Biosynthesis and Immunological Evaluation of a Dual-Antigen Nanoconjugate Vaccine Against Brucella melitensis

Brucellosis,caused by Brucella,is one of the most common zoonosis.However,there is still no vaccine for human use.Although some live attenuated vaccines have been approved for animals,the protection effect is not ideal.In this study,we developed a dual-antigen nanoconjugate vaccine containing both polysaccharide and protein antigens against Brucella.First,the antigenic polysaccharide was covalently coupled to the outer membrane protein Omp19 using protein glycan coupling technology,and then it was successfully loaded on a nano-carrier through the SpyTag/SpyCatcher system.After confirming the efficient immune activation and safety performance of the dual-antigen nanoconjugate vaccine,the potent serum antibody response against the two antigens and remarkable protective effect in non-lethal and lethal Brucella infection models were further demonstrated through different routes of administration.These results indicated that the dual-antigen nanoconjugate vaccine enhanced both T helper 1 cell(Th1)and Th2 immune responses and protected mice from Brucella infection.Furthermore,we found that this protective effect was maintained for at least 18 weeks.To our knowledge,this is the first Brucella vaccine bearing diverse antigens,including a protein and polysaccharide,on a single nanoparticle.Thus,we also present an attractive technology for co-delivery of different types of antigens using a strategy applicable to other vaccines against infectious diseases.

Effects of fruit thinning on ascorbate–glutathione cycle metabolism in black currants(Ribes nigrum L.)

To elucidate mechanisms regulating ascorbic acid (AsA) biosynthesis and accumulation in the fruit and leaves of black currants, AsA and the activities of key enzymes in the ascorbate-glutathione (AsA-GSH) cycle were measured from fruit set to fruit ripening during fruit thinning treatments of three common commercial black currant cultivars that differed in their AsA levels: 'Risager' (low), 'Brodtrop' (medium) and 'Adelinia' (high). Treatments were 50% fruit reduction (50% of total fruit set) by hand, control was no thinning. Fruit thinning treatment significantly increased AsA content in fruit of all three cultivars from weeks 2 to 8, significantly decreased AsA content in leaves from weeks 3 to 8. Dehydroascorbate reductase and monodehydroascorbate reductase activities in fruit and leaves had a similar pattern, increasing during week 2, rose until they peaked in week 4. Ascorbate peroxidase activity in fruit in the thinning treatment was slightly lower than in the control. Fruit thinning was shown to be a good model to test AsA biosynthesis regulation and accumulation in black currants. The results from our study provided strong evidence that AsA-GSH cycle involved in AsA synthesis and accumulation in fruit.

Effects of increased human tumor necrosis factor-like molecule 1A expression in peripheral blood of children with acute Guillain-Barre syndrome on interferon-gamma secretion

