Effects of blood components of preoperative autologous blood donation on functions of myelopoietic stem cells.

OBJECTIVE: To explore the effects of preoperative autologous whole blood donation and autologous pure red blood cell (RBC) donation on hematopoietic stem cells (HSC), clarify the effects of transfusion by different blood components on HSC, and improve the treatment effect of autotransfusion. METHODS: Forty healthy male New Zealand rabbits were divided into five groups (n = 8) at random: control (Group A), surgery alone (Group B), surgery + blood sampling (Group C), surgery + preoperative autologous whole blood autotransfusion (Group D), and surgery + preoperative autologous pure RBC autotransfusion (Group E). The rabbits' bone marrow was collected before surgery (T1), 6 h after surgery (T2), and 24 h after surgery (T3) to detect the CD34+ cell count, the reactive oxygen species (ROS) concentration, the ratio of senescent cells, and the expression of HSC-related proteins (p53 and p21). RESULTS: Compared with groups A and B, the percentage of CD34+ cells in groups D and E at each time point was significantly increased, while the proportion of senescent cells, ROS, p53 and p21 were significantly decreased (P<0.05). Compared with Group C, the percentage of CD34+ cells at T2 and T3 rose significantly, while the ratio of senescent cells, the ROS concentration, and the content of p53 and p21 declined significantly in Groups D and E (P < 0.05). Compared with Group D, the ratio of senescent cells at T2 declined significantly, the percentage of CD34+ cells at T3 rose significantly, and the ROS concentration at T2 and T3 declined significantly in Group E (P < 0.05). CONCLUSION: From the perspective of HSC, collection and transfusion of pure RBC is more beneficial to postoperative recovery of patients than whole blood transfusion.

International tourism and business productivity: does eco-friendly technologies matter?

This research is aimed at determining whether eco-friendly technologies go beyond and above in providing business productivity in international tourism. For this, the study obtained data from different databases, and this data range consisted of 2010-2020. The study applied the co-integration analysis, random and static technique, regression analysis technique, split analysis technique, and mediating effect tests on Chinese data. This research shows that tourism business innovation contributed 12%, value proposition as 9%, internal marketing as 16%, customer relationship management as 19.3%, tourists motivation as 34.05%, tourists time as 18.94%, green technological adoption as 17.3%, tourists visit intention as 8.11%, and green technical transfer as 28.1% in study model. Thus, the findings confirmed that international tourism and business productivity have a dynamic empirical nexus with the mediating role of eco-friendly technology adoption. Furthermore, such findings are robust empirically and validate the empirical connections among the study variables. These results imply that Chinese tourism industry stakeholders may use eco-friendly technologies to good effect, significantly enhancing tourism business productivity, international tourists' satisfaction, and tourists' revisit intentions. Hence, the study also directs practical implications related to the study topicality and China's tourism industry for prudent growth acquisition.

Particle swarm optimization algorithm with Gaussian exponential model to predict daily and monthly global solar radiation in Northeast China.

Reliable global solar radiation (Rs) information is crucial for the design and management of solar energy systems for agricultural and industrial production. However, Rs measurements are unavailable in many regions of the world, which impedes the development and application of solar energy. To accurately estimate Rs, particle swarm optimization (PSO) algorithm integrating Gaussian exponential model (GEM) was proposed for estimating daily and monthly global Rs in Northeast China. The PSO-GEM was compared with four other machine learning models and two empirical models to assess its applicability using daily meteorological data from 1997 to 2016 from four stations in Northeast China. The results showed that in different stations, the PSO-GEM with full climatic data as inputs showed the highest accuracy to estimate daily Rs with RMSE, RRMSE, MAE, R2, and Ens values of 1.045-1.719 MJ m-2 d-1, 7.6-12.7%, 0.801-1.283 MJ m-2 d-1, 0.953-0.981, and 0.946-0.977, respectively. The PSO-GEM showed the highest accuracy to estimate monthly Rs with RMSE, RRMSE, MAE, R2, and Ens values of 0.197-0.575 MJ m-2 d-1, 1.5-7.0%, 0.137-0.499 MJ m-2 d-1, 0.999-1, and 0.992-0.999, respectively. Overall, the PSO-GEM had the highest accuracy under different inputs and is recommended for modeling daily and monthly Rs in Northeast China.

