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Abstract Implantable neural probes, essential for brain electrophysiological research, have advanced with ultra-flexible designs to mitigate immune responses and postoperative complications. Strategies of shuttle-assisted implantation and temporary stiffening address issues in penetrating these probes into the target region, avoiding undesired bending. However, the risk of intraoperative bleeding remains due to these implants’ necessary rigidity during insertion. Here, we describe a neural probe with mechanical compliance accompanying self-implantation along the principal axis in the absence of bleeding. Crucial to the behavior is its anisotropic relaxation, which is dominated by the cross-sectional in-plane deformation inhibition due to interchain interactions between the parallel backbones in the globally aligned polymer system. We observed the ensured upright insertion of the probe into the brain while avoiding angiorrhexis with a two-photon microscope and a high-speed camera. The probes permit electrophysiological studies with minimal foreign body responses and imageological compatibility, underscoring their clinical potential.

Introduction Endoscopic submucosal dissection (ESD) is the first choice for superficial tumor resection. There is no report on whether the training effect is affected by limiting the operation time of each ESD operation. This study aimed to prospectively evaluate the efficiency of time-limited ESD training by using an ex vivo porcine stomach model.

Abstract In this study, a gold nanoparticles colorimetric probe (AuNPs) with direct response to mercury ions (Hg2+) were developed using treated N-methylpyrrolidone (NMP) and chloroauric acid (HAuCl4) as precursors. NMP showed good reducibility after high temperature hydrolysis and could be used as reducing and stabilizing agent to synthesize AuNPs. The prepared AuNPs have obvious characteristic absorption peaks and appear wine-red. At the same time, it was found that the presence of Hg2+ can cause the aggregation of AuNPs, increased the absorbance at 700 nm, and changed the color of the solution into blue-gray. This method is capable of sensitive and specific determination of Hg2+ ranging from 1 to 30 μM, with the limit of detection (LOD) at 0.3 μM. The method showed good specificity for the determination of Hg2+ and has the potential to be applied to Hg2+ detection in sewage samples in the environment.

Acute portal vein thrombosis (PVST), a serious complication of liver cirrhosis, is characterized as abdominal pain secondary to intestinal ischemia, and even intestinal necrosis. Anticoagulation is recommended for the treatment of acute PVST, but is often postponed in cirrhotic patients with acute variceal bleeding or those at a high risk of variceal bleeding. Herein, we reported a 63-year-old male with a 14-year history of alcoholic liver cirrhosis who developed progressive abdominal pain related to acute portal vein and superior mesenteric vein thrombosis immediately after endoscopic variceal ligation combined with endoscopic cyanoacrylate glue injection for acute variceal bleeding. Fortunately, acute PVST was successfully recanalized by the use of low molecular weight heparin. Collectively, this case suggests that acute symptomatic PVST can be secondary to endoscopic variceal therapy in liver cirrhosis, and can be safely and successfully treated by anticoagulation.

Abstract Fertilization can be optimized and managed during the flue-cured tobacco growing period by studying the response of soil and microbial biomass stoichiometric characteristics to fertilization. In this study, we investigated the effect of compound fertilizers combined with microbial fertilizer treatments on the stoichiometric characteristics of the rhizosphere soil and the limitations of microbial resources during the flue-cured tobacco growing period. The results indicated that soil and microbial C:N:P varied greatly with the growing period. The effect of sampling time was usually greater than that of fertilization treatment, and microbial C:N:P did not vary with the soil resource stoichiometric ratio. The microbial metabolism of the tobacco-growing soil was limited by phosphorus after extending the growing period, and phosphorus limitation gradually increased from the root extension to the maturation periods but decreased at harvest. The rhizosphere soil microbial nitrogen and phosphorus limitations were mainly affected by soil water content, soil pH, microbial biomass carbon, and the ratio of microbial biomass carbon to microbial biomass phosphorus. Applying microbial fertilizer reduced phosphorus limitation. Therefore, applying microbial fertilizer regulated the limitation of microbial resources by affecting the soil and microbial biomass C:N:P in flue-cured tobacco rhizosphere soils.