BACKGROUND： Human tumor necrosis factor-like molecule 1A （hTL1A） is a strong T helper cell type 1 （Thl） co-stimulator. Guillain-Barre syndrome （GBS） is an autoimmune disorder of the nervous system, which is mediated by Thl cells. OBJECTIVE： To determine hTL1A expression in peripheral blood T lymphocytes of acute GBS children and the effects of hTL1A on secretion of interferon-γ. DESIGN, TIME AND SETTING： A randomized, controlled, neuroimmunological in vitro study was performed at the Central Laboratory of First Hospital of Jilin University, China from November 2005 to November 2007. MATERIALS： Venous blood samples were obtained from 6 healthy donors, aged 6-12 years （all routine blood examination items were normal）, and 6 additional children with acute GBS, aged 6-12 years. The GBS children fell ill within 1 week and were not treated with hormones or immunoglobulin Purified recombinant human soluble tumor necrosis factor-like molecule 1A （rhsTL1A, 1 mg/mL, relative molecular mass 22 000, 6× His tag, soluble form） was supplied by the Central Laboratory of First Hospital of Jilin University, China. METHODS： Peripheral blood mononuclear cells were isolated from healthy donors using the standard Ficoll gradient centrifugation and were incubated in 96-well culture plates. The cells were assigned to the following groups： control （2 μg/mL phytohemagglutinin）, 2μg/mL phytohemagglutinin ＋ 25, 100 and 400 ng/mL rhsTL1A. T cell proliferation was quantified using the tritiated thymidine （3H-TdR） method. Serum interferon-γ levels in acute GBS children were detected by enzyme-linked immunosorbent assay （ELISA）. The ratio of hTL1A-positive T cells to CD3-positive T cells in peripheral blood of acute GBS children was determined using flow cytometry. Following in vitro pre-activation of peripheral blood mononuclear cells by 2 μg/mL phytohemagglutinin, the peripheral blood mononuclear cells were treated with 400 ng/mL exogenous rhsTLIA. Finally, peripheral blood mononuclear cell-secreted interferon-γlevels were measured by ELISA. MAIN OUTCOME MEASURES： The following parameters were measured： rhsTLIA stimulation index to stimulate proliferation of T cells; the serum interferon-γ levels in acute GBS children; the ratio of hTL1A-positive cells to CD3-positive cells; the levels of interferon-γ secreted by peripheral blood mononuclear cells in acute GBS children, as well as rhsTL1A-stimulated interferon-γ levels. RESULTS： T cell proliferation assay revealed that the stimulation index in each rhsTL1A group was greater than the control group. The stimulation index of the 400 ng/mL rhsTL1A group was the greatest. Serum interferon-γ levels in acute GBS children were significantly greater than the control group （P 〈 0.05）. The ratio of hTLIA＋ CD3＋ T cells to CD3＋ T cells in acute GBS children was significantly greater than the control group （P 〈 0.01 ）. Phytohemagglutinin stimulated peripheral blood mononuclear cells to a greater extent than 400 ng/mL rhsTL1A in the acute GBS group, and the secreted interferon-γ levels were significantly increased （P 〈 0.05）. CONCLUSION： In T cells pre-activated with 2 μg/mL phytohemagglutinin, proliferation was effectively increased with 400 ng/mL rhsTL1A treatment. Expression of hTLIA was increased in activated T cells from peripheral blood of acute GBS children, followed by increased interferon-γ secretion. These mechanisms are considered to be part of the pathological process that induces the secretion of inflammatory cytokines in GBS syndrome.

Effects of acrous gramineus and its component, alpha-asarone, on apoptosis of hippocampal neurons after seizure in immature rats

