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Anodized titania nanotubes have been considered as an effective coating for bone implants due to their ability to induce osteogenesis, whereas the osteogenic mechanism is not fully understood. Our previous study has revealed the potential role of autophagy in osteogenic regulation of nanotubular surface, whereas how the autophagy is activated remains unknown. In this study, we focused on the cell membrane curvature-sensing protein Bif-1 and its effect on the regulation of autophagy. Both autophagosomes formation and autophagic flux were enhanced on the nanotubular surface, as indicated by LC3-II accumulation and p62 degradation. In the meanwhile, the Bif-1 was significantly upregulated, which contributed to autophagy activation and osteogenic differentiation through Beclin-1/PIK3C3 signaling pathway. In conclusion, these findings have bridged the gap between extracellular physical nanotopography and intracellular autophagy activation, which may provide a deeper insight into the signaling transition from mechanical to biological across the cell membrane., (© 2024 IOP Publishing Ltd.)

Objective: Diabetes mellitus (DM) is one of the major diseases in the world. Nuclear medicine imaging may be able to detect functional status of pancreatic β cells in vivo, which might elucidate the pathological mechanisms of diabetes and develop individualized treatment plans. In this study, we evaluated the ability of [ 125 I]ADAM, a serotonin transporter (SERT) imaging agent, as a probe for detecting pancreatic β-cell mass (BCM)., Methods: In vitro cell studies were evaluated in INS-1 cells (rat islet β cell line). Biodistribution studies were performed in male normal Sprague-Dawley rats and alloxan-induced type 1 diabetes mellitus (T1DM) rats. Distribution and expression of SERT protein in pancreas of rats were also measured by immunofluorescence staining and Western blot., Results: In vitro cell studies showed that the concentration of [ 125 I]ADAM associated with the INS-1 cells was increased gradually with incubation time, and the SERT specific inhibitor, escitalopram, exhibited the inhibitory effect on this interaction. Biodistribution studies also showed that the uptake of [ 125 I]ADAM in the pancreas of normal rats was decreased in the presence of escitalopram. However, in the T1DM rat model with a significant β cells reduction, the uptake of pancreas was increased when compared with the control. Through immunofluorescence staining and Western blot, it was found that both the endocrine and exocrine cells of the normal pancreas expressed SERT protein, and the level of SERT protein in the exocrine cells was higher than islets. In the diabetic state, the expression of SERT in the exocrine cells was further increased., Conclusions: The SERT imaging agent, [ 125 I]ADAM, at the present form will not be suitable for imaging β cells, specifically because there were extraordinarily high non-specific signals contributing from the exocrine cells of pancreas. In addition, we noticed that the level of SERT expression was abnormally elevated in the diabetic state, which might provide an unexpected target for studying the pathological mechanisms of diabetes., Competing Interests: Declaration of competing interest All of the authors declare no conflict of interest associated with this work., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objectives: Restenosis is one of the important factors affecting the effectiveness of percutaneous transluminal angioplasty and stenting in the treatment of intracranial atherosclerotic stenosis. We aimed to clarify whether recruitable collateral flow could cause restenosis in patients treated with percutaneous transluminal angioplasty and stenting., Material and Methods: Our study retrospectively analyzed patients with symptomatic severe intracranial atherosclerotic stenosis (≥70%) who underwent percutaneous transluminal angioplasty and stenting. We enrolled 28 patients with restenosis and 71 patients without restenosis. We analyzed baseline data, perioperative events, and follow-up results of patients in the two groups. Binary logistic regression analysis was used to identify restenosis predictors., Results: For preoperative stroke, the restenosis group had a greater likelihood of having a previous stroke (89.3%), which was less prevalent in the non-restenosis group (66.2%) ( P = 0.020). The restenosis group had a higher rate of re-stroke (21.4 vs. 4.2%, P = 0.022). After binary logistic regression analysis, collateral circulation and residual stenosis were independent risk factors of restenosis, with overall risk (95% confidence intervals) of 5.034 (1.484-4.066, P < 0.001) and 1.064 (1.006-1.125, P = 0.030), respectively. Restenosis risk increased 1.456-fold for each collateral circulation grade increase. However, for each 1% increase in residual stenosis, restenosis risk increased by 5.9% ( P = 0.03). The chance of restenosis is minimal when the residual stenosis rate after percutaneous transluminal angioplasty and stent implantation is 15.85%., Conclusions: Good collateral circulation was significantly associated with restenosis in patients undergoing intracranial angioplasty, the residual stenosis rate tends to be 15.85% to reduce restenosis risk. Compared to patients with restenosis, those without restenosis have a low stroke risk during follow-up., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Li, Sun, Liu, Liu, Li and Zhang.)

