Pharmacological properties of TRPM3 isoforms are determined by the length of the pore loop

BACKGROUND AND PURPOSE

Transient receptor potential melastatin 3 (TRPM3) is a non-selective cation channel that plays a pivotal role in the peripheral nervous system as a transducer of painful heat signals. Alternative splicing gives rise to several TRPM3 variants. The functional consequences of these splice isoforms are poorly understood. Here, the pharmacological properties of TRPM3 variants arising from alternative splicing in the pore-forming region were compared.

EXPERIMENTAL APPROACH

Calcium microfluorimetry and patch clamp recordings were used to compare the properties of heterologously expressed TRPM3α1 (long pore variant) and TRPM3α2-α6 (short pore variants). Furthermore, site-directed mutagenesis was done to investigate the influence of the length of the pore loop on the channel function.

KEY RESULTS

All short pore loop TRPM3α variants (TRPM3α2-α6) were activated by the neurosteroid pregnenolone sulphate (PS) and by nifedipine, whereas the long pore loop variant TRPM3α1 was insensitive to either compound. In contrast, TRPM3α1 was robustly activated by clotrimazole, a compound that does not directly activate the short pore variants but potentiates their responses to PS. Clotrimazole-activated TRPM3α1 currents were largely insensitive to established TRPM3α2 antagonists and were only partially inhibited upon activation of the μ opioid receptor. Finally, by creating a set of mutant channels with pore loops of intermediate length, we showed that the length of the pore loop dictates differential channel activation by PS and clotrimazole.

CONCLUSION AND IMPLICATIONS

Alternative splicing in the pore-forming region of TRPM3 defines the channel's pharmacological properties, which depend critically on the length of the pore-forming loop.

Ketamine and its metabolite, (2R,6R)-HNK, restore hippocampal LTP and long-term spatial memory in the Wistar-Kyoto rat model of depression

Accumulating evidence implicates dysregulation of hippocampal synaptic plasticity in the pathophysiology of depression. However, the effects of ketamine on synaptic plasticity and their contribution to its mechanism of action as an antidepressant, are still unclear. We investigated ketamine’s effects on in vivo dorsal hippocampal (dHPC) synaptic plasticity and their role in mediating aspects of antidepressant activity in the Wistar-Kyoto (WKY) model of depression. dHPC long-term potentiation (LTP) was significantly impaired in WKY rats compared to Wistar controls. Importantly, a single low dose (5 mg/kg, ip) of ketamine or its metabolite, (2R,6R)-HNK, rescued the LTP deficit in WKY rats at 3.5 h but not 30 min following injection, with residual effects at 24 h, indicating a delayed, sustained facilitatory effect on dHPC synaptic plasticity. Consistent with the observed dHPC LTP deficit, WKY rats exhibited impaired hippocampal-dependent long-term spatial memory as measured by the novel object location recognition test (NOLRT), which was effectively restored by pre-treatment with both ketamine or (2R,6R)-HNK. In contrast, in WKYs, which display abnormal stress coping, ketamine, but not (2R,6R)-HNK, had rapid and sustained effects in the forced swim test (FST), a commonly used preclinical screen for antidepressant-like activity. The differential effects of (2R,6R)-HNK observed here reveal a dissociation between drug effects on FST immobility and dHPC synaptic plasticity. Therefore, in the WKY rat model, restoring dHPC LTP was not correlated with ketamine’s effects in FST, but importantly, may have contributed to the reversal of hippocampal-dependent cognitive deficits, which are critical features of clinical depression. Our findings support the theory that ketamine may reverse the stress-induced loss of connectivity in key neural circuits by engaging synaptic plasticity processes to “reset the system”.

Molecular interactions between monoclonal oligomer-specific antibody 5E3 and its amyloid beta cognates

Oligomeric amyloid β (Aβ) is currently considered the most neurotoxic form of the Aβ peptide implicated in Alzheimer’s disease (AD). The molecular structures of the oligomers have remained mostly unknown due to their transient nature. As a result, the molecular mechanisms of interactions between conformation-specific antibodies and their Aβ oligomer (AβO) cognates are not well understood. A monoclonal conformation-specific antibody, m5E3, was raised against a structural epitope of Aβ oligomers. m5E3 binds to AβOs with high affinity, but not to Aβ monomers or fibrils. In this study, a computational model of the variable fragment (Fv) of the m5E3 antibody (Fv5E3) is introduced. We further employ docking and molecular dynamics simulations to determine the molecular details of the antibody-oligomer interactions, and to classify the AβOs as Fv5E3-positives and negatives, and to provide a rationale for the low affinity of Fv5E3 for fibrils. This information will help us to perform site-directed mutagenesis on the m5E3 antibody to improve its specificity and affinity toward oligomeric Aβ species. We also provide evidence for the possible capability of the m5E3 antibody to disaggregate AβOs and to fragment protofilaments.

