It aims to investigate the protective effects of sodium hyaluronate,panthenol,Portulaca oleracea L.and Calendula officinalis L.on hyperosmotic dehydration-induced injury of human immortalized keratinocytes(HaCaT).The ...It aims to investigate the protective effects of sodium hyaluronate,panthenol,Portulaca oleracea L.and Calendula officinalis L.on hyperosmotic dehydration-induced injury of human immortalized keratinocytes(HaCaT).The safety mass concentrations of four raw materials were screened by detecting cell viability,and the secretion of hyaluronic acid(HA)was determined using the ELISA method.The expression of HaCaT barrier function related genes(OVOL1,EREG,TGM1,TGM2,IVL,IRF6,THBS1,CASP14)was detected at the mRNA level to explore the regulatory effect of four raw materials on these genes.The results demonstrate that pretreatment with the four kinds of raw materials could increase the cell viability after hyperosmotic dehydration,promote the secretion of HA,and improve the expression of barrier function related genes after hyperosmotic dehydration,among which panthenol and Calendula officinalis L.are better.The results show that the four raw materials have a certain protective effect on the hyperosmotic dehydration cell model,which provides data support for its application in cosmetics.展开更多
A new principle for grounding fault feeder detection based on negative sequence current variation and energy dissipated in the fault point is presented. It has high precision in both isolated systems and resonance ear...A new principle for grounding fault feeder detection based on negative sequence current variation and energy dissipated in the fault point is presented. It has high precision in both isolated systems and resonance earthed systems, even in full compensated systems. And it can be installed at the local control unit of feeder in distribution automation systems, such as field terminal unit (FTU). This principle is verified by EMTP simulator and experimentation.展开更多
AIM: To evaluate the effects of combined treatment of glutamine (Gln) and recombinant human growth hormone(rhGH) on intestinal barrier function following portal hypertension surgery. METHODS: This study was desi...AIM: To evaluate the effects of combined treatment of glutamine (Gln) and recombinant human growth hormone(rhGH) on intestinal barrier function following portal hypertension surgery. METHODS: This study was designed as a prospective, randomized and controlled clinical trial. Forty two patients after portal hypertension surgery were randomly assigned into 2 groups: control group (n = 20) and supplemental group (adding Gin and rhGH, n = 22). Every patient received isocaloric and isonitrogenous standard total parenteral nutrition (TPN) starting 3 d after surgery for 7 d. Blood samples were obtained before surgery and at the 3rd and 10th day postoperatively. Host immunity was evaluated by measuring levels of CD4, CD8, CD4/CD8, IgG, IgM and IgA, and the inflammatory responses were determined by assessing IL-2, TNF-α and C-reactive protein (CRP) levels. Intestinal permeability and integrity was evaluated by L/M test and histological examination, respectively. RESULTS: On postoperative d 10, CD4, CD4/CD8, IgG and IL-2 levels in supplemental group were significantly higher than those in control group (33.7±5.5 vs 31.0 ± 5.4, P 〈 0.05, (1.17±0.32 vs 1.05 ± 0.15, P 〈 0.05, 13.94±1.09 vs 12.33±1.33, P 〈 0.05, and 368.12 ± 59.25 vs 318.12 ± 45.65, P 〈 0.05, respectively), whereas the increase in serum TNF-α concentration was significantly reduced (41.02 ± 27.56 vs 160.09 ± 35.17, P 〈 0.05). The increase in L/M ratio was significantly lower in the supplemental group than in the control group (0.0166 ± 0.0017 vs 0.0339 ± 0.0028, P 〈 0.05). Moreover, mucosal integrity in the supplemental group was better than in the control group.CONCLUSION: Postoperative administration of TPN supplemented with Gin and rhGH in patients after portal hypertension surgery improves immune function, modulates inflammatory response, prevents the intestinal mucous membrane from atrophy and preserves intestinal integrity.展开更多
The active-fault-alarm (AFA) technologies and the dynamic protection mechanism of the optical network controlled by the multi-protocol label switching transport profile (MPLS-TP) are both studied in this article. ...The active-fault-alarm (AFA) technologies and the dynamic protection mechanism of the optical network controlled by the multi-protocol label switching transport profile (MPLS-TP) are both studied in this article. On this basis, an active dynamic pre-protection (ADPP) mechanism is proposed. This active dynamic pre-protection mechanism is allowed to establish a so called temporary protection path (TPP) for the work path before a potential fault occurs and to switch to TPP only after the fault occurs. It keeps the TPP flexibly only when it is in low- quality or fault state to realize dynamic protection even better and to achieve better resource utilization. Simulation results show that the proposed new mechanism has better performance in terms of the flexibility and the efficiency from the perspective of time.展开更多