Objectives: This work aimed to analyse the risk factors for poor outcomes and mortality among patients with anterior large vessel occlusion (LVO) ischaemic stroke, despite successful recanalisation., Setting and Participants: This study conducted a secondary analysis among patients who underwent successful recanalisation in the CAPTURE trial. The trial took place between March 2018 and September 2020 at 21 sites in China. The CAPTURE trial enrolled patients who had an acute ischaemic stroke aged 18-80 years with LVO in anterior circulation., Interventions: Thrombectomy was immediately performed using Neurohawk or the Solitaire FR after randomisation in CAPTURE trial. Rescue treatment was available for patients with severe residual stenosis caused by atherosclerosis., Primary and Secondary Outcome Measures: The primary goal was to predict poor 90-day survival or mortality within 90 days post-thrombectomy. Univariate analysis, using the χ 2 test or Fisher's exact test, was conducted for each selected factor. Subsequently, a multivariable analysis was performed on significant factors (p≤0.10) identified through univariate analysis using the backward selection logistic regression approach., Results: Among the 207 recruited patients, 79 (38.2%) exhibited poor clinical outcomes, and 26 (12.6%) died within 90 days post-thrombectomy. Multivariate analysis revealed that the following factors were significantly associated with poor 90-day survival: age ≥67 years, internal carotid artery (ICA) occlusion (compared with middle cerebral artery (MCA) occlusion), initial National Institutes of Health Stroke Scale (NIHSS) score ≥17 and final modified Thrombolysis in Cerebral Infarction (mTICI) score 2b (compared with mTICI 3). Additionally, the following factors were significantly associated with mortality 90 days post-thrombectomy: initial NIHSS score ≥17, ICA occlusion (compared with MCA occlusion) and recanalisation with more than one pass., Conclusions: Age, NIHSS score, occlusion site, mTICI score and the number of passes can be independently used to predict poor 90-day survival or mortality within 90 days post-thrombectomy., Trial Registration Number: NCT04995757., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

The exploration of cell response to nanotopography has attracted considerable attentions for years. This article focuses on the influence of nanotopography on the intracellular Ca 2+ dynamics, the most ubiquitous but ignored second messenger. The classic titanium nanotubes (NT) were fabricated by anodization to formulate nanoporous surfaces. Firstly, the store operative calcium entry (SOCE) in endoplasmic reticulum (ER) and functional Ca 2+ release-activated Ca 2+ (CRAC) channels were significantly enhanced on NT surfaces that revealed by live-cell Ca 2+ imaging and fluorescence resonance energy transfer (FRET) identification of orai1-stim1 connection. To investigate the potential implication of Ca 2+ elevation, the dynamic cell migration trajectory was monitored by a self-made holder, which could not only be suitable for the opaque implant surface but also guarantee the focus fields identical during samples shifting. The cell migration on NT surface was more vigorous and rapid, which was correlated with higher focal adhesion proteins expression, Ca 2+ -dependent calpain activity and stim1 level. In conclusion, this study has confirmed the novel ER Ca 2+ hemostasis pathway on nanosurfaces and its crucial role in cell migration regulation, which may help for more biofavorable implant surface design., (© 2023. The Author(s).)

