Objective： This paper was designed to confirm the efficacy of chewing carboxymethyl chitosan（CMCTS）-containing gum in suppressing the growth of oral bacteria when compared to a CMCTS-containing mouth rinse. Methods...Objective： This paper was designed to confirm the efficacy of chewing carboxymethyl chitosan（CMCTS）-containing gum in suppressing the growth of oral bacteria when compared to a CMCTS-containing mouth rinse. Methods：Fourteen healthy subjects were recruited from among the staff and students of Qingdao University Dentistry Department. Before the experiments saliva was collected from all subjects and bacteria counts determined. For the gum study, the subjects chewed CMCTS-containing gum for 5 min and then rested for 5 min. When testing the CMCTS mouth rinse, the subjects gargled with 10 mL of solution for 30 s, followed by resting for 9rain 30 s. These protocols were repeated five times over a 50 min period on the same day. Post-experiment saliva samples were then collected at the following times： 0, 30 and 60 min. Results： Chewing gum containing CMCTS or rinsing with a CMCTS-containing rinse significantly decreased oral bacteria counts. The total bacteria counts, total Streptococci counts, and mutans streptococci counts of saliva from subjects who chewed CMCTS-containing gum were significantly lower than saliva from subjects in the rinse group in all three sampling periods, except in the case of the total bacteria count in the 60 min samples. Conclusion：CMCTS-containing gum chewing has a greater antibac- terial effect than using a CMCTS-containing mouth rinse. The present findings strongly indicate that the application of natural materials such as chitosan and its derivatives is useful for better oral health.展开更多
Inflammatory orofacial pain,in which substance P (SP) plays an important role,is closely related to the cross-talk between trigeminal ganglion (TG) neurons and satellite glial cells (SGCs).SGC activation is emerging a...Inflammatory orofacial pain,in which substance P (SP) plays an important role,is closely related to the cross-talk between trigeminal ganglion (TG) neurons and satellite glial cells (SGCs).SGC activation is emerging as the key mechanism underlying inflammatory pain through different signalling mechanisms,including glial fibrillary acidic protein (GFAP) activation,phosphorylation of mitogen-activated protein kinase (MAPK) signalling pathways,and cytokine upregulation.However,in the TG,the mechanism underlying SP-mediated orofacial pain generated by SGCs is largely unknown.In this study,we investigated whether SP is involved in inflammatory orofacial pain by upregulating interleukin (IL)-1β and tumour necrosis factor (TNF)-α from SGCs,and we explored whether MAPK signalling pathways mediate the pain process.In the present study,complete Freund’s adjuvant (CFA) was injected into the whisker pad of rats to induce an inflammatory model in vivo.SP was administered to SGC cultures in vitro to confirm the effect of SP.Facial expression analysis showed that pre-injection of L703,606 (an NK-1 receptor antagonist),U0126 (an inhibitor of MAPK/extracellular signal-regulated kinase [ERK] kinase [MEK] 1/2),and SB203580 (an inhibitor of P38) into the TG to induce targeted prevention of the activation of the NK-1 receptor and the phosphorylation of MAPKs significantly suppressed CFA-induced inflammatory allodynia.In addition,SP promoted SGC activation,which was proven by increased GFAP,p-MAPKs,IL-1β and TNF-α in SGCs under inflammatory conditions.Moreover,the increase in IL-1β and TNF-α was suppressed by L703,606,U0126 and SB203580 in vivo and in vitro.These present findings suggested that SP,released from TG neurons,activated SGCs through the ERK1/2 and P38 pathways and promoted the production of IL-1β and TNF-α from SGCs,contributing to inflammatory orofacial pain associated with peripheral sensitization.展开更多
BACKGROUND:Nerve invasion is a specific type of tumor expansion and characteristic manifestation of pancreatic cancer(PC),with an incidence rate ranging from 50% to 100%.It is an important prognostic factor for pancre...BACKGROUND:Nerve invasion is a specific type of tumor expansion and characteristic manifestation of pancreatic cancer(PC),with an incidence rate ranging from 50% to 100%.It is an important prognostic factor for pancreatic cancer,and its early detection is helpful in the management of the disease.This study was undertaken to analyze retrospectively the relationship between neural invasion and multiple clinicopathological features and to provide evidences for clinicians in the management of neural invasion in patients with PC.METHODS:Formalin-fixed paraffin-embeded specimens of PC taken from 215 patients were examined for