BACKGROUND： α-asarone and acrous gramineus have been shown to play a necessary function in enhancing the reactivity and convulsant threshold to electric stimulation of immature rats. They have also been shown to effectively suppress epileptic seizures induced by pentylenetetrazol in young rats. However, the mechanisms for these roles have been still unclear. OBJECTIVE： To observe the effects in immature rats of acrous gramineus and α -asarone on apoptosis of hippocampal neurons after epileptic seizure at the protein level, and to analyze the mechanism for these effects. DESIGN： A randomized controlled animal experiment. SETTINGS： Department of Pediatrics, First Hospital of Jilin University; Department of Histology and Embryology, Norman Bethune Medical School of Jilin University; Department of Internal Medicine, Children＇s Hospital of Changchun City; Department of Neurology, First Clinical Hospital affiliated to Harbin Medical University. MATERIALS： Fifty 3-week old Wistar rats, 34-40 g, irrespective of gender, were provided by Gaoxin Research Center of Medical Animal Experiment, Changchun. The animals were treated according to the animal ethical standards. The following chemicals were used for this study： acrous gramineus powders or infusion （Batch No, 0307113, Tianjiang Medicine Company Limited, Jiangyin）, α-asarone tablets （Batch No. 030219, Tianwei Pharmaceutical Factory, Shenyang）, and phenobarbital sodium tablets （Batch No. 020608, Xinya Medicine Company Limited, Shanghai）. The animals were divided into five groups randomly. First, ten rats were chosen as the normal controls. The remaining rats were treated with i.p. injections of pentylenetetrazol to stimulate an epileptic model. METHODS： The experiments were performed at the Neurological Laboratory of the First Hospital of Jilin University between October and December 2004. The rats were treated with i.p. injections of pentylenetetrazol （60 mg/kg） to establish an epileptic model. According to Racine＇ s standard, animals that reached stage 4 and 5 were chosen and randomly divided into 4 groups： model group, phenobarbital sodium, acrous gramineus, and a-asarone group. The normal control group was treated with an i.p. injection of physiological saline （0.5 mL）. After modeling, the model groups were intragastrically administrated 0.5 mL saline. The phenobarbital sodium, acrous gramineus, and α-asarone groups were intragastrically administrated 18 mg/kg/d phenobarbital sodium, 2 350 mg/kg/d acrous gramineus and 29 mg/kg/d α-asarone, respectively. The course of treatment was twice a day for 7 days. The normal group received intragastric administration of 0.5 mL saline at the same time. The rats were sacrificed and brain sections were prepared for light microscopy and electron microscopy. MAIN OUTCOME MEASURES： （1） Pathological changes of CA1 and CA3 hippocampal region neurons were observed by light microscopy and electronic microscopy. （2） Neuronal apoptosis in the CA1 and CA3 region was measured by TUNEL staining. （3） Bcl-2 and Bax expression in CA1 and CA3 region neurons was detected by immunohistochemistry and a ratio of Bcl-2/Bax was calculated. RESULTS： All 50 immature rats were included in the final analysis. （1） Pathological changes of CA1 and CA3 region hippocampal neurons： there were different pathological changes in all groups other than the normal control group. The number of damaged neurons in the model group was highest. The phenobarbital sodium, acrous gramineus, and α -asarone group exhibited different degrees of improvement. （2） Neuronal apoptosis in the CA1 and CA3 regions： there were less TUNEL-positive cells in the CA1 and CA3 regions in the normal control group. One week after PTZ-induced seizure, numerous TUNEL-positive cells were detected in the CA1 and CA3 regions in the remaining four groups. There was a significant difference between the normal control group and the remaining four groups （t = 12.089-19.162, P 〈 0.0 1）. The number of TUNEL-positive cells was less in the phenobarbital sodium, acrous gramineus, and α-asarone groups compared to the model group （t = 4.707-5.268, P 〈 0.01）. （3）Bcl-2 and Bax expression of neurons in the CA1 and CA3 regions： The number of Bcl-2- and Bax-positive cells was less in the normal control group. The Bax-positive cells exhibited a normal shape and had large round nuclei that were predominant. One week after PTZ-induced epilepsy, the number of Bcl-2- and Bax-positive cells in the CA1 and CA2 regions was significantly increased in the remaining four groups compared to the normal control group （t = 11.606-27.042, P 〈 0.01）. The Bax-positive cells exhibited a reduced size and nuclear pyknosis was predominant. However, there was no significant difference among the four groups （P 〉 0.05）. The number of Bcl-2-positive cells in the phenobarbital sodium, acrous gramineus, and a-asarone groups were significantly increased compared to the model group （t = 4.051-6.404, P 〈 0.01）. However, the number of Bax-positive cells was not significantly different among the four groups. The ratio of Bcl-2 to Bax expression was approximately 6.0 in the normal controls, 0.7 in the model group, and 1.0 in the remaining three groups. CONCLUSION： Acrous gramineus and a-asarone increased Bcl-2 expression and decreased Bax expression, and also reduced the number of apoptotic hippocampal neurons during PTZ-induced epileptic seizures in immature rats.

Effects of acrous gramimeus and its main component alpha-asarone on the reactivity and convulsive threshold of immature rats to electric stimulation

