Design and Preparation of Magnetism-Driven Intelligent Hydrogel Actuators

Novel kinds of magnetism-driven poly N,N-dimethylacrylamide bilayer intelligent hydrogels with various nanofibrillated cellulose (NFC) contents were prepared successfully via one-step insitu free radical polymerization. The bilayer hydrogels possessed high mechanical strength, efficient swelling and steady magnetic response. With the increase of nanofibrillated cellulose content, the crosslinking density of the hydrogels increased, leading to the decrease of swelling rate and increase of mechanical strength and swelling bending degree of hydrogel actuators, respectively. Fe3O4 particles existed tightly on the micropore surfaces of the hydrogels, which built the function base of magnetic response of hydrogel actuators. The addition of Fe3O4 was irrelevant to the variation of crosslinking density. The bilayer structure exhibited high bonding strength. Based on intelligent responsive properties, bilayer hydrogels were designed as soft magnetism-driven actuators, realizing capture and transportation properties and provided material candidates for soft robots.

[Preliminary application of postoperative fast track transfer to intensive care unit for the geriatric hip fractures under enhanced recovery after surgery]

Objective: To develop a fast track transfer to intensive care unit (ICU) for the perioperative high-risk elderly patients after hip fracture surgery and analyze the preliminary clinical effect of the application. Methods: From January 2014 to December 2017, before the application of postoperative fast track transfer to ICU, the clinical data of 195 elderly patients with hip fracture were included in a retrospective analysis. Among 195 hip fracture patients, 18 were transferred to ICU post operation (non-fast track group). Multivariate logistic regression analysis was applied to investigate relevant risk factors for transferring to ICU after hip fracture surgery. Based on risk factors acquired from the analysis and clinical experience, the fast track transfer to ICU for the perioperative high-risk elderly patients after hip fracture surgery was constructed according to the preliminary and experiential criteria. From January 2018 to December 2019, the clinical data of 70 patients (fast track group) who were transferred to ICU after hip fracture surgery through the fast track were collected and compared with non-fast track group. Results: Multivariate regression analysis revealed that American Society of Anesthesiologists classification(≥Ⅲ) (OR=4.260, 95%CI:1.157-15.683, P=0.029), pre-hospital stage (≥48 h) (OR=4.301, 95%CI:1.212-15.266, P=0.024), hemoglobin concentration at admission(<90 g/L) (OR=7.979, 95%CI:1.936-32.889, P=0.004), coronary heart disease as one comorbidity(OR=6.063, 95%CI:1.695-21.693, P=0.006) were independent risk factors for transferring to ICU after hip fracture surgery. There were no significant difference in gender, age, fracture type, hemoglobin concentration at admission and time of pre-hospital stage between the non-fast track group and fast track group(all P>0.05). However, the number of comorbidities in the fast track group was significantly higher than that in the non-fast track group (Z=-1.995, P=0.046). The time to surgery, postoperative hospital stay, and length of hospital stay in fast track group were all significantly less than those in non-fast track group (Z=-2.121, -2.726, -3.130, all P<0.05). Also, there were fewer medical consultations needed and fewer patients who stayed in ICU more than or equal to 2 nights in fast track group than that in non-fast track group(all P<0.05). There were no significant difference in the rate of patients who transferred from the general ward to ICU after transferring from ICU to the general ward, the proportion of patients who received more than or equal to 4 departments, operation time, hospitalization expense, mortality during hospitalization, 30-day mortality and 90-day mortality after operation between the two groups(all P>0.05). Conclusions: The fast track constructed in this study can reduce time to surgery, postoperative hospitalization stay and length of hospitalization stay for the perioperative high-risk elderly patients with hip fractures and is a specific clinical application of eras concept based on multidisciplinary team.

[The Role of Soluble HLA-G in the Vertical Transmission of Toxoplasma gondii]

Soluble human leukocyte antigen G (sHLA-G) plays a key role in pregnancy through interaction with decidual natural killer (dNK) cell inhibitory receptors at the maternal-fetal interface. To demonstrate the possible role of sHLA-G during the pregnancy with Toxoplasma gondii infection, we compared the concentration of a murine functional homolog of sHLA-G, Qa-2, in T. gondii infected and non-infected pregnant C57BL/6 mice, and that of sHLA-G in BeWo culture supernatant. In addition, the levels of KIR2DL4 expressed on human dNK cells and NKG2A in pregnant mice were evaluated. We showed that T. gondii infection result in significant increase in the level of Qa-2 and NKG2A in pregnant mice. sHLA-G and KIR2DL4 in human samples were also significantly upregulated under the condition of T. gondii infection. The further treatment with sHLA-G antibody could reduce the expression level of KIR2DL4 which was upregulated by T. gondii infection. In summary, sHLA-G could upregulate the expression level of KIR2DL4 which lead to excessive immunological tolerance, and further contributed to T. gondii immunity escaping and affecting fetus via vertical transmission which may lead to adverse outcomes.