In a multi-hop wireless mesh network, wireless links are vulnerable due to severe channel fading, interference and physical damage. In this paper, we will provide a coding scheme to protect from multiple failures in w...In a multi-hop wireless mesh network, wireless links are vulnerable due to severe channel fading, interference and physical damage. In this paper, we will provide a coding scheme to protect from multiple failures in wireless mesh networks to achieve high throughput where the redundancy is considered for the average number of failures. Our coding scheme is designed to protect from the average number of failures to increase the network throughput. When the number of failures is more than the average case, the destination will have to wait for more coded packets in the following time slots.展开更多
This technical paper presents the resolution of high leakage current failures on QFN-mr (Quad-Flat No-leads Multi-Row) LF (leadframe) devices by optimizing the waterjet deflash process and eliminating the ESD (el...This technical paper presents the resolution of high leakage current failures on QFN-mr (Quad-Flat No-leads Multi-Row) LF (leadframe) devices by optimizing the waterjet deflash process and eliminating the ESD (electrostatic discharge) events. ESD damage to units can cause permanent or latent product failures which results in low final test yield, and worse, possible external customer complaints. The use of CO2 (carbon dioxide) bubbler was able to reduce the DI (deionized) water’s equivalent resistivity from 17 M? to 0.30 M?, minimizing the tribocharging effect produced during the waterjet deflash process. Moreover, ESD events were eliminated by grounding the floating assembly equipment parts and installing appropriate ESD controls. It is of high importance to reduce or eliminate the leakage current failures to ensure the product quality, especially as the market becomes more demanding. After the optimization and implementation of the corrective and improvement actions, high leakage current occurrence was significantly reduced from baseline of 5,784 ppm to 20 ppm.展开更多
The "new normal" is the current stage of development of China's economy. The "new" in new normal means different to past; the "normal" means relatively stable. For a period of time in the future, the decrease o...The "new normal" is the current stage of development of China's economy. The "new" in new normal means different to past; the "normal" means relatively stable. For a period of time in the future, the decrease of potential growth rate has become an indisputable fact. Social security fund is an important source of funds for the protection of people's livelihood, whose every movement often attract much attention. Under the situation of new normal economy, how to ensure the preserving or increasing value of social security funds on the premise of security is the core task in the operations management of social security fund investment. At present, there are some difficulties in the development of the social security funds, such as the management system and operation mechanism are not perfect, some institutional measures have not been fully implemented and the progress of the law and regulations is slow. In this paper, we will put forward some corresponding improvement measures, such as expand the scope of social security fund investment, accelerate the implementation of the nominal account system and strengthen the actuarial management of social security fund.展开更多
This paper presents an ANN (artificial neural networks)-based technique for improving the performance of distance relays against open-circuit faults in transmission networks. The technique utilizes the small capacit...This paper presents an ANN (artificial neural networks)-based technique for improving the performance of distance relays against open-circuit faults in transmission networks. The technique utilizes the small capacitive current measured in the open-phase plus the currents in the two healthy phases in calculating the open-circuit fault distance. The results obtained show that a distance relay with the proposed scheme will not only be able to detect the open-conductor condition in HVTL (high voltage transmission line) but also to locate the place of this fault regardless the value of the pre-fault current loading. There is no need for especial communication schemes since the existing media could work properly for the needs of the proposed technique.展开更多