the presence of neural invasion under a light microscope.Analyzed was the relationship between neural invasion and multiple clinicopathological feature including preoperative fasting blood glucose level,amylase level,serum CA19-9 level,abdominal pain,lumbar and back pain,and the expressions of p53 and Ki67 in tumor tissues.RESULTS:Preoperative fasting blood glucose level,serum CA19-9 level and p53 positive cells in cancer tissue were increased with the rise of pathological grade(P【0.05).These indices were significantly higher in patients with neural invasion than in those without(P【0.05).Further analysis revealed a positive correlation between p53 and Ki67 overexpression and lymphatic metastasis(P【0.05).Referred pain was positively correlated with neural invasion(P【0.05).Patients with PC perineural invasion were more likely to have a higher pathological grade(P【0.05).CONCLUSIONS:Our data indicated that the preoperative fasting blood glucose level,serum CA19-9 level,and referred pain are novel predictive markers for neural invasion in patients with PC.p53 and Ki67 play important roles in neural invasion of PC.Management of hyperglycemia may serve as an auxiliary treatment to curb neural invasion in PC.展开更多
Chlorogenic acid（5-caffeoylquinic acid, CGA） is a phenolic compound that is found ubiquitously in plants, fruits and vegetables and is formed via the esterification of caffeic acid and quinic acid. In addition to it...Chlorogenic acid（5-caffeoylquinic acid, CGA） is a phenolic compound that is found ubiquitously in plants, fruits and vegetables and is formed via the esterification of caffeic acid and quinic acid. In addition to its notable biological functions against cardiovascular diseases, type-2 diabetes and inflammatory conditions, CGA was recently hypothesized to be an alternative for the treatment of neurological diseases such as Alzheimer＇s disease and neuropathic pain disorders. However, its mechanism of action is unclear.Voltage-gated potassium channel（Kv） is a crucial factor in the electro-physiological processes of sensory neurons. Kv has also been identified as a potential therapeutic target for inflammation and neuropathic pain disorders. In this study, we analysed the effects of CGA on the two main subtypes of Kv in trigeminal ganglion neurons, namely, the IK,Aand IK,Vchannels. Trigeminal ganglion（TRG）neurons were acutely disassociated from the rat TRG, and two different doses of CGA（0.2 and 1 mmol·L21） were applied to the cells.Whole-cell patch-clamp recordings were performed to observe alterations in the activation and inactivation properties of the IK,Aand IK,Vchannels. The results demonstrated that 0.2 mmol·L21CGA decreased the peak current density of IK,A. Both 0.2 mmol·L21and1 mmol·L21CGA also caused a significant reduction in the activation and inactivation thresholds of IK,Aand IK,V. CGA exhibited a strong effect on the activation and inactivation velocities of IK,Aand IK,V. These findings provide novel evidence explaining the biological effects of CGA, especially regarding its neurological effects.展开更多
The keeper and cast dowel-coping, as a primary component for a magnetic attachment, is easily subjected to corrosion in a wet environment, such as the oral cavity, which contains electrolyte-rich saliva, complex micro...The keeper and cast dowel-coping, as a primary component for a magnetic attachment, is easily subjected to corrosion in a wet environment, such as the oral cavity, which contains electrolyte-rich saliva, complex microflora and chewing behaviour and so on. The objective of this in vitro study was to examine the corrosion resistance of a dowel and coping-keeper complex fabricated by finish keeper and three alloys （cobalt-chromium, CoCr; silver-palladium-gold, PdAu; gold-platinum, AuPt） using a laser- welding process and a casting technique. The surface morphology characteristics and microstructures of the samples were examined by means of metallographic microscope and scanning electron microscope （SEM）. Energy-dispersive spectroscopy （EDS） with SEM provided elements analysis information for the test samples after 10% oxalic acid solution etching test. Tafel polarization curve recordings demonstrated parameter values indicating corrosion of the samples when subjected to electrochemical testing. This study has suggested that massive oxides are attached to the surface of the CoCr-keeper complex but not to the AuPt-keeper complex. Only the keeper area of cast CoCr-keeper complex displayed obvious intergranular corrosion and changes in the Fe and Co elements, Both cast and laser-welded AuPt-keeper complexes had the highest free corrosion potential, followed by the PdAu-keeper complex. We concluded that although the corrosion resistance of the CoCr-keeper complex was worst, the keeper surface passive film was actually preserved to its maximum extent. The laser-welded CoCr- and PdAu-keeper complexes possessed superior corrosion resistance as compared with their cast specimens, but no significant difference was found between the cast and laser-welded AuPt-keeper complexes. The Fe-poor and Cr-rich band, appearing on the edge of the keeper when casting, has been proven to be a corrosion-prone area.展开更多