BACKGROUND： The traditional Chinese medicine acrous gramimeus is the dry rhizome of Acrous gramimeus Soland, a kind of Araceae familial perennial herb, which has a sedation action, anticonvulsant and antiepileptic effect. Its effective component has not been known yet, and α-asarone, the major component of the volatile oil extracted from acrous gramineus, has been supposed to play a necessary role in it. OBJECTIVE： To explore the effects of acrous gramimeu and α-asarone on the reactivity and convulsive threshold to electric stimulation in immature rats, furthermore, attempt to definitize the anticonvulsant effect of α-asarone. DESIGN： A randomized controlled study.SETTINGS： Department of Pediatrics, First Hospital of Jilin University; Department of Histology and Embryology, School of Basic Medical Sciences of Jilin University; Department of Neurology, First Clinical Hospital affiliated to Harbin Medical University; Department of Internal Medicine, Children＇s Hospital of Changchun City. MATERIALS ： Seventy 3-week immature Wistar rats （either males or females） of 34-40 g were used. Acrous gramimeu （1 g/bag, the content of α-oasarone was 0.046 26%-0.070 16%） with the batch number of 0307113 was provided by Tianjiang Medicine Company Limited, Jiangyin City. α-asarone tablet （60 mg per tablet） with the batch number of 030219 was provided by Tianwei Pharmaceutical Factory, Shenyang City. α-asarone injectable preparation （2 mL per piece） with the batch number of 030105 was provided by Shuanghe Medicine Limited Company, Beijing City. METHODS ： The experiments were carried out in the Neurological Laboratory of the First Hospital of Jilin University between August and October in 2004.① The 70 rats were randomly divided into intragastric subset and intraperitoneal subset. The intragastric subset included four groups of control, phenobarbital sodium, acrous gramimeu and α-asarone; the intraperitoneal subset included three groups of control, phenobarbital sodium and α-asarone. There were 10 rats per group. ② In the intragastric subset, different group was treated with saline （1 mL for each time, phenobarbital sodium （18 mg/kg per day）, acrous gramineu （2 350 mg/kg per day） and α-asarone （29 mg/kg per day） respectively twice every day for 5 days. In the intraperitoneal subset, different group was treated with saline （0.5 mL）, phenobarbital sodium （29 mg/kg） and α-asarone （2.9 mg/kg） respectively. ③ Before and after administration for 5 days in the intragastric subset as well as before and after administration for about 1 hour in the intraperitoneal subset respectively, the rats were given electric stimulation with the NIHOM KOMDEM multifunctional electrophysiological recorder, and the reactivity and convulsive threshold to electric stimulation of the rats were recorded. MAIN OUTCOME MEASURES： The reactivity and convulsive threshold to electric stimulation in immature rats were compared. RESULTS： All the rats were involved in the analysis of results. ① Results for intragastric administration： Before intragastric administration, there were no obvious differences in the reactivity and convulsive threshold to electric stimulation among the groups （P 〉 0.05）. After intragastric administration for 5 days, the reactivity and convulsive threshold to the electric stimulation had no obvious changes in the control group, but those were significantly higher than before administration in the drug administration groups （t=-3.317-7.401, P 〈 0.01）, which were also obviously higher than those in the control group （t=3.027-8.941, P 〈 0.01）, and those in the acrous gramimeu group and α-asarone group were not markedly different from those in the phenobarbital sodium group. ② Results for intraperitoneal injection： Before intraperitoneal injection, the reactivity and convulsive threshold to the electric stimulation had no obvious differences among the groups. After the intraperitoneal injection for 1 hour, the reactivity and convulsive threshold to the electric stimulation had no obvious change in the control group, but those were significantly higher than before administration in the drug administration groups （P 〈 0.01）, which were also obviously higher than those in the control group （t=6.211-7.237, P 〈 0.01; t=4.085-5.633, P 〈 0.05）, and there was no marked difference between α-asarone group and phenobarbital sodium group （P 〉 0.05）.CONCLUSION ： ① As effective anticonvulsants, both acrous gramineu and α-asarone can enhance the reactivity and convulsive threshold of immature rats to electric stimulation. ② As one of the major effective components against convulsion of acrous gramineu, α-asarone is equivalent to phenobarbital sodium.

Controllable shaping of high-index dielectric nanoparticles by exploiting the giant optical force of femtosecond laser pulses

Nanoparticles made of different materials usually support optical resonances in the visible to near infrared spectral range,such as the localized surface plasmons observed in metallic nanoparticles and the Mie resonances observed in dielectric ones.Such optical resonances,which are important for practical applications,depend strongly on the morphologies of nanoparticles.Laser irradiation is a simple but effective way to modify such optical resonances through the change in the morphology of a nanoparticle.Although laser-induced shaping of metallic nanoparticles has been successfully demonstrated,it remains a big challenge for dielectric nanoparticles due to their larger Young’s modulus and smaller thermal conductivities.Here,we proposed and demonstrated a strategy for realizing controllable shaping of high-index dielectric nanoparticles by exploiting the giant optical force induced by femtosecond laser pulses.It was found that both Si and Ge nanoparticles can be lit up by resonantly exciting the optical resonances with femtosecond laser pulses,leading to the luminescence burst when the laser power exceeds a threshold.In addition,the morphologies of Si and Ge nanoparticles can be modified by utilizing the giant absorption force exerted on them and the reduced Young’s modulus at high temperatures.The shape transformation from sphere to ellipsoid can be realized by laser irradiation,leading to the blueshifts of the optical resonances.It was found that Si and Ge nanoparticles were generally elongated along the direction parallel to the polarization of the laser light.Controllable shaping of Si and Ge can be achieved by deliberately adjusting the excitation wavelength and the laser power.Our findings are helpful for understanding the giant absorption force of femtosecond laser light and are useful for designing nanoscale photonic devices based on shaped highindex nanoparticles.

