Effect of anesthesia induction with butorphanol on postoperative nausea and vomiting: A randomized controlled trial.

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.

Efficacy and safety of propofol target-controlled infusion combined with butorphanol for sedated colonoscopy.

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.

Thermal-tolerant potential of ordinary Chlorella pyrenoidosa and the promotion of cell harvesting by heterotrophic cultivation at high temperature.

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.

Mass transfer characteristics and effect of flue gas used in microalgae culture.

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.

Selection of extraction solvents for edible oils from microalgae and improvement of the oxidative stability.

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.

Enhancing CO2 utilization by a physical absorption-based technique in microalgae culture.

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.

Microalgal Cultivation and Nutrient Removal from Digested Piggery Wastewater in a Thin-film Flat Plate Photobioreactor.

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.

Nanomedicine-based paclitaxel induced apoptotic signaling pathways in A562 leukemia cancer cells.

In the present study, we have synthesized an amphiphilic pH-sensitive structure of poly(ethylene glycol) methyl ether-b-(poly lactic acid-co-poly(b-amino esters)) (MPEG-b-(PLA-co-PAE)) to load paclitaxel to increase the therapeutic efficacy in leukemia. The micelles exhibit excellent drug-loading capacities for paclitaxel (PTX) and exhibited a typical pH-responsive drug release pattern. The release of PTX from the micelles was significantly accelerated by decreasing pH from 7.4 to 5.0 which just fitted the pathological process. The most important advantage of this design is that the polymeric micelles provide an effective approach for rapid transport of cargo into the cytosol, which significantly increases the antitumor efficacy of PTX against K562 cancer cells. Paclitaxel-loaded polymer micelles (PTX-M) showed significantly higher cytotoxic effect than that of free PTX. The PTX-M exhibited a superior apoptosis effect in cancer cells compared to that of free PTX at all time points. We have showed that the PTX-M activated upstream of apoptosis signaling and inhibited the anti-apoptotic factors. The PTX-M remarkably increased the upregulation of Bax, caspase-3, caspase-9, and PARP-1 expression and downregulated the Bcl-2 expression in K562 cancer cells. The results show that PTX-M induced cell apoptosis through intrinsic apoptotic signaling pathway. Importantly, PTX had a remarkably prolonged plasma circulation time after administration of PTX-M. Overall, this novel cancer specific, pH-responsive, and potentially in vivo stable unimolecular micelles may provide a very promising approach for targeted cancer therapy in the effective treatment of Leukemia.

Transferrin-conjugated polymeric nanomedicine to enhance the anticancer efficacy of edelfosine in acute myeloid leukemia.

In this study, transferrin (Tf)-conjugated polyethylene glycol (PEG)-poly-l-lysine (PLL)-poly(lactic-co-glycolic acid) (PLGA) (PEG-PLL-PLGA)-based micellar formulations were successfully prepared for the delivery of edelfosine (EDS) in leukemia treatment. The micelles were nanosized and presented spherical shaped particles. Our in vitro data suggest that the nanoformulations maintain the biological activity of drugs for longer periods and lead to a continuous release of active drug. The enhanced cellular uptake of EDS-TM resulted in significantly higher cytotoxic effect in K562 leukemia cells. Cell cycle analysis further demonstrated the significantly higher G2/M phase arrest of cancer cells. Immunoblot analysis clearly revealed the potential of EDS-TM in inducing apoptosis of cancer cells which could improve the anticancer efficacy in leukemia. Importantly, EDS-M and EDS-TM significantly prolonged the circulation profile of EDS throughout until 24h, indicating the potential of targeted nanoparticulate delivery system. The prolonged blood circulation potential of micellar formulations might improve the therapeutic potential of drug by increasing its bioavailability in the serum. It would be worthwhile evaluating the effects of the EDS-loaded micelles on cancer cells in vivo for clinical application.