Objective: To evaluate the value of MSCT plain scan and enhanced CT in the diagnosis of thymic adenocarcinoma. Methods: From May 2013 to June 2018, 37 cases of MSCT plain scan and dual-phase enhanced scan of thymic ad...Objective: To evaluate the value of MSCT plain scan and enhanced CT in the diagnosis of thymic adenocarcinoma. Methods: From May 2013 to June 2018, 37 cases of MSCT plain scan and dual-phase enhanced scan of thymic adenocarcinoma were retrospectively analyzed. The location, shape, size, density (CT value), enhanced features, peripheral invasion and mediastinal lymph node metastasis of the lesions were observed. Results: All 37 cases of thymic adenocarcinoma were diagnosed by CT before operation, and all cases were diagnosed by pathology after operation as malignant tumors,including 28 cases of thoracic adenocarcinoma and 9 cases of invasive thymoma. All 28 cases of thymic adenocarcinoma were single lesion of anterior superior mediastinum. The maximum cross-section was located in the midline in 7 cases and on the mediastinal side in 21 cases with significant difference (P<0.05). All lesions were irregular lobulated. The minimum diameter of lesions was 2.1 cm and the maximum diameter was 8.6 cm. Soft tissue density was dominant in the solid part. All cases of thymic adenocarcinoma showed inhomogeneous, moderate and severe enhancement in the arterial and venous phase after enhancement. The degree of enhancement in the venous phase was higher than that in the arterial phase, and there was no enhancement in the irregular liquefied necrosis area. 26 cases had necrotic lesions, 21 cases had mediastinal lymph node metastasis, and 8 cases had invasion of adjacent pleura. 19 cases had mediastinal vessels and 0 cases had distant pleural metastases. Conclusion: MSCT plain scan combined with dual-phase enhanced CT is helpful to display the details and metastasis of thymic adenocarcinoma, improve the coincidence rate of CT diagnosis and pathological diagnosis, and reduce the misdiagnosis rate. To provide help for clinical diagnosis and treatment of thymic adenocarcinoma.展开更多
The application of light-weight current collectors is preferred because of the increased energy density of the batteries.Bearing it in mind,the cathode is designed with self-made paperlike memberane as current collect...The application of light-weight current collectors is preferred because of the increased energy density of the batteries.Bearing it in mind,the cathode is designed with self-made paperlike memberane as current collector coupled with another interlayer to enable the high-energy-density lithium-sulfur batteries.Via a facile and green step-by-step methodology,the hybrid membrane is finalized successfully,consisting of reduced graphene oxide sheets covering paper-derived carbon(GPC)bearing Fe@Fe2O3 and Fe1−xS@Fe2O3 core-shell nanoparticles(FeFeO/FeSFeO@GPC).The film works as the current collector and interlayer simultaneously considering the porous and conductive features.As demonstrated by the electrochemical testing,the FeFeO/FeSFeO@GPC hybrid cell exhibits attractive cycling stability and superior rate capability.The cell configuration and structural/composition merits of FeFeO/FeSFeO@GPC film facilitate the faster reaction kinetics,conducive to the improvement of capacity retention.In view of the effective cathode design,the areal sulfur loading is increased to 10.46 mg·cm^(−2)and a reversible capacity of 6.67 mAh·cm^(−2)can be retained after 60 cycles at 0.1 C.展开更多
Neuroinflammation and a-synuclein (a-syn) aggregation are both neuropathological hallmarks of Parkinson’s disease (PD). Microglia are crucial participants in eliciting neuroinflammatory responses themselves, as well ...Neuroinflammation and a-synuclein (a-syn) aggregation are both neuropathological hallmarks of Parkinson’s disease (PD). Microglia are crucial participants in eliciting neuroinflammatory responses themselves, as well as modulating neurotoxic activity in astrocytes, therefore forming a pathway to neurodegeneration induced by both central and peripheral insults [1, 2].展开更多