Circulating neutrophils are activated shortly after stroke and in turn affect the fate of ischemic brain tissue, and microRNAs (miRNA) participate in regulating neuroinflammation. We probed the role of neutrophilic miRNA in ischemic stroke. miR-193a-5p was decreased in circulating neutrophils of acute ischemic stroke (AIS) patients and healthy controls. In another set of AIS patients treated with recombinant tissue plasminogen activator, higher neutrophilic miR-193a-5p levels were associated with favorable outcomes at 3 months and non-symptomatic intracerebral hemorrhage. An experimental stroke model and human neutrophil-like HL-60 cells were further transfected with agomiR-193a-5p/antagomiR-193a-5p or ubiquitin-conjugating enzyme V2 (UBE2V2)-siRNA prior to model induction for in vivo and in vitro studies. Results of 2,3,5-triphenyl tetrazolium chloride staining and neurological function evaluations at post-experimental stroke showed that intravenous agomiR-193a-5p transfusion protected against ischemic cerebral injury in the acute stage and promoted neurological recovery in the subacute stage. This protective role was suggested to correlate with neutrophil N2 transformation based on the N2-like neutrophil proportions in the bone marrow, peripheral blood, and spleen of the experimental stroke model and the measurement of neutrophil phenotype-associated molecule levels. Mechanistically, analyses indicated that UBE2V2 might be a target of miR-193a-5p. Cerebral injury and neuroinflammation aggravated by miR-193a-5p inhibition were reversed by UBE2V2 silencing. In conclusion, miR-193a-5p protects against cerebral ischemic injury by restoring neutrophil N2 phenotype-associated neuroinflammation suppression, likely, in part, via UBE2V2 induction., (© 2022. The Author(s).)

Background: Stent placement can be an effective treatment for patients with symptomatic intracranial stenosis (sICAS) and hemodynamic impairment (HI). However, the association between lesion length and the risk of recurrent cerebral ischemia (RCI) after stenting remains controversial. Exploring this association can help predict patients at higher risk for RCI and develop individualized follow-up schedules., Method: In this study, we provided a post-hoc analysis of a prospective, multicenter registry study on stenting for sICAS with HI in China. Demographics, vascular risk factors, clinical variables, lesions, and procedure-specific variables were recorded. RCI includes ischemic stroke and transient ischemic attack (TIA), from month 1 after stenting to the end of the follow-up period. Smoothing curve fitting and segmented Cox regression analysis were used to analyze the threshold effect between lesion length and RCI in the overall group and subgroups of the stent type., Results: The non-linear relationship between lesion length and RCI was observed in the overall population and subgroups; however, the non-linear relationship differed by subgroup of stent type. In the balloon-expandable stent (BES) subgroup, the risk of RCI increased 2.17-fold and 3.17-fold for each 1-mm increase in the lesion length when the lesion length was <7.70 mm and >9.00 mm, respectively. In the self-expanding stent (SES) subgroup, the risk of RCI increased 1.83-fold for each 1-mm increase in the lesion length when the length was <9.00 mm. Nevertheless, the risk of RCI did not increase with the length when the lesion length was >9.00mm., Conclusion: A non-linear relationship exists between lesion length and RCI after stenting for sICAS with HI. The lesion length increases the overall risk of RCI for BES and for SES when the length was <9.00 mm, while no significant relationship was found when the length was >9.00 mm for SES., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Zhang, Gong, Meng, Li, Liu, Zhang and Wang.)

Objective: The objective of this study was to assess the safety, feasibility, and outcomes of endovascular recanalization for symptomatic intracranial internal carotid and middle cerebral artery occlusion lasting longer than 72 h., Methods: Thirty-nine consecutive patients with symptomatic occlusion of the anterior circulation and failure of medical therapy underwent endovascular recanalization and were included in this retrospective study. Patient characteristics, atherosclerotic risk factors, successful recanalization rates, and angiographic data were collected., Results: Recanalization was successful in 37 cases (94.9%). The average residual stenosis immediately after intervention was 11.6 ± 4.3%. The patients who underwent balloon angioplasty alone had similar residual stenosis to those who also underwent stent placement (15.6 ± 7.3% vs. 9.0 ± 6.4%, P = 0.184). Intra- and perioperative complications occurred in three cases (7.69%). One patient (2.7%) developed severe in-stent restenosis with transient ischemic attack symptoms at 1-year follow-up., Conclusions: Endovascular recanalization is feasible for symptomatic occlusion of the anterior circulation lasting longer than 72 h. Recanalization provides a higher success rate when performed within 6 months of the qualifying event., Competing Interests: There are no conflicts of interest., (Copyright: © 2021 Brain Circulation.)

