Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 6.043
Filtrar
1.
Ultrason Sonochem ; 60: 104760, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31493716

RESUMO

Several typical high-velocity oxy-fuel (HVOF)-sprayed coatings, including WC-10Co4Cr coatings, Co-based coatings, WC-10Co4Cr/Co-based composite coatings, and Fe-based amorphous/nanocrystalline coatings were fabricated, and their cavitation behavior was evaluated in deionized water. Further, in-situ SEM surface observations were used to understand the microstructure of tested coatings. The results show that cavitation erosion initially occurred at pre-existing defects in the coatings. Meanwhile, it was found that cavitation erosion damage of the WC-10Co4Cr/Co-based composite coating, which contained a hard reinforcing phase (WC-10Co4Cr phase) and a soft matrix phase (Co-based phase), preferentially occurred at or around pores and microcracks in the reinforcement, rather than in the defect free matrix. This suggested that defects were a critical contributing factor to cavitation damage of the composite coatings. Furthermore, a mechanism was suggested to explicate the cavitation behavior of composite coatings. The approach of using in-situ SEM surface observations proved to be useful for the analysis of the cavitation mechanism of engineering materials and protective coatings.

2.
J Nanosci Nanotechnol ; 20(2): 1013-1019, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383099

RESUMO

Nanomaterial-based flexible strain sensors have developed rapidly in recent years. Here, we propose a flexible strain sensor based on polydimethylsiloxane with carbon nanotubes (CNTs) and graphene quantum dots (GQDs). Different weight ratios of CNTs and GQDs were used as the sensitive units of the strain sensors. After analyzing the results of current-voltage curves and the strain effects of the sensors, we concluded that the introduction of GQDs played an important role in improving the sensitivity of the sensors. The gauge factor of the as-prepared strain sensors ranges from 0 to 841.42.

3.
Chemosphere ; 239: 124708, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31505442

RESUMO

The discharge of phenol, a harmful pollutant, in the environment poses a threat to human health. With the rapid urbanization and industrialization of the land, there is a pressing need to find new technologies and efficient adsorption materials to address phenol contamination. As a potential adsorbent candidate, sepiolite (SEP) has garnered much interest owing to its large specific surface area, and excellent adsorption performance and biocompatibility. Herein, nanocomposite CESEP/ZIF-8, consisting of zeolite imidazole framework (ZIF-8) and hydrochloric acid-modified SEP (CESEP), was prepared and examined toward the adsorption of phenol. Adsorption equilibrium was achieved within 150 min at initial phenol solution concentrations of 10 and 20 mg/L. However, complete removal was not achieved. Accordingly, biodegradation was introduced. Microorganism Pseudomonas putida was immobilized onto CESEP/ZIF-8, which afforded synergistic adsorption and biodegradation action. Phenol at solution concentrations of 10 and 20 mg/L was effectively removed within 13 and 24 h, respectively (as opposed to 21 and 36 h when phenol was removed in the presence of free Pseudomonas putida solely). The synergistic physical-biological treatment presented herein is expected to have great potential in the field of wastewater treatment.

4.
J Enzyme Inhib Med Chem ; 35(1): 85-95, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31707866

RESUMO

To develop novel anti-inflammatory agents, a series of 5-alkyl-4-oxo-4,5-dihydro-[1, 2, 4]triazolo[4,3-a]quinoxaline-1-carboxamide derivatives were designed, synthesised, and evaluated for anti-inflammatory effects using RAW264.7 cells. Structures of the synthesised compounds were determined using 1H NMR, 13 C NMR, and HRMS. All the compounds were screened for anti-inflammatory activity based on their inhibitory effects against LPS-induced NO release. Among them, 5-(3,4,5-trimethoxybenzyl)-4-oxo-4,5-dihydro-[1, 2, 4]triazolo[4,3-a]quinoxaline-1-carboxamide (6p) showed the highest anti-inflammatory activity and inhibited NO release more potently than the lead compound D1. Further studies revealed that compound 6p reduced the levels of NO, TNF-α, and IL-6, and that its anti-inflammatory activity involves the inhibition of COX-2 and iNOS and downregulation of the mitogen-activated protein kinases (MAPK) signal pathway. Notably, compound 6p displayed more prominent anti-inflammatory activity than D1 and the positive control ibuprofen in the in vivo acute inflammatory model. Overall, these findings indicate that compound 6p is a therapeutic candidate for the treatment of inflammation.