Misfoldedα-synuclein(α-syn)hallmarks the neuropathological characteristics of Parkinson's disease(PD)and acts as a"pathological seed"that promotes the progression of the disease[1].About 15%of PD patie...Misfoldedα-synuclein(α-syn)hallmarks the neuropathological characteristics of Parkinson's disease(PD)and acts as a"pathological seed"that promotes the progression of the disease[1].About 15%of PD patients have a family history,5%-10%have a monogenic disorder with a Mendelian pattern of inheritance[2],and>90 independent risk signals identified by genome-wide association studies(GWASs)can be used to explain the non-monogenic risk of PD[3].展开更多
The use of transition-metal phosphides(TMPs)as catalytic materials to accelerate kinetics of lithium polysulfide(LiPS)conversion has unique advantages.Nevertheless,simple and low-cost preparation strategies are still ...The use of transition-metal phosphides(TMPs)as catalytic materials to accelerate kinetics of lithium polysulfide(LiPS)conversion has unique advantages.Nevertheless,simple and low-cost preparation strategies are still required for the synthesis of novel TMPs with satisfactory performance.Importantly,the in-depth understanding of the effect of intrinsic interaction between catalytic materials and LiPSs on the promoted kinetics remains limited.Herein,a novel structure of tungsten phosphide(WP)nanocrystals decorated on N,P codoped carbon sheets(WP/NPC)with uniform dispersion is designed by a structure-oriented strategy to promote LiPS redox kinetics.The electrochemical kinetics measurements coupled with density functional theory computations and in situ/ex situ characterizations demonstrate that the strong interaction through W–S bonding and the favorable interfacial charge state of WP-LiPSs promote the nucleation and dissociation of Li2S.Benefiting from this superiority,the WP/NPG-based lithium–sulfur batteries indicate significantly improved electrochemical performance with good cycling life and excellent rate capability.This work provides a methodology for the design of TMP-involved electrode materials and a fundamental understanding of the intrinsic mechanism of catalysis.展开更多
CRISPR/Cas （clustered regularly interspaced short palindromic repeats/CR1SPR-associated proteins） is an adaptive immune system in bacteria and archaea to defend against invasion from foreign DNA fragments. Recently,...CRISPR/Cas （clustered regularly interspaced short palindromic repeats/CR1SPR-associated proteins） is an adaptive immune system in bacteria and archaea to defend against invasion from foreign DNA fragments. Recently, it has been developed as a powerful targeted genome editing tool for a wide variety of species. However, its application in maize has only been tested with transiently expressed somatic cells or with a limited number of stable transgenic To plants. The exact efficiency and specificity of the CRISPR/Cas system in the highly complex maize genome has not been documented yet. Here we report an extensive study of the well-studied type II CRISPR-Cas9 system for targeted genome editing in maize, with the codon-optimized Cas9 protein and the short non-coding guide RNA generated through a functional maize U6 snRNA promoter. Targeted gene mutagenesis was detected for 90 loci by maize protoplast assay, with an average cleavage efficiency of 10.67 %. Stable knockout transformants for maize phytoene synthase gene （PSYI） were obtained. Mutations occurred in germ ceils can be stably inherited to the next generation. Moreover, no off-target effect was detected at the computationally predicted putative off-target loci. No significant difference between the transcriptomes of the Cas9 expressed and non-expressed lines was detected. Our results confirmed that the CRISPR-Cas9 could be successfully applied as a robust targeted genome editing system in maize.展开更多
Parkinson’s disease(PD)is recognized as the second most common neurodegenerative disorder after Alzheimer disease.Although a fascinating 200-year journey of research has revealed the multifaceted nature of PD[1,2],it...Parkinson’s disease(PD)is recognized as the second most common neurodegenerative disorder after Alzheimer disease.Although a fascinating 200-year journey of research has revealed the multifaceted nature of PD[1,2],its fundamental features are the loss of dopaminergic neurons in the substantia nigra pars compacta(SNpc)and depletion of dopamine(DA)in the striatum.Iron accumulates in normal brains with aging.Such展开更多