Abstract Background The optimal timing of endoscopy in liver cirrhosis with acute variceal bleeding (AVB) remains controversial in current guidelines and studies. Methods Consecutive patients with liver cirrhosis and AVB were screened. The timing of endoscopy was calculated from the last presentation of AVB or the admission to endoscopy. Early endoscopy was defined as the interval

Formaldehyde (FA) is widely used in industry and also common in daily life. Finding an efficient method to determine FA is quite an industrial challenge. Herein, a novel method based on a resonance light scattering (RLS) technique was developed for the detection of FA with high sensitivity. Carbon dots (CDs) were used as RLS probes. CDs were obtained via one-pot solvothermal treatment from o-phenylenediamine. CDs showed yellow fluorescence with a quantum yield of 0.41. Due to the multiple amino groups on the surface of CDs, FA can be captured easily by formation of a covalent C = N bond based on the Schiff-base reaction. Owing to the covalent crosslinking, CD nanoparticles aggregated, and even formed precipitate. The aggregation of CDs induced RLS enhancement, where the RLS increment was linearly related to the concentration of FA ranging from 4 nM to 1.6 mM, with a limit of detection (LOD) of 1.6 nM. In comparison with many previous reports, the present RLS method showed a wider linear range and lower LOD. Furthermore, the RLS system was successfully used to detect FA in real food samples. The proposed system has prospective applicability in the detection of FA in food fields.

In this study, a portable silver ion (Ag+) sensor was fabricated based on a dual signal output system using black phosphorus quantum dots (BPQDs) as probes. It is the first work for Ag+ detection using paper test strip based on BPQDs. The color change of BPQDs paper sensor for the determination of Ag+ was easily identified by naked eye. BPQDs were synthesized from bulk black phosphorus (BP) by mechanical exfoliation combined with a solvothermal method. BPQDs exhibited blue fluorescence with a quantum yield of 8.82 %. The fluorescence of BPQDs can be quenched by Ag+, and the absorbance of BPQDs is increased with increasing Ag+ concentration. The mechanism of the interaction between BPQDs and Ag+ involving fluorescence quenching and bonding was investigated by experimental and computational methods. The detection limit of Ag+ was 1.56 μg/mL and 0.19 μg/mL using fluorometry and colorimetry methods, respectively. A portable visual sensor based on paper test strip was constructed for Ag+ detection using the colorimetric approach. The strategy was employed to determine Ag+ successfully in drinking water samples. Therefore, the proposed portable Ag+ sensor can be potentially utilized for the lab-free analysis of drinking water and even dietary samples.

We report a 1.04 GHz high-power Kerr-lens mode-locked Yb:CaYAlO4 laser pumped by a single-mode fiber laser at 976 nm. Based on a bow-tie cavity, stable unidirectional mode-locked operation is obtained with an output coupler of 1.6%. The oscillator delivers pulses with an average power of 1.46 W and with the pulse duration of 99 fs, which, to the best of our knowledge, is the first gigahertz-level Kerr-lens mode-locked laser based on the Yb:CaYAlO4 gain medium. We believe that the watt-level solid-state femtosecond laser at GHz would be an excellent source for developing time-resolved broadband dual-comb spectroscopy.

While single, dispersed atoms enable efficient atomic utilization, controllably preparing single-atom dimers remains challenging. Here, authors prepare nickel-cobalt single-atom dimers as high-performance pH-universal H2 evolution electrocatalysts.

The poor catalyst stability for oxygen evolution in acidic media has been a long-time issue. Here, authors demonstrate iridium on MoO3 exhibits a low overpotential for oxygen evolution and excellent durability in acidic media due to the high oxidation state of iridium metal on MoO3.

We experimentally explored the relationship between the pump power fixed point and the net-cavity dispersion in a Yb-fiber optical frequency comb. By continuously adjusting the distance of the grating pair in the Yb-fiber oscillator, we measured the pump power fixed point frequency in different dispersion regimes and different intracavity polarization states. We find that the fixed point frequency for pump power is not always near the carrier frequency but changes significantly with the net-cavity dispersion and polarization. Especially at the near zero-dispersion point, the fixed point has a local minimum, which is less than tens of THz and far lower than the carrier frequency. This is the first time to completely reveal the influence of net-cavity dispersion and intracavity polarization state on the fixed point in the experiment.