Fatigue device driven by a three degree of freedom tripodal piezoelectric actuator

A miniature piezoelectric-driven fatigue device with three degrees of freedom is developed. The device integrates two fatigue testing functions, including uniaxial tensile fatigue and tensile-bending combined loading modes. The synchronous tensile-bending loading principle is described, which is applicable for calculating the vector displacements along two orthogonal directions and investigating the anisotropic fatigue properties. Regarding the combined loading mode, maximum load/displacement amplitudes for tensile and bending vector components that could be achieved are 16.9 N/22.8 µm and 3.3 N/5.6 µm, respectively. Based on tensile and tensile-bending combined fatigue loading modes, the displacement responses and fatigue lives at loading frequencies ranging from 1 Hz to 100 Hz are valuated experimentally to indicate the validation.

Effect of dietary conjugated linoleic acid supplementation during late gestation on colostrum yield, fatty acid composition, and IgG concentrations in primiparous sows

This experiment was conducted to evaluate the effects of dietary conjugated linoleic acid (CLA) supplementation during late gestation on reproductive performance, colostrum yield, colostral fatty acid composition, and immunoglobulin G (IgG) concentrations in primiparous sows. Twenty-four primiparous Landrace × Large White pregnant sows were randomly selected and assigned to four dietary treatments: 0% (control), 0.75%, 1.50%, and 2.25% CLA supplementation from day 85 of gestation to parturition. During lactation, all sows were fed the same commercial diet. The preweaning mortality of suckling piglets born to dams fed supplemental CLA did decrease linearly (P = 0.01) during lactation. Administration of CLA during gestation increased linearly (P < 0.01) total saturated fatty acids and decreased linearly (P < 0.01) monounsaturated fatty acids and polyunsaturated fatty acids in colostrum. The concentrations of CLA isomers were higher (P < 0.01) in colostrum from primiparous sows fed CLA diets than in the control group. Feeding CLA increased (P < 0.05) colostral IgG concentrations, as well as that in the serum of neonatal piglets. In conclusion, 2.25% CLA supplementation in the diet of primiparous sows during late gestation could improve the passive immunity through colostral IgG and the survival of suckling piglets.

[Correlation between the parameters of acoustic cardiography and BNP, LVEF and cardiac function grading in patients with chronic heart failure]

Objective: To explore the correlation between the parameters of the new generation of Acoustic Cardiography and brain natriuretic peptide (BNP), left ventricular ejection fraction (LVEF) and cardiac function grading in the diagnosis of heart failure. Methods: One hundred and sixty-eight inpatients, who were hospitalized in Department of Cardiology, Haikou People's Hospital from May 2016 to July 2017, were enrolled as heart failure group, including NYHA class Ⅰ(n=29), NYHA class Ⅱ(n=40), NYHA class Ⅲ(n=64), NYHA class Ⅳ (n=35). And eighty-seven patients with normal cardiac function were selected as healthy control group. The data of the two groups were analyzed after the Acoustic Cardiography test, BNP determination and LVEF examination. Results: The differences in QRS duration, electromechanical activation time (EMAT), EMAT%, systolic dysfunction index (SDI), third heart sound (S3) and other indicators among the groups with different levels of cardiac function were statistically significant (P<0.05). The difference in left ventricular systolic time (LVST) between the cardiac function grade Ⅰ and healthy group was not significant (P>0.05), while the differences among the rest groups were significant. There was a positive correlation between QRS duration, EMAT%, SDI, S3 and BNP (t=9.46, 11.38, 12.14, 9.67, respectively, P<0.05); LVST and BNP were negatively correlated (t=-14.27, P<0.05). There was a negative correlation between QRS duration, EMAT%, SDI, S3 and LVEF (t=11.24, -8.764, -2.393, -0.579, respectively, P<0.05). There was a positive correlation between LVST and LVEF (t=23.48, P<0.05). There was a positive correlation between QRS duration, EMAT%, SDI, S3 and cardiac function grading (β=0.003, 0.234, 0.419, 0.352, respectively, P<0.05). There was a negative correlation between LVST and cardiac function grade (β=-0.021, P<0.05). Conclusion: The parameters of the Acoustic Cardiography test (EMAT%, EMAT, SDI, S3 ) are closely related to BNP, LVEF and cardiac function grading, and can be used as assistant indexes for the diagnosis and evaluation of heart failure.