Eukaryotic initiation factor subunit c(eIF3c) has been identified as an oncogene that is over-expressed in tumor cells and,therefore,is a potential therapeutic target for gene-based cancer treatment.This study was foc...Eukaryotic initiation factor subunit c(eIF3c) has been identified as an oncogene that is over-expressed in tumor cells and,therefore,is a potential therapeutic target for gene-based cancer treatment.This study was focused on investigating the effect of small interfering RNA(siRNA)-mediated eIF3c gene knockdown on colon cancer cell survival.The eIF3c gene was observed to be highly expressed in colon cancer cell models.The expression levels of the gene in eIF3c siRNA infected and control siRNA infected cells were compared via real-time polymerase chain reaction(PCR) and western blotting analysis.Cell proliferation levels were analyzed employing 3-(4,5-dimethylthiazol 2-yl)-2,5-diphenyltetrazolium bromide(MTT) and colony formation assays.Furthermore,the effects of eIF3c gene knockdown on the cell cycle and apoptosis were analyzed using flow cytometry.The results showed that suppression of eIF3c expression significantly(P<0.001) reduced cell proliferation and colony formation of RKO colon cancer cells.The cell cycle was arrested by decreasing the number of cells entering S phase.Further,apoptosis was induced as a result of eIF3c knockdown.Collectively,eIF3c deletion effectively reduced the survival of colon cancer cells and could be used as a therapeutic tool for colon cancer therapy.展开更多
文摘Objective： This paper was designed to confirm the efficacy of chewing carboxymethyl chitosan（CMCTS）-containing gum in suppressing the growth of oral bacteria when compared to a CMCTS-containing mouth rinse. Methods：Fourteen healthy subjects were recruited from among the staff and students of Qingdao University Dentistry Department. Before the experiments saliva was collected from all subjects and bacteria counts determined. For the gum study, the subjects chewed CMCTS-containing gum for 5 min and then rested for 5 min. When testing the CMCTS mouth rinse, the subjects gargled with 10 mL of solution for 30 s, followed by resting for 9rain 30 s. These protocols were repeated five times over a 50 min period on the same day. Post-experiment saliva samples were then collected at the following times： 0, 30 and 60 min. Results： Chewing gum containing CMCTS or rinsing with a CMCTS-containing rinse significantly decreased oral bacteria counts. The total bacteria counts, total Streptococci counts, and mutans streptococci counts of saliva from subjects who chewed CMCTS-containing gum were significantly lower than saliva from subjects in the rinse group in all three sampling periods, except in the case of the total bacteria count in the 60 min samples. Conclusion：CMCTS-containing gum chewing has a greater antibac- terial effect than using a CMCTS-containing mouth rinse. The present findings strongly indicate that the application of natural materials such as chitosan and its derivatives is useful for better oral health.
基金supported by the National Natural Science Foundation of China (Grant No. 81870800)the Science and Technology Department of Sichuan Province (Grant No. 2015JY0146)
文摘Inflammatory orofacial pain,in which substance P (SP) plays an important role,is closely related to the cross-talk between trigeminal ganglion (TG) neurons and satellite glial cells (SGCs).SGC activation is emerging as the key mechanism underlying inflammatory pain through different signalling mechanisms,including glial fibrillary acidic protein (GFAP) activation,phosphorylation of mitogen-activated protein kinase (MAPK) signalling pathways,and cytokine upregulation.However,in the TG,the mechanism underlying SP-mediated orofacial pain generated by SGCs is largely unknown.In this study,we investigated whether SP is involved in inflammatory orofacial pain by upregulating interleukin (IL)-1β and tumour necrosis factor (TNF)-α from SGCs,and we explored whether MAPK signalling pathways mediate the pain process.In the present study,complete Freund’s adjuvant (CFA) was injected into the whisker pad of rats to induce an inflammatory model in vivo.SP was administered to SGC cultures in vitro to confirm the effect of SP.Facial expression analysis showed that pre-injection of L703,606 (an NK-1 receptor antagonist),U0126 (an inhibitor of MAPK/extracellular signal-regulated kinase [ERK] kinase [MEK] 1/2),and SB203580 (an inhibitor of P38) into the TG to induce targeted prevention of the activation of the NK-1 receptor and the phosphorylation of MAPKs significantly suppressed CFA-induced inflammatory allodynia.In addition,SP promoted SGC activation,which was proven by increased GFAP,p-MAPKs,IL-1β and TNF-α in SGCs under inflammatory conditions.Moreover,the increase in IL-1β and TNF-α was suppressed by L703,606,U0126 and SB203580 in vivo and in vitro.These present findings suggested that SP,released from TG neurons,activated SGCs through the ERK1/2 and P38 pathways and promoted the production of IL-1β and TNF-α from SGCs,contributing to inflammatory orofacial pain associated with peripheral sensitization.