Background: The association of endoscopic variceal treatment (EVT) with portal venous system thrombosis (PVST) in liver cirrhosis is still unclear. Methods: PVST was assessed by contrast-enhanced CT or MRI in 406 cirrhotic patients from our prospective database. Case and control groups, which are defined as patients with and without PVST, respectively, were matched at a ratio of 1:1 according to age, gender, Child-Pugh class, and MELD score. History of EVT was reviewed. Logistic regression analysis was used to identify the risk factors for PVST. Odds ratios (ORs) were calculated. Subgroup analyses were further performed in terms of degree and location of PVST. Results: Overall, 109 patients each were included in case and control groups. The case group had a significantly higher proportion of patients who had undergone EVT than the control group (53.2% versus 18.3%; p

Gastric antral vascular ectasia (GAVE) is one of the uncommon causes of upper gastrointestinal bleeding. Major treatment of GAVE includes pharmacotherapy, endoscopy, and surgery. The efficacy and safety of pharmacotherapy have not been sufficiently confirmed; and surgery is just considered when conservative treatment is ineffective. By comparison, endoscopy is a common treatment option for GAVE. This paper reviews the currently used endoscopic approaches for GAVE, mainly including argon plasma coagulation (APC), radiofrequency ablation (RFA), and endoscopic band ligation (EBL). It also summarizes their efficacy and procedure-related adverse events. The endoscopic success rate of APC is 40–100%; however, APC needs several treatment sessions, with a high recurrence rate of 10–78.9%. The endoscopic success rates of RFA and EBL are 90–100% and 77.8–100%, respectively; and their recurrence rates are 21.4–33.3% and 8.3–48.1%, respectively. Hyperplastic gastric polyps and sepsis are major adverse events of APC and RFA; and Mallory–Weiss syndrome is occasionally observed after APC. Adverse events of EBL are rare and mild, such as nausea, vomiting, esophageal or abdominal pain, and hyperplastic polyps. APC is often considered as the first-line choice of endoscopic treatment for GAVE. RFA and EBL have been increasingly used as alternatives in patients with refractory GAVE. A high recurrence of GAVE after endoscopic treatment should be fully recognized and cautiously managed by follow-up endoscopy. In future, a head-to-head comparison of different endoscopic approaches for GAVE is warranted.

Background and Aims. Left-sided portal hypertension (LSPH) is a rare type of portal hypertension, which occurs due to obstruction, stenosis, or thrombosis within the splenic vein. Pancreatic diseases are the most common etiology of LSPH. This study is aimed at reporting our experiences and discussing the presentation, management, and prognosis of LSPH secondary to pancreatic diseases. Patients and Methods. We retrospectively reviewed five patients who were diagnosed with LSPH secondary to pancreatic diseases at our department. We collected the demographic information, history, comorbidities, clinical presentations, laboratory tests, esophagogastroduodenoscopy (EGD), images, and outcome data. Results. Three elderly patients (>60 years old) were diagnosed with pancreatic cancer, of whom one underwent laparoscopic radical distal pancreatectomy and splenectomy, one received chemotherapy, and another one chose conservative management due to multiple systemic metastases. Two younger patients (

Based on the advantages of the topology optimization method, a new mini-channel heat sink with arc-type design domain topology design is proposed in this work. This arc-type design domain is used to realize the flow distribution uniformity. Two dual objective optimization functions were selected to complete the topology design, and two topology optimization mini-channel models M1 and M2 were obtained. The aim of M1 is to achieve minimum average temperature and fluid dissipation of the heat source area. The fluid dissipation was used to characterize the pressure drop characteristics. The aim of M2 is to achieve minimum temperature difference and fluid dissipation of the heat source area. Then, the fluid and heat transfer characteristics of M1, M2, and the traditional straight heat sink M3 were analyzed by numerical simulation. Compared with straight mini-channel heat sink M3, the temperature differences of the mini-channel heat sink designed M1 and the mini-channel heat sink designed M2 were decreased by 31.6% and 42.48%, respectively. Compared with M3, the pressure drops of M1 and M2 were decreased by 22.7% and 30.9%, respectively. Moreover, the Nusselt number of the mini-channel heat sink designed M1 was increased by 34.43%. In comparison, that of the mini-channel heat sink-designed M2 increased by 15.86%. The thermal performance evaluation criteria (PEC) showed that the PEC value of M1 was greater than 1.4, while the PEC value of M2 was less than 1.14. Finally, experiments were conducted for M1 to verify the accuracy of the numerical simulation. It was found that the simulation results agreed well with the experimental results.