Note: Motor-piezoelectricity coupling driven high temperature fatigue device

The design and performance evaluation of a novel high temperature fatigue device simultaneously driven by servo motor and piezoelectric actuator is our focus. The device integrates monotonic and cyclic loading functions with a maximum tensile load of 1800 N, driving frequency of 50 Hz, alternating load of 95 N, and maximum service temperature of 1200 °C. Multimodal fatigue tests with arbitrary combinations of static and dynamic loads are achieved. At temperatures that range from RT to 1100 °C, the tensile and tensile-fatigue coupling mechanical behaviors of UM Co50 alloys are investigated to verify the feasibility of the device.

[Incidence and risk factors of delirium in patients post permanent pacemaker implantation]

OBJECTIVE

To evaluate the incidence and risk factors of postoperative delirium in patients post permanent pacemaker implantation.

METHODS

Patients underwent permanent pacemaker implantation in our department from September 2013 to February 2015 were included in this study. Delirium was measured by the confusion assessment method on the first three postoperative days. All the patients were divided into the postoperative delirium group and the non-delirium control group according to whether new onset delirium was diagnosed. Risk factors significantly associated with postoperative delirium detected by univariate analysis were entered into multivariable analysis to define the independent predictors of postoperative delirium.

RESULTS

A total of 225 patients were enrolled in this study. The incidence of postoperative delirium was 5.3%. Patients developing postoperative delirium were older ((83±5) years vs. (74±11) years, P=0.002), had a significantly higher incidence of blood pressure fluctuations (58.3% (7/12) vs. 4.7% (10/213), P<0.001), hyponatremia (25.0% (3/12) vs. 5.2% (11/213), P=0.030) and had higher systolic blood pressure ((157±35) mmHg vs. (136±22)mmHg, 1 mmHg=0.133 kPa, P=0.007). However, patients developing postoperative delirium had lower preoperative average heart rate ( (47±18)bpm vs. (58±15)bpm, P=0.007). Multiple regression analysis showed that advanced age (OR= 2.984, 95% CI: 1.226-7.624, P=0.016) and blood pressure fluctuations (OR=27.393, 95% CI: 6.735-111.417, P<0.001) are the independent risk factors for pacemaker patients with postoperative delirium.

CONCLUSION

Advanced age and blood pressure fluctuations are independent risk factors of postoperative delirium in patients post permanent pacemaker implantation.

Developing a computer-controlled simulated digestion system to predict the concentration of metabolizable energy of feedstuffs for rooster

Four experiments were conducted to evaluate the effectiveness of a computer-controlled simulated digestion system (CCSDS) for predicting apparent metabolizable energy (AME) and true metabolizable energy (TME) using in vitro digestible energy (IVDE) content of feeds for roosters. In Exp. 1, the repeatability of the IVDE assay was tested in corn, wheat, rapeseed meal, and cottonseed meal with 3 assays of each sample and each with 5 replicates of the same sample. In Exp. 2, the additivity of IVDE concentration in corn, soybean meal, and cottonseed meal was tested by comparing determined IVDE values of the complete diet with values predicted from measurements on individual ingredients. In Exp. 3, linear models to predict AME and TME based on IVDE were developed with 16 calibration samples. In Exp. 4, the accuracy of prediction models was tested by the differences between predicted and determined values for AME or TME of 6 ingredients and 4 diets. In Exp. 1, the mean CV of IVDE was 0.88% (range = 0.20 to 2.14%) for corn, wheat, rapeseed meal, and cottonseed meal. No difference in IVDE was observed between 3 assays of an ingredient, indicating that the IVDE assay is repeatable under these conditions. In Exp. 2, minimal differences (<21 kcal/kg) were observed between determined and calculated IVDE of 3 complete diets formulated with corn, soybean meal, and cottonseed meal, demonstrating that the IVDE values are additive in a complete diet. In Exp. 3, linear relationships between AME and IVDE and between TME and IVDE were observed in 16 calibration samples: AME = 1.062 × IVDE - 530 (R(2) = 0.97, residual standard deviation [RSD] = 146 kcal/kg, P < 0.001) and TME = 1.050 × IVDE - 16 (R(2) = 0.97, RSD = 148 kcal/kg, P < 0.001). Differences of less than 100 kcal/kg were observed between determined and predicted values in 10 and 9 of the 16 calibration samples for AME and TME, respectively. In Exp. 4, differences of less than 100 kcal/kg between determined and predicted values were observed in 3 and 4 of the 6 ingredient samples for AME and TME, respectively, and all 4 diets showed the differences of less than 25 kcal/kg between determined and predicted AME or TME. Our results indicate that the CCSDS is repeatable and additive. This system accurately predicted AME or TME on 17 of the 26 samples and may be a promising method to predict the energetic values of feed for poultry.