文摘BACKGROUND:Nerve invasion is a specific type of tumor expansion and characteristic manifestation of pancreatic cancer(PC),with an incidence rate ranging from 50% to 100%.It is an important prognostic factor for pancreatic cancer,and its early detection is helpful in the management of the disease.This study was undertaken to analyze retrospectively the relationship between neural invasion and multiple clinicopathological features and to provide evidences for clinicians in the management of neural invasion in patients with PC.METHODS:Formalin-fixed paraffin-embeded specimens of PC taken from 215 patients were examined for the presence of neural invasion under a light microscope.Analyzed was the relationship between neural invasion and multiple clinicopathological feature including preoperative fasting blood glucose level,amylase level,serum CA19-9 level,abdominal pain,lumbar and back pain,and the expressions of p53 and Ki67 in tumor tissues.RESULTS:Preoperative fasting blood glucose level,serum CA19-9 level and p53 positive cells in cancer tissue were increased with the rise of pathological grade(P【0.05).These indices were significantly higher in patients with neural invasion than in those without(P【0.05).Further analysis revealed a positive correlation between p53 and Ki67 overexpression and lymphatic metastasis(P【0.05).Referred pain was positively correlated with neural invasion(P【0.05).Patients with PC perineural invasion were more likely to have a higher pathological grade(P【0.05).CONCLUSIONS:Our data indicated that the preoperative fasting blood glucose level,serum CA19-9 level,and referred pain are novel predictive markers for neural invasion in patients with PC.p53 and Ki67 play important roles in neural invasion of PC.Management of hyperglycemia may serve as an auxiliary treatment to curb neural invasion in PC.
基金supported by the National Science Foundation of China (Grant No. 81000456)the Science and Technology Department of Sichuan Province (Grant No. 2009SZ0171)
文摘Chlorogenic acid（5-caffeoylquinic acid, CGA） is a phenolic compound that is found ubiquitously in plants, fruits and vegetables and is formed via the esterification of caffeic acid and quinic acid. In addition to its notable biological functions against cardiovascular diseases, type-2 diabetes and inflammatory conditions, CGA was recently hypothesized to be an alternative for the treatment of neurological diseases such as Alzheimer＇s disease and neuropathic pain disorders. However, its mechanism of action is unclear.Voltage-gated potassium channel（Kv） is a crucial factor in the electro-physiological processes of sensory neurons. Kv has also been identified as a potential therapeutic target for inflammation and neuropathic pain disorders. In this study, we analysed the effects of CGA on the two main subtypes of Kv in trigeminal ganglion neurons, namely, the IK,Aand IK,Vchannels. Trigeminal ganglion（TRG）neurons were acutely disassociated from the rat TRG, and two different doses of CGA（0.2 and 1 mmol·L21） were applied to the cells.Whole-cell patch-clamp recordings were performed to observe alterations in the activation and inactivation properties of the IK,Aand IK,Vchannels. The results demonstrated that 0.2 mmol·L21CGA decreased the peak current density of IK,A. Both 0.2 mmol·L21and1 mmol·L21CGA also caused a significant reduction in the activation and inactivation thresholds of IK,Aand IK,V. CGA exhibited a strong effect on the activation and inactivation velocities of IK,Aand IK,V. These findings provide novel evidence explaining the biological effects of CGA, especially regarding its neurological effects.
基金funded by the National Natural Science Foundation of China (Grant No. 81000456)the Science and Technology Department of Sichuan Province (Grant No. 2015JY0146)the Science and Technology Bureau of Chengdu (Grant No. 2014-HM01-00203-SF)
文摘The keeper and cast dowel-coping, as a primary component for a magnetic attachment, is easily subjected to corrosion in a wet environment, such as the oral cavity, which contains electrolyte-rich saliva, complex microflora and chewing behaviour and so on. The objective of this in vitro study was to examine the corrosion resistance of a dowel and coping-keeper complex fabricated by finish keeper and three alloys （cobalt-chromium, CoCr; silver-palladium-gold, PdAu; gold-platinum, AuPt） using a laser- welding process and a casting technique. The surface morphology characteristics and microstructures of the samples were examined by means of metallographic microscope and scanning electron microscope （SEM）. Energy-dispersive spectroscopy （EDS） with SEM provided elements analysis information for the test samples after 10% oxalic acid solution etching test. Tafel polarization curve recordings demonstrated parameter values indicating corrosion of the samples when subjected to electrochemical testing. This study has suggested that massive oxides are attached to the surface of the CoCr-keeper complex but not to the AuPt-keeper complex. Only the keeper area of cast CoCr-keeper complex displayed obvious intergranular corrosion and changes in the Fe and Co elements, Both cast and laser-welded AuPt-keeper complexes had the highest free corrosion potential, followed by the PdAu-keeper complex. We concluded that although the corrosion resistance of the CoCr-keeper complex was worst, the keeper surface passive film was actually preserved to its maximum extent. The laser-welded CoCr- and PdAu-keeper complexes possessed superior corrosion resistance as compared with their cast specimens, but no significant difference was found between the cast and laser-welded AuPt-keeper complexes. The Fe-poor and Cr-rich band, appearing on the edge of the keeper when casting, has been proven to be a corrosion-prone area.