Background: MiR-134 is enriched in dendrites of hippocampal neurons and plays crucial roles in the progress of epilepsy. The present study aims to investigate the effects of antagomirs targeting miroRNA-134 (Ant-134) on limk1 expression and the binding of miR-134 and limk1 in experimental seizure. Methods: Status epilepticus (SE) rat model was established by lithium chloride-pilocarpine injection and was treated with Ant-134 by intracerebroventricular injection. Low Mg2+-exposed primary neurons were used as an in vitro model of SE. The expression of miR-134 was determined using real-time PCR. Protein expressions of limk1 and cofilin were determined by Western blotting. Luciferase reporter assay was used to examine the binding between miR-134 and limk1 3’-untranslated region. Results: The expression of miR-134 was markedly enhanced in hippocampus of the SE rats and low Mg2+-exposed neurons. Ant-134 increased the expression of limk1 and reduced the expression of cofilin in the SE hippocampus and Low Mg2+-exposed neurons. In addition, luciferase reporter assay confirmed that miR-134 bound limk1 3’-UTR. MiR-134 overexpression inhibited limk1 mRNA and protein expressions in neurons. Conclusion: Blockage of miR-134 upregulates limk1 expression and downregulated cofilin expression in hippocampus of the SE rats. This mechanism may contribute to the neuroprotective effects of Ant-134.

Nonselective β blockers (NSBBs) combined with esophageal variceal ligation (EVL) are recommended for secondary prophylaxis of esophageal variceal bleeding (EVB) in cirrhotic patients according to the current practice guidelines and consensus. However, until now, there is a paucity of recommendations regarding the use of NSBBs in cirrhotic patients who achieved variceal eradication. In this review paper, we firstly introduced a case who achieved variceal eradication after additional use of NSBBs for secondary prophylaxis of EVB and then did not require further endoscopic therapy during repeated endoscopic surveillance, and subsequently discuss the importance of NSBBs for secondary prophylaxis of EVB, the effect of NSBBs after variceal eradication, adherence to NSBBs, screening for variceal recurrence, and timing of endoscopic surveillance after variceal eradication.

Background and Aims. Liver fibrosis blood tests, platelet count/spleen diameter ratio (PSR), and contrast-enhanced CT are diagnostic alternatives for gastroesophageal varices, but they have heterogeneous diagnostic performance among different study populations. Our study is aimed at evaluating their diagnostic accuracy for esophageal varices (EVs) and gastric varices (GVs) in cirrhotic patients with and without previous endoscopic variceal therapy. Methods. Patients with liver cirrhosis who underwent blood tests and contrast-enhanced CT scans as well as endoscopic surveillance should be potentially eligible. EVs needing treatment (EVNTs) and GVs needing treatment (GVNTs) were recorded according to the endoscopic results. Area under the curves (AUCs) were calculated. Results. Overall, 279 patients were included. In 175 patients without previous endoscopic variceal therapy, including primary prophylaxis population (n=70), acute bleeding population (n=38), and previous bleeding population (n=67), the diagnostic accuracy of contrast-enhanced CT for EVNTs was higher (AUCs=0.816‐0.876) as compared to blood tests and PSR; by comparison, the diagnostic accuracy of contrast-enhanced CT for GVNTs was statistically significant among primary prophylaxis population (AUC=0.731, P=0.0316), but not acute or previous bleeding population. In 104 patients with previous endoscopic variceal therapy (i.e., secondary prophylaxis population), contrast-enhanced CT was the only statistically significant alternative for diagnosing EVNTs and GVNTs but with modest accuracy (AUCs=0.673 and 0.661, respectively). Conclusions. Contrast-enhanced CT might be a diagnostic alternative for EVNTs in cirrhotic patients, but its diagnostic performance was slightly weakened in secondary prophylaxis population. Additionally, contrast-enhanced CT may be considered for diagnosis of GVNTs in primary prophylaxis population without previous endoscopic variceal therapy and secondary prophylaxis population.

