The success of intelligent transportation systems relies heavily on accurate traffic prediction,in which how to model the underlying spatial-temporal information from traffic data has come under the spotlight.Most exi...The success of intelligent transportation systems relies heavily on accurate traffic prediction,in which how to model the underlying spatial-temporal information from traffic data has come under the spotlight.Most existing frameworks typically utilize separate modules for spatial and temporal correlations modeling.However,this stepwise pattern may limit the effectiveness and efficiency in spatial-temporal feature extraction and cause the overlook of important information in some steps.Furthermore,it is lacking sufficient guidance from prior information while modeling based on a given spatial adjacency graph(e.g.,deriving from the geodesic distance or approximate connectivity),and may not reflect the actual interaction between nodes.To overcome those limitations,our paper proposes a spatial-temporal graph synchronous aggregation(STGSA)model to extract the localized and long-term spatial-temporal dependencies simultaneously.Specifically,a tailored graph aggregation method in the vertex domain is designed to extract spatial and temporal features in one graph convolution process.In each STGSA block,we devise a directed temporal correlation graph to represent the localized and long-term dependencies between nodes,and the potential temporal dependence is further fine-tuned by an adaptive weighting operation.Meanwhile,we construct an elaborated spatial adjacency matrix to represent the road sensor graph by considering both physical distance and node similarity in a datadriven manner.Then,inspired by the multi-head attention mechanism which can jointly emphasize information from different r epresentation subspaces,we construct a multi-stream module based on the STGSA blocks to capture global information.It projects the embedding input repeatedly with multiple different channels.Finally,the predicted values are generated by stacking several multi-stream modules.Extensive experiments are constructed on six real-world datasets,and numerical results show that the proposed STGSA model significantly outperforms the benchmarks.展开更多
Freezing processes of several liquids under static magnetic field(SMF) less than 50 mT were investigated. Central temperature of liquid samples held in glass test tubes immersed in a liquid bath was measured and colle...Freezing processes of several liquids under static magnetic field(SMF) less than 50 mT were investigated. Central temperature of liquid samples held in glass test tubes immersed in a liquid bath was measured and collected. Nucleation temperature and phase transition time were obtained from freezing curves. Normality tests were performed for nucleation temperature of these liquids with/without magnetic field and normality distributions were justified. Analysis of variances was carried out for nucleation temperature of these liquids with magnetic field flux density as the influencing factor. Results showed that no significant difference was found for deionized water with or without SMF. However, differences exist in 0.9% NaCl solution and 5% ethylene glycol solution with and without SMF. Nucleation temperature of 0.9% NaCl with SMF is lower than that without SMF, while its phase transition time is shorter than that without SMF. Nucleation temperature of 5% ethylene glycol with SMF is higher than that without SMF, while its phase transition time is not modified with SMF.展开更多
Two novel sugar-conjugated 5-fluorocytosine(5-FC)antineoplastic compounds were designed and synthesized to improve the selective drug uptake by targeting the tumor-specific glucose transporter(GLUT).The antitumor acti...Two novel sugar-conjugated 5-fluorocytosine(5-FC)antineoplastic compounds were designed and synthesized to improve the selective drug uptake by targeting the tumor-specific glucose transporter(GLUT).The antitumor activity of these compounds was evaluated in four different human cancer cell lines:A549(human lung cancer cell line),HT29(human colorectal cancer cell line),H460(human lung cancer cell line),and PC3(human prostate cancer cell line).The sugar conjugates exhibited cytotoxicity similar to or higher than 5-FC and 1-hexylcarbamoyl-5-FC in A549,HT29,H460,and PC3.Furthermore,GLUT-mediated transport of the glycoconjugate was investigated with GLUT inhibitor-mediated cytotoxicity analysis in a GLUT-overexpressing HT29 cell line.The cell-killing potency of 5-FC glycoconjugate was found to depend significantly on the GLUT inhibitor,and the cellular uptake of molecules was regulated by GLUT-mediated transport.All the results demonstrate the potential advantages of glycoconjugation for Warburg effect-targeted drug design.展开更多
Recent studies have shown that tea polyphenols can cross the blood-brain barrier, inhibit apoptosis and play a neuroprotective role against cerebral ischemia. Furthermore, tea polyphenols can decrease DNA damage cause...Recent studies have shown that tea polyphenols can cross the blood-brain barrier, inhibit apoptosis and play a neuroprotective role against cerebral ischemia. Furthermore, tea polyphenols can decrease DNA damage caused by free radicals. We hypothesized that tea polyphenols repair DNA damage and inhibit neuronal apoptosis during global cerebral ischemia/reperfusion. To test this hypothesis, we employed a rat model of global cerebral ischemia/reperfusion. We demonstrated that intraperitoneal injection of tea polyphenols immediately after reperfusion significantly reduced apoptosis in the hippocampal CA1 region; this effect started 6 hours following reperfusion. Immunohistochemical staining showed that tea polyphenols could reverse the ischemia/reperfusion-induced reduction in the expression of DNA repair proteins, X-ray repair cross-complementing protein 1 and apudnic/apyrimidinic endonuclease/redox factor-1 starting at 2 hours. Both effects lasted at least 72 hours. These experimental findings suggest that tea polyphenols promote DNA damage repair and protect against apoptosis in the brain.展开更多