5.
J Nanosci Nanotechnol ; 20(4): 2072-2078, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492214

RESUMO

Fluorescent organic dots have been widely utilized for various biological imaging. To obtain organic dots with high quantum yield (QY), different molecules with aggregation-induced emission (AIE) property and polymers with amphiphilic are used. By encapsulating AIE molecule 9,10-divinyl anthracene (DSA) with poly(styrene-co-maleic anhydride) and poly(isobutylene-alt-maleic anhydride) (PSMA and PIMA), novel bright AIE organic dots were obtained. The prepared AIE organic dots (PSMA dots and PIMA dots) had uniform particle size distribution, spherical appearance and small particle size (about 23 nm). However, PSMA dots had higher QYs than PIMA dots, and reached about 28.9% when the mass ratio of PSMA:DSA was 1:1. After folic acid (FA) conjugating to the surface of the PSMA dots, FA-dots were obtained. FA-dots possessed uniform particle size, good optical properties, stability and biocompatibility. The FA-dots could mark the cells where folate receptors were over-expressing. In vitro cell experiment indicated that FA-dots could be endocytosed into Hela cells, and marked the cell with specific.

6.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1134-1135: 121854, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31785534

RESUMO

Rosmarinus officinalis L., rosemary, is traditionally used to treat headache and improve cardiovascular disease partly due to its vasorelaxant activity, while the vasorelaxant ingredients remain unclear. In this study, chemical spectrum-pharmacological effect relationship (spectrum-effect relationship) was utilized for efficiently discovering the main vasorelaxant ingredients of rosemary. Ten kinds of rosemary extracts were prepared by different extracting solvents and macroporous resin purification, and their chemical components were analyzed by UPLC. At the same time, the vasorelaxant activities of the 10 kinds of rosemary extracts were estimated on isolated rat thoracic aorta, and three chemometrics named partial least squares regression (PLSR), grey correlation analysis (GRA), and the least absolute shrinkage and selection operator (LASSO) were applied to construct spectrum-effect relationship between the UPLC fingerprints and vasorelaxant activity of rosemary extracts. As a result, most rosemary extracts showed dose-dependent increase in vasorelaxant activity and five kinds of ingredients, including carnosol, carnosic acid, epirosmanol methyl ether, carnosol isomer, and augustic acid were screened as vasorelaxant ingredients. Further, the vasorelaxant activities of carnosic acid and carnosol were verified. Moreover, the increase of nitric oxide (NO) and the decrease of angiotensin-II (Ang-II) were thought to contribute to the vasorelaxant activity of rosemary.

7.
Stem Cells Dev ; 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31797736

RESUMO

In mammals, spermatogenesis is closely related to intercellular interactions of germ cells and surrounding Sertoli cells, i.e. blood-testis barrier (BTB) and gap junction, which are subjected to hormone signals in testicular seminiferous tubules. Androgen signal plays pivotal role in regulating spermatogenesis, but the underlying mechanism is largely unknown. Our recent study demonstrated a novel regulatory pattern of androgen in regulation of spermatogonia differentiation, which is androgen indirectly regulates the expression of ITGB1 on Sertoli Cells via intermediate molecule Wilms tumor-1 (Wt-1) during spermatogenesis. In this study, we identified that Connexin 43 (Cx43), the key component for gap junction distributed between spermatogonia and Sertoli cells, was also regulated by androgen signal. Chromatin immunoprecipitation quantitative PCR (ChIP-qPCR) demonstrated that WT1 occupied Cx43 promoter in Sertoli cells, suggesting WT1 as an intermediate molecule in regulation of Cx43. Finally, we revealed a regulatory pattern of Cx43 by androgen in Sertoli cells, and the Sertoli cells in germ cell depleted microenvironment were sensitive to androgen signal, which enhances the understanding of the mechanism of spermatogenesis.

8.
Endocrine ; 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31786774

RESUMO

PURPOSE: Serum complement C3 has been shown to contribute to the incidence of type 2 diabetes (T2D), but how serum complement C3 affects islet ß-cell function throughout the course of T2D is unclear. This study explored whether serum complement C3 is independently associated with changes in islet ß-cell function over time in patients with T2D. METHODS: Serum complement C3 was measured, and endogenous ß-cell function was evaluated by area under the C-peptide curve (AUCcp) during an oral glucose tolerance test (OGTT) in 411 patients with T2D at baseline from 2011 to 2015. Next, 347 of those patients with available data were pooled for a final follow-up analysis from 2014 to 2018. Changes in islet ß-cell function at follow-up were evaluated by AUCcp percentage changes (ΔAUCcp%). In addition, other possible clinical risks for diabetes were also examined. RESULTS: The 347 patients included in the analysis had a diabetes duration of 4.84 ± 3.63 years at baseline. Baseline serum complement C3 (baseline C3) levels were positively correlated with baseline natural logarithm of AUCcp (lnAUCcp) (n = 347, r = 0.288, p < 0.001), and baseline C3 was independently associated with baseline lnAUCcp (ß = 0.17, t = 3.52, p < 0.001) after adjustment for baseline glycemic status and other clinical confounders by multivariate liner regression analysis. Compared with the baseline values, complement C3 changes (ΔC3) and ΔAUCcp% was -0.15 ± 0.28 mg/ml and -17.2 ± 18.4%, respectively, at a follow-up visit 4.57 ± 0.78 years later. Moreover, ΔC3 was positively correlated with ΔAUCcp% (n = 347, r = 0.302, p < 0.001). Furthermore, each 0.1 mg/ml increase in ΔC3 was associated with a higher ΔAUCcp% (1.41% [95% CI, 0.82-2.00%]) after adjusting for changes in glycemic status and other clinical confounders at follow-up. CONCLUSIONS: In addition to serum complement C3 being independently associated with islet ß-cell function at baseline, its changes were also independently associated with changes in islet ß-cell function over time in patients with T2D.

