and vertigo, among group C, group B1 and group B2. CONCLUSION: The combined use with butorphanol reduces the EC50 of propofol TCI for anesthesia. The decrease in propofol might contribute to the reduced anesthesia-related AEs in patients undergoing sedated colonoscopy.

16.
Front Bioeng Biotechnol ; 10: 1072942, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36532587

RESUMEN

During the heterotrophic cultivation of microalgae, a cooled process against temperature rise caused by the metabolism of exogenous organic carbon sources greatly increases cultivation cost. Furthermore, microalgae harvesting is also a cost-consuming process. Cell harvesting efficiency is closely related to the characteristics of the algal cells. It may be possible to change cell characteristics through controlling culture conditions to make harvesting easier. In this study, the mesophilic Chlorella pyrenoidosa was found to be a thermal-tolerant species in the heterotrophic mode. The cells could maintain their maximal specific growth rate at 40°C and reached 1.45 day-1, which is equivalent to that of cultures at 35°C but significantly higher than those cultured at lower temperatures. Interestingly, the cells cultured at 40°C were much easier to be harvested than those at lower temperatures. The harvesting efficiency of the cells cultured at 40°C reached 96.83% after sedimentation for 240 min, while the cells cultured at lower temperatures were reluctant to settle. Likely, the same circumstance occurred when cells were harvested by centrifugation or flocculation. The promotion of cell harvesting for cells cultured at high temperatures was mainly attributed to increased cell size and decreased cell surface charge. To the best of our knowledge, this is the first report that cells cultured at high temperatures can promote microalgae harvesting. This study explores a new approach to simplify the cultivation and harvesting of microalgae, which effectively reduces the microalgae production cost.

17.
J Biosci Bioeng ; 132(4): 365-371, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34344605

RESUMEN

Microalgae are natural, green raw material and could be used for the development of edible oil for its abundant polyunsaturated fatty acids, with fast growth rate. The wet mud and dry powder of Scenedesmus dimorphus were applied to compare the extraction effects of different organic solvent systems in this study. The results displayed that, by using the ethanol/n-hexane (3:2, v/v) mixed solvent, the oil extraction rate from wet algal mud was 68.31 %, with 71.65 % of neutral lipid, and 1.87 % of vitamin E; the retention rates of protein, chlorophyll, and carbohydrates in the algal residue after oil extraction were 60.56 %, 53.27 %, and 80.20 %, respectively. Through the single solvent n-hexane, the oil extraction rate from dried algal powder was 71.52 %, with 75.86 % of neutral lipids, and 1.63 % of vitamin E. The retention rates of protein, chlorophyll, and carbohydrate were 55.92 %, 61.33 % and 78.35 %, respectively, suggesting the high rate of nutrient retention. In addition, the orthogonal experiments indicated that the compound of low concentration natural antioxidants with 0.010 % of tea polyphenols, 0.005 % of vitamin E, and 0.015 % of rosemary extract had the best effects on improvement of oxidative stability.


Asunto(s)
Microalgas , Biomasa , Aceites , Estrés Oxidativo , Solventes
18.
Appl Biochem Biotechnol ; 187(4): 1488-1501, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30259410

RESUMEN

This work investigated the cultivation of Chlorella vulgaris in a thin-film flat plate photobioreactor under outdoor conditions and using digested piggery wastewater as the culture medium. The algal cells were able to adapt quickly to the wastewater and outdoor conditions. A specific growth rate of 0.12 day-1 was obtained in the exponential growth phase, which was slightly higher than that during indoor cultivation using artificial culture medium. Results showed that Chlorella vulgaris effectively removed TN, TP, and COD by 72.48%, 86.93%, and 85.94%. Due to the difference in culture conditions and phosphorus availability, the biomass from outdoor cultivation contained higher lipid content and more unsaturated fatty acids compared to indoor cultures, while the amino acid composition was unaffected. Results of metallic element assay indicated that the biomass cultured with wastewater conformed to the standards required for animal feed additive production. The overall cost of the biomass production in the thin-film flat plate photobioreactor (32.94 US$/kg) was estimated to be 4.67 times lower than that of indoor cultivation (154.04 US$/kg). Together, these results provide a basis for large-scale outdoor production of microalgae and wastewater bioremediation.