During the pupal-adult eclosion process of holometabolous insects,the old cuticle is shed and replaced by a completely different new cuticle that requires tanning and expansion,along with extensive extracellular matri...During the pupal-adult eclosion process of holometabolous insects,the old cuticle is shed and replaced by a completely different new cuticle that requires tanning and expansion,along with extensive extracellular matrix(ECM)remodeling.In vertebrates,matrix metalloproteinases(MMPs),a class of zinc-dependent endopeptidases,play key roles in regulating the ECM that surrounds cells.However,little is known about these extracellular proteinases available in insects.The small hive beetle(SHB),Aethina tumida,is a widespread invasive parasite of honey bees.In this study,6 MMP homologs were identified in the SHB genome.RNA interference experiments showed that all 6 AtMmps are not required for the larval-pupal transition,only AtMmp2 was essential for pupal-adult eclosion in SHB.Knockdown of AtMmp2 resulted in eclosion defects and wing expansion failure,as well as mortality within 3 d of adult eclosion.Transcriptomic analysis revealed that knockdown of AtMmp2 significantly increased expression of the Toll and Imd pathways,chitin metabolism,and cross-linking(such as the pro-phenoloxidase activating cascade pathway and the tyrosine-mediated cuticle sclerotization and pigmentation pathway).These data revealed evolutionarily conserved functions of Mmp2 in controlling adult eclosion and wing expansion,also provided a preliminary exploration of the novel function of regulating Toll and Imd pathways,as well as new insights into how MMPs regulate insect development and defense barriers.展开更多
Macrocycle-based glycoclusters, on account of their promising anti-adhesive properties against bacteria,are potential therapeutic alternatives to classic antibiotics through the much less explored anti-adhesive strate...Macrocycle-based glycoclusters, on account of their promising anti-adhesive properties against bacteria,are potential therapeutic alternatives to classic antibiotics through the much less explored anti-adhesive strategy. In this study, a series of constitutionally-pure pentavalent glycoclusters was prepared by conjugating assorted azido-carbohydrates onto a penta-propargyl rim-differentiated pillar[5]arene(RD-P[5])scaffold through Cu(I)-catalyzed azide–alkyne cycloaddition “click” reactions. Their binding towards therapeutically relevant bacterial lectins, such as Lec A and Lec B from Pseudomonas aeruginosa and concanavalin A(Con A), were evaluated subsequently by isothermal titration calorimetric studies. Most of these isomerfree RD-P[5] pentavalent glycoclusters, except the fucosylated ones, display good affinities to lectins.Nonetheless, the dissociation constants observed are similar to those displayed by an analogous pentavalent glycocluster consisting of four P[5] constitutional isomers, in which the RD-P[5] component merely accounts for 7% in the mixture. Our results revealed that high constitutional purity is not essential for achieving effective multivalent interactions between P[5]-based glycoclusters and lectins, presumably as a result of the conformationally labile nature of the P[5] scaffold. This information provides valuable design principles for low-cost and facile syntheses of glycosylated P[5]s for biomedical applications.展开更多
The optical nanoprobes with emissions in the second near-infrared window(NIR-Ⅱ,1000-1700 nm)show low tissue autofluorescence and photon scattering;therefore,they provide high spatial resolution and acceptable tissue ...The optical nanoprobes with emissions in the second near-infrared window(NIR-Ⅱ,1000-1700 nm)show low tissue autofluorescence and photon scattering;therefore,they provide high spatial resolution and acceptable tissue penetration depth.These advantages make them appropriate for in vivo applications,including bioimaging,NIR-Ⅱtriggered disease therapy,and even on-site efficacy monitoring.Among the various developed NIR-Ⅱfluorescence probes,lanthanide-doped nanoparticles(LDNPs)exhibit high photo stability and narrow emission bandwidths with long photoluminescence lifetimes and low cytotoxicity;therefore,they have been widely studied in the biomedical field.This review summarizes the typical compositions and optical properties of recently developed NIR-Ⅱemitting LDNPs.Their applications in in vivo NIR-Ⅱbioimaging and cancer therapy are reviewed.The perspectives and challenges of NIR-ⅡLDNPs are also discussed.展开更多
