Adsorption-Catalysis-Conversion of Polysulfides in Sandwiched Ultrathin Ni(OH)2 -PANI for Stable Lithium-Sulfur Batteries.

Strong adsorption and catalysis for lithium polysulfides (LiPSs) are critical toward the electrochemical stability of Li-S batteries. Herein, a hollow sandwiched nanoparticle is put forward to enhance the adsorption-catalysis-conversion dynamic of sulfur species. The outer ultrathin Ni(OH)2 nanosheets not only confine LiPSs via both physical encapsulation and chemical adsorption, but also promote redox kinetics and accelerate the conversion of sulfur species, which is revealed by experiments and theoretical calculations. Meanwhile, the inner hollow polyaniline soft core provides a strong chemical bonding to LiPSs after vulcanization, which can chemically adsorpt LiPSs, and synergistically confine the shuttle effect. Moreover, the Ni(OH)2 nanosheets with a large specific area can enhance the wettability of electrolyte, and the flexible hollow sandwiched structure can accommodate the volume expansion, promoting sulfur utilization and structural stability. The obtained cathode exhibits excellent electrochemical performance with an initial discharge capacity of 1173 mAh g-1 and a small capacity decay of 0.08% per cycle even after 500 cycles at 0.2 C, among the best results of Ni(OH)2 -based materials for Li-S batteries. It is believed that the combination of adsorption-catalysis-conversion will shed a light on the development of cathode materials for stable Li-S batteries.

Intranasal delivery of plasmids expressing bovine herpesvirus 1 gB/gC/gD proteins by polyethyleneimine magnetic beads activates long-term immune responses in mice.

BACKGROUND: DNA vaccine is one of the research hotspots in veterinary vaccine development. Several advantages, such as cost-effectiveness, ease of design and production, good biocompatibility of plasmid DNA, attractive biosafety, and DNA stability, are found in DNA vaccines. METHODS: In this study, the plasmids expressing bovine herpesvirus 1 (BoHV-1) gB, gC, and gD proteins were mixed at the same mass ratio and adsorbed polyethyleneimine (PEI) magnetic beads with a diameter of 50 nm. Further, the plasmid and PEI magnetic bead polymers were packaged into double carboxyl polyethylene glycol (PEG) 600 to use as a DNA vaccine. The prepared DNA vaccine was employed to vaccinate mice via the intranasal route. The immune responses were evaluated in mice after vaccination. RESULTS: The expression of viral proteins could be largely detected in the lung and rarely in the spleen of mice subjected to a vaccination. The examination of biochemical indicators, anal temperature, and histology indicated that the DNA vaccine was safe in vivo. However, short-time toxicity was observed. The total antibody detected with ELISA in vaccinated mice showed a higher level than PBS, DNA, PEI + DNA, and PBS groups. The antibody level was significantly elevated at the 15th week and started to decrease since the 17th week. The neutralizing antibody titer was significantly higher in DNA vaccine than naked DNA vaccinated animals. The total IgA level was much greater in the DNA vaccine group compared to other component vaccinated groups. The examination of cellular cytokines and the percentage of CD4/CD8 indicated that the prepared DNA vaccine induced a strong cellular immunity. CONCLUSION: The mixed application of plasmids expressing BoHV-1 gB/gC/gD proteins by nano-carrier through intranasal route could effectively activate long-term humoral, cellular, and mucosal immune responses at high levels in mice. These data indicate PEI magnetic beads combining with PEG600 are an efficient vector for plasmid DNA to deliver intranasally as a DNA vaccine candidate.

Dispersive Liquid-Liquid Microextraction Combined with Microwave Demulsification for Determination of FAME Residuals in Biodiesel Wastewater.

Biodiesel consists of various fatty acid methyl esters (FAMEs) that are mainly produced through transesterification of plant oil or animal fat. It is essential for biodiesel to be purified utmostly to meet its product standard before being traded, while the universal purification method has been water washing. However, water washing inevitably causes the residual of FAMEs in wastewater, which represents a loss of industrial profits. For the purpose of determination and monitoring of the FAME profile in wastewater, there is a necessity to develop a fast and reliable approach with small volume of sample in need. Hence, in this study, a combination of dispersive liquid-liquid microextraction (DLLME) and microwave demulsification is applied for the enrichment of residual FAMEs in water, followed by qualitative and quantitative analyses using gas chromatography-mass spectrometry. The results indicate that the optimal extractant in DLLME approach is toluene. And the optimal parameters are 20 mL of water sample, 80 µL of toluene as the extractant, 60 s of ultrasonic irradiation duration, 200 W of microwave power and 2 min of microwave irradiation duration. The standard curves and linear equations obtained with these conditions are used for the quantitative analysis of biodiesel wastewater, which reveals that there was 50.35 mg·L-1 of the total FAME residuals in wastewater. To the best of our knowledge, it is for the first time that the combined technique of DLLME and microwave demulsification is applied in determination of residual FAMEs in water samples. The proposed method corresponds to small volumes of sample and extractant and short analytical period. It also has the potential to be extended to the analysis of other water pollutants.