The protection of distribution networks is facing new challenges from an increasing amount of DG (distributed generation). Even though current technology provides satisfactory solutions to manage this new situation,...The protection of distribution networks is facing new challenges from an increasing amount of DG (distributed generation). Even though current technology provides satisfactory solutions to manage this new situation, LOM (loss-of-mains protection) is still considered problematic. The solution proposed in this paper focuses on the use of a line differential protection relay. It inherently contains a suitable communication channel and provides absolutely selective protection for the feeder. Furthermore, it prevents the feeder relays from false tripping for faults on the neighboring feeder. The present trend in protection communication points towards the use of fiber optics. For line differential protection, this means a fast and high-capacity communication link which enables the implementation of many advanced protection functions. In addition, a solid foundation for such a communication link is offered by the new IEC 61850 standard and Ethernet technologies. The basic functionality of the line differential protection enables the operation of both the feeder protection and the DG protection for any fault on the feeder. Furthermore, basic LOM protection methods can be applied as backup protection for failures on the communication link.展开更多
A deregulated power market is making short-circuit currents likely to exceed the thermal or mechanical permissible limits of switchgear. Consequently fault current limiters (FCL) become more necessary in power syste...A deregulated power market is making short-circuit currents likely to exceed the thermal or mechanical permissible limits of switchgear. Consequently fault current limiters (FCL) become more necessary in power systems. The use of FCLs has an impact on the protection schemes and functions in power systems. Thus, before FCLs can be applied in the network, the impacts on existing protection system must be understood. Depending on the current limiting technique used, today's protection concepts may have to be adapted or revised to ensure proper network protection selectivity. A relationship between fault current limiters and protection schemes should be established by taking into account both protection and network specific issues, such as the impact of different FCL technologies, existing and new protection concepts, selectivity and innovative network. This paper is presenting a frame work for accomplishing this task.展开更多
OBJECTIVE: To investigate the effect of the periplaneta americana extract on the intestinal mucosal barrier and prognostic implications in patients with sepsis. METHODS: Sixty and six patients with sepsis were assig...OBJECTIVE: To investigate the effect of the periplaneta americana extract on the intestinal mucosal barrier and prognostic implications in patients with sepsis. METHODS: Sixty and six patients with sepsis were assigned randomly to treatment group (32 cases) and control group (32 cases). The extractfrom periplaneta americana plus conventional medication for sepsis was administered to the treatment group, while the control group only received conventional treatment. The gastrointestinal function scores and acute physiology and chronic health evaluation II (APACHE 11 ) scores of all subjects were documented at baseline, at days 1, 3 and 7 after treatment respectively and their blood endotoxin was tested at the same time points as well. The incidence of death was recorded for both groups throughout the trial. RESULTS: At days 3 and 7 after treatment, gastrointestinal function score, APACHE II, and endotoxin level in treatment group wasbetter than that in con- trol group and the difference between them was significant (both P〈0~05). Although the incidence of death in treatment group was less than that in control group, the difference between the two groups was not significant (P〉 0.05). CONCLUSION: The extract of periplaneta ameri- cana had protective effect on intestinal mucosal barrier and could improve the condition and prog- nosis in patients with sepsis.展开更多
The advent of total mesorectal excision(TME)together with minimally invasive techniques such as laparoscopic colorectal surgery and robotic surgery has improved surgical results.However,the incidence of bladder and se...The advent of total mesorectal excision(TME)together with minimally invasive techniques such as laparoscopic colorectal surgery and robotic surgery has improved surgical results.However,the incidence of bladder and sexual dysfunction remains high.This may be particularly distressing for the patient and troublesome to manage for the surgeon when it does occur.The increased use of neoadjuvant and adjuvant radiotherapy is also associated with poorer functional outcomes.In this review,we evaluate current understanding of the anatomy of pelvic nerves which are divided into the areas of the inferior mesenteric artery pedicle,the lateral pelvic wall and dissection around the urogenital organs.Surgical techniques in these areas are discussed.We also discuss the results in functional outcomes of the various techniques including open,laparoscopic and robotic over the last 30 years.展开更多
4-Acylated or 3,4-diacylated caffeic acid phenethyl ester (CAPE) was prepared as prodrug to improve its stability and lipid solubility. Their neuroprotective activities were assessed by H202 model and 6-OHDA model. ...4-Acylated or 3,4-diacylated caffeic acid phenethyl ester (CAPE) was prepared as prodrug to improve its stability and lipid solubility. Their neuroprotective activities were assessed by H202 model and 6-OHDA model. The results showed that target compounds displayed positive abilities to protect PC 12 nerve cells from oxidative stress injury, superior to that of CAPE. Additionally, target compounds showed high blood-brain barrier permeability.展开更多