Effects of dietary protein source on the digestive enzyme activities and electrolyte composition in the small intestinal fluid of chickens

An experiment was conducted to investigate the effects of dietary protein source on the digestive enzymes and electrolyte composition of digesta fluid in the duodenum, jejunum, and ileum of chickens. A 2 × 3 factorial and completely randomized design that used 2 types of diets that differed only in their protein source [a corn-soybean meal-miscellaneous meal diet (CSMD) and a corn-miscellaneous meal diet (CMD)] and 3 types of cannulated roosters (duodenal, jejunal, and ileal cannulations) was adopted. The experiments included 5 replicates for each of the 6 treatments, and each replicate involved 3 cannulated chickens. The digesta samples were collected for 1 h every 4 h between 09:30 and 18:30 h on d 31, 33, and 35 of the experiment. The amylase, lipase, trypsin, and chymotrypsin activities and the electrolyte composition in the duodenal, jejunal, and ileal fluid were determined. In general, no significant differences between the 2 dietary groups were observed for the mean of duodenal, jejuna, and ileal amylase, trypsin, chymotrypsin, and lipase, respectively. However, the duodenal amylase activity was lower in the CMD group than the CSMD group (P < 0.05), which was probably related to the lower duodenal pH value that was observed in this group (P < 0.01). A higher jejunal Mg(2+) concentration was observed in chickens that were fed the CMD (P < 0.05), whereas the differences in the Na(+), K(+), Cl(-), and Ca(2+) concentrations in the small intestine were not significant between the 2 diets (P > 0.05). In conclusion, the digestive enzymes and electrolytes in the small intestinal fluid of chickens adapted to the protein source of the diet, and each segment of the small intestine displayed different modifications.

Using corn starch as basal diet to determine the true metabolizable energy of protein feedstuffs in Chinese Yellow chickens

Two experiments were conducted to investigate the feasibility of using corn starch as the basal diet to determine the ME of protein feedstuffs using the TME assay in Chinese Yellow chickens. In the first experiment, the TME of corn starch were determined by force-feeding 25 or 40 g of feed. To test the repeatability of the bioassay, the same experiment was repeated 4 times. In the second experiment, the TME of soybean meal and cottonseed meal was determined by considering corn starch as the basal diet, while corn was fed alone to the chickens. To test the accuracy of the TME assay for individual ingredients, the additivity was evaluated by determining the TME of 3 mixed diets: corn-soybean meal diet, corn-cottonseed meal diet, and corn-soybean meal-cottonseed meal diet. In experiment 1, the value of endogenous energy loss was 16.76 to 18.46 kcal/48 h, and no significant differences between the 4 assays were noted. The TME and energy metabolizability of the 25-g corn starch treatment (4.06 kcal/g and 98.06%) were higher than those of the 40-g treatment (3.79 kcal/g and 91.45%; P < 0.01); whereas the CV were less than that of the 40-g treatment, indicating that it is reasonable to use the TME value of the 25-g treatment in feed formulation. In experiment 2, the TME values for corn, soybean meal, and cottonseed meal were 4.02, 3.39, and 2.92 kcal/g, respectively. The observed and predicted TME values of the corn-soybean meal, corn-cottonseed meal, and corn-soybean meal-cottonseed meal diets were in high agreement with differences ranging from -0.02 to 0.01 kcal/g. None of the differences was significant, indicating an accurate measure of the TME of the individual ingredients. Thus, using corn starch as the basal diet to determine the TME of protein feedstuffs was validated.

Differential fibronectin expression in activated C6 glial cells treated with ethanol

The central nervous system is particularly susceptible to alcohol effects and toxicity. Glial cells constitute the most common cell type in the brain and play critical roles in normal brain function and during infection and injury. Astrocytes in particular seem to be important targets for alcohol neurotoxicity during both development and in adulthood. To gain more insight into alcohol-mediated effects on astrocytes at the molecular level, gene expression in rat C6 glial cells was studied in the presence or absence of ethanol. The differential display of mRNA technique was used to screen the expressed genes in ethanol-treated rat C6 cells before and after treatment with lipopolysaccharide (LPS) combined with phorbol-12-myristate-13-acetate (PMA), conditions that mimic an infectious inflammatory state and cause immunologic activation. The present data show that fibronectin appeared as a major gene whose expression is increased in C6 cells by LPS plus PMA stimulation and decreased by chronic ethanol exposure, both in mRNA and protein levels. Fibronectin is a dimeric glycoprotein found in the extracellular matrix of most tissues, in the blood, and on cell surfaces and is involved in many cellular processes. These results show that chronic exposure to ethanol is associated with changes in astrocyte properties during immunologic activation that reduce fibronectin expression. The discovery of astrocyte fibronectin expression as a potential regulated target for chronic alcohol abuse may be useful in understanding, preventing, and treating some brain disorders associated with alcohol abuse and alcoholism.