This experiment was conducted to investigate the effects of dietary arginine levels on growth performance, body composition, serum biochemical indices and resistance ability against ammonia-nitrogen stress in juvenile...This experiment was conducted to investigate the effects of dietary arginine levels on growth performance, body composition, serum biochemical indices and resistance ability against ammonia-nitrogen stress in juvenile yellow catfish(Pelteobagrus fulvidraco). Five isonitrogenous and isolipidic diets(42%protein and 9% lipid) were formulated to contain graded levels of arginine(2.44%, 2.64%, 2.81%, 3.01% and3.23% of diet), by supplementing L-Arginine HCI. Seven hundred juvenile yellow catfish with an initial average body weight of 1.13 ± 0.02 g were randomly divided into 5 groups with 4 replicates of 35 fish each and each group was fed one of the diets. After 56 d feeding, fish were exposed to 100 mg/L of ammonia-nitrogen for 72 h. The results showed that weight gain(WG) and specific growth rate(SGR) in2.64% and 2.81% groups were significantly higher than those in 3.23% group(P < 0.05). The feed conversation ratio(FCR) in 2,64%, 2,81% and 3.01% groups was significantly decreased when compared with3,23% group. The protein efficiency ratio(PER) in 2.64% group was significantly higher than that in 2.44%and 3.23% groups(P < 0.05). The condition factor(CF) of fish was significantly higher in 2.81% group than that in 2,44% group(P < 0.05). Dietary arginine levels had no significant effect on hepatosomatic index(HSI), viscerosomatic index(VSI), and whole-body dry matter, crude protein, crude lipid, ash contents, as well as serum total protein(TP), triglyceride(TG), glucose(GLU), urea nitrogen(UN) contents and aspartate aminotransferase(AST), alanine aminotransferase(ALT) activities(P> 0.05). After the fish were challenged to ammonia-nitrogen for 72 h, their cumulative mortality rate in 2.81% group was significantly lower than that in 2.44% group(P < 0.05). The results suggested that dietary arginine level at 2.81%could optimize anti-ammonia-nitrogen stress ability of juvenile yellow catfish and a level of 3.23%arginine seemed to depress the growth performance of fish and decreased their tolerance to the ammonia-nitrogen stress under current study. A quadratic regression analysis based on WG indicated that the optimal dietary arginine requirement of juvenile yellow catfish was estimated to be 2.74% of the diet(6.45% of dietary protein) under current culture conditions.展开更多
An 8-week feeding trial was conducted to evaluate the effects of sodium butyrate(SB)on growth,digestive enzymes,body composition and nutrient retention-related gene expression of juvenile yellow catfish(Pel-teobagrus ...An 8-week feeding trial was conducted to evaluate the effects of sodium butyrate(SB)on growth,digestive enzymes,body composition and nutrient retention-related gene expression of juvenile yellow catfish(Pel-teobagrus fulvidraco).Five isonitmgenous and isolipidic diets(420 g/kg protein and 90 g/kg lipid)were formulated to contain 0(control),250,500,1,000 or 2,000 mg/kg SB.Triplicate groups of 40 fish(BW=1.26±0.01 g)per tank(300-L cylindrical fiberglass tanks)for each diet were fed to apparent satiation twice daily.Stomach,hepatopancreas and intestine samples were obtained for digestive enzymes activities analyses.A real-time quantitative PCR analysis was performed to determine the relative expression of target of rapa-mycin(TOR)and lipoprotein lipase(LPL)in the hepatopancreas and intestine.Fish fed the diets supplemented with SB at 500 and 1,000 mg/kg showed significantly higher specific growth rate and significantly lower feed conversion ratio compared to the control(P<0.05).Dietary SB inclusion did not alter activities of intestinal amylase,creatine kinase and sodium-potassium adenosine triphosphatase(Na+/K+-ATPase),but increased activities of hepatic trypsin,stomachic lipase,intestinal lipase,alkaline phosphatase and y-glutamyl trans-peptidase for fish fed 1,000 mg/kg SB compared to the control(P<0.05).Intestine length index,intestine somatic index,fold height and muscular thickness of distal intestine were significantly higher in 1,000 mg/kg SB groups compared to the control(P<0.05).Significantly higher levels of whole-body crude protein,ash,calcium,phosphorus,nutrition retention and relative mRNA of intestinal TOR were observed in 1,000 mg/kg SB group(P<0.05).Whole-body lipid content and hepatopancreas LPL mRNA expression in 2,000 mg/kg SB gmup were significantly higher than the control(P<0.05).Relative mRNA levels of intestinal LPL and hepatopancreas TOR were significantly higher in the 500 mg/kg SB group compared to those in other groups(P<0.05).The increased growth performance,digestive enzymes and nutrient retention in fish fed the diets supplemented with SB at 500 and 1,000 mg/kg suggests that SB can be a desirable growth promoter as an antibiotic alternative in diets.展开更多
Brain transcriptional regulatory network for behavior demonstrates that brain gene expression in the honey bee can be accurately predicted from the expression transcription factors(TFs),but roles for specific TFs are ...Brain transcriptional regulatory network for behavior demonstrates that brain gene expression in the honey bee can be accurately predicted from the expression transcription factors(TFs),but roles for specific TFs are less understood.Mushroom bodies(MBs)are important for learning,memory and sensory integration in the honey bee brain.A TFs,Mblk-1,expressed preferentially in the large-type Kenyon cells of the honeybee MBs is predicted to be involved in brain function by regulating transcription of its target genes in honey bee.However,its function and the mechanism of regulation in behavior of honey bee is still obscure.Here we show that Mblk-1 had significantly higher expression in the brains of forager bees relative to nurse bees.Mblk-1 was significantly inhibited in bees fed small interfering RNA.In addition,inhibition of Mblk-1 decreased sucrose responsiveness in foragers.Finally,we determined that Mblk-1 regulated the messenger RNA of AmGRl.These findings suggest that Mblk-1 may target AmGRl to regulate the sucrose responsiveness of foragers.展开更多