The outbreak of Coronavirus Disease 2019 (COVID-19) has become a severe global acute respiratory pandemic around the world in just a few months with an increasing number of infections and deaths. COVID-19 is a highly contagious and fatal disease. Almost everyone in the population is susceptible, and the incubation period is 1-14 days, mostly 3-7 days. The clinical symptoms of the COVID-19 are fever, dry cough and fatigue. Some patients are accompanied by symptoms such as nasal congestion, runny nose, sore throat, myalgia and diarrhea. Severe patients could even develop acute respiratory distress syndrome, septic shocks, metabolic acidosis and multifunctional organ failure, etc. Due to the relatively closed environment of dental clinics and the unique nature of dental procedures, both dental personnel and patients are easy to get infection through currently known respiratory droplet transmission, aerosol transmission, close contact transmission and other ways, inducing mutual cross-infection. Dental practitioners are facing unprecedented challenges due to the high risk of exposure to droplets and aerosols from saliva and other body fluids during dental procedures. Based on our experience and relevant research, this article introduces the basic knowledge about COVID-19 and the corresponding protective measures for dental practitioners, includes the risk of infection during dental procedures, the precautions related to the patients, infection control measures during dental treatment in clinics, protection measures at different levels for dental practitioners, and emergency dental treatment for confirmed COVID-19. It is the responsibility of every dental practitioner to fully understand the characteristics of the new coronavirus and strictly implement the most appropriate protective measures to reduce and control the risk of cross infection in dental procedures., (Copyright © 2020. Published by Elsevier Ltd.)

Aneurysms located in the posterior inferior cerebellar artery (PICA) are not a majority of the intracranial aneurysms cases. Many challenges were addressed in the endovascular procedure to treat the disease. The authors have successfully diagnosed and treated a ruptured proximal PICA aneurysm. However, digital subtraction angiography showed acute thrombosis in the vertebral artery in the procedure, which probably could be an acute in-stent thrombosis. The tirofiban hydrochloride injection was subjected through a microcatheter, and then, the second Neuroform EZ stent was planted. In the 6-month follow-up, no recurrence of the aneurysm and complete patency of the right PICA at the site of aneurysm formation were found. We believe that the treatment of PICA aneurysms with Neuroform EZ stents could get a favorable result. Combination of tirofiban hydrochloride and Neuroform EZ stent could be an effective approach in treating acute thrombotic complications., Competing Interests: There are no conflicts of interest., (Copyright: © 2020 Brain Circulation.)

Objectives: Symptomatic atherosclerotic disease of the basilar artery (BA) portends a poor prognosis, and BA seemed to be the most dangerous site for stenting. The authors review their interventional results and mid-term results with or without predilation in BA stenting to find a safer interventional approach., Patients and Method: A database review identified 94 patients with severe symptomatic BA stenosis were treated with stenting. According to with balloon predilation or not, they were divided into two groups: direct stenting group and angioplasty before stenting group. Baseline data, lesion characteristics, complications and follow-up data from the two groups were compared and analyzed., Results: The length of lesion in angioplasty before stenting group was longer than that in the direct stenting group (8.12 ± 2.76 mm versus 6.83 ± 2.27 mm, p = 0.015). The proportions of Mori C type lesion was higher in angioplasty before stenting group (31.3 % versus 8.7 %, p = 0.006). The residual stenosis was higher in angioplasty before stenting group (12.66 ± 9.24 % versus 7.67 ± 8.01 %, p = 0.006). There were no significant differences in TIA, stroke, and death between the two groups in the perioperative and postoperative > 1 year follow-up (p > 0.05)., Conclusion: BA stenting is relatively safe and has a good results for experienced operators. Angioplasty before stenting is a good way for BA stenting, it makes the operations on difficult lesions as safe as normal one. More optimized stents and safer interventional approach need to be further explored and verified., Competing Interests: Declaration of Competing Interest None., (Copyright © 2020 Elsevier B.V. All rights reserved.)

