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Introduction The contribution of neuroinflammation in cognitive impairment is increasingly recognized. Non-steroidal anti-inflammatory drugs had been proven that it could improve cognitive impairment in large dose but with more side effect, which limited the application. The main objective of this study was to investigate whether the combined use of nicotine and celecoxib could obtain synergistic neuroprotective effect in ischemic rats. Methods Twenty adult Sprague-Dawley (SD) rats underwent ischemic model surgery by injecting endothelin-1 into the left thalamus, which were classified into four groups with different interventions: nicotine (1.5 mg/kg/d), celecoxib (15 mg/kg/d), nicotine (1.5 mg/kg/d) +celecoxib (15 mg/kg/d), or saline after surgery. The other five SD rats also underwent same surgery by injecting saline instead of endothelin-1, as the control group. Morris water maze (MWM) test was adopted to assess the cognition. Micro PET/CT with 2-[18F]-A-85380 were performed for α4β2-nAChRs detection in vivo. Western blot, real-time PCR and immunohistochemical staining were adopted to detect the expression of α4β2-nAChRs and inflammatory factors which included TNF-α, IL-1β, IL-6 in brain tissue. Microglial activation in the brain was monitored by immunofluorescence with IBA1 staining. Results The MWM test showed rats given with nicotine or celecoxib alone showed much better memory than rats with saline, no difference was observed between nicotine and celecoxib. The rat memory was recovered most significant when the nicotine and celecoxib were combined (p Conclusions The study revealed the combined use of nicotine and celecoxib may improve the cognitive function in ischemic rats, with a better effect than either alone. Both nicotine and celecoxib can inhibit inflammation, but through different mechanisms: nicotine can activate α4β2-nAChRs while celecoxib is cyclooxygenase-2 inhibitor. Our findings suggest the combined application of two drugs with different anti-inflammation mechanism could attenuate cognitive impairment more effectively in ischemic rats, which may hold therapeutic potential in the clinical practice.

Electrochemiluminescence (ECL) is a process in which luminescence is produced by oxidizing or reducing luminophores to transfer radiant charges between electrochemically generated free radicals. Although about 7000 electrochemiluminescence articles have been published in the past 20 years (2000-2021), only a few review articles have summarized the development and application of ECL. In order to better understand the development status, research hotspots and future development trends of ECL technology, it is very necessary to conduct a comprehensive retrospective analysis. This review is based on the bibliometric analysis method of CiteSpace software to quantitatively analyze, visually review and comment on the articles published in the field of ECL in the past 20 years. Quantitatively analyze the authors, the institutional and other basic information to understand the basic development status of ECL, and then visually analyze the high-frequency keywords, burst keywords, keyword clusters, etc., to understand each the evolution of the main research hotspots and development directions of the period, and finally a detailed review and analysis of the selected highly cited articles. We particularly emphasized the development needs of electrochemiluminescence technology in improving the performance of ECL sensors, developing materials with excellent ECL performance, innovating and cooperating with other devices, and developing high-speed and high-throughput ECL sensors. We hope to provide new ideas for promoting the industrial development and clinical application of electrochemiluminescence technology.

Medium-low speed maglev, as a more comfortable type of medium volume urban rail transit system, has its own advantages. As the core entity carrying passengers, the acceleration and deceleration performance of maglev train undoubtedly has an important impact on the performance of the whole medium-low speed maglev system. The speed curve characteristics of the train under different operation conditions are the important design basis of the operation control system (OCS). Therefore, it is of great significance to study the accurate acceleration and deceleration performance of medium-low speed maglev train for improving the design of OCS and even the whole medium-low speed maglev system. Till now, most scholars have just focused on train speed profile optimization, and there are seldom considerations about the accuracy of the original train speed profile. In this paper, a fitting algorithm for speed performance curve of medium-low speed maglev train employing on-site testing operation data has been proposed, and based on Kalman filtering, the train speed curve with high confidence level under different working conditions can be precisely fitted.