[Value of absolute quantification of myocardial perfusion by PET in detecting coronary microvascular disease in patients with non-obstructive coronaries]

Objective: To compare the incidence of coronary microvascular disease (CMVD) between patients with non-obstructive and obstructive coronary arteries. Methods: We retrospectively analyzed 97 patients with angina pectoris, who underwent the absolute quantitative PET examination of myocardial perfusion and coronary anatomy examination within 90 days. All patients were divided into two groups: non-obstructive group (72 cases, no stenosis ≥50% in all three coronary arteries) and obstructive group (25 cases, at least one coronary stenosis ≥50%; and at least one coronary stenosis<50%). Quantitative parameters derived from PET including rest myocardial blood flow (RMBF), stress myocardial blood flow (SMBF), coronary flow reserve (CFR) and cardiovascular risk factors were compared between the two groups. CMVD was defined as CFR<2.90 and SMBF<2.17 ml·min(-1)·g(-1). Results: Incidence of CMVD was significant higher in the non-obstructive coronary arteries of the obstructive group than in the non-obstructive coronary arteries of non-obstructive group (47.1% (16/34) vs. 25.5% (55/216), χ(2)=6.738, P=0.009) while incidence of CMVD was similar between non-obstructive and obstructive patients ((44% (11/25) vs. 33.3% (24/72), χ(2)=0.915, P=0.339). RMBF ((0.83±0.14) ml·min(-1)·g(-1) vs. (0.82±0.17) ml·min(-1)·g(-1)), SMBF ((2.13±0.60) ml·min(-1)·g(-1) vs. (1.91±0.50) ml·min(-1)·g(-1)) and CFR (2.59±0.66 vs. 2.36±0.47) were similar between the two groups (all P>0.05). Conclusions: CMVD can occur in non-obstructive coronary arteries in both patients with non-occlusive coronary arteries and patients with obstructive coronary arteries. Prevalence of CMVD is significantly higher in patients with obstructive coronary arteries than in patients with non-obstructive coronary arteries. The CMVD severity is similar between the two groups.

[Outcomes of implanting porcine small intestinal submucosa mesh in rabbit vesicovaginal space]

Objective: To assess surgical outcomes of implanted porcine small intestinal submucosa (SIS) mesh in the rabbit vesicovaginal space (VVS) and explore its application value in pelvic floor reconstruction surgery. Methods: Sixteen male rabbits were randomly divided into four groups, and each group had four rabbits. All groups of rabbits were implanted with SIS mesh in the vesicovaginal space. They were humanely killed after a postoperative period of 7, 30, 90 and 180 days by group. The grafted area was removed with the surrounding bladder and vaginal tissues. The specimens were embedded in paraffin and then stained with HE and Masson's trichrome stains for visual observations, cells counts, and assessment of tissues and collagen fibers. Results: (1) After HE staining, a large number of inflammatory response cells mainly eosinophils and lymphocytes infiltrated around the SIS mesh in 7 days group, and neovascularization was observed, the infiltration area of inflammatory response cells further increased in 30 days group, the infiltration area of inflammatory response cells significantly reduced in 90 days group, while the inflammatory response basically subsided in 180 days group. (2) After Masson's trichromestaining, the collagen structure of SIS mesh in 7 days group was clear and intact. While, the collagen structure of SIS mesh was partially degraded in 30 days group, the SIS meshes of 4 rabbits were completely degraded, but the collagen fragments of SIS remained in 90 days group. In 180 days group, the SIS mesh of all rabbits was degraded, and one of them had the formation of new collagen fibers. Conclusions: SIS mesh implanted into the VVS of rabbits can lead to a transient non infective inflammatory reaction, which could be completely degraded and a small amount of new collagen fibers could be produced after 180 days of implantation. Which shown that SIS mesh should be used cautiously in pelvic floor reconstruction surgery.