文摘Objective: To evaluate the value of MSCT plain scan and enhanced CT in the diagnosis of thymic adenocarcinoma. Methods: From May 2013 to June 2018, 37 cases of MSCT plain scan and dual-phase enhanced scan of thymic adenocarcinoma were retrospectively analyzed. The location, shape, size, density (CT value), enhanced features, peripheral invasion and mediastinal lymph node metastasis of the lesions were observed. Results: All 37 cases of thymic adenocarcinoma were diagnosed by CT before operation, and all cases were diagnosed by pathology after operation as malignant tumors,including 28 cases of thoracic adenocarcinoma and 9 cases of invasive thymoma. All 28 cases of thymic adenocarcinoma were single lesion of anterior superior mediastinum. The maximum cross-section was located in the midline in 7 cases and on the mediastinal side in 21 cases with significant difference (P<0.05). All lesions were irregular lobulated. The minimum diameter of lesions was 2.1 cm and the maximum diameter was 8.6 cm. Soft tissue density was dominant in the solid part. All cases of thymic adenocarcinoma showed inhomogeneous, moderate and severe enhancement in the arterial and venous phase after enhancement. The degree of enhancement in the venous phase was higher than that in the arterial phase, and there was no enhancement in the irregular liquefied necrosis area. 26 cases had necrotic lesions, 21 cases had mediastinal lymph node metastasis, and 8 cases had invasion of adjacent pleura. 19 cases had mediastinal vessels and 0 cases had distant pleural metastases. Conclusion: MSCT plain scan combined with dual-phase enhanced CT is helpful to display the details and metastasis of thymic adenocarcinoma, improve the coincidence rate of CT diagnosis and pathological diagnosis, and reduce the misdiagnosis rate. To provide help for clinical diagnosis and treatment of thymic adenocarcinoma.
基金the National Natural Science Foundation of China(No.U1764258)the Taishan Scholar Project Foundation of Shandong Province(No.ts20190908)the Natural Science Foundation of Shandong Province(No.ZR2021ZD05).
文摘The application of light-weight current collectors is preferred because of the increased energy density of the batteries.Bearing it in mind,the cathode is designed with self-made paperlike memberane as current collector coupled with another interlayer to enable the high-energy-density lithium-sulfur batteries.Via a facile and green step-by-step methodology,the hybrid membrane is finalized successfully,consisting of reduced graphene oxide sheets covering paper-derived carbon(GPC)bearing Fe@Fe2O3 and Fe1−xS@Fe2O3 core-shell nanoparticles(FeFeO/FeSFeO@GPC).The film works as the current collector and interlayer simultaneously considering the porous and conductive features.As demonstrated by the electrochemical testing,the FeFeO/FeSFeO@GPC hybrid cell exhibits attractive cycling stability and superior rate capability.The cell configuration and structural/composition merits of FeFeO/FeSFeO@GPC film facilitate the faster reaction kinetics,conducive to the improvement of capacity retention.In view of the effective cathode design,the areal sulfur loading is increased to 10.46 mg·cm^(−2)and a reversible capacity of 6.67 mAh·cm^(−2)can be retained after 60 cycles at 0.1 C.
基金supported by grants from the National Foundation of Natural Science of China (31871049, 31771124, and 31800893)。
文摘Neuroinflammation and a-synuclein (a-syn) aggregation are both neuropathological hallmarks of Parkinson’s disease (PD). Microglia are crucial participants in eliciting neuroinflammatory responses themselves, as well as modulating neurotoxic activity in astrocytes, therefore forming a pathway to neurodegeneration induced by both central and peripheral insults [1, 2].
基金supported by the National Natural Science Foundation of China(31871049 and 32170984).
文摘Misfoldedα-synuclein(α-syn)hallmarks the neuropathological characteristics of Parkinson's disease(PD)and acts as a"pathological seed"that promotes the progression of the disease[1].About 15%of PD patients have a family history,5%-10%have a monogenic disorder with a Mendelian pattern of inheritance[2],and>90 independent risk signals identified by genome-wide association studies(GWASs)can be used to explain the non-monogenic risk of PD[3].
基金supported by the National Natural Science Foundation of China(grant nos.U21A2077 and 21871164)the Taishan Scholar Project Foundation of Shandong Province(grant no.ts20190908)the Natural Science Foundation of Shandong Province(grant nos.ZR2021ZD05 and ZR2019MB024).