This experiment was conducted to investigate the effects of dietary lipid-to-carbohydrate ratio on growth and carbohydrate metabolism in juvenile cobia(Rachycentron canadum).Six iso nitrogenous diets were prepared to ...This experiment was conducted to investigate the effects of dietary lipid-to-carbohydrate ratio on growth and carbohydrate metabolism in juvenile cobia(Rachycentron canadum).Six iso nitrogenous diets were prepared to vary in lipid-to-carbohydrate ratio(g/g)as follows:Dl,2.26;D2,1.31;D3,0.78;D4,0.47;D5,0.34;and D6,0.23.Cobias were fed to satiety for 8 weeks.The weight gain and protein efficiency ratio in Dl group were significantly lower than those in other groups(P<0.05),accompanied by a lower level of feed conversion ratio(P<0.05).Protein retention efficiency in D4 and D6 and whole body protein in D4 and D5 were significantly higher than those in D1 group(P<0.05).Survival rate in D4 group was the highest among all groups and was significantly higher than that in Dl,D2 and D5(P<0.05).In terms of serum triglyceride,D1 and D2 were significantly higher than D6(P<0.05).Hepatosomatic index in D3 and D4 was significantly lower than that in D1(P<0.05).Fructose-1,6-diphosphatase in D4 was significantly higher than that in D1 and D3(P<0.05).Phosphofructokinase in D3 and D4 and malic enzyme in D4 and D5 were significantly higher than those in other groups(P<0.05).Results indicate that cobia utilizes carbohydrates as energy source more efficiently than it utilizes lipids.The optimal lipid-to-carbohydrate ratio in juvenile cobia diets is 0.47.展开更多
Background:Hypocretin (HCRT) signaling plays an important role in the pathogenesis of narcolepsy and can be significantly influenced by Chinese herbal therapy.Our previous study showed that xingshentongqiao decocti...Background:Hypocretin (HCRT) signaling plays an important role in the pathogenesis of narcolepsy and can be significantly influenced by Chinese herbal therapy.Our previous study showed that xingshentongqiao decoction (XSTQ) is clinically effective for the treatment of narcolepsy.To determine whether XSTQ improves narcolepsy by modulating HCRT signaling,we investigated its effects on SH-SY5Y cell proliferation,apoptosis,and HCRT receptor 1/2 (orexin receptor 1 [OXl R] and orexin receptor 2 [OX2R]) expression.The signaling pathways involved in these processes were also assessed.Methods:The effects of XSTQ on proliferation and apoptosis in SH-SY5Y cells were assessed using cell counting kit-8 and annexin V-fluorescein isothiocyanate assays.OX1R and OX2R expression was assessed by quantitative real-time polymerase chain reaction analysis.Western blotting for mitogen-activated protein kinase (MAPK) pathway activation was performed to further assess the signaling mechanism of XSTQ.Results:XSTQ reduced the proliferation and induced apoptosis of SH-SY5Y cells.This effect was accompanied by the upregulation of OX 1R and OX2R expression and the reduced phosphorylation of extracellular signal-regulated kinase (Erk) 1/2,p38 MAPK and c-Jun N-terminal kinase (JNK).Conclusions:XSTQ inhibits proliferation and induces apoptosis in SH-SY5Y cells.XSTQ also promotes OX1R and OX2R expression.These effects are associated with the repression of the Erkl/2,p38 MAPK,and JNK signaling pathways.These results define a molecular mechanism for XSTQ in regulating HCRT and MAPK activation,which may explain its ability to treat narcolepsy.展开更多
Hypocrellin B (HB) is a highly effective photosensitizer. One of its derivatives, 5_brominated_hypocrellin B (5_Br_HB) has better photosensitive characteristics than it. Using Raman spectroscopy, the microcosmic photo...Hypocrellin B (HB) is a highly effective photosensitizer. One of its derivatives, 5_brominated_hypocrellin B (5_Br_HB) has better photosensitive characteristics than it. Using Raman spectroscopy, the microcosmic photodamage to DNA sensitized by HB and 5_Br_HB was studied at molecular level. The results showed that when HB and 5_Br_HB were added to the solution of DNA and irradiated, the characteristic Raman frequencies and intensities of DNA changed to various degrees. The photodamage occurred on the whole DNA molecule, including phosphate backbone,deoxyribose and four bases. Not only the conformation but also the configuration of DNA was photodamaged: breakage of some H_bonds, disappearance of B_form conformation , scission of double or single strand and serious damage of four bases. The damage to A_T pairs was stronger than that to C_G pairs and DNA became polynucleotides finally. The 5_Br_HB_photosensitized damage to DNA was stronger than HB , which suggested the better photosensitive characteristics of 5_Br_HB in bioactive environment. The molecular mechanisms of photodamage to DNA sensitized by 5_Br_HB and HB were also elucidated.展开更多
基金partially supported by the National Key Research and Development Program of China(2020YFB2104001)。