HDAC3 is an essential negative regulator of neuronal plasticity and memory formation. Although a chemical inhibitor has been invented, little is known about its endogenous modulators. We explored whether miR-494 affects HDAC3-mediated neuronal injury following acute ischemic stroke. A substantial increase in plasma miR-494 was detected in AIS patients and was positively associated with the mRS at one year after symptom onset. The miR-494 levels were transiently increased in the infarcted brain tissue of mice. In contrast, miR-494 levels were reduced in neurons but increased in the medium after OGD. Intracerebroventricular injection of miR-494 agomir reduced neuronal apoptosis and infarct volume at the acute stage of MCAO, promoted axonal plasticity and long-term outcomes at the recovery stage, suppressed neuronal ataxin-3 and HDAC3 expression and increased acetyl-H3K9 levels in the ipsilateral hemisphere. In vitro studies confirmed that miR-494 posttranslationally inhibited HDAC3 in neurons and prevented OGD-induced neuronal axonal injury. The HDAC3 inhibitor increased acetyl-H3K9 levels and reversed miR-494 antagomir-aggravated acute cerebral ischemic injury, as well as brain atrophy and long-term functional recovery. These results suggest that miR-494 may serve as a predictive biomarker of functional outcomes in AIS patients and a potential therapeutic target for the treatment of ischemic stroke.

The present study evaluated the diagnostic and predictive potential of microRNA-93 in acute ischemic stroke (AIS) patients within 6 h of stroke onset and its regulation on microglial inflammation in vitro. Our results showed that the miR-93 levels in plasma and neutrophil detected by real-time PCR were evidently reduced in AIS patients, and Pearson's correlation analysis showed that miR-93 levels in plasma and neutrophils had a significant positive linear correlation. Moreover, miR-93 levels in plasma and neutrophils of stroke patients at time of admission were not correlated with infarct volume and NIHSS (National Institute of Health stroke scale) scores at admission, but neutrophil miR-93 levels were positively correlated with the Barthel Index 7 days after stroke. Importantly, miR-93 levels in plasma and neutrophil of AIS patients were negatively correlated with the expression of TNF-α and IL-10. Furthermore, in vitro treatment with miR-93 agomir decreased the OGD (Oxygen and glucose deprivation)-induced proliferation of BV2 microglial cells tested by Flow cytometry. We demonstrated that miR-93 in blood has a potential to facilitate the diagnosis and prediction of neurological outcomes of acute ischemic stroke, and is involved in inflammation possibly through targeting the proliferation of microglia., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Objective: To compare the technical and 1-year clinical outcome in balloon-mounted versus self-expanding stenting for symptomatic severe stenosis of the middle cerebral artery combined with poor collaterals in China., Methods: Ninety-one patients with severe middle cerebral artery atherosclerotic stenosis combined with poor collaterals were recruited in the study. Balloon-mounted stent or self-expanding stent were selected to treat patients following a guideline. The baseline characteristics, cerebral angiography, and outcomes were compared between the patients treated with balloon-mounted stent and self-expanding stent., Results: The mean degree of stenosis was 85.5% ± 6.37% in the balloon-mounted stenting group and 85.4% ± 7.73% in the self-expanding stenting group before treatment (P = 0.930). A longer operative time occurred in patients treated with self-expanding stent than in those treated with balloon-mounted stent (96.7 vs. 68.6 minutes, respectively; P = 0.002). Patients with self-expanding stent had a higher rate of residual stenosis than those with balloon-mounted stent (67.3% vs. 38.9%, respectively; P = 0.014). The patients in balloon-mounted stenting group was less likely to have restenosis (6.1% vs. 26.5%, P = 0.019) and had a lower degree of stenosis (5.0% ± 0.0% vs. 26.9% ± 29.2%, P = 0.019) compared with patients in the self-expanding stenting group. During the 1-year follow-up, the recurrence rate of ischemic stroke, transient ischemic attack, hemorrhage stroke, and death was not significantly different between the 2 groups (1/33 vs. 2/49, P = 0.804; 1/33 vs. 1/49, P = 0.776; 0/33 vs. 2/49, P = 0.240; 1/33 vs. 0/49, P = 0.220, respectively)., Conclusions: Balloon-mounted stents may have a shorter operative time and lower restenosis occurrence than self-expanding stents. No significant difference in 1-year outcome was observed between the 2 groups., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The exchange proteins activated by cAMP (Epacs) have been