TRPV1 activation alleviates cognitive and synaptic plasticity impairments through inhibiting AMPAR endocytosis in APP23/PS45 mouse model of Alzheimer's disease

Alzheimer's disease (AD) is one of the most common causes of neurodegenerative diseases in the elderly. The accumulation of amyloid‐β (Aβ) peptides is one of the pathological hallmarks of AD and leads to the impairments of synaptic plasticity and cognitive function. The transient receptor potential vanilloid 1 (TRPV1), a nonselective cation channel, is involved in synaptic plasticity and memory. However, the role of TRPV1 in AD pathogenesis remains largely elusive. Here, we reported that the expression of TRPV1 was decreased in the brain of APP23/PS45 double transgenic AD model mice. Genetic upregulation of TRPV1 by adeno‐associated virus (AAV) inhibited the APP processing and Aβ deposition in AD model mice. Meanwhile, upregulation of TRPV1 ameliorated the deficits of hippocampal CA1 long‐term potentiation (LTP) and spatial learning and memory through inhibiting GluA2‐containing α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid receptor (AMPAR) endocytosis. Furthermore, pharmacological activation of TRPV1 by capsaicin (1 mg/kg, i.p.), an agonist of TRPV1, dramatically reversed the impairments of hippocampal CA1 LTP and spatial learning and memory in AD model mice. Taken together, these results indicate that TRPV1 activation effectively ameliorates cognitive and synaptic functions through inhibiting AMPAR endocytosis in AD model mice and could be a novel molecule for AD treatment.

MKP-1 reduces Aβ generation and alleviates cognitive impairments in Alzheimer's disease models

Mitogen-activated protein kinase (MAPK) phosphatase 1 (MKP-1) is an essential negative regulator of MAPKs by dephosphorylating MAPKs at both tyrosine and threonine residues. Dysregulation of the MAPK signaling pathway has been associated with Alzheimer's disease (AD). However, the role of MKP-1 in AD pathogenesis remains elusive. Here, we report that MKP-1 levels were decreased in the brain tissues of patients with AD and an AD mouse model. The reduction in MKP-1 gene expression appeared to be a result of transcriptional inhibition via transcription factor specificity protein 1 (Sp1) cis-acting binding elements in the MKP-1 gene promoter. Amyloid-β (Aβ)-induced Sp1 activation decreased MKP-1 expression. However, upregulation of MKP-1 inhibited the expression of both Aβ precursor protein (APP) and β-site APP-cleaving enzyme 1 by inactivating the extracellular signal-regulated kinase 1/2 (ERK)/MAPK signaling pathway. Furthermore, upregulation of MKP-1 reduced Aβ production and plaque formation and improved hippocampal long-term potentiation (LTP) and cognitive deficits in APP/PS1 transgenic mice. Our results demonstrate that MKP-1 impairment facilitates the pathogenesis of AD, whereas upregulation of MKP-1 plays a neuroprotective role to reduce Alzheimer-related phenotypes. Thus, this study suggests that MKP-1 is a novel molecule for AD treatment.

[Cost-effectiveness analysis of rabies immunization strategy based on dynamic-decision tree model]

Objective: To evaluate the cost-utility of different immunization strategies for rabies in China, and to provide a reference for determining the optimal immunization strategy. Methods: The system dynamics model was used to simulate the epidemic of canine rabies and a decision tree model was conducted to analysis different immune strategies. Relevant probabilities were obtained through literature search and on-site investigation. Sensitivity analysis was used to explore the important influenced factors. Results: At baseline, from a social perspective, 70% vaccination of dogs was the optimal strategy compared to current vaccination strategy (43% vaccination in dogs, human category-Ⅱ exposure vaccination/category-Ⅲ exposure vaccination combined with RIG). The total cost was 14 084 354 CNY, and the total utility value was 22 078 616.23 QALYs, and the incremental cost-utility ratio was-62 148 147 CNY/QALY; if human vaccination was considered, 55% vaccination of dogs combined with strategy one was the optimal strategy, its incremental cost-utility ratio was-444 620 557 CNY/QALY. The probability that an injured dog carries rabies virus was the most sensitive parameter. When it was greater than 0.005 03, strategy four was the optimal strategy. When it was less than 82/100 000, strategy one was the optimal strategy; when it was between 82/100 000 and 120/100 000, strategy two was the optimal strategy; when it was between 120/100 000 and 503/100 000, strategy two was the optimal strategy. Conclusion: It was conducive to increase the vaccination coverage of canine for the prevention and control of rabies.

P841Derivation and validation of novel score system for predicting all-cause death and myocardial infarction in coronary artery ectasia

Background

Coronary artery ectasia (CAE) bears high risk of death and myocardial infarction. Risk stratification in CAE patients is crucial for their management, but there were no risk score systems intended for risk evaluation of CAE patients so far.