文摘The success of intelligent transportation systems relies heavily on accurate traffic prediction,in which how to model the underlying spatial-temporal information from traffic data has come under the spotlight.Most existing frameworks typically utilize separate modules for spatial and temporal correlations modeling.However,this stepwise pattern may limit the effectiveness and efficiency in spatial-temporal feature extraction and cause the overlook of important information in some steps.Furthermore,it is lacking sufficient guidance from prior information while modeling based on a given spatial adjacency graph(e.g.,deriving from the geodesic distance or approximate connectivity),and may not reflect the actual interaction between nodes.To overcome those limitations,our paper proposes a spatial-temporal graph synchronous aggregation(STGSA)model to extract the localized and long-term spatial-temporal dependencies simultaneously.Specifically,a tailored graph aggregation method in the vertex domain is designed to extract spatial and temporal features in one graph convolution process.In each STGSA block,we devise a directed temporal correlation graph to represent the localized and long-term dependencies between nodes,and the potential temporal dependence is further fine-tuned by an adaptive weighting operation.Meanwhile,we construct an elaborated spatial adjacency matrix to represent the road sensor graph by considering both physical distance and node similarity in a datadriven manner.Then,inspired by the multi-head attention mechanism which can jointly emphasize information from different r epresentation subspaces,we construct a multi-stream module based on the STGSA blocks to capture global information.It projects the embedding input repeatedly with multiple different channels.Finally,the predicted values are generated by stacking several multi-stream modules.Extensive experiments are constructed on six real-world datasets,and numerical results show that the proposed STGSA model significantly outperforms the benchmarks.
基金Supported by the National Natural Science Foundation of China(51306104)
文摘Freezing processes of several liquids under static magnetic field(SMF) less than 50 mT were investigated. Central temperature of liquid samples held in glass test tubes immersed in a liquid bath was measured and collected. Nucleation temperature and phase transition time were obtained from freezing curves. Normality tests were performed for nucleation temperature of these liquids with/without magnetic field and normality distributions were justified. Analysis of variances was carried out for nucleation temperature of these liquids with magnetic field flux density as the influencing factor. Results showed that no significant difference was found for deionized water with or without SMF. However, differences exist in 0.9% NaCl solution and 5% ethylene glycol solution with and without SMF. Nucleation temperature of 0.9% NaCl with SMF is lower than that without SMF, while its phase transition time is shorter than that without SMF. Nucleation temperature of 5% ethylene glycol with SMF is higher than that without SMF, while its phase transition time is not modified with SMF.
基金supported by the National Natural Science Foundation of China (No. 21772144 and No. 21801184)Tianjin Municipal Applied Basic and Key Research Scheme, China (No. 18JCQNIC06400)
文摘Two novel sugar-conjugated 5-fluorocytosine(5-FC)antineoplastic compounds were designed and synthesized to improve the selective drug uptake by targeting the tumor-specific glucose transporter(GLUT).The antitumor activity of these compounds was evaluated in four different human cancer cell lines:A549(human lung cancer cell line),HT29(human colorectal cancer cell line),H460(human lung cancer cell line),and PC3(human prostate cancer cell line).The sugar conjugates exhibited cytotoxicity similar to or higher than 5-FC and 1-hexylcarbamoyl-5-FC in A549,HT29,H460,and PC3.Furthermore,GLUT-mediated transport of the glycoconjugate was investigated with GLUT inhibitor-mediated cytotoxicity analysis in a GLUT-overexpressing HT29 cell line.The cell-killing potency of 5-FC glycoconjugate was found to depend significantly on the GLUT inhibitor,and the cellular uptake of molecules was regulated by GLUT-mediated transport.All the results demonstrate the potential advantages of glycoconjugation for Warburg effect-targeted drug design.
基金supported by the National Natural Science Foundation of China, No. 30571790
文摘Recent studies have shown that tea polyphenols can cross the blood-brain barrier, inhibit apoptosis and play a neuroprotective role against cerebral ischemia. Furthermore, tea polyphenols can decrease DNA damage caused by free radicals. We hypothesized that tea polyphenols repair DNA damage and inhibit neuronal apoptosis during global cerebral ischemia/reperfusion. To test this hypothesis, we employed a rat model of global cerebral ischemia/reperfusion. We demonstrated that intraperitoneal injection of tea polyphenols immediately after reperfusion significantly reduced apoptosis in the hippocampal CA1 region; this effect started 6 hours following reperfusion. Immunohistochemical staining showed that tea polyphenols could reverse the ischemia/reperfusion-induced reduction in the expression of DNA repair proteins, X-ray repair cross-complementing protein 1 and apudnic/apyrimidinic endonuclease/redox factor-1 starting at 2 hours. Both effects lasted at least 72 hours. These experimental findings suggest that tea polyphenols promote DNA damage repair and protect against apoptosis in the brain.
基金funded by GDAS Special Project of Science and Technology Development(2022GDASZH-2022010106)National Natural Science Foundation of China(Grant No.32200405),Guangzhou Basic and Applied Basic Research Foundation(202201010255)+1 种基金Guangdong Basic and Applied Basic Research Foundation(2021A1515012102,2021A1515010630)Science and Technology Planning Project of Yunfu City(2022020425).