Mechanical properties play key roles in the immune system, especially the activation, transformation and subsequent effector responses of immune cells. As transmembrane adhesion receptors, integrins mediate the adhesion events of both cells and cell-extracellular matrix (ECM). Integrin affinity would influence the crosslinking of cytoskeleton, leading to the change of elastic properties of cells. In this study, the cells were treated with F-actin destabilizing agent Cytochalasin-D (Cyt-D), fixed by Glutaraldehyde, and cultivated in hypotonic solution respectively. We used Atomic force microscopy (AFM) to quantitatively measure the elasticity of Jurkat cells and adhesion properties between integrins and vascular cell adhesion molecule-1 (VCAM-1), and immunofluorescence to study the alteration of cytoskeleton. Glutaraldehyde had a positive effect on the adhesion force and Young's modulus. However, these mechanical properties decreased in a hypotonic environment, confirming the findings of cellular physiological structure. There was no significant difference in the bond strength and elasticity of Jurkat cells treated with Cytochalasin-D, probably because of lower importance of actin in suspension cells. All the treatments in this study pose a negative effect on the adhesion probability between integrins and VCAM-1, which demonstrates the effect of structural alteration of the cytoskeleton on the conformation of integrin. Clear consistency between adhesion force of integrin/VCAM-1 bond and Young's modulus of Jurkat cells was shown. Our results further demonstrated the relationship between cytoskeleton and integrin-ligand by mechanical characteristics.

Nanomedicine has shown remarkable progress in preclinical studies of tumor treatment. Over the past decade, scientists have developed various nanocarriers (NCs) for delivering drugs into the tumor area. However, the average amount of accumulated drugs in tumor sites is far from satisfactory. This limitation is strongly related to the corona formation during blood circulation. To overcome this issue, NCs should be designed to become highly stealthy by modifying their surface charge. However, at the same time, stealthy effects not only prevent protein formation but also alleviate the cellular uptake of NCs. Therefore, it is necessary to develop NCs with switchable properties, which are stealthy in the circulation system and sticky when arriving at tumor sites. In this review, we discuss the recent strategies to develop passive and active charge-switchable NCs, known as chameleon-like drug delivery systems, which can reversibly transform their surface from stealthy to sticky and have various designs.

Decellularization method based on trypsin-digestion is widely used to construct small diameter vascular grafts. However, this method will reduce the opening angle of the blood vessel and result in the reduction of residual stress. Residual stress reduced has an adverse effect on the compliance and permeability of small diameter vascular grafts. To improve the situation, acellular blood vessels were treated with glutaraldehyde and photooxidation crosslinking respectively, and the changes of opening angle, circumferential residual strain of native blood vessels, decellularized arteries and crosslinked blood vessels were measured by means of histological examination, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) in this study. The opening angle of decellularized arteries significantly restored after photooxidation crosslinking (P = 0.0216), while that of glutaraldehyde crosslinking blood vessels reduced. The elastic fibers inside the blood vessels became densely rearranged after photooxidation crosslinking. The results of finite element simulation showed that the residual stress increased with the increase of opening angle. In this study, we found at the first time that photooxidation crosslinking method could significantly increase the residual stress of decellularized vessels, which provides biomechanical support for the development of new biomaterials of vascular grafts.

Bacterial biofilms caused by antibiotic resistance are a severe cause of infection threatening human health nowadays. The primary causes of this emerging threat are poor penetration of conventional antibiotics and the growing number of varied strains of resistant bacteria. Recently, bulk phytochemical oils have been widely explored for their potential as antibacterial agents. However, due to their poor solubility, low stability, and highly volatile properties, essential oils are not effective for in vitro and in vivo antibacterial applications and require further preparation. In this review, we discuss the recent progress and strategies to overcome the drawbacks of bulk phytochemical oils using nano-delivery, as well as the current challenges and future outlook of these nano-delivery systems against bacterial resistance.

A higher level of food safety is required due to the fast-growing human population along with the increased awareness of healthy lifestyles. Currently, a large percentage of food is spoiled during storage and processing due to enzymes and microbial activity, causing huge economic losses to both producers and consumers. Atomic force microscopy (AFM), as a powerful scanning probe microscopy, has been successfully and widely used in food preservation research. This technique allows a non-invasive examination of food products, providing high-resolution images of surface structure and individual polymers as well as the physical properties and adhesion of single molecules. In this paper, detailed applications of AFM in food preservation are reviewed. AFM has been used to provide comprehensive information in food preservation by evaluating the spoilage with its related structure modification. By utilizing AFM imaging and force measurement function, the main mechanisms involved in the loss of food quality and preservation technologies development can be further elucidated. It is also capable of exploring the activities of enzymes and microbes in influencing the quality of food products during storage. AFM provides comprehensive solutions to overcome spoilage issues with its versatile functions and high-throughput outcomes. Further research and development of this novel technique in order to solve integrated problems in food preservation are necessary.