shown to play important roles in producing inflammation-induced nociception. Transient receptor potential vanilloid type 1 (TRPV1) is a major receptor processing thermal and chemosensitive nociceptive information. The role of Epacs in modulating the activity of TRPV1 has yet to be determined. Studying the effect of complete Freund adjuvant (CFA)-induced inflammation on capsaicin-activated TRPV1 nociceptive responses in dorsal root ganglia (DRG), we found that CFA produced a large increase in capsaicin-induced responses. The increase was inhibited by Epac1 and Epac2 antagonists. Thus, activation of Epacs is critical in producing enhancement in TRPV1-mediated responses under inflammatory conditions. In addition, the inflammation-induced enhancement of TRPV1 responses was blocked by PKCα and PKCε inhibitors, suggesting the essential roles of these PKCs in enhancing TRPV1 responses. To determine the mechanism underlying the Epac actions on TRPV1, we studied the effects of the Epac activator, 8-(4-chlorophenylthio)-2-O-methyl-cAMP (CPT), on capsaicin-induced nociceptive behavioral responses, capsaicin-activated currents, expression and membrane trafficking of PKC and TRPV1 in DRG. CPT was found to enhance capsaicin-induced nociception and ionic currents. The enhancement was inhibited by PKCα and PKCε inhibitors. In addition, CPT increased the expression of phosphorylated PKCα (pPKCα) and membrane TRPV1 expression in DRG. Studying the colocalization of TRPV1 and pPKCα or pPKCε in DRG slices prepared from CFA-treated rats, we found that pPKCα or pPKCε expressed with TRPV1 in different-sized neurons to exert differential influences on TRPV1 activity. Thus, Epac-PKC signaling is critically important in producing inflammation-induced potentiation of TRPV1 functions.

Stroke is the number one cause of neurological dysfunction in adults and has a heavy socioeconomic burden worldwide. The etiological origins of ischemic stroke and resulting pathological processes are mediated by a multifaceted cascade of molecular mechanisms that are in part modulated by posttranscriptional activity. Accumulating evidence has revealed a role for microRNAs (miRNAs) as essential mediators of posttranscriptional gene silencing in both the physiology of brain development and pathology of ischemic stroke. In this review, we compile miRNAs that have been reported to regulate various stroke risk factors and pre-disease mechanisms, including hypertension, atherosclerosis, and diabetes, followed by an in-depth analysis of miRNAs in ischemic stroke pathogenesis, such as excitotoxicity, oxidative stress, inflammation, apoptosis, angiogenesis and neurogenesis. Since promoting or suppressing expression of miRNAs by specific pharmaceutical and non-pharmaceutical therapies may be beneficial to post-stroke recovery, we also highlight the potential therapeutic value of miRNAs in clinical settings., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The topography of biomaterials can significantly influence the osteogenic differentiation of cells. Understanding topographical signal transduction is critical for developing biofunctional surfaces, but the current knowledge is insufficient. Recently, numerous reports have suggested that the unfolded protein response (UPR) and osteogenic differentiation are inter-linked. Therefore, we hypothesize that the UPR pathway may be involved in the topography-induced osteogenesis. In the present study, different surface topographies were fabricated on pure titanium foils and the endoplasmic reticulum (ER) stress and UPR pathway were systematically investigated. We found that ER stress and the PERK-eIF2α-ATF4 pathway were activated in a time- and topography-dependent manner. Additionally, the activation of the PERK-eIF2α-ATF4 pathway by different topographies was in line with their osteogenic induction capability. More specifically, the osteogenic differentiation could be enhanced or weakened when the PERK-eIF2α-ATF4 pathway was promoted or inhibited, respectively. Furthermore, tuning of the degree of ER stress with different concentrations of thapsigargin revealed that mild ER stress promotes osteogenic differentiation, whereas excessive ER stress inhibits osteogenic differentiation and causes apoptosis. Taken together, our findings suggest that the UPR may play a critical role in topography-induced osteogenic differentiation, which may help to provide new insights into topographical signal transduction., Statement of Significance: Suitable implant surface topography can effectively improve bioactivity and eventual bone affinity. However, the mechanism of topographical signaling transduction is unclear and criteria for designation of an appropriate implant surface topography is lacking. This study shows that the ER stress and