Lipopolysaccharide-induced expression of IP-10 mRNA in rat brain and in cultured rat astrocytes and microglia

Using mRNA differential display technique, we have found a differentially expressed band in rat brain, designated HAP2G1, which was the strongest one induced in response to peripheral administration of lipopolysaccharide (LPS). Sequence analysis showed that HAP2G1 cDNA is the rat homologue of the human alpha-chemokine IP-10. Using RT-PCR technique and in situ hybridization, we demonstrate that IP-10 mRNA was expressed only in brain tissue of rats treated with LPS and not in control brain tissue. Using semi-quantitative PCR, we found that both cultured astrocytes and microglia express IP-10 mRNA after treatment with LPS. LPS-induced IP-10 mRNA reached peak levels in rat brain and in cultured microglia at approximately 3 h after treatment with LPS. At 10 h, IP-10 mRNA was markedly decreased, and at 24 h it was low but still detectable by PCR or in situ hybridization. In contrast to unstimulated microglia, unstimulated astrocytes constitutively expressed IP-10 mRNA at a low level. Increased IP-10 expression could possibly be involved in the microglia response to inflammatory stimuli in vivo.

Mutations at codon 249 of p53 gene in human hepatocellular carcinomas from Tongan, China

Codon 249 (exon 7) of the putative tumor suppressor gene p53 is a mutational hot-spot for hepatocellular carcinoma (HCC) but not other tumors. DNA samples from primary HCC patients from Tongan, an area of high HCC incidence in China (> 40 per 100,000 population), were analyzed for specific mutations in codon 249 of the p53 gene using polymerase chain reaction (PCR)/restriction-digest methods and direct DNA sequencing. Seven of the 21 samples screened were found to have a point mutation at the third base position of codon 249 (AGG to AGT). The result is consistent with previous reports that the G-->T transversion is positively associated with the level of dietary aflatoxin B1 (AFB1) contamination, which has been implicated as one of the risk factors in Tongan area. Of the 7 HCC patients that contained the codon 249 point mutation, one was hepatitis B virus (HBV)-negative. This is only the second documentation of an HCC patient harboring the p53 codon 249 mutation, who was HBV-negative.

Identification by monoclonal antibodies of an antigen shed by human bladder cancer cells

The reactivities of two anti-bladder cancer monoclonal antibodies, AN43 and BB369, were characterized. AN43 and BB369 reacted with a majority (greater than 50%) of bladder cancer tissue sections tested by immunoperoxidase staining. When tested against a panel of 27 normal human tissues, AN43 and BB369 reacted only with urothelium and stomach. AN43 and BB369 showed identical binding patterns and competed for binding on bladder cancer cells, suggesting that the two antibodies react with identical or spatially close epitopes. Bound BB369 antibody was rapidly shed from the surface of viable UM-UC-9 human bladder cancer cells. The antigen was found in spent tissue culture medium from the UM-UC-9 human bladder cancer cell line. AN43 and BB369 define a shed bladder tumor-associated antigen with limited distribution on normal tissues. The antigen is different from bladder tumor-associated antigens defined by other monoclonal antibodies and may be useful for the diagnosis and follow-up of patients with bladder cancer.

Human renal carcinoma: characterization of five new cell lines

Five human renal carcinoma cell lines have been established in long-term tissue culture. Two of the cell lines, UM-RC-2 and UM-RC-3, produced clear cell tumors in athymic nude mice. The cell lines have been characterized by staining with oil red O, doubling time in vitro, and number of chromosomes. Although protein A assay reactivity of autologous combinations of patient's sera and tumor cells were seen with all five cell lines, similar binding was also found with autologous normal kidney cultures. However, the immune adherence assay demonstrated low titer autologous reactivity with two renal carcinoma cell lines but not with the corresponding normal kidney cultures. This strongly suggest host recognition of tumor-associated antigens. Characterization of cell surface antigens with murine monoclonal antibodies demonstrated shared reactivity between normal kidney tubular cells and renal carcinoma cells. Antibody A68.11 reacted strongly with all five cell lines. Antibody A80 bound to only UM-RC-3 and UM-RC-6.