The effect of different storage times on the oxygen-carrying capacity of the exosomes of red blood cells.

BACKGROUND: After storing blood for a period of time, the structure and properties of the red blood cells (RBC) will change, which results in a decrease in the oxygen-carrying capacity, and further has a certain impact on their exosomes. OBJECTIVES: Effective oxygen uptake (Q), P50, 2,3-DPG, and Na+-K+-ATP of RBC after different storage times were detected. Electron microscopy was used to observe the morphology of RBC and the characteristics of secreting exosomes. Western blot was used to detect the expression of phenotypes CD63 and CD81 of exosomes, and the expression of mitochondrial riboprotein MRPS35 of exosomes was also detected to explore the mechanism of decreased function of RBC with the extension of preservation time. MATERIAL AND METHODS: After the RBC suspension was prepared, the effective oxygen-carrying capacity (Q) and P50, as well as 2,3-DPG and Na+-K+-ATP were prepared. This was followed by morphology observation of erythrocyte exosomes using transmission electron microscope (TEM), and by western blot analysis of exosome phenotypes CD63 and CD81. RESULTS: Erythrocytes secrete exosomes, which results in abnormal expression of related proteins in mitochondria. This leads to increased ROS production, mitochondrial apoptosis and, finally, changes in or damage to erythrocytes. CONCLUSIONS: Changes in the rheological properties and oxygen-carrying functions of erythrocytes during preservation are all observable manifestations, and underlying these manifestations are mechanisms of damage to erythrocytes at a molecular level. Erythrocytes secrete exosomes, which results in abnormal expression of related proteins in mitochondria, increasing ROS production, mitochondrial apoptosis and, finally, changes or damage to erythrocytes.

Significant improvement in catalytic activity and enantioselectivity of a Phaseolus vulgaris epoxide hydrolase, PvEH3, towards ortho-cresyl glycidyl ether based on the semi-rational design.

The investigation of substrate spectrum towards five racemic (rac-) aryl glycidyl ethers (1a-5a) indicated that E. coli/pveh3, an E. coli BL21(DE3) transformant harboring a PvEH3-encoding gene pveh3, showed the highest EH activity and enantiomeric ratio (E) towards rac-3a. For efficiently catalyzing the kinetic resolution of rac-3a, the activity and E value of PvEH3 were further improved by site-directed mutagenesis of selected residues. Based on the semi-rational design of an NC-loop in PvEH3, four single-site variants of pveh3 were amplified by PCR, and intracellularly expressed in E. coli BL21(DE3), respectively. E. coli/pveh3E134K and /pveh3T137P had the enhanced EH activities of 15.3 ± 0.4 and 16.1 ± 0.5 U/g wet cell as well as E values of 21.7 ± 1.0 and 21.2 ± 1.1 towards rac-3a. Subsequently, E. coli/pveh3E134K/T137P harboring a double-site variant gene was also constructed, having the highest EH activity of 22.4 ± 0.6 U/g wet cell and E value of 24.1 ± 1.2. The specific activity of the purified PvEH3E134K/T137P (14.5 ± 0.5 U/mg protein) towards rac-3a and its catalytic efficiency (kcat/Km of 5.67 mM-1 s-1) for (S)-3a were 1.7- and 3.54-fold those (8.4 ± 0.3 U/mg and 1.60 mM-1 s-1) of PvEH3. The gram-scale kinetic resolution of rac-3a using whole wet cells of E. coli/pveh3E134K/T137P was performed at 20 °C for 7.0 h, producing (R)-3a with 99.4% ees and 38.5 ± 1.2% yield. Additionally, the mechanism of PvEH3E134K/T137P with remarkably improved E value was analyzed by molecular docking simulation.