The molecular mechanisms that regulate synapse formation have been well documented. However, little is known about the factors that modulate synaptic stability. Synapse loss is an early and invariant feature of neurod...The molecular mechanisms that regulate synapse formation have been well documented. However, little is known about the factors that modulate synaptic stability. Synapse loss is an early and invariant feature of neurodegenerative diseases including Alzheimer's lAD) and Parkinson's disease. Notably, in AD the extent of synapse loss correlates with the severity of the disease. Hence, understanding the molecular mechanisms that underlie synaptic maintenance is crucial to reveal potential targets that will allow the development of ther- apies to protect synapses. Writs play a central role in the formation and function of neuronal circuits. Moreover, Wnt signaling compo- nents are expressed in the adult brain suggesting their role in synaptic maintenance in the adult. Indeed, blockade of Wnts with the Wnt antagonist Dickkopf-1 (Dkkl) causes synapse disassembly in mature hippocampal cells. Dkkl is elevated in brain biopsies from AD patients and animal models. Consistent with these findings, Amyloid-β (Aβ) oUgomers induce the rapid expression of Dkkl. Importantly, Dkkl neutralizing antibodies protect synapses against Aβ toxicity, indicating that Dkkl is required for Aβ-mediated synapse loss. In this review, we discuss the role of Wnt signaling in synapse maintenance in the adult brain, particularly in relation to synaptic loss in neurodegenerative diseases.展开更多
文摘It aims to investigate the protective effects of sodium hyaluronate,panthenol,Portulaca oleracea L.and Calendula officinalis L.on hyperosmotic dehydration-induced injury of human immortalized keratinocytes(HaCaT).The safety mass concentrations of four raw materials were screened by detecting cell viability,and the secretion of hyaluronic acid(HA)was determined using the ELISA method.The expression of HaCaT barrier function related genes(OVOL1,EREG,TGM1,TGM2,IVL,IRF6,THBS1,CASP14)was detected at the mRNA level to explore the regulatory effect of four raw materials on these genes.The results demonstrate that pretreatment with the four kinds of raw materials could increase the cell viability after hyperosmotic dehydration,promote the secretion of HA,and improve the expression of barrier function related genes after hyperosmotic dehydration,among which panthenol and Calendula officinalis L.are better.The results show that the four raw materials have a certain protective effect on the hyperosmotic dehydration cell model,which provides data support for its application in cosmetics.
文摘A new principle for grounding fault feeder detection based on negative sequence current variation and energy dissipated in the fault point is presented. It has high precision in both isolated systems and resonance earthed systems, even in full compensated systems. And it can be installed at the local control unit of feeder in distribution automation systems, such as field terminal unit (FTU). This principle is verified by EMTP simulator and experimentation.
文摘AIM: To evaluate the effects of combined treatment of glutamine (Gln) and recombinant human growth hormone(rhGH) on intestinal barrier function following portal hypertension surgery. METHODS: This study was designed as a prospective, randomized and controlled clinical trial. Forty two patients after portal hypertension surgery were randomly assigned into 2 groups: control group (n = 20) and supplemental group (adding Gin and rhGH, n = 22). Every patient received isocaloric and isonitrogenous standard total parenteral nutrition (TPN) starting 3 d after surgery for 7 d. Blood samples were obtained before surgery and at the 3rd and 10th day postoperatively. Host immunity was evaluated by measuring levels of CD4, CD8, CD4/CD8, IgG, IgM and IgA, and the inflammatory responses were determined by assessing IL-2, TNF-α and C-reactive protein (CRP) levels. Intestinal permeability and integrity was evaluated by L/M test and histological examination, respectively. RESULTS: On postoperative d 10, CD4, CD4/CD8, IgG and IL-2 levels in supplemental group were significantly higher than those in control group (33.7±5.5 vs 31.0 ± 5.4, P 〈 0.05, (1.17±0.32 vs 1.05 ± 0.15, P 〈 0.05, 13.94±1.09 vs 12.33±1.33, P 〈 0.05, and 368.12 ± 59.25 vs 318.12 ± 45.65, P 〈 0.05, respectively), whereas the increase in serum TNF-α concentration was significantly reduced (41.02 ± 27.56 vs 160.09 ± 35.17, P 〈 0.05). The increase in L/M ratio was significantly lower in the supplemental group than in the control group (0.0166 ± 0.0017 vs 0.0339 ± 0.0028, P 〈 0.05). Moreover, mucosal integrity in the supplemental group was better than in the control group.CONCLUSION: Postoperative administration of TPN supplemented with Gin and rhGH in patients after portal hypertension surgery improves immune function, modulates inflammatory response, prevents the intestinal mucous membrane from atrophy and preserves intestinal integrity.