9.
Mol Med Rep ; 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31789409

RESUMO

Toll­like receptors (TLRs) are the most widely studied pattern recognition receptors. Mounting evidence suggests an important association between TLRs and the occurrence and development of breast cancer. Thus, targeting these receptors may be a potential strategy for breast cancer treatment. The current study analyzed the data of 1,215 patients with breast cancer obtained from The Cancer Genome Atlas (TCGA) database. It was observed that, in addition to TLR6, TLR7 and TLR8, the expression of the remaining TLRs in breast cancer tissues was lower than that in normal tissues. In addition, TLR3 and TLR9 displayed significantly different expression levels in ER­/PR­negative breast cancer compared with the control tissues, while TLR5 expression was significantly reduced in HER2­enriched breast cancer. Furthermore, TLR10 exhibited lower expression levels in advanced stages of the disease as compared with that observed in earlier stages. Survival analysis revealed that the expression of TLR4 and TLR7 had a significant impact on survival, and higher expression levels suggested worse prognosis. Finally, the expression levels of TLR1, TLR2, TLR4, TLR5, TLR6 and TLR10 were correlated with those of the inflammatory cytokines interleukin­1ß and tumor necrosis factor­α, while the expression levels of TLR3, TLR7, TLR8 and TLR9 were correlated with those of interferon­ß and C­X­C motif chemokine ligand 10. Taken together, the current study results suggest that TLR expression may serve as a biomarker of cancer pathogenesis and progression, and may provide new insights for the treatment of breast cancer through the regulation and targeting of TLRs.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31784083

RESUMO

Interleukin-17 (IL-17) and interferon-γ (IFN-γ), two inflammatory cytokines, are present in cancerous liver tissues. IL-17 was recently identified as an oncogenic factor in hepatocellular carcinoma (HCC), but its underlying mechanisms are largely obscure. Here, we aimed to investigate the interaction between IL-17 and IFN-γ and its influence on HCC cell apoptosis and growth in vitro and in vivo. We found that the expression of IL-17, but not IFN-γ, was obviously increased in HCC tissues. Higher IL-17 expression in tumor tissues correlated with shorter survival times. IFN-γ apparently increased apoptosis of HCC cells. IL-17 alone had no effect on apoptosis of HCC cells but reversed apoptosis induced by IFN-γ. IFN-γ mildly promoted the expression of protein inhibitor of activated signal transducer and activators of transcription 1 (PIAS1) and the activation of NF-κB, and these effects were greatly enhanced when combined with IL-17. PIAS1 silencing not only further amplified apoptosis induced by IFN-γ alone but also abolished the inhibitory effects of IL-17 on IFN-γ-induced apoptosis in HCC cells. An NF-κB inhibitor obviously decreased the upregulated expression of PIAS1 induced by IFN-γ plus IL-17 and IFN-γ alone. IFN-γ treatment retarded the tumor growth of HCC cells in an in vivo xenograft tumor model, which could be largely inhibited by combined treatment with IL-17. In conclusion, IL-17 obviously inhibits the antitumor effects of IFN-γ in hepatoma cells and, in turn, accelerates HCC development through upregulating the expression of the negative feedback regulator PIAS1 of the JAK/STAT1 pathway via enhancing activation of NF-κB.

11.
Chem Commun (Camb) ; 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31802084

RESUMO

Silicon (Si) is a promising candidate as an anode material for lithium-ion batteries. However, its application is hindered by poor cycling stability and rate-capability due to structural degradation, resulting from large volume changes during cyclic charging and discharging. In this paper, we report that uniform-sized Si@void@C nanoparticles can be prepared by magnesiothermic reduction of SiO2@void@C. Si nanoparticles are in hollow carbon shells with a large void space between the carbon shell and particles. Thus, each Si particle can expand freely within the well-designed void space without destroying the outer carbon shell, and benefit the solid-electrolyte interphase film stabilization on the carbon shell. The new material shows a high capacity of 1598 mA h g-1 at a current density of 1 A g-1, a long cycle life of 1500 cycles with 85% capacity retention, and a high Coulombic efficiency of 99.6% as well, and might be a promising Si-based anode material for Li-ion battery applications.