Microwave-assisted-demulsification dispersive liquid-liquid microextraction for the determination of triazole fungicides in water by gas chromatography with mass spectrometry.

A novel microwave-assisted-demulsification dispersive liquid-liquid microextraction technique was established for determination of three triazole fungicides in environmental water samples by gas chromatography with mass spectrometry. Importantly, microwave irradiation has been applied in demulsification to achieve the phase separation and enrichment of triazole fungicides in water samples successfully with low-density toluene as extractant. The experimental variables, including microwave power, microwave time, ultrasonic time, type and volume of extraction solvent, and effect of salting out were investigated. Under the optimized conditions, the method showed good linearity for myclobutanil, tebuconazole, and difenoconazole in the range of 1-100 µg/L. The limits of detection and the limits of quantification were within the range of 0.14-0.27 and 0.47-0.90 µg/L, respectively. The suitable enrichment factors for three triazole pesticides were in the range of 425-636. The recoveries were between 89.3 and 108.7%, and the relative standard deviations were from 5.4 to 8.6%. Finally, environmental water samples were used to verify the applicability of the proposed method for analysis of triazole fungicides targets. It can be concluded that the developed microwave-assisted-demulsification dispersive liquid-liquid microextraction gas chromatography with mass spectrometry method was a rapid, efficient, reliable, and environmental friendly way for analysis of triazole fungicides in water.

Microwave-Assisted Simplified Simultaneous Distillation Coupled with Ionic Liquid Pretreatment for the Analysis of Essential Oil in Schisandra sphenanthera.

Simultaneous distillation extraction (SDE) is quite useful for the separation of volatile compounds from an analyte when their contents are quite low. In this study, a simplified SDE approach is applied for the extraction of essential oil from Schisandra sphenanthera, with microwave as heating source, [Bmim][Cl] as the medium for pretreatment, and gas chromatography-mass spectrometry as the analytical approach. Consequently, the improvement resulted from [Bmim][Cl] pretreatment is demonstrated by taking comparison with blank experiments. Totally 61 compounds have been detected in the essential oil obtained by using [Bmim][Cl] pretreatment, while without [Bmim][Cl] pretreatment, only 53 compounds can be detected. Moreover, [Bmim][Cl] pretreatment can also resulted in a higher yield of essential oil. The experimental results demonstrate that the simplified SDE coupled with ionic liquid pretreatment is a feasible approach for the extraction of essential oil from S. sphenanthera with high efficiency as 0.85% of essential oil yield has been obtained, and can be potentially extended to the extraction of essential oil or other target volatile compounds with low content.

Transesterification of soybean oil by using the synergistic microwave-ultrasonic irradiation.

Microwave and ultrasound have been demonstrated to be outstanding process intensification techniques for transesterification of oil. According to their mechanisms, simultaneous effects can surely bring about better enhancement than sole microwave or ultrasound. Therefore, this study aimed to investigate the important factors and their suitable levels in the KOH-catalyzed transesterification of soybean oil with methanol by using synergistic assistance of microwave-ultrasound (CAMU). The feasibility of application of CAMU in transesterification of oil was demonstrated. When the dosage of methanol, soybean oil and KOH were 15.4g, 34.7g (with methanol-to-oil molar ratio of 12:1) and 1g, respectively, and the microwave power, ultrasonic power, ultrasonic mode, reaction temperature and reaction time were 700W, 800W, 1:0, 65°C and 6min, respectively, the transesterification reached 98.0% of yield, being the highest yield among all the results obtained; while by using 600W of microwave plus stirring instead of CAMU, only 57.4% of yield could be obtained. Compared with other reaction techniques, the transesterification by applying novel CAMU was found to have remarkable advantages. Furthermore, by monitoring the variation of real-time temperature and microwave power during transesterification reactions with different microwave operation time and by taking comparison of the corresponding yield, it was demonstrated that the main reason for the acceleration of microwave-assisted transesterification was the polarization and further activation of reactants caused by microwave irradiation, but not the factor of fast heating.

Heat shock protein 90 mediates anti-apoptotic effect of diazoxide by preventing the cleavage of Bid in hypothermic preservation rat hearts.