Methods

In a retrospective cohort of 595 patients with CAE, we collected the baseline characteristics (clinical history, biomarkers and quantitative coronary angiography variables). Follow-up were conducted and the end-point event was the composite of all-cause death and non-fatal myocardial infarction. The candidate predictors of end-point event were analyzed using Cox proportional hazards regression models to derive a risk score in the form of nomogram. The predictive performance and discriminative ability of the novel nomogram were determined by concordance index (C-index) and calibration curve, that were validated internally. Risk stratification by nomogram-predicted risk score was further evaluated.

Results

During a median follow-up time of 62.3 months, 26 all-cause deaths and 37 non-fatal myocardial infarctions were identified. The final risk-prediction model named ABCD-CAE score included four items: age (A), Brain natriuretic peptide (B), high sensitivity C-reactive protein (C) and maximum Dilated area of ectatic lesions (D). The nomogram yielded a C-index for end-point event of 0.72 (95% confidence interval, 0.64 - 0.79). The calibration curve demonstrated that there is good agreement between prediction by nomogram and actual observation of end-point events. Compared with the low-risk group (score ≤100), the risk of composite events was significantly increased in the intermediate-risk group (score: 100–130) and high-risk group (score >130) [hazard ratio (95% confidence interval): 2.23 (1.23–4.06), P=0.008 and 7.02 (3.81–12.97), P<0.001 respectively].

ABCD-CAE nomogram for risk prediction

Conclusions

The ABCD-CAE score is a simple four-item risk score, that provides a clinically useful tool for the risk prediction of all-cause death and myocardial infarction in patients with CAE. This user-friendly tool might support clinical decision making for the management of CAE.

[Efficacy and side effect analysis of paclitaxel liposome for neoadjuvant chemotherapy in locally advanced cervical cancer]

Objective: To investigate the efficacy and side effect of paclitaxel liposome for neoadjuvant chemotherapy (NACT) in locally advanced cervical cancer. Methods: This study were included 265 cervical cancer patients staging Ⅰb2 and Ⅱa2 who underwent paclitaxel-platinum NACT followed by radical surgery from June 2008 to December 2016 in the Cancer Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences. All patients were classified into two groups with 106 patients in paclitaxel liposome group and 159 patients in traditional paclitaxel group. The difference in clinicopathologic characteristics, efficacy and side effect were analyzed retrospectively between the two groups. Results: (1) Clinicopathologic characteristics: there were no significant difference in clinicopathologic characteristics between the two groups, including age, body mass index, clinical stage, pathological histology, cycles of NACT, combined platinum regimen, lymph-vascular space invasion, lymph node metastasis, deep stromal invasion, and postoperative adjuvant therapy (all P>0.05). (2) Efficacy: after NACT, the overall response occurred in 90 (15 complete response plus 75 partial response) of 106 cases in the paclitaxel liposome group versus 131 (21 complete response plus 110 partial response) of 159 cases in the traditional paclitaxel group without statistical significance (84.9% vs 82.4%; χ(2)=0.291, P=0.590). A total of 248 patients received surgery after NACT and were evaluable in survival. The 5-year recurrence-free survival (RFS) rate and 5-year overall survival (OS) rate of these patients was 85.1% and 88.2%. The 5-year RFS rate in the paclitaxel liposome group was 85.9% compared with 85.2% in the traditional paclitaxel group, while the corresponding 5-year OS rate was 88.5% and 88.7%, respectively. There was no statistically significant difference in efficacy between the two groups (P=0.968, P=0.797). (3) Side effect: the incidence of allergic reaction between the paclitaxel liposome group and the traditional paclitaxel group was 0 versus 1.9% (3/159) without statistical significance (P=0.277). But the incidence of neurotoxicity in the paclitaxel liposome group significantly decreased compared with the traditional paclitaxel group (6.6% vs 15.7%, P<0.05), as well as the incidence of alopecia (67.9% vs 79.2%, P<0.05) and myalgia (17.9% vs 28.9%, P<0.05). However, significant differences were not found in terms of hematological toxicity, gastrointestinal reaction, and hepatic function damage (P>0.05). Conclusion: In paclitaxel-platinum NACT of local advanced cervical cancer, paclitaxel liposome can achieve similar efficacy compared with traditional paclitaxel, but paclitaxel liposome is helpful in decreasing the toxicity of neurotoxicity, alopecia and myalgia.

p97 regulates GluA1 homomeric AMPA receptor formation and plasma membrane expression