The essence of the 2030 Agenda for Sustainable Development adopted by the United Nations is described in 17 Sustainable Development Goals (SDGs). SDG 15 focuses on Life on Land, in other words, terrestrial biodiversity and ecosystems, as well as their services. Land degradation is a severe anthropic and natural phenomenon that is affecting land use/cover globally; therefore, a dedicated target of the SDG 15 (the indicator 15.3.1) was proposed. The identification of the areas where land degradation has occurred and the analysis of its drivers allow for the design of solutions to prevent further degradation in the studied areas. We followed the methodology proposed by the United Nations Convention to Combat Desertification (UNCCD) to study the land degradation in the Honghe Prefecture in southwest China between 2005 and 2015. Through spatial analysis, we found that the degraded areas were consistent with the areas of active human activities (such as urban centers), while the impact of natural factors (such as disasters) on land degradation existed in small areas at high altitudes. Land degradation was affected primarily by the loss of land productivity and secondly by land cover changes caused by the growth of artificial areas. Changes in the soil organic carbon were not significant. We concluded that human activity was the main driver of land degradation in Honghe Prefecture. Decision makers should work to find a balance between economic development and environmental protection to restore degraded land and strive to achieve a land degradation-neutral prefecture to defend all ecosystem services.

Peutz-Jeghers syndrome (PJS) is characterized by scattered black pigmentations on fingers and lips and multiple polyps in the gastrointestinal tract. Patients with PJS often have severe complications secondary to multiple large polyps. Herein, we present a young woman complicated with a large polyp in her colon without any clinical symptoms. We also emphasized the necessity of early diagnosis and treatment of multiple polyps in such patients.

The process parameters of selective laser melting (SLM) significantly influence molten pool formation. A comprehensive understanding and analysis, from a macroscopic viewpoint, of the mechanisms underlying these technological parameters and how they affect the evolution of molten pools are presently lacking. In this study, we established a dynamic finite element simulation method for the process of molten pool formation by SLM using a dynamic moving heat source. The molten pool was generated, and the dynamic growth process of the molten pool belt and the evolution process of the thermal field of the SLM molten pool were simulated. Then, a deposition experiment that implemented a new measurement method for online monitoring involving laser supplementary light was conducted using the same process parameters as the simulation, in which high-speed images of the molten pool were acquired, including images of the pool surface and cross-section images of the deposited samples. The obtained experimental results show a good agreement with the simulation results, demonstrating the effectiveness of the proposed algorithm.

The effects of the existing anti-epileptic drugs are unsatisfactory to almost one third of epileptic patients. MiR-134 antagomirs prevent pilocarpine-induced status epilepticus. In this study, a lithium chloride-pilocarpine-induced status epilepticus model was established and treated with intracerebroventricular injection of antagomirs targeting miR-134 (Ant-134). The Ant-134 treatment significantly improved the performance of rats in Morris water maze tests, inhibited mossy fiber sprouting in the dentate gyrus, and increased the survival neurons in the hippocampal CA1 region. Silencing of miR-134 remarkably decreased malonaldehyde and 4-hydroxynonenal levels and increased superoxide dismutase activity in the hippocampus. The Ant-134 treatment also significantly increased the production of ATP and the activities of mitochondrial respiratory enzyme complexes and significantly decreased the reactive oxygen species generation in the hippocampus compared with the status epilepticus rats. Finally, the Ant-134 treatment remarkably downregulated the hippocampal expressions of autophagy-associated proteins Atg5, beclin-1 and light chain 3B. In conclusion, Ant-134 attenuates epilepsy via inhibiting oxidative stress, improving mitochondrial functions and regulating autophagy in the hippocampus.

Selective laser melting (SLM) constitutes an additive manufacturing (AM) method. Many issues such as thermal strain and macro-thermal deformation, which are caused by the thermal stress of different process parameters, are not clear. In this paper, an efficient and fast manufacturing simulation method was researched based on a moving heat source model and an elastoplastic theory of welding simulation, which was studied based on the thermodynamic coupling algorithm with a software-developed application for the SLM process. Subsequently, typical case results of thin and hollow plate part formation and the corresponding performances were simulated in detail. The results demonstrated that the effective thermal stress increased as the layer height increased from the surface layer to the substrate, while the thermal strain followed an approximate change rule. In addition, the stress was released from the underlying substrate when the support was removed. Moreover, the largest single axis plane stress was changed from tension to compression from the edge to the center, finally reaching equilibrium. In particular, maximum macro thermal deformation occurred at the printed support structure to the samples, displaying similar results in other locations such as the corners. Finally, the effectiveness of the simulation could be verified from the realistic printed part, which could provide proof for the quality prediction of the part that is actually forming.