文摘During the pupal-adult eclosion process of holometabolous insects,the old cuticle is shed and replaced by a completely different new cuticle that requires tanning and expansion,along with extensive extracellular matrix(ECM)remodeling.In vertebrates,matrix metalloproteinases(MMPs),a class of zinc-dependent endopeptidases,play key roles in regulating the ECM that surrounds cells.However,little is known about these extracellular proteinases available in insects.The small hive beetle(SHB),Aethina tumida,is a widespread invasive parasite of honey bees.In this study,6 MMP homologs were identified in the SHB genome.RNA interference experiments showed that all 6 AtMmps are not required for the larval-pupal transition,only AtMmp2 was essential for pupal-adult eclosion in SHB.Knockdown of AtMmp2 resulted in eclosion defects and wing expansion failure,as well as mortality within 3 d of adult eclosion.Transcriptomic analysis revealed that knockdown of AtMmp2 significantly increased expression of the Toll and Imd pathways,chitin metabolism,and cross-linking(such as the pro-phenoloxidase activating cascade pathway and the tyrosine-mediated cuticle sclerotization and pigmentation pathway).These data revealed evolutionarily conserved functions of Mmp2 in controlling adult eclosion and wing expansion,also provided a preliminary exploration of the novel function of regulating Toll and Imd pathways,as well as new insights into how MMPs regulate insect development and defense barriers.
基金Financial supports from the National Natural Science Foundation of China (No. 21801184)the Tianjin Municipal Applied Basic and Key Research Scheme of China (No. 18JCQNJC06400)+3 种基金Xiamen University, Starry Night Science Fund of Zhejiang University Shanghai Institute for Advanced Study (No. SN-ZJU-SIAS-006)Université de Lyon, the French Agence Nationale de la Recherche (Dyna Sweet, ANR-08-BLAN-0305)Glyco@Alps (ANR-15-IDEX-02)Labex Arcane/CBH-EUR-GS (ANR-17-EURE-0003) are gratefully acknowledged。
文摘Macrocycle-based glycoclusters, on account of their promising anti-adhesive properties against bacteria,are potential therapeutic alternatives to classic antibiotics through the much less explored anti-adhesive strategy. In this study, a series of constitutionally-pure pentavalent glycoclusters was prepared by conjugating assorted azido-carbohydrates onto a penta-propargyl rim-differentiated pillar[5]arene(RD-P[5])scaffold through Cu(I)-catalyzed azide–alkyne cycloaddition “click” reactions. Their binding towards therapeutically relevant bacterial lectins, such as Lec A and Lec B from Pseudomonas aeruginosa and concanavalin A(Con A), were evaluated subsequently by isothermal titration calorimetric studies. Most of these isomerfree RD-P[5] pentavalent glycoclusters, except the fucosylated ones, display good affinities to lectins.Nonetheless, the dissociation constants observed are similar to those displayed by an analogous pentavalent glycocluster consisting of four P[5] constitutional isomers, in which the RD-P[5] component merely accounts for 7% in the mixture. Our results revealed that high constitutional purity is not essential for achieving effective multivalent interactions between P[5]-based glycoclusters and lectins, presumably as a result of the conformationally labile nature of the P[5] scaffold. This information provides valuable design principles for low-cost and facile syntheses of glycosylated P[5]s for biomedical applications.
基金National Natural Science Foundation of China,Grant/Award Numbers:21890741,21974064,22022405Natural Science Foundation of Jiangsu Province,Grant/Award Number:BK20200010State Key Laboratory of Analytical Chemistry for Life Sciences,Grant/Award Numbers:5431ZZXM2204,5431ZZXM2307。
文摘The optical nanoprobes with emissions in the second near-infrared window(NIR-Ⅱ,1000-1700 nm)show low tissue autofluorescence and photon scattering;therefore,they provide high spatial resolution and acceptable tissue penetration depth.These advantages make them appropriate for in vivo applications,including bioimaging,NIR-Ⅱtriggered disease therapy,and even on-site efficacy monitoring.Among the various developed NIR-Ⅱfluorescence probes,lanthanide-doped nanoparticles(LDNPs)exhibit high photo stability and narrow emission bandwidths with long photoluminescence lifetimes and low cytotoxicity;therefore,they have been widely studied in the biomedical field.This review summarizes the typical compositions and optical properties of recently developed NIR-Ⅱemitting LDNPs.Their applications in in vivo NIR-Ⅱbioimaging and cancer therapy are reviewed.The perspectives and challenges of NIR-ⅡLDNPs are also discussed.