The α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid subtype glutamate receptors (AMPARs) mediate the fast excitatory synaptic transmission in the mammalian brain and are important for synaptic plasticity. In particular, the rapid insertion of the GluA1 homomeric (GluA1-homo) AMPARs into the postsynaptic membrane is considered to be critical in the expression of hippocampal CA1 long-term potentiation (LTP), which is important for certain forms of learning and memory. However, how the formation and trafficking of GluA1-homo AMPARs are regulated remains poorly understood. Here, we report that p97 specifically interacts with and promotes the formation of GluA1-homo AMPARs. The association with p97 retains GluA1-homo AMPARs in the intracellular compartment under basal conditions, and its dissociation allows GluA1-homo AMPARs to be rapidly inserted into the postsynaptic membrane shortly after LTP induction. Thus, our results shed lights into the molecular mechanisms by which p97 regulates GluA1-homo AMPARs formation and trafficking, thereby playing a critical role in mediating synaptic plasticity.

Neuroprotective Effects of Ginsenoside Rf on Amyloid-β-Induced Neurotoxicity in vitro and in vivo

Alzheimer's disease (AD) is a neurodegenerative disease characterized by the deposition of amyloid-β peptides (Aβ). Aβ accumulation leads to the formation of neurofibrillary tangles, inflammation, axonal injury, synapse loss, and neuronal apoptosis. Thus, reducing Aβ levels should exert a neuroprotective effect against AD. Ginsenoside Rf, an extract from Panax notoginseng, has potent anti-fatigue, anti-nociception, anti-oxidation, and anti-inflammation properties. However, it is unclear whether ginsenoside Rf is effective in the treatment of AD. Here, we reported that ginsenoside Rf could significantly attenuate Aβ-induced apoptosis in N2A cells, as reflected by a dramatic increase in mitochondrial membrane potential and decrease in Ca2 + concentration, reactive oxygen species, and active caspase-3 expression. Meanwhile, ginsenoside Rf could alleviate the Aβ-induced inflammation reaction, such as the decrease of interferon-gamma (IFN-γ) and active caspase-1 expression and the increase of interleukin-13. Furthermore, we also found that Rf is able to accelerate Aβ clearance and subsequently reduces Aβ level in N2A cells stably transfected with human Swedish mutant APP695 (N2A-APP). More importantly, daily Rf treatment (20 mg/kg, i.p.) throughout the experiment dramatically improved spatial learning and memory in Aβ42-induced mouse model of AD. Taken together, these results indicate that ginsenoside Rf may decrease Aβ-induced neurotoxicity and memory decline via anti-inflammatory response during AD development, suggesting that Rf may be a potential therapeutic agent for treating AD.

Antimicrobial resistance and virulence genes of Streptococcus isolated from dairy cows with mastitis in China

Streptococcus is a major mastitis-causing pathogen in dairy cows. To investigate the prevalence, antimicrobial resistance and virulence gene of Streptococcus in mastitic milk, a total of 735 mastitic raw milk samples from dairy cows in 11 provinces of China were collected and tested. Antimicrobial resistance of Streptococcus isolates was determined by disc diffusion against 8 classes 29 antimicrobial agents, and Streptococcus resistant genes and virulence genes were determined by PCR and agarose gel electrophoresis. A total of 64 (8.71%) isolates of Streptococcus were isolated and identified using biochemical profiling, including 22 isolates of Streptococcus agalactiae, 13 isolates of Streptococcus dysgalactiae, and 29 isolates of Streptococcus uberis. Out of 64 resistant Streptococcus isolates, all isolates (100%) were resistant to 3 or more antimicrobials. The most frequency (n = 18, 28.12%) of the isolates were multi-resistant to 5-7 antimicrobials and the highest multi-resistant number was 29 (n = 1, 1.56%). Streptococcus isolates had the highest resistance rate to tetracycline (98.44%) and oxacillin (98.44%), followed by penicillin G (96.88%) and doxycycline (96.88%), and the lowest resistance was observed with respect to ciprofloxacin (1.56%). A total of 16 antimicrobials resistance genes with 25 combination patterns were detected in the isolates. The gene combination of Sul1/Sul2/Sul3 + gyrA/parC + cat1/cat2 was the most common pattern (12.5%). The correlation between resistant phenotypes and resistance genes in Streptococcs was 35.87%. A total of 7 virulence genes were detected and 59 (92.19%) isolates harbored at least one gene. Twenty-four classes of gene patterns were found in the isolates and the patterns of bca (9.38%) and cfb (9.38%) were the most prevalent form. In conclusion, the issue of drug resistance of Streptococcus is still a great concern in cattle health in China.