Chinese data on the efficacy of low- and high-dose radioiodine for thyroid remnant are still absent. The aim of the study was to investigate whether a low dose of radioiodine is as effective as a high dose for remnant ablation in Chinese patients.Patients presenting for radioiodine ablation in the authors' department were included. Inclusion criteria were aged ≥16 years, total or near-total thyroidectomy, tumor-node-metastasis (TNM) stage of pT1-3, any N stage, and M0. All patients were randomly allocated to either the high-dose group of 3700 MBq or the low-dose group of 1850 MBq for remnant ablation. The response to treatment was defined as successful or unsuccessful after a six- to nine-month interval. Ablation was considered to be successful if patients fulfilled the following criteria: no tracer uptake in the thyroid bed on diagnosis whole-body scanning and a negative level of serum thyroglobulin.There were 327 patients enrolled between January 2013 and December 2014. More than 95% had papillary thyroid cancer. Data could be analyzed for 278 cases (MIn Chinese patients with differentiated thyroid carcinoma, the low dose of 1850 MBq radioiodine activity is as effective as a high dose of 3700 MBq for thyroid remnant ablation.

Immunotherapy has remarkable success outcomes against hematological malignancies with high rates of complete remission. To date, many studies have been conducted to increase its effectiveness in other types of cancer. However, it still yields unsatisfying results in solid tumor therapy. This limitation is partly attributed to the lack of understanding of how immunotherapy works in cancer from other perspectives. The traditional studies focus on the biological and chemical perspectives to determine which molecular substrates are involved in the immune system that can eradicate cancer cells. In the last decades, accumulating evidence has shown that physical properties also play important roles in the immune system to combat cancer, which is studied in mechanoimmunology. Mechanoimmunology analysis requires special tools; and herein, atomic force microscopy (AFM) appears as a versatile tool to determine and quantify the mechanical properties of a sample in nanometer precisions. Owing to its multifunctional capabilities, AFM can be used to explore immune system function from the physical perspective. This review paper explains the mechanoimmunology of how immune systems work through AFM, which includes mechanosignaling, mechanosensing, and mechanotransduction, with the aim to deepen the understanding of the mechanistic role of immunotherapy for further development in cancer treatment.

Local abnormal angiogenesis and cardiovascular system reorganization have been observed in embryos exposed to a simulated microgravity (SM) environment. In this study, changes in key molecular signals and pathways in cardiovascular development have been investigated under microgravity conditions. In particular, the caudal vein plexus (CVP) network, formed by sprouting angiogenesis has been chosen. Zebrafish embryos were exposed to SM using a ground-based microgravity bioreactor for 24 and 36 h. The SM was observed to have no effect on the zebrafish length, tail width and incubation time whereas it was observed to significantly reduce the heart rate frequency and to promote abnormal development of the CVP network in the embryos. Nitric oxide (NO) content demonstrated that the total proteins in zebrafish embryos were significantly higher in SM than in the control group grown under normal conditions. It was then preliminarily determined how NO signals were involved in SM regulated zebrafish CVP network formation. nos2b MO was injected and CVP network evolution was observed in 36 h post fertilization (hpf) under SM condition. The results showed that the CVP network formation was considerably decreased in the nos2b MO treated group. However, this inhibition of the CVP network development was not observed in control MO group, indicating that nos2b is involved in the SM-regulated vascular development process in zebrafish. Moreover, specific phosphoinositide 3-kinase (PI3K) inhibitors such as LY294002 were also tested on zebrafish embryos under SM condition. This treatment significantly inhibited the formation of zebrafish CVP network. Furthermore, overexpression of nos2b partly rescued the LY294002-caused CVP network failure. Therefore, it can be concluded that SM affects zebrafish CVP network remodeling by enhancing angiogenesis. Additionally, the PI3K-nos2b signaling pathway is involved in this process.

Rupture of atherosclerotic plaques causing thrombosis is the main cause of acute coronary syndrome and ischemic strokes. Inhibition of thrombosis is one of the important tasks developing biomedical materials such as intravascular stents and vascular grafts. Shear stress (SS) influences the formation and development of atherosclerosis. The current review focuses on the vulnerable plaques observed in the high shear stress (HSS) regions, which localizes at the proximal region of the plaque intruding into the lumen. The vascular outward remodelling occurs in the HSS region for vascular compensation and that angiogenesis is a critical factor for HSS which induces atherosclerotic vulnerable plaque formation. These results greatly challenge the established belief that low shear stress is important for expansive remodelling, which provides a new perspective for preventing the transition of stable plaques to high-risk atherosclerotic lesions.