文摘The use of transition-metal phosphides(TMPs)as catalytic materials to accelerate kinetics of lithium polysulfide(LiPS)conversion has unique advantages.Nevertheless,simple and low-cost preparation strategies are still required for the synthesis of novel TMPs with satisfactory performance.Importantly,the in-depth understanding of the effect of intrinsic interaction between catalytic materials and LiPSs on the promoted kinetics remains limited.Herein,a novel structure of tungsten phosphide(WP)nanocrystals decorated on N,P codoped carbon sheets(WP/NPC)with uniform dispersion is designed by a structure-oriented strategy to promote LiPS redox kinetics.The electrochemical kinetics measurements coupled with density functional theory computations and in situ/ex situ characterizations demonstrate that the strong interaction through W–S bonding and the favorable interfacial charge state of WP-LiPSs promote the nucleation and dissociation of Li2S.Benefiting from this superiority,the WP/NPG-based lithium–sulfur batteries indicate significantly improved electrochemical performance with good cycling life and excellent rate capability.This work provides a methodology for the design of TMP-involved electrode materials and a fundamental understanding of the intrinsic mechanism of catalysis.
基金supported by the grants from the National Natural Science Foundation of China(Nos.31225020,31421005,and 91435206)grant from the National High Technology Research and Development of China(No.2012AA10A305)2011-G15 from the‘948’project
文摘CRISPR/Cas （clustered regularly interspaced short palindromic repeats/CR1SPR-associated proteins） is an adaptive immune system in bacteria and archaea to defend against invasion from foreign DNA fragments. Recently, it has been developed as a powerful targeted genome editing tool for a wide variety of species. However, its application in maize has only been tested with transiently expressed somatic cells or with a limited number of stable transgenic To plants. The exact efficiency and specificity of the CRISPR/Cas system in the highly complex maize genome has not been documented yet. Here we report an extensive study of the well-studied type II CRISPR-Cas9 system for targeted genome editing in maize, with the codon-optimized Cas9 protein and the short non-coding guide RNA generated through a functional maize U6 snRNA promoter. Targeted gene mutagenesis was detected for 90 loci by maize protoplast assay, with an average cleavage efficiency of 10.67 %. Stable knockout transformants for maize phytoene synthase gene （PSYI） were obtained. Mutations occurred in germ ceils can be stably inherited to the next generation. Moreover, no off-target effect was detected at the computationally predicted putative off-target loci. No significant difference between the transcriptomes of the Cas9 expressed and non-expressed lines was detected. Our results confirmed that the CRISPR-Cas9 could be successfully applied as a robust targeted genome editing system in maize.
基金supported by grants from the National Natural Science Foundation of China(81430024,31771124,31571054,and 31371081)Excellent Innovative Team of Shandong Province and Taishan Scholars Construction Project
文摘Parkinson’s disease(PD)is recognized as the second most common neurodegenerative disorder after Alzheimer disease.Although a fascinating 200-year journey of research has revealed the multifaceted nature of PD[1,2],its fundamental features are the loss of dopaminergic neurons in the substantia nigra pars compacta(SNpc)and depletion of dopamine(DA)in the striatum.Iron accumulates in normal brains with aging.Such
文摘Eukaryotic initiation factor subunit c(eIF3c) has been identified as an oncogene that is over-expressed in tumor cells and,therefore,is a potential therapeutic target for gene-based cancer treatment.This study was focused on investigating the effect of small interfering RNA(siRNA)-mediated eIF3c gene knockdown on colon cancer cell survival.The eIF3c gene was observed to be highly expressed in colon cancer cell models.The expression levels of the gene in eIF3c siRNA infected and control siRNA infected cells were compared via real-time polymerase chain reaction(PCR) and western blotting analysis.Cell proliferation levels were analyzed employing 3-(4,5-dimethylthiazol 2-yl)-2,5-diphenyltetrazolium bromide(MTT) and colony formation assays.Furthermore,the effects of eIF3c gene knockdown on the cell cycle and apoptosis were analyzed using flow cytometry.The results showed that suppression of eIF3c expression significantly(P<0.001) reduced cell proliferation and colony formation of RKO colon cancer cells.The cell cycle was arrested by decreasing the number of cells entering S phase.Further,apoptosis was induced as a result of eIF3c knockdown.Collectively,eIF3c deletion effectively reduced the survival of colon cancer cells and could be used as a therapeutic tool for colon cancer therapy.