BACKGROUND: Successful organ preservation is the premise for clinical organ transplantation. The present study investigated whether heat shock protein 90 (Hsp90) is important in the anti-apoptotic effect of diazoxide in hypothermic preservation rat hearts. METHODS: Isolated rat hearts were preserved in Celsior solution, with or without diazoxide, for 3 to 9 hours, followed by 60 minutes of reperfusion. Cell apoptosis was assessed by terminal deoxynucleotide transferase-mediated deoxy uridine triphosphate nick-end labeling. The left ventricular developed pressure (LVDP) was recorded. Expression of Hsp90 protein and cleavage of Bid were detected by Western blot and polymerase chain reaction. RESULTS: After hypothermic preservation for 3 to 9 hours, the LVDP recovery rate significantly decreased and cardiomyocyte apoptosis index increased in a time-dependent manner. When compared with the 9-hour preservation group, Celsior solution supplemented with diazoxide significantly enhanced the LVDP recovery rate and decreased the apoptosis index. The cleavage of Bid increased after 9 hours of hypothermic preservation, which was inhibited by Celsior solution supplemented with diazoxide. Hypothermic preservation of rat hearts for 9 hours decreased the expression of Hsp90, whereas diazoxide supplementation significantly increased the expression of Hsp90. The Hsp90 inhibitor 17-allylamino-17-demethoxy-geldanamycin inhibited the diazoxide-induced decrease in cleavage of Bid, improvement of cardiac function, and decrease of apoptosis. Hsp90 inhibitor had no effect on the diazoxide-induced increase of total Cx43 protein expression in hearts preserved 9 hours, but inhibited the diazoxide-induced increase of mitochondrial Cx43 protein level. CONCLUSION: Hsp90 might mediate diazoxide-induced cardioprotection against apoptosis in hypothermic preservation heart by preventing the cleavage of Bid.

[Effects of angiotensin converting enzyme inhibitor on the expression of angiotensin converting enzyme 2 in atrium of patients with atrial fibrillation].

OBJECTIVE: To investigate the expression of angiotensin converting enzyme 2 (ACE2) and the changes treated with angiotensin converting enzyme inhibitor (ACEI), and its signal transduction pathway. METHODS: Atrial tissues were obtained from 47 patients with RHD undergoing cardiac surgery. The mRNA of ACE2 and ACE were semi-qualified by RT-PCR and normalized to the gene beta-actin. Western blot analysis was employed to examine the expressions of ACE2, ACE, ERK1/2 and phosphorylated ERK (pERK1/2). The atrial tissue angiotensin II (Ang II) content was determined by radioimmunoassay detection. RESULTS: The expression of ACE2 was significantly decreased (P < 0.05), the expression of ACE and pERK1/2 were significantly increased (P < 0.05), and the level of atrial tissue Ang II was significantly increased in patients with chronic atrial fibrillation group (CAF) compared with sinus rhythm group (SR) (P < 0.05). Compared with CAF patients treated without ACEI, the expression of ACE2 significantly increased (P < 0.01), and the relative activity of ERK1/2 significantly decreased (P < 0.05), whereas the expression of ACE and the level of atrial tissue Ang II remained unchanged in CAF patients treated with ACEI. CONCLUSIONS: The study suggested that the dysequilibrium of ACE/ACE2 might play an important role in the process of atrial fibrillation, which may be related to the activation of ERK1/2 pathway. The clinical effect of long-term treatment of ACEI maybe associated with elevated ACE2 expression but not ACE expression.

[Study on a grey model for evaluation of Anopheles minimus density].

OBJECTIVE: To establish Anopheles minimus density evaluation model based on climate, environmental and remote sensing data. METHODS: 27 townships in 10 counties of Yunnan Province were chosen as field spots. Data on climate, environment, remote sensing and An. minimus density were collected from 1984 to 1993. Grey correlation analysis was carried out to study the relationship of 18 indices with An. minimus density. E variable was developed and its relation to the An. minimus density was analyzed to establish an evaluation model. RESULTS: Eight indices were selected based on a grey threshold 0.70: Dry season average temperature > dry season temperature(min) > wet season temperature(min) > wet season NDVI > wet season average temperature > the ratio of paddy field in total arable land > dry season temperature(max) > wet sea son temperature(max). The An. minimus density evaluation model was derived as follows: [formula: see text] The correct rate of evaluation by the model was 92.0%. e0.5 = 18%, with an average relative error of 21%. CONCLUSION: A quasi-evaluation on the An. minimus density can be made by applying the grey model.

Secondary rupture of aorta following the surgical management of aortoesophageal fistula.

A patient suffering from an aortoesophageal fistula (AEF) caused by a fish bone, was treated in our institute in 2000. The operation was successful and the patient had an uneventful early postoperative course. However, the patient died of frank hematemesis on the 6th postoperative day due to secondary rupture of the aorta. The lessons learnt and surgical efforts to manage AEF caused by an esophageal foreign body are discussed.