[Comparative study of three-dimensional versus two-dimensional laparoscopic C1 radical hysterectomy for cervical cancer]

Objective: To compare the clinical effects and the subjective perception of surgeons with three-dimensional (3D) and two-dimensional (2D) laparoscopic C1 radical hysterectomy surgeries for cervical cancer. Methods: The retrospective cohort study was conducted. The clinicopathological data of 101 patients with cervical cancer who received C1 laparoscopic radical hysterectomy (C1-LRH) surgery from June 2015 to August 2017 were collected. Of all patients, 42 cases undergoing 3D laparoscopic surgery and 59 cases undergoing 2D laparoscopic surgery were respectively allocated into the C1-3DLRH group or C1-2DLRH group. The clinical effect and the subjective perception of surgeons were compared between the two groups. Results: (1) There was no significant difference between the C1-3DLRH group and C1-2DLRH group in terms of age, body mass index (BMI), International Federation of Gynecology and Obstetrics (FIGO) stage, pathologic type, etc. (all P>0.05). Compared with C1-2DLRH group, the operation time was significantly shortened [(192±54) vs (221±54) minutes, P<0.01], blood loss was significantly less [(102±88) vs (167±117) ml, P<0.01], and the success rate of inferior hypogastric plexus (IHP) bladder branch preservation was significantly increased [86% (36/42) vs 66% (39/59), P<0.05] in C1-3DLRH group. There were no significant difference in the number of lymph nodes, the incidence of operative complications, the infection rate, the time of catheterization and the length of hospitalization between the two groups (all P>0.05). The long-term bladder function was evaluated at the twelfth month after operation, 39 patients in the C1-3DLRH group and 53 patients in the C1-2DLRH group were completed the survey. The results showed that 13% (5/39) of the patients in the C1-3DLRH group had long-term bladder dysfunction, which was lower than that 21% (11/53) of the C1-2DLRH group, but there was no significant difference between the two groups (χ(2)=0.980, P=0.322). (2) A total of 251 laparoscopic surgeons questionnaires were eligible. The incidence of side effects in the first and second generation of 3D and 2D laparoscopic surgeons was 20.4% (10/49), 6.9% (6/87) and 3.5% (4/115), respectively. The incidence of side effects in the first generation of 3D laparoscopic surgeons was higher than that in the second generation of 3D (χ(2)=5.463, P=0.019) and 2D laparoscopic surgeons (χ(2)=12.475, P<0.01). There was no difference between the second generation of 3D and 2D laparoscopic surgeons (χ(2)=1.208, P=0.272). Conclusions: 3D laparoscopy is advantageous to the preservation of autonomic nerve in C1-LRH operation and may improve the quality of operation compared with 2D laparoscopy. The second generation of 3D laparoscopic device might overcome the side effects of the surgeons.

Flaxseed extract induces apoptosis in human breast cancer MCF-7 cells

Significant evidence indicated that flaxseed (Linum usitatissimum) possesses various positive health aspects such as reducing the risk of cancer and cardiovascular diseases. The fatty acids are considered to be responsible for these benefits of flaxseed. Herein, the in vitro effects of flaxseed extract on the growth and apoptosis of human breast cancer MCF-7 cells were investigated. The MCF-7 cells treated with flaxseed extract showed a dose-dependent decrease in cell viability. The flaxseed extract induced reactive oxygen species and the flow cytometric analysis demonstrated that flaxseed fatty acids triggered apoptosis of MCF-7 cells, which was also shown by the loss of mitochondrial membrane potential and caspase cascade reaction. Thus, the flaxseed extract regulated the growth of MCF-7 cells and induced apoptosis. Eventually, the flaxseed could be used as a dietary supplement to prevent breast cancer.

Loss of Synapse Repressor MDGA1 Enhances Perisomatic Inhibition, Confers Resistance to Network Excitation, and Impairs Cognitive Function

Synaptopathies contributing to neurodevelopmental disorders are linked to mutations in synaptic organizing molecules, including postsynaptic neuroligins, presynaptic neurexins, and MDGAs, which regulate their interaction. The role of MDGA1 in suppressing inhibitory versus excitatory synapses is controversial based on in vitro studies. We show that genetic deletion of MDGA1 in vivo elevates hippocampal CA1 inhibitory, but not excitatory, synapse density and transmission. Furthermore, MDGA1 is selectively expressed by pyramidal neurons and regulates perisomatic, but not distal dendritic, inhibitory synapses. Mdga1^-/- hippocampal networks demonstrate muted responses to neural excitation, and Mdga1^-/- mice are resistant to induced seizures. Mdga1^-/- mice further demonstrate compromised hippocampal long-term potentiation, consistent with observed deficits in spatial and context-dependent learning and memory. These results suggest that mutations in MDGA1 may contribute to cognitive deficits through altered synaptic transmission and plasticity by loss of suppression of inhibitory synapse development in a subcellular domain- and cell-type-selective manner.