基金supported by the National Natural Science Foundation of China (31402307)the construction of public service platform for the evaluation of the value of aquatic feed and feed additives in Guangdong Province(2015A040404033)
文摘This experiment was conducted to investigate the effects of dietary arginine levels on growth performance, body composition, serum biochemical indices and resistance ability against ammonia-nitrogen stress in juvenile yellow catfish(Pelteobagrus fulvidraco). Five isonitrogenous and isolipidic diets(42%protein and 9% lipid) were formulated to contain graded levels of arginine(2.44%, 2.64%, 2.81%, 3.01% and3.23% of diet), by supplementing L-Arginine HCI. Seven hundred juvenile yellow catfish with an initial average body weight of 1.13 ± 0.02 g were randomly divided into 5 groups with 4 replicates of 35 fish each and each group was fed one of the diets. After 56 d feeding, fish were exposed to 100 mg/L of ammonia-nitrogen for 72 h. The results showed that weight gain(WG) and specific growth rate(SGR) in2.64% and 2.81% groups were significantly higher than those in 3.23% group(P < 0.05). The feed conversation ratio(FCR) in 2,64%, 2,81% and 3.01% groups was significantly decreased when compared with3,23% group. The protein efficiency ratio(PER) in 2.64% group was significantly higher than that in 2.44%and 3.23% groups(P < 0.05). The condition factor(CF) of fish was significantly higher in 2.81% group than that in 2,44% group(P < 0.05). Dietary arginine levels had no significant effect on hepatosomatic index(HSI), viscerosomatic index(VSI), and whole-body dry matter, crude protein, crude lipid, ash contents, as well as serum total protein(TP), triglyceride(TG), glucose(GLU), urea nitrogen(UN) contents and aspartate aminotransferase(AST), alanine aminotransferase(ALT) activities(P> 0.05). After the fish were challenged to ammonia-nitrogen for 72 h, their cumulative mortality rate in 2.81% group was significantly lower than that in 2.44% group(P < 0.05). The results suggested that dietary arginine level at 2.81%could optimize anti-ammonia-nitrogen stress ability of juvenile yellow catfish and a level of 3.23%arginine seemed to depress the growth performance of fish and decreased their tolerance to the ammonia-nitrogen stress under current study. A quadratic regression analysis based on WG indicated that the optimal dietary arginine requirement of juvenile yellow catfish was estimated to be 2.74% of the diet(6.45% of dietary protein) under current culture conditions.
基金the National Natural Science Foundation of China(31402307)modern agricultural technology extension system construction project of Guangdong Province(2019KJ115)+1 种基金Science and Technology Planning Project of Guangdong Province(2019A050505007)discipline team building projects of Guangdong Academy of Agricultural Sciences in the 13th Five-Year Period(201614TD).
文摘An 8-week feeding trial was conducted to evaluate the effects of sodium butyrate(SB)on growth,digestive enzymes,body composition and nutrient retention-related gene expression of juvenile yellow catfish(Pel-teobagrus fulvidraco).Five isonitmgenous and isolipidic diets(420 g/kg protein and 90 g/kg lipid)were formulated to contain 0(control),250,500,1,000 or 2,000 mg/kg SB.Triplicate groups of 40 fish(BW=1.26±0.01 g)per tank(300-L cylindrical fiberglass tanks)for each diet were fed to apparent satiation twice daily.Stomach,hepatopancreas and intestine samples were obtained for digestive enzymes activities analyses.A real-time quantitative PCR analysis was performed to determine the relative expression of target of rapa-mycin(TOR)and lipoprotein lipase(LPL)in the hepatopancreas and intestine.Fish fed the diets supplemented with SB at 500 and 1,000 mg/kg showed significantly higher specific growth rate and significantly lower feed conversion ratio compared to the control(P<0.05).Dietary SB inclusion did not alter activities of intestinal amylase,creatine kinase and sodium-potassium adenosine triphosphatase(Na+/K+-ATPase),but increased activities of hepatic trypsin,stomachic lipase,intestinal lipase,alkaline phosphatase and y-glutamyl trans-peptidase for fish fed 1,000 mg/kg SB compared to the control(P<0.05).Intestine length index,intestine somatic index,fold height and muscular thickness of distal intestine were significantly higher in 1,000 mg/kg SB groups compared to the control(P<0.05).Significantly higher levels of whole-body crude protein,ash,calcium,phosphorus,nutrition retention and relative mRNA of intestinal TOR were observed in 1,000 mg/kg SB group(P<0.05).Whole-body lipid content and hepatopancreas LPL mRNA expression in 2,000 mg/kg SB gmup were significantly higher than the control(P<0.05).Relative mRNA levels of intestinal LPL and hepatopancreas TOR were significantly higher in the 500 mg/kg SB group compared to those in other groups(P<0.05).The increased growth performance,digestive enzymes and nutrient retention in fish fed the diets supplemented with SB at 500 and 1,000 mg/kg suggests that SB can be a desirable growth promoter as an antibiotic alternative in diets.
基金This work was supported by the Natural Science Foundation of Guangdong Province(2021A1515010630,2021A1515012102)GDAS Special Project of Science and Technology Development(2021GDASYL-20210103053)China Agriculture Research System(CARS-44-SYZ11).