Background The compromise of blood brain barrier (BBB) integrity is often associated with human hemorrhage stroke and neurodegeneration diseases, including retina diseases, such as age-related macular degeneration and diabetic retinopathy. Brain pericytes play pivotal roles in regulation and maintenance of BBB integrity. However, the mechanisms underlying brain pericyte development to establish BBB integrity remain unclear. Methods Zebrafish transgenic lines Tg(flk1:GFP; gata1:dsRed), Tg(flk1:GFP), Tg(fli1:GFP) and Tg(BRE:GFP) were used in this work. The functional studies of bmp3 were performed by mopholino oligonucleotide (MO) injection, dye-based permeability assay, RT-PCR, in vivo imaging, immunofluorescence staining and statics analysis. Results Here we report that bmp3 regulates BBB integrity in zebrafish brain by promoting pericyte development. Knockdown of bmp3 with injection of bmp3-MO causes intracerebral hemorrhage in zebrafish embryos. Meanwhile, disruption of bmp3 function by bmp3-MO injection impairs cerebral pericyte coverage in zebrafish embryos. Mechanistically, knockdown of bmp3 disrupts the pattern and activities of BMP signaling in zebrafish brain, thus probably disrupting the balance of TGFβ/BMP signaling in zebrafish embryos. Conclusion In summary, our data shows that bmp3 regulates BBB integrity potentially by promoting pericyte development.

Differentiated thyroid carcinoma (DTC) usually has a high iodine uptake. However, dedifferentiation of DTC with decreased or no radioiodine ((131)I) uptake is observed in clinical practice, with poor prognosis. The aim of this study was to investigate the effects of (131)I radiation on radioiodine uptake (RAIU) and the expression of thyroid-specific molecules.FTC-133 cells were treated with (131)I, the dosage dictated by methylthiazol tetrazolium test results and preliminary experiments. The experimental cell group was incubated with (131)I for 48 h and then cultured for 3 months in (131)I-free medium. The control group was set without (131)I. Primary cells were defined as the blank group. Following treatment, RAIU was measured with a gamma counter as the counts/cell number. Na(+)/I(-) symporter (NIS), thyroid-stimulating hormone receptor (TSHR), thyroid peroxidase (TPO) and thyroglobulin (Tg) levels were detected by Western blotting and radioimmunoassay, and their mRNAs were detected by real-time polymerase chain reaction.RAIU of FTC-133 cells decreased gradually after coincubation with (131)I and did not recover even if (131)I was removed. The relative RAIU of the control and experimental groups was 0.567 and 0.182, respectively, a statistically significant difference (P.01). Expression of NIS, TSHR, TPO and Tg decreased in the experimental group to a statistically significant degree compared to that of controls (P.05).Changes in the mRNA levels were in accordance with the expression of thyroid-specific proteins. Thus, FTC-133 cells undergo dedifferentiation during long-term culture in vitro, and (131)I may promote this progress.

Thyroid carcinoma is the most common malignant endocrine tumor, which comprises 1% in all human tumors. As for differentiated thyroid carcinoma (DTC), lymph nodes are the most common metastatic site for which the major treatment is (131)I therapy. This retrospective study aimed to investigate the therapeutic effect and analyze the influence factors on (131)I treatment of DTC with lymph node metastases.Collecting clinical data of 66 DTC patients with lymph node metastases at the Department of Nuclear Medicine, Xin Hua Hospital from January 1996 to January 2006. Investigating the therapeutic effect firstly and then dividing 66 patients into an eliminated group and an uneliminated group according to the evaluation criteria of the therapeutic effect. Finally, observing the differences between the two groups. The significant differences in the following 10 influence factors were determined: gender, age, pathological type, the periods from the thyroidectomy to the first (131)I therapy, when the metastases were found, the history of resection of the lymph node metastases, the uptake of (18)F-FDG in the lymph node metastases, remnant thyroid, multiple metastases, and the cumulative dose of (131)I. This retrospective study was analyzed by Student t test, chi(2) test, and Fisher's exact test.Of all 66 patients with lymph node metastatic DTC treated by (131)I therapy, 31 patients (46.97%) had complete elimination. Twenty-seven patients were improved or controlled, and the overall effective rate reached 87.88%. The elimination rate of lymph node metastases in patients with resection was significantly higher than in those without resection (chi(2)=5.561, P=.0180.05). The elimination rate of lymph node metastases in patients with (18)F-FDG uptake was significantly higher than in those without (18)F-FDG uptake (chi(2)=4.014, P=.045.05). There was no significant difference in the elimination rate among the patients with various values in the other eight factors.(131)I Therapy is an effective treatment of lymph node metastatic DTC. The history of resection of the lymph node metastases and the uptake of (18)F-FDG in the lymph node metastases were the influence factors on the therapeutic effect, whereas the other eight factors were probably not.