12.
Opt Express ; 27(22): 31864-31873, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684410

RESUMO

Entangled coherent states for multiple bosonic modes, also referred to as multimode cat states, not only are of fundamental interest but also have practical applications. The nonclassical correlation among these modes is well characterized by the violation of the Mermin-Klyshko inequality. We here study Mermin-Klyshko inequality violations for such multi-mode entangled states with rotated quantum-number parity operators. It is shown that the Mermin-Klyshko signal obtained with these operators can approach the maximal value even when the average quantum number in each mode is only 1, and the inequality violation exponentially increases with the number of entangled modes. This is in distinct contrast with the framework based on displaced parity operators, with which a nearly maximal Mermin-Klyshko inequality violation requires the size of the cat state to be increased by about 15 times.

13.
J Reprod Dev ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31735743

RESUMO

One major side effect of chemotherapy that young women with cancer suffer from is ovarian damage. Therefore, it is necessary to study the pathogenesis of chemotherapeutic drugs in order to develop pharmaceutical agents to preserve fertility. Epirubicin is one of the commonly used chemotherapy drugs for breast cancer patients. This research explored the side effects of epirubicin in mice. We found that epirubicin significantly reduced the body weight, the weight of the ovaries and uteri, and the pups' number, while melatonin, which is extremely resistant to oxidation, significantly reduced these damages. Moreover, co-treatment with melatonin prevented epirubicin-induced decrease in E2 and progesterone, and the loss of follicles. Mechanism study showed that melatonin significantly reduced the levels of proapoptotic genes p53, Caspase3, and Caspase9 while it upregulated antiapoptotic factors Bcl-2 and Bcl2l1, and antioxidant genes superoxide dismutase 1 and catalase compared with the epirubicin group. In addition, melatonin markedly reduced reactive oxygen species (ROS) and the transcription of Caspase12 and Chop, which is vital in endoplasmic reticulum stress (ERS)-mediated apoptosis. These results indicate melatonin protects against epirubicin-induced ovarian damage by reducing ROS-induced ERS. Therefore, melatonin has a therapeutic potential for the protection of ovarian function and preservation of fertility during chemotherapy.

14.
Phytother Res ; 2019 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-31736181

RESUMO

The intestinal epithelium provides the first line of defense against pathogens and toxic compounds. The ingestion of toxic compounds causes an enhanced epithelial cell death and an excessive proliferation of intestinal stem cells, eventually resulting in the disruption of gut homeostasis. In this study, Drosophila gut inflammation model induced by toxic compounds was exploited to analyze the ameliorative effect of Acanthopanax senticosus polysaccharide on the disruption of gut homeostasis. As a result, it was found that A. senticosus polysaccharide can significantly increase the survival rate of Drosophila adults as well as reduce the excessive proliferation and differentiation of intestinal stem cells through epidermal growth factor receptor, jun-N-terminal kinase, and Notch signaling pathways under the exposure to toxic compounds dextran sodium sulfate. Moreover, the polysaccharide effectively decreased the epithelial cell death and the accumulation of reactive oxygen species and antimicrobial peptides induced by sodium dodecyl sulfate. In addition, it was found that A. senticosus polysaccharide can extend the lifespan of only female flies but not male flies. In conclusion, A. senticosus polysaccharide has an obvious protective effect on the gut homeostasis of Drosophila melanogaster.

15.
Chin Med J (Engl) ; 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31764191

RESUMO

BACKGROUND: Post-operative pain is unpleasant for patients and may worsen surgical recovery. Peri-operative multimodal analgesia has been used for many years; however, its efficacy still needs improvement. In the present study, a thorough peri-operative pain counseling and stratified management program based on risk assessment was implemented, with the goal of improving post-operative analgesia and patient satisfaction. METHODS: This prospective, controlled, pilot study included 361 patients who underwent elective surgery. Of these 361 patients, 187 received peri-operative pain risk assessment and stratified analgesia and counseling (stratified analgesia group), while 174 received conventional multimodal analgesia (conventional group). The two groups were compared regarding the post-operative pain intensity, rescue analgesia administration, post-operative quality of recovery as assessed via the quality of recovery 40 questionnaire, total dosage of peri-operative opioids, analgesic satisfaction, and analgesic costs. RESULTS: Compared with the conventional group