Effect of Acute Normovolemic Hemodilution Combined with Controlled Low Central Venous Pressure on Blood Coagulation Function and Blood Loss in Patients Undergoing Resection of Liver Cancer Operation.

BACKGROUND/AIMS: This paper aims to investigate the effect of acute normovolemic hemodilution (ANH) used with controlled low central venous pressure (LCVP) technology on perioperative bleeding and coagulation in hepatocellular carcinoma operation patients. METHODOLOGY: A total of 60 cases undergoing hepatic resection operation were randomly divided into the control group, LCVP group (Group II), and ANH + LCVP group (Group III). The changes of hemodynamic indexes at different time points in each group were observed and recorded, along with the volume of allogenous blood transfusion and the number of patients undergoing allogenous blood transfusion. RESULTS: Compared with Group I (control), there was evident reduction of the bleeding volume, allogenic blood transfusion volume, and number of patients undergoing allogenic blood transfusion in Groups II and III. CONCLUSION: The application of ANH combined with LCVP in hepatic resection can evidently reduce intraoperative hemorrhages and homologous blood transfusions; moreover, it has no significant adverse effect on the coagulation function.

Effects of intrathecal anesthesia with different concentrations and doses on spinal cord, nerve roots and cerebrospinal fluid in dogs.

OBJECTIVE: To investigate the effects of intrathecal anesthesia with bupivacaine, levobupivacaine and ropivacaine hydrochloride at different doses on the spinal cord, nerve roots and cerebrospinal fluid (CSF) in dogs. METHODS: Forty-two mongrel dogs were randomly divided into normal saline group (C; 2 ml), 0.5% (B1) and 0.75% (B2) bupivacaine hydrochloride groups (2 ml), 0.5% (L1) and 0.75% (L2) levobupivacaine hydrochloride group (2 ml), 0.5% (R1) and 0.75% (R2) ropivacaine hydrochloride group (2 ml), and drugs were intrathecally injected. RESULTS: The contents of Ca(2+) and MDA and SOD activity of the spinal cord were comparable among groups (P > 0.05). In Groups B1, L1 and R1, the neuronal cytoplasm of spinal tissues was basically normal, the majority of mitochondria and endoplasmic reticulum had complete structure, and the lamellar structure of modulated fibers was nearly normal. In Groups B2, L2 and R2, a small amount of mitochondrial vacuolar degeneration was found in the neuronal cytoplasm of spinal cord, but their structures were basically normal; the neural tissues exhibited focal mild edema, and most of the lamellar structure of modulated fibers and Schwann cells were nearly normal except for loose structure in several fibers and cells. CONCLUSION: When compared with 0.75% anesthetics for local anesthesia, the early adverse effects on the ultrastructure of the spinal cord and nerve root reduce after focal anesthesia with 0.5% anesthetics.

Cross-sectional study of the ophthalmological effects of carbon disulfide in Chinese viscose workers.

This article presents cross-sectional investigation results of ophthalmological effects for the occupational exposure to carbon disulfide of workers at a large viscose fibre factory in the middle part of China. The total of 271 exposed subjects (191 males, 80 females) and 133 workers (93 males, 40 females) not exposed to any toxic agent in the working environment underwent ophthalmological examination. The self-administered questionnaire collected data on the medical history and ophthalmological complaints during the past three months. The ophthalmologic examination included routine examination for retinal capillary anomalies and and color vision with the FM 100-Hue test method. Nearly all subjects did not use respirators, smocks or aprons, gloves or other personal protective devices during work time. The average personal CS2 exposure level in the present study was 13.7-20.05 mg/m3. The FM 100-Hue test results showed that the total error scores of the exposed group, whether male or female, were higher than that of the control, the discrimination of the green and blue zones was also impaired significantly. A fundus examination showed no retinal capillary anomalies or other serious ophthalmological symptoms that may be related to effects of CS2. In conclusion, color vision was disturbed in workers exposed to CS2, at levels below the present threshold value. Reduced color discrimination may be attributed to long-term carbon disulfide exposure and suggests that health surveillance of workers exposed to carbon disulfide should include the FM 100-Hue Test as a sensitive and easy method.