The aim of this study was to evaluate the efficacy of radioiodine remnant ablation (RRA) for differentiated thyroid carcinoma (DTC) patients with an incomplete thyroidectomy.The medical histories of postsurgical DTC patients who accepted RRA between 2010 and 2012 were retrospectively reviewed. Among them, 113 patients who had undergone a total or near-total thyroidectomy comprised the complete thyroidectomy group (CT group) and the remaining 40 patients who had undergone a lobectomy or sub-total thyroidectomy comprised the incomplete thyroidectomy group (ICT group). The difference in the patients' age, gender, histology, serum TSH level and 24hr radioactive iodine uptake (RIU) between the two groups was analyzed by χ2 Test or ANOVA. The efficacy of RRA in ICT group was evaluated by comparing its rate of complete ablation after the first RRA and its cumulative rate of complete ablation after the second RRA to the rate of complete ablation after the first RRA in CT group respectively by χ2 Test.Of all the clinical characteristics, only serum TSH level and 24hr RIU have significant difference between two groups (P0.01 for both). The rate of complete ablation after the first RRA was 67.26% in CT group. The rate of complete ablation after the first RRA and the cumulative rate of complete ablation after the second RRA was 27.50% and 67.50% respectively in ICT group. The ablative rate of the first RRA between the two groups was compared by χ2 Test and the difference was significant (P0.01). The ablative rate of the first RRA in CT group was compared with the cumulative rate of the second RRA in ICT group and the difference was not significant (P=0.978).Although the efficacy of RRA in DTC patients with an incomplete thyroidectomy is not as good as that of patients with a complete thyroidectomy after the first RRA, a higher ablative rate can still be achieved after the second or third RRA.

Heparin affinity chromatography of synthetic peptide fragments mimicking tissue factor pathway inhibitor (TFPI) indicated that the minimal heparin binding sequence consists of 12 amino acid residues located at the C-terminal tail. Within this minimal sequence, Arg-257 and Arg-259 appeared to contribute most significantly to interaction with heparin. Affinity chromatography of TFPI using immobilized heparin derivatives regiospecifically desulfated at O-6 of the glucosamine residue, N-2 of the glucosamine residue, and/or O-2 of the iduronic acid residue indicated that all the sulfate groups in heparin appeared to be required for TFPI-heparin interaction. Among them, however, the 6- O -sulfate groups appeared to make the largest contribution to the interaction, while the 2- O -sulfate groups contributed the least . In vitro experiments on the inhibition of factor Xa by TFPI enhanced with native and chemically modified heparins afforded similar results.

Chitosan is a natural biopolymer and is made up of D-glucosamine subunits linked by beta-(1,4) glycosidic bond. In recent years, the application of chitosan has attracted more and more attention because of its good biological function in cell biology. The properties of chitosan-based biomaterial are attributed to the physical properties and chemical composition of chitosan. The author of this paper summarized recent related studies and progresses of the influence of physical properties of chitosan on cell activity and cell mechanics property at home and abroad. The findings show that most studies mainly focused on the influence of chitosan and cell activity, while few were on cell mechanics property. The related studies of the influence of chitosan on cell will contribute to the explanation for the mechanism of the interaction between chitosan and cell, and provide the theoretical support for the further study.

Selectin/ligand interaction plays an important role in such biological processes as inflammatory reaction, tumor metastasis, etc. External forces affect dissociation of receptor-ligand bonds. A novel approach, upon optical trap technique, was developed in this study to investigate the dissociation of P-selectin/PSGL-1 (P-Selectin Glycoprotein Ligand 1) bindings. Stiffness of optical trap was calibrated with laser power using a viscous drag method. While P-selectin and PSGL-1 molecules were functionally coated on surfaces of glass beads, respectively, the dissociation of interacting molecule bond was studied by measuring the rupture force distribution. It was found that most probable rupture force increased with loading rate at25 pN/s. These results complemented and validated the current theory at low loading rates.

OBJECTIVE: To study the mechanism of rabbit lung injury caused by explosive decompression. METHODS: A total of 42 rabbits and 10 rats were served as the experimental animals. A slow recompression-decompression test and an explosive decompression test were applied to the animals, respectively. And the effects of the given tests on the animals were discussed. RESULTS: The slow recompression-decompression did not cause an obvious lung injury, but the explosive decompression did cause lung injuries in different degrees. The greater the decompression range was, the shorter the decompression duration was, and the heavier the lung injuries were. CONCLUSIONS: Explosive decompression can cause a similar lung injury as shock wave does. The primary mechanical causes of the lung injury might be a tensile strain or stress in the alveolar wall and the pulmonary surface's impacts on the inside wall of the chest.