Asunto(s)
Microalgas/metabolismo , Nutrientes/aislamiento & purificación , Nutrientes/metabolismo , Fotobiorreactores/microbiología , Aguas Residuales/química , Animales , Biomasa , Técnicas de Cultivo , Porcinos
19.
J Neurosurg Anesthesiol ; 30(1): 59-64, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27820300

RESUMEN

BACKGROUND: Neonatal mice exposed to sevoflurane show certain cognitive and behavioral impairments in adulthood. However, the mechanisms underlying long-term cognitive deficits induced by sevoflurane exposure remain unknown. The present study was performed to investigate whether there is differential neuronal activation between naive mice and sevoflurane-exposed neonates in fear-conditioning tests based on immediate early gene (c-Fos) expression. METHODS: Male mice were exposed to 3% sevoflurane (SEVO group) or carrier gas alone (no anesthesia, NA group) for 6 hours on postnatal day 6. The mice were allowed to mature before performing the contextual fear-conditioning test. A reduced freezing response was confirmed in the SEVO group. Neural activation in the regions of the medial prefrontal cortex, hippocampus, and amygdala was investigated using c-Fos immunostaining 2 hours after the test. The types of neurons activated were also identified. RESULTS: The number of c-Fos-positive cells decreased by 27% in the basolateral amygdala in the SEVO group, while no significant changes were observed in other regions. Furthermore, glutamatergic, but not γ-aminobutyric acid (GABA)ergic, neurons expressed c-Fos after the contextual fear-conditioning test in both groups. The number of glutamatergic neurons in the basolateral amygdala in the SEVO group was reduced by 27%. CONCLUSIONS: Decreased neural activation in the basolateral amygdala may be associated with reduced freezing time in neonatal sevoflurane-exposed mice. Fewer glutamatergic neurons responding to fear stimuli in the basolateral amygdala may contribute to decreased neural activation and learning deficits in mice exposed to sevoflurane as neonates.


Asunto(s)
Anestésicos por Inhalación/efectos adversos , Complejo Nuclear Basolateral/patología , Miedo/psicología , Glutamatos , Discapacidades para el Aprendizaje/inducido químicamente , Discapacidades para el Aprendizaje/psicología , Éteres Metílicos/efectos adversos , Neuronas/patología , Animales , Animales Recién Nacidos , Análisis de los Gases de la Sangre , Recuento de Células , Condicionamiento Psicológico , Genes fos/efectos de los fármacos , Discapacidades para el Aprendizaje/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Sevoflurano , Ácido gamma-Aminobutírico/metabolismo
20.
Exp Anim ; 67(2): 193-200, 2018 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-29187700

RESUMEN

Systemic inflammation induces brain neuronal inflammation, in turn causing acute cognitive disorders. Furthermore, neuronal inflammation is one cause of postoperative cognitive disorder (POCD) and delirium. However, no sufficiently established pharmacological treatment is available for neurocognitive inflammation. This study evaluated the possible neuroprotective effects of preconditioning with sevoflurane anesthesia on cognition and neuroinflammatory changes in an animal model of lipopolysaccharide (LPS)-induced systemic inflammation. Adult mice were randomly divided into (1) control, (2) 2% sevoflurane preconditioning for 1 h, (3) intraperitoneal 5 mg/kg LPS injection, and (4) 2% sevoflurane preconditioning for 1 h + LPS injection groups. At 24 h after 5 mg/kg LPS injection, microglial activation based on ionized calcium-binding adapter molecule 1 (Iba-1) expression in the hippocampus was determined using immunostaining and immunoblotting. IL-1ß and IL-6 immunoblotting were used as inflammation markers, and ß-site of amyloid precursor protein cleaving enzyme 1 (BACE1) immunoblotting was performed to evaluate amyloid ß-protein (Aß) accumulation. Long-term cognitive impairment was evaluated using fear conditioning tests. Intraperitoneal LPS increased levels of Iba-1 (150%), inflammation markers (160%), and Aß accumulation (350%), and sevoflurane preconditioning suppressed these increases. Systemic LPS caused learning deficits. Sevoflurane also maintained long-term memory in mice receiving LPS injection. Sevoflurane preconditioning prevented long-term memory impairment in the mouse model administered systemic LPS by decreasing excessive microglial activation, inflammation, and Aß accumulation. This study supports the hypothesis that sevoflurane preconditioning might also be beneficial for neuronal inflammation. Sevoflurane might be beneficial for reducing delirium and POCD.


Asunto(s)
Disfunción Cognitiva/inducido químicamente , Disfunción Cognitiva/prevención & control , Lipopolisacáridos/efectos adversos , Éteres Metílicos/uso terapéutico , Complicaciones Posoperatorias/prevención & control , Péptidos beta-Amiloides/metabolismo , Animales , Delirio/inducido químicamente , Delirio/prevención & control , Modelos Animales de Enfermedad , Inflamación/inducido químicamente , Inflamación/prevención & control , Inyecciones Intraperitoneales , Lipopolisacáridos/administración & dosificación , Masculino , Éteres Metílicos/farmacología , Ratones Endogámicos C57BL , Fármacos Neuroprotectores , Sevoflurano
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