PERK-eIF2α-ATF4 pathway were activated by micro- and micro/nano-topographies, which is corresponding to the osteogenic induction abilities of these topographies. Furthermore, we have found that mild ER stress improves osteogenic differentiation, whereas excessive ER stress inhibits osteogenic differentiation and causes apoptosis. Our findings demonstrate that the UPR plays a critical role in the topography induced osteogenic differentiation, which may help to provide new insights into the topographical signaling transduction., (Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Micro/nano-textured titanium surface topography promotes osteoblast differentiation and the Wnt/β-catenin signaling pathway. However, the response of rat bone mesenchymal stem cells (MSCs) to micro/nano-textured topography, and the underlying mechanisms of its effects, are not well understood. We hypothesized that cell division cycle 42 protein (Cdc42), a key member of the Rho GTPases family, may regulate rat MSCs morphology and osteogenic differentiation by micro/nano-textured topography, and that crosstalk between Cdc42 and Wnt/β-catenin is the underlying mechanism. To confirm the hypothesis, we first tested rat MSCs' morphology, cytoskeleton, and osteogenic differentiation on micro/nano-textured topography. We then examined the cells' Wnt pathway and Cdc42 signaling activity. The results show that micro/nano-textured topography enhances MSCs' osteogenic differentiation. In addition, the cells' morphology and cytoskeletal reorganization were dramatically different on smooth surfaces and micropitted/nanotubular topography. Ligands of the canonical Wnt pathway, as well as accumulation of β-catenin in the nucleus, were up-regulated by micro/nano-textured topography. Cdc42 protein expression was markedly increased under these conditions; conversely, Cdc42 silencing significantly depressed the enhancement of MSCs osteogenic differentiation by micro/nano-textured topography. Moreover, Cdc42si attenuated p-GSK3β activation and resulted in β-catenin cytoplasmic degradation on the micro/nano-textured topography. Our results indicate that Cdc42 is a key modulator of rat MSCs morphology and cytoskeletal reorganization, and that crosstalk between Cdc42 and Wnt/β-catenin signaling though GSK3β regulates MSCs osteogenic differentiation by implant topographical cues., Statement of Significance: Topographical modification at micro- and nanoscale is widely applied to enhance the tissue integration properties of biomaterials. However, the response of bone mesenchymal stem cells (MSCs) to the micro/nano-textured topography and the underlying mechanisms are not well understood. This study shows that the micropitted/nanotubular hierarchical topography produced by etching and anodic oxidation treatment drives fusiform cell morphology, cytoskeletal reorganization as well as better MSCs osteogenic differentiation. The cross-talk between Cdc42 pathway and Wnt/β-catenin pathway though GSK3β modulates the osteoinductive effect of the micro/nano-textured topography on MSCs. This finding sheds light on a novel mechanism involved in micro/nano-textured surface-mediated MSCs osteogenic differentiation and is a major step in the development of new surface modifications aiming to accelerate and enhance the process of osseointegration., (Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Objectives: We have previously shown the neuroprotective function of microRNA-99a-5p in experimental stroke. Here, we explore its diagnostic potential for acute stroke patients., Materials and Methods: MiR-99a-5p levels in circulating from acute stroke patients and control were measured by real-time polymerase chain reaction. Pearson's correlation and receiver operator characteristic (ROC) curves were used to analyze clinical significance of miR-99a-5p and its sensitivity and specificity for stroke diagnosis., Results: We demonstrated that miR-99a-5p expression was upregulated in neutrophils of both ischemic stroke and hemorrhage patients, while was only increased in the lymphocytes of hemorrhage patients. ROC analysis revealed that the miR-99a-5p level in neutrophils and lymphocytes had a moderate diagnostic value for stroke. Moreover, a positive correlation existed between plasma miR-99a-5p levels and neutrophil numbers or neutrophil/lymphocyte ratio. Meanwhile, miR-99a-5p levels in neutrophils were negatively correlated with thrombin time, while positively correlated with D-dimer and urea levels. Lymphocytic miR-99a-5p levels were positively correlated with platelet mean volume and distribution width., Conclusion: This study demonstrated that miR-99a-5p levels in circulating immune cells might facilitate the diagnosis of ischemic stroke., Competing Interests: There are no conflicts of interest.