To determine the permeability properties of lining materials for the design of nonmetallic pipes in oil and gas fields, we conducted a study on the transport behavior of pure and mixed gases (carbon dioxide [CO2] / methane [CH4]) through commonly used thermoplastic-lined pipe materials. The material tested were high-density polyethylene (HDPE), polyamide (PA), and polyvinylidene fluoride (PVDF). It was observed that the permeability coefficient of the pure gas through HDPE, PA12, and PVDF increased with increasing temperature. The permeation of mixed gas with different volume fractions was also tested at different temperatures, in which the deviation between the test and the ideal state was founded. For HDPE and PVDF, the permeability coefficient of the mixed gas is higher than that of pure gas because of the plasticization effect of CO2. However, for PA12, the permeability coefficient of mixed gas is lower than that of the pure gas. This is because of the tight interaction between the chains and the competition between CO2 and CH4 for a limited number of active sites. [ABSTRACT FROM AUTHOR]

Background/Aim: Gliomas are the most prevalent brain tumors with metabolic alterations playing a pivotal role in disease progression. However, the precise coordination of metabolic alterations with tumor-promoting cellular mechanisms, leading to tumor initiation, progression, and aggressiveness, resulting in poor outcomes, remains poorly understood in gliomas. Materials and Methods: We conducted a metabolism-targeted differential gene expression analysis using glioma patients' expression profiling data from The Cancer Genome Atlas (TCGA) database. In addition, pathway enrichment analysis, gene set enrichment analysis (GSEA), transcription factor prediction, network construction, and correlation analyses were performed. Survival analyses were performed in R. All results were validated using independent GEO expression datasets. Results: Metabolism-targeted analysis identified 5 hits involved in diverse metabolic processes linking them to disease aggressiveness in gliomas. Subsequently, we established that cell cycle progression and hyper-proliferation are key drivers of tumor progression and aggressiveness in gliomas. One of the identified metabolic hits, DNA primase 2 (PRIM2), a gene involved in DNA replication was found directly associated with cell cycle progression in gliomas. Furthermore, our analysis indicated that PRIM2, along with other cell cycle-related genes, is under the control of and regulated by the oncogenic MYC transcription factor in gliomas. In addition, PRIM2 expression alone is enough to predict MYC-driven cell cycle progression and is associated with tumor progression, aggressive disease state, and poor survival in glioma patients. Conclusion: Our findings highlight PRIM2 as a marker of MYC-driven cell cycle progression and hyper-proliferation, disease onset and progression, tumor aggressiveness, and poor survival in glioma patients. [ABSTRACT FROM AUTHOR]

Convection-enhanced delivery (CED) delivers agents directly into tumors and the surrounding parenchyma. Although a promising concept, clinical applications are often hampered by insufficient treatment efficacy. Toward developing an effective CED-based strategy for delivering drugs with proven clinical efficacy, we performed a basic characterization study to explore the locally delivered characteristics of the water soluble nitrosourea nimustine hydrochloride (ACNU). First, ACNU distribution after CED in rodent brain was studied using mass spectrometry imaging. Clearance of 14C-labeled ACNU after CED in striatum was also studied. ACNU was robustly distributed in rodent brain similar to the distribution of the hydrophilic dye Evans blue after CED, and locally delivered ACNU was observed for over 24 h at the delivery site. Subsequently, to investigate the potential of ACNU to induce an immunostimulative microenvironment, Fas and transforming growth factor-β1 (TGF-β1) was assessed in vitro. We found that ACNU significantly inhibited TGF-β1 secretion and reduced Fas expression. Further, after CED of ACNU in 9L-derived intracranial tumors, the infiltration of CD4/CD8 lymphocytes in tumors was evaluated by immunofluorescence. CED of ACNU in xenografted intracranial tumors induced tumor infiltration of CD4/ CD8 lymphocytes. ACNU has a robust distribution in rodent brain by CED, and delayed clearance of the drug was observed at the local infusion site. Further, local delivery of ACNU affects the tumor microenvironment and induces immune cell migration in tumor. These characteristics make ACNU a promising agent for CED. [ABSTRACT FROM AUTHOR]