基金Supported by the National High Technology Research and Development Program of China(No. 2009AA01Z255, 2009AA01A345), the National Basic Research Program of China(No. 2007CB310705 ) and the National Natural Science Foundation of China(No. 60932004).
文摘The active-fault-alarm (AFA) technologies and the dynamic protection mechanism of the optical network controlled by the multi-protocol label switching transport profile (MPLS-TP) are both studied in this article. On this basis, an active dynamic pre-protection (ADPP) mechanism is proposed. This active dynamic pre-protection mechanism is allowed to establish a so called temporary protection path (TPP) for the work path before a potential fault occurs and to switch to TPP only after the fault occurs. It keeps the TPP flexibly only when it is in low- quality or fault state to realize dynamic protection even better and to achieve better resource utilization. Simulation results show that the proposed new mechanism has better performance in terms of the flexibility and the efficiency from the perspective of time.
文摘In a multi-hop wireless mesh network, wireless links are vulnerable due to severe channel fading, interference and physical damage. In this paper, we will provide a coding scheme to protect from multiple failures in wireless mesh networks to achieve high throughput where the redundancy is considered for the average number of failures. Our coding scheme is designed to protect from the average number of failures to increase the network throughput. When the number of failures is more than the average case, the destination will have to wait for more coded packets in the following time slots.
文摘This technical paper presents the resolution of high leakage current failures on QFN-mr (Quad-Flat No-leads Multi-Row) LF (leadframe) devices by optimizing the waterjet deflash process and eliminating the ESD (electrostatic discharge) events. ESD damage to units can cause permanent or latent product failures which results in low final test yield, and worse, possible external customer complaints. The use of CO2 (carbon dioxide) bubbler was able to reduce the DI (deionized) water’s equivalent resistivity from 17 M? to 0.30 M?, minimizing the tribocharging effect produced during the waterjet deflash process. Moreover, ESD events were eliminated by grounding the floating assembly equipment parts and installing appropriate ESD controls. It is of high importance to reduce or eliminate the leakage current failures to ensure the product quality, especially as the market becomes more demanding. After the optimization and implementation of the corrective and improvement actions, high leakage current occurrence was significantly reduced from baseline of 5,784 ppm to 20 ppm.
文摘The "new normal" is the current stage of development of China's economy. The "new" in new normal means different to past; the "normal" means relatively stable. For a period of time in the future, the decrease of potential growth rate has become an indisputable fact. Social security fund is an important source of funds for the protection of people's livelihood, whose every movement often attract much attention. Under the situation of new normal economy, how to ensure the preserving or increasing value of social security funds on the premise of security is the core task in the operations management of social security fund investment. At present, there are some difficulties in the development of the social security funds, such as the management system and operation mechanism are not perfect, some institutional measures have not been fully implemented and the progress of the law and regulations is slow. In this paper, we will put forward some corresponding improvement measures, such as expand the scope of social security fund investment, accelerate the implementation of the nominal account system and strengthen the actuarial management of social security fund.
文摘This paper presents an ANN (artificial neural networks)-based technique for improving the performance of distance relays against open-circuit faults in transmission networks. The technique utilizes the small capacitive current measured in the open-phase plus the currents in the two healthy phases in calculating the open-circuit fault distance. The results obtained show that a distance relay with the proposed scheme will not only be able to detect the open-conductor condition in HVTL (high voltage transmission line) but also to locate the place of this fault regardless the value of the pre-fault current loading. There is no need for especial communication schemes since the existing media could work properly for the needs of the proposed technique.
文摘The protection of distribution networks is facing new challenges from an increasing amount of DG (distributed generation). Even though current technology provides satisfactory solutions to manage this new situation, LOM (loss-of-mains protection) is still considered problematic. The solution proposed in this paper focuses on the use of a line differential protection relay. It inherently contains a suitable communication channel and provides absolutely selective protection for the feeder. Furthermore, it prevents the feeder relays from false tripping for faults on the neighboring feeder. The present trend in protection communication points towards the use of fiber optics. For line differential protection, this means a fast and high-capacity communication link which enables the implementation of many advanced protection functions. In addition, a solid foundation for such a communication link is offered by the new IEC 61850 standard and Ethernet technologies. The basic functionality of the line differential protection enables the operation of both the feeder protection and the DG protection for any fault on the feeder. Furthermore, basic LOM protection methods can be applied as backup protection for failures on the communication link.