A novel label-free electrochemical biosensor for the detection of Hg 2+ based on ligase mediated creation of G-quadruplex-hemin DNAzyme has been developed. Firstly, Cp probe was immobilized on the gold electrode surface through Au-SH bond. In the presence of Hg 2+ , Cp and Ap probes were partly hybridized with the LJ probe respectively through the specific T-Hg 2+ -T interaction. Then, the adjacent 3'-OH terminal of Cp will link with the 5'-PO 4 terminal of Ap to form a G-rich DNA at the function of T4-ligase. After interaction with hemin, the G-rich DNA can form a G-quadruplex-hemin HRP-mimicking DNAzyme. Through measuring the current change caused by DNAzyme-catalyzed oxidation of 3,3',5,5'-tetramethylbenzidine(TMB), sensitive detection of Hg 2+ can be achieved. The proposed sensor is simple, sensitive and selective, without the need of complicated labeling process, thus holds great potential for routine analysis of Hg 2+ in environmental and biological samples., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: Evaluation of analgesics in large animals is a necessary step in the development of better pain medications or gene therapy prior to clinical trials. However, chronic neuropathic pain models in large animals are limited. To address this deficiency, we developed a neuropathic pain model in sheep, which shares many anatomical similarities in spine dimensions and cerebrospinal fluid volume as humans., Methods: A neuropathic pain state was induced in sheep by tight ligation and axotomy of the common peroneal nerve. The analgesic effect of intrathecal (IT) morphine was investigated. Interspecies comparison was conducted by analyzing the ceiling doses of IT morphine for humans, sheep, and rats., Results: Peroneal nerve injury (PNI) produced an 86% decrease in von-Frey filament-evoked withdrawal threshold on postsurgery day 3 and the decrease lasted for the 8-week test period. Compared to the pre-injury, sham, and contralateral hindlimb, the IT morphine dose that produces 50% of maximum analgesia (ED(50)) for injured PNI hindlimb was 1.8-fold larger and E(max), the dose that produces maximal analgesia, was 6.1-fold lower. The sheep model closely predicts human IT morphine ceiling dose by allometric scaling. This is in contrast to the approximately 10-fold lower morphine ceiling dose predicted by the rat spinal nerve ligated or spared nerve injury models., Conclusion: PNI sheep model has a fast onset and shows stable and long-lasting pain behavioral characteristics. Since the antinociceptive properties of IT morphine are similar to those observed in humans, the PNI sheep model will be a useful tool for the development of analgesics. Its large size and consistent chronic pain behavior will facilitate the development and evaluation of surgical intervention and gene therapy. The PNI sheep pain model provides us with the opportunity for multi-species testing, which will improve the success of clinical trials.

Scutellaria barbata D. Don is widely used as a folk antitumor and anti-inflammatory agent in Asia. However, a simple and global quality control method for S. barbata was lacking. In this study, six phenolic compounds, including P-coumaric acid, scutellarin, apigenin 5-O-β-glucopyranoside, luteolin, apigenin and 4'-hydroxywogonin were obtained from S. barbata by phytochemical investigations. The six compounds plus baicalein show cytotoxcities to the nine human cancer cells, K562, MGC-803, HL60, SH-SY5Y, SW1116, SMMC-7221, SW480, HepG2 and KB. Subsequently, a high-performance liquid chromatography with photodiode array detector (HPLC-DAD) was developed for both fingerprint analysis of S. barbata and quantitative determination of the seven anticancer active compounds in S. barbata. The chromatographic separation was accomplished on an Ultimate™ XB-C18 column (4.6 x 250 mm, 5 µm) in 65 min. For fingerprinting, 26 common peaks were found and selected as characteristic peaks to assess the consistency of S. barbata samples. For quantitative analysis, the seven bioactive compounds showed good regression relationship ( R² > 0.999) within test ranges and the recovery of the method was in the range of 90-105 %. In brief, the present study provides the fingerprint analysis and quantitative methods for global and systematical quality control of S. barbata for its anticancer usage., (© Georg Thieme Verlag KG Stuttgart · New York.)