文摘Brain transcriptional regulatory network for behavior demonstrates that brain gene expression in the honey bee can be accurately predicted from the expression transcription factors(TFs),but roles for specific TFs are less understood.Mushroom bodies(MBs)are important for learning,memory and sensory integration in the honey bee brain.A TFs,Mblk-1,expressed preferentially in the large-type Kenyon cells of the honeybee MBs is predicted to be involved in brain function by regulating transcription of its target genes in honey bee.However,its function and the mechanism of regulation in behavior of honey bee is still obscure.Here we show that Mblk-1 had significantly higher expression in the brains of forager bees relative to nurse bees.Mblk-1 was significantly inhibited in bees fed small interfering RNA.In addition,inhibition of Mblk-1 decreased sucrose responsiveness in foragers.Finally,we determined that Mblk-1 regulated the messenger RNA of AmGRl.These findings suggest that Mblk-1 may target AmGRl to regulate the sucrose responsiveness of foragers.
基金supported by the modern agricultural technology extension system construction project of Guangdong Province(2018LM0822018LM083+1 种基金2019KJ115)the team building project of Guangdong academy of agricultural Sciences(201614TD).
文摘This experiment was conducted to investigate the effects of dietary lipid-to-carbohydrate ratio on growth and carbohydrate metabolism in juvenile cobia(Rachycentron canadum).Six iso nitrogenous diets were prepared to vary in lipid-to-carbohydrate ratio(g/g)as follows:Dl,2.26;D2,1.31;D3,0.78;D4,0.47;D5,0.34;and D6,0.23.Cobias were fed to satiety for 8 weeks.The weight gain and protein efficiency ratio in Dl group were significantly lower than those in other groups(P<0.05),accompanied by a lower level of feed conversion ratio(P<0.05).Protein retention efficiency in D4 and D6 and whole body protein in D4 and D5 were significantly higher than those in D1 group(P<0.05).Survival rate in D4 group was the highest among all groups and was significantly higher than that in Dl,D2 and D5(P<0.05).In terms of serum triglyceride,D1 and D2 were significantly higher than D6(P<0.05).Hepatosomatic index in D3 and D4 was significantly lower than that in D1(P<0.05).Fructose-1,6-diphosphatase in D4 was significantly higher than that in D1 and D3(P<0.05).Phosphofructokinase in D3 and D4 and malic enzyme in D4 and D5 were significantly higher than those in other groups(P<0.05).Results indicate that cobia utilizes carbohydrates as energy source more efficiently than it utilizes lipids.The optimal lipid-to-carbohydrate ratio in juvenile cobia diets is 0.47.
文摘Background:Hypocretin (HCRT) signaling plays an important role in the pathogenesis of narcolepsy and can be significantly influenced by Chinese herbal therapy.Our previous study showed that xingshentongqiao decoction (XSTQ) is clinically effective for the treatment of narcolepsy.To determine whether XSTQ improves narcolepsy by modulating HCRT signaling,we investigated its effects on SH-SY5Y cell proliferation,apoptosis,and HCRT receptor 1/2 (orexin receptor 1 [OXl R] and orexin receptor 2 [OX2R]) expression.The signaling pathways involved in these processes were also assessed.Methods:The effects of XSTQ on proliferation and apoptosis in SH-SY5Y cells were assessed using cell counting kit-8 and annexin V-fluorescein isothiocyanate assays.OX1R and OX2R expression was assessed by quantitative real-time polymerase chain reaction analysis.Western blotting for mitogen-activated protein kinase (MAPK) pathway activation was performed to further assess the signaling mechanism of XSTQ.Results:XSTQ reduced the proliferation and induced apoptosis of SH-SY5Y cells.This effect was accompanied by the upregulation of OX 1R and OX2R expression and the reduced phosphorylation of extracellular signal-regulated kinase (Erk) 1/2,p38 MAPK and c-Jun N-terminal kinase (JNK).Conclusions:XSTQ inhibits proliferation and induces apoptosis in SH-SY5Y cells.XSTQ also promotes OX1R and OX2R expression.These effects are associated with the repression of the Erkl/2,p38 MAPK,and JNK signaling pathways.These results define a molecular mechanism for XSTQ in regulating HCRT and MAPK activation,which may explain its ability to treat narcolepsy.
文摘Hypocrellin B (HB) is a highly effective photosensitizer. One of its derivatives, 5_brominated_hypocrellin B (5_Br_HB) has better photosensitive characteristics than it. Using Raman spectroscopy, the microcosmic photodamage to DNA sensitized by HB and 5_Br_HB was studied at molecular level. The results showed that when HB and 5_Br_HB were added to the solution of DNA and irradiated, the characteristic Raman frequencies and intensities of DNA changed to various degrees. The photodamage occurred on the whole DNA molecule, including phosphate backbone,deoxyribose and four bases. Not only the conformation but also the configuration of DNA was photodamaged: breakage of some H_bonds, disappearance of B_form conformation , scission of double or single strand and serious damage of four bases. The damage to A_T pairs was stronger than that to C_G pairs and DNA became polynucleotides finally. The 5_Br_HB_photosensitized damage to DNA was stronger than HB , which suggested the better photosensitive characteristics of 5_Br_HB in bioactive environment. The molecular mechanisms of photodamage to DNA sensitized by 5_Br_HB and HB were also elucidated.