[The application of remote sensing data in epidemic situation analysis of malaria and encephalitis B].

OBJECTIVE: To explore the epidemic regularity of malaria and encephalitis B by using the data of remote sensing (Rs) in flood area. METHODS: The demarcation standards in counties with flood disaster were formed depending on the descriptive analysis results of remote sensing data and combined with that of field survey. Three indicators were used to analyze the epidemic situation of malaria and encephalitis B in Jiangxi Province during a heavy flooding in 1998: the increasing percentage of incidence in 1998 comparing with the median of past five years (1993-1997), the increasing percentage of incidence in 1998 comparing with that of 1997, the increasing percentage of incidence in 1999 comparing with that of 1998. RESULTS: The demarcation standards of flooding counties were defined as follows: by Rs, a county with a flood area of over 100 thousand mu was classified into group one, a county with a flood area under 100 thousand mu was classified into group two, a county with reported flood but not identified by RS was classified into group three, the other counties in the province were classified into group four. The malaria incidence in the province in 1998 was at an average historical level. Compared with 1997, malaria incidence in each group increased in 1998 by 111.61% in group one, 97.50% in group two, 43.63% in group three. So there is an evident correlation between the flood area by Rs and the increasing of malaria incidence (Rs = 0.893, P < 0.05). Malaria incidence in 1999 in non-flood area increased by 83.39% in comparison with that of 1998. The encephalitis B incidence increased by 252.03% in 1998 in group four compared with that of 1997; while the incidence increased in all the four groups in 1999 than that of in 1998. CONCLUSION: The remote sensing data on flood can help fully analyze the epidemic situation of malaria and encephalitis B.

[Expression of connexin in atrium of patients with atrial fibrillation and its signal transduction pathway].

OBJECTIVE: To explore the expression of connexin (Cx) and its signal transduction pathway in the atrium of patients with atrial fibrillation (AF). METHODS: Atrial tissue samples of 63 patients undergoing cardiac surgery, including patients with chronic AF or paroxysmal AF (PAF), and those with sinus rhythm, were collected during operation. The mRNA expressions of calcineurin B and mitogen-activated protein kinase-1 (MKP-1) were detected by semi-quantitative RT-PCR. The protein expressions of extracellular-signal regulated kinase 1 (ERK1), phospho-ERK1 (P-ERK1), Cx40 and Cx43 were analyzed by Western blotting. HE staining and immunohistochemistry were used to examine the distribution of Cx40 and Cx 43. RESULTS: Increased amounts of Cx40 protein (left atrium: 2.2 +/- 0.8, 2.2 +/- 0.6; right appendages: 2.1 +/- 0.5, 2.0 +/- 0.8) were found in the left atrium and right appendages of patients with Chronic persistent AF (CAF) or paroxysmal AF (PAF) (P < 0.05). The expression of Cx43 was only increased in the left atrium of patients with CAF and PAF (3.1 +/- 0.6, 2.8 +/- 0.7 vs 1.0 +/- 0.2, both P < 0.05). The amounts of Calcineurin B mRNA, MKP-1 mRNA and P-ERK1 of patients with CAF or PAF were significantly increased compared with patients in sinus rhythm (P < 0.05). Immunohistochemistry revealed that Cx40 and Cx43 of CAF patients and PAF patients acculmated in the intracellular site, and at the lateral member of atrial cells, both connexins redistributed. CONCLUSION: The increased expression and disorderly distribution of Cx 40 and Cx 43 protein in the atrium of AF patients may be related with the abnormal activation and disequilibria of regulation of ERK1, MKP-1 and calcineurin.

[Value of serum-vascular endothelial growth factor in the differential diagnosis of solitary pulmonary nodule].

OBJECTIVE: To evaluate serum-vascular endothelial growth factor (S-VEGF) in the differentiation of solitary pulmonary nodule (SPN). METHODS: Serum level of VEGF of 68 patients with SPN was measured by ELISA kit, and compared with the control group of 20 normal subjects. The nodules were diagnosed by operation and pathology. RESULTS: The median level of S-VEGF was 42.5 (range from 10 to 170) pg/ml in the control, 44 (range from 18 to 360) pg/ml in benign nodule group and 75 (range from 18 to 890) pg/ml in lung cancer group, with significant difference observed between the nodule group and control (P < 0.01), and between the lung cancer group and the benign nodule group (P < 0.05), but not between the benign nodule group and the control. In addition, when S-VEGF in different pathologic types of the limited number of lung cancer patients were compared, no significant difference was observed. CONCLUSION: S-VEGF is valuable in the differential diagnosis of solitary pulmonary nodule. An elevated S-VEGF level >or= 100 pg/ml in patients with SPN may strongly speak for a malignant nodule. Operation is suggested.