Synaptotagmin-3 drives AMPA receptor endocytosis, depression of synapse strength, and forgetting

Forgetting is important. Without it, the relative importance of acquired memories in a changing environment is lost. We discovered that synaptotagmin-3 (Syt3) localizes to postsynaptic endocytic zones and removes AMPA receptors from synaptic plasma membranes in response to stimulation. AMPA receptor internalization, long-term depression (LTD), and decay of long-term potentiation (LTP) of synaptic strength required calcium-sensing by Syt3 and were abolished through Syt3 knockout. In spatial memory tasks, mice in which Syt3 was knocked out learned normally but exhibited a lack of forgetting. Disrupting Syt3:GluA2 binding in a wild-type background mimicked the lack of LTP decay and lack of forgetting, and these effects were occluded in the Syt3 knockout background. Our findings provide evidence for a molecular mechanism in which Syt3 internalizes AMPA receptors to depress synaptic strength and promote forgetting.

[Effect of serum HGF and CK18 in patients with laryngeal cancer on postoperative prognosis]

Objective: To investigate the correlation between the levels of serum cytokeratin 18 (CK18) and hepatocyte growth factor (HGF) and tumor stage and prognosis in patients with laryngeal carcinoma. Method: Patients with laryngeal cancer who were admitted to our hospital from January 2012 to December 2013 were enrolled. Blood samples were collected for CK18 and HGF detection, and postoperative prognosis data were collected at regular follow-up. Result: The serum CK18 and HGF concentration of patients with poorly differentiated tumor, high tumor grade and clinical stage were significantly higher than those with well differentiated tumor, low tumor grade and low clinical stage (P<0.05). The 5-year survival rate (69.9%) of patients with laryngeal cancer in the high CK18 group was significantly lower than that in the low CK18 group (92.3%) (P<0.05), and the 5-year survival rate (71.1%) of patients with laryngeal cancer in the high HGF group was significantly lower than that in the low HGF group (94.2%) (P<0.05). The results of univariate analysis showed that tumor type, differentiation, T grade, N grade and clinical stage affected the survival rate of patients with laryngeal cancer. Cox regression model analysis showed high CK18 and high HGF levels were risk factors for poor prognosis ［CK18 HR: 2.594 (1.558-4.318); P<0.001, HGF HR: 2.671 (1.605-4.446); P<0.001］. Conclusion:The results suggested that serum CK18 and HGF levels can be used as prognostic and disease monitoring biomarkers for laryngeal cancer.

Wave propagation in tunable lightweight tensegrity metastructure

Lightweight metastructures are designed consisting of prismatic tensegrity building blocks which have excellent strength-to-weight ratio and also enable unique compression-torsion coupling. A theoretical model with a coupled axial-torsional stiffness is first developed to study the band structures of the proposed lightweight metastructures. Then, various unit cell designs are investigated for bandgap generations at desired frequency ranges. Broadband full-wave attenuation is found in the tensegrity metastructure with special opposite-chirality. Furthermore, tunable stiffness in the prismatic tensegrity structure is investigated and 'small-on-large' tunability is achieved in the metastructure by harnessing the geometrically nonlinear deformation through an external control torque. Prestress adjustment is also investigated for fine tuning of the band structure. Finally, frequency response tests on the finite metastructures are preformed to validate their wave attenuation ability as well as their wave propagation tunability. The proposed tensegrity metastructures could be very useful in various engineering applications where lightweight and tunable structures with broadband vibration suspension and wave attenuation ability are in high demand.

[Primary prevention by hepatitis B vaccine on liver cancer in high incidence area of China]