A review on sustainable reuse applications of Fenton sludge during wastewater treatment

The classical Fenton oxidation process(CFOP)is a versatile and effective application that is generally applied for recalcitrant pollutant removal.However,excess iron sludge production largely restricts its widespread application.Fenton sludge is a hazardous solid waste,which is a complex heterogeneous mixture with Fe(OH)3,organic matter,heavy metals,microorganisms,sediment impurities,and moisture.Although studies have aimed to utilize specific Fenton sludge resources based on their iron-rich characteristics,few reports have fully reviewed the utilization of Fenton sludge.As such,this review details current sustainable Fenton sludge reuse systems that are applied during wastewater treatment.Specifically,coagulant preparation,the reuse of Fenton sludge as an iron source in the Fenton process and as a synthetic heterogeneous catalyst/adsorbent,as well as the application of the Fenton sludge reuse system as a heterogeneous catalyst for resource utilization.This is the first review article to comprehensively summarize the utilization of Fenton sludge.In addition,this review suggests future research ideas to enhance the cost-effectiveness,environmental sustainability,and large-scale feasibility of Fenton sludge applications.

Optimization of cooling structures in gas turbines:A review

Attempts for higher output power and thermal efficiency of gas turbines make the inlet temperature of turbine to be far beyond the material melting temperature.Therefore,to protect the airfoil in gas turbine from hot gas and eventually prolong the lifetime of the blade,internal and film cooling structures with better thermal performance and cooling effectiveness are urgently needed.However,the traditional way of proceeding involves numerous simulations,additional experiments,and separate trials.Optimization of turbine cooling structures is an effective way to achieve better structures with higher overall performances while considering the multiple objectives,disciplines or subsystems.In this context,this paper reviews optimization research works on film cooling structures and internal cooling structures in gas turbines by means of various optimization methods.This review covers the following aspects:(A)optimization of film cooling conducted on flat plates and on turbine blades or vanes;(B)optimization of jet impingement cooling structures;(C)optimization of rib shapes,dimple shapes,pin–fin arrays in the cooling channels;(D)optimization of U-bend shaped cooling channels,and internal cooling systems of turbine blades or vanes.The review shows that through a reliable and accurate optimization procedure combined with conjugate heat transfer analysis,higher overall thermal performance can be acquired for single-objective or multi-objectives balanced by other constrained conditions.Future ways forward are pointed out in this review.

Film cooling performance and flow structure of single-hole and double-holes with swirling jet

This paper presents the results of a numerical study of the effects of swirling flow in coolant jets on film cooling performance.Some combined-hole designs with swirling coolant flow entering the delivery hole are proposed and analyzed.Adiabatic film cooling effectiveness values for cases with various blowing ratios are compared.Detailed flow structures and underlying mechanisms are discussed.The results show that film cooling effectiveness is improved with jet swirl at high blowing ratios,and that swirl strength has significant influence on film cooling performance.Combined-hole designs can further improve film cooling performance using swirling jets due to mixing of coolant flows and interaction of vortices.The largest improvements of area-averaged film cooling effectiveness for a single-hole swirl case and a combined-hole swirl case over corresponding non-swirling case results are 157%and 173%,respectively.

Effects of Chaiyuwendan decoction on endocannabinoids levels in adipose tissue of rats with chronic stress-induced depression

OBJECTIVE:To investigate how Chaiyuwendan decoction(CWD)affects endocannabinoid levels in the adipose tissue of depressed rats.METHODS:Twenty-four male Sprague-Dawley rats were randomly divided into four groups with six rats in each.One group was randomly selected as the control group.The remaining three groups were subjected to chronic stress to induce depression.Groups were randomly assigned as a model group,CWD group,and amitriptyline group.CWD was given to the CWD group once a day from the second day of modeling.The amitriptyline group was administered amitriptyline intragastrically(10 mg/kg)once a day.After treatment for 21 days,body weight and fat weight were measured and the levels of N-arachidonoylethanolamine(AEA),2-arachidonoylglycerol(2-AG),and N-palmitoylethanolamine(PEA)in adipose tissue were determined with liquid chromatography-mass spectrometry.RESULTS:Compared with the control group,body weight,fat weight,AEA,and PEA were significantly lower,and 2-AG was higher,in the model group(P<0.05,P<0.01).Compared with the model group,body weight,fat weight,the AEA,and PEA levels were significantly higher,and 2-AG level was significantly lower in the CWD group(P<0.05).However,the levels did not differ significantly between the CWD group and the amitriptyline group.CONCLUSION:CWD could regulate the levels of AEA,2-AG,and PEA in rats with depression induced by chronic stress.