文摘A deregulated power market is making short-circuit currents likely to exceed the thermal or mechanical permissible limits of switchgear. Consequently fault current limiters (FCL) become more necessary in power systems. The use of FCLs has an impact on the protection schemes and functions in power systems. Thus, before FCLs can be applied in the network, the impacts on existing protection system must be understood. Depending on the current limiting technique used, today's protection concepts may have to be adapted or revised to ensure proper network protection selectivity. A relationship between fault current limiters and protection schemes should be established by taking into account both protection and network specific issues, such as the impact of different FCL technologies, existing and new protection concepts, selectivity and innovative network. This paper is presenting a frame work for accomplishing this task.
文摘OBJECTIVE: To investigate the effect of the periplaneta americana extract on the intestinal mucosal barrier and prognostic implications in patients with sepsis. METHODS: Sixty and six patients with sepsis were assigned randomly to treatment group (32 cases) and control group (32 cases). The extractfrom periplaneta americana plus conventional medication for sepsis was administered to the treatment group, while the control group only received conventional treatment. The gastrointestinal function scores and acute physiology and chronic health evaluation II (APACHE 11 ) scores of all subjects were documented at baseline, at days 1, 3 and 7 after treatment respectively and their blood endotoxin was tested at the same time points as well. The incidence of death was recorded for both groups throughout the trial. RESULTS: At days 3 and 7 after treatment, gastrointestinal function score, APACHE II, and endotoxin level in treatment group wasbetter than that in con- trol group and the difference between them was significant (both P〈0~05). Although the incidence of death in treatment group was less than that in control group, the difference between the two groups was not significant (P〉 0.05). CONCLUSION: The extract of periplaneta ameri- cana had protective effect on intestinal mucosal barrier and could improve the condition and prog- nosis in patients with sepsis.
文摘The advent of total mesorectal excision(TME)together with minimally invasive techniques such as laparoscopic colorectal surgery and robotic surgery has improved surgical results.However,the incidence of bladder and sexual dysfunction remains high.This may be particularly distressing for the patient and troublesome to manage for the surgeon when it does occur.The increased use of neoadjuvant and adjuvant radiotherapy is also associated with poorer functional outcomes.In this review,we evaluate current understanding of the anatomy of pelvic nerves which are divided into the areas of the inferior mesenteric artery pedicle,the lateral pelvic wall and dissection around the urogenital organs.Surgical techniques in these areas are discussed.We also discuss the results in functional outcomes of the various techniques including open,laparoscopic and robotic over the last 30 years.
基金National Natural Science Foundation of China(Grant No.201310061931.8)
文摘4-Acylated or 3,4-diacylated caffeic acid phenethyl ester (CAPE) was prepared as prodrug to improve its stability and lipid solubility. Their neuroprotective activities were assessed by H202 model and 6-OHDA model. The results showed that target compounds displayed positive abilities to protect PC 12 nerve cells from oxidative stress injury, superior to that of CAPE. Additionally, target compounds showed high blood-brain barrier permeability.
文摘The molecular mechanisms that regulate synapse formation have been well documented. However, little is known about the factors that modulate synaptic stability. Synapse loss is an early and invariant feature of neurodegenerative diseases including Alzheimer's lAD) and Parkinson's disease. Notably, in AD the extent of synapse loss correlates with the severity of the disease. Hence, understanding the molecular mechanisms that underlie synaptic maintenance is crucial to reveal potential targets that will allow the development of ther- apies to protect synapses. Writs play a central role in the formation and function of neuronal circuits. Moreover, Wnt signaling compo- nents are expressed in the adult brain suggesting their role in synaptic maintenance in the adult. Indeed, blockade of Wnts with the Wnt antagonist Dickkopf-1 (Dkkl) causes synapse disassembly in mature hippocampal cells. Dkkl is elevated in brain biopsies from AD patients and animal models. Consistent with these findings, Amyloid-β (Aβ) oUgomers induce the rapid expression of Dkkl. Importantly, Dkkl neutralizing antibodies protect synapses against Aβ toxicity, indicating that Dkkl is required for Aβ-mediated synapse loss. In this review, we discuss the role of Wnt signaling in synapse maintenance in the adult brain, particularly in relation to synaptic loss in neurodegenerative diseases.