Objective: Incidence of primary liver cancer (PLC) in China is mostly related to chronic infection of hepatitis B virus (HBV). Qidong was one of the endemic areas with high incidence of PLC in China before 2000. We conducted a series of studies regarding on PLC etiological prevention during the past decades to develop better primary prevention strategies for PLC. Methods: Qidong Hepatitis B Intervention Study was conducted in 1983-1990. A total of 41 182 newborns were randomly assigned to vaccination group and 40 211 (97.64%) of them completed the three-dose, 5 µg-plasma-derived hepatitis B (HB) vaccination series at age 0, 1, 6 month. Among them, 28 988 participants received one-dose 10 µg recombinant HB booster vaccination at age 10-14 years. A total of 41 730 newborns were randomly assigned to the control group. When they were at age 10-14 years, 23 368 participants received the catch-up vaccination with three-dose, 10 µg-recombinant HB vaccine. Two cross-sectional HBV serology surveys were conducted in 1996-2000 and 2008-2012. Information on PLC incidence and mortality of chronic liver diseases were collected through cancer registry and vital statistics until December 31, 2016. Cox proportional hazard models were employed to compute hazard ratio (HR) of PLC and other liver diseases for the participants with neonatal HB vaccination or catch-up vaccination, and the protective efficacy was also calculated. Results: During serologic survey in 1996-2000, a total of 22 689 participants in vaccination group and 12 395 participants in control group donated blood samples. The HBsAg seropositive rates in the vaccination group was 2.16% (491/22 689), which is significantly lower than that of control group (9.08%, 1 126/12 395) (χ²=896.61, P<0.001). During serologic survey in 2008-2012, a total of 17 386 participants in vaccination group and 18 060 participants in control group donated blood samples. The HBsAg seropositive rates in the vaccination group was 1.83% (319/17 386), which is still significantly lower than that of control group (6.77%,1 222/18 060) (χ²=518.05, P<0.001). By December 31, 2016, 4 cases of PLC in the vaccination group and 17 cases of PLC were identified in the vaccination and control group, respectively. The estimated efficacy of neonatal HB vaccination on HBsAg seroprevalence in childhood (at age 10-11 years), early adulthood (at age 19-28 years) and incidence rate of PLC at age below 33 years was 79% (95%CI: 76%-81%), 74% (95%CI: 71%-78%) and 79% (95%CI: 36%-93%), respectively. The estimated efficacy of three-dose, 10 µg-recombinant HB catch-up vaccination in early adulthood is 21% (95%CI: 11%-30%), which is significantly lower than that of neonatal HB vaccination. Conclusion: HB vaccination to neonates/infants is crucial against chronic HBV infection in childhood through young adulthood, and subsequently reduced the risk of PLC in young adults.

[The influence of molecular classification of breast cancer on the safety of breast-conserving surgery]

Objective: To analyze the relationship between the breast cancer molecular classification and the prognosis of patients underwent breast-conserving therapy and to discuss the safety of the breast conserving surgery from the choice of operation in terms of breast cancer molecular classification. Methods: Clinical data of 618 patients with breast-conserving therapy in Tianjin Medical University Cancer Institute and Hospital from August 2005 to August 2010 were analyzed retrospectively. According to the molecular classification when breast cancer was diagnosed, patients were subdivided into five groups, including Luminal A, Luminal B1, Luminal B2, HER-2-positive and Triple-negative. Clinicopathological characteristics and prognosis were compared among five groups and the influencing factors of local recurrence, distant metastasis and overall survival were analyzed. Results: Among 618 patients, there were 148 cases Luminal A, 231 cases Luminal B1, 63 cases Luminal B2, 40 cases HER-2-positive and 136 cases Triple-negative. The age, family history, TNM stage, calcification, histological grade, pathological type and response to endocrine therapy of these 5 molecular types of breast cancer patients were significantly different (all P<0.05). The 5-year local regional recurrence-free survival rates of Luminal A, Luminal B1, Luminal B2, HER-2-positive and Triple-negative were 99.3%, 98.7%, 98.4%, 94.9% and 95.9%, respectively, without significant differences (P=0.104). The 5-year distant metastasis-free survival rates of these 5 types were 97.3%, 95.7%, 93.7%, 87.5% and 91.4%, respectively, with significant differences (P=0.013). Moreover, the 5-year overall survival rates of these 5 types were 98.6%, 97.8%, 98.4%, 92.5% and 95.6%, respectively, without significant differences (P=0.153). Multifactor analysis showed that radiotherapy (HR=0.036, P=0.049) and the number of lymph node metastases (HR=10.72, P=0.004) were independent factors of local recurrence of breast cancer patients underwent breast-conserving therapy. The age (HR=0.369, P=0.046), status of surgical margin (HR=5.486, P=0.007), number of lymph node metastases (HR=2.882, P=0.023) and molecular typing (HR=5.191, P=0.008) were independent factors of distant metastasis of above breast cancer patients. None of the factors were found to be independent factors of the overall survival of these breast cancer patients. Conclusions: Breast conserving therapy does not increase the risks of local recurrence and death of HER-2-positive and Triple-negative breast cancer patients. Therefore, breast conserving therapy can be accepted by patients with HER-2-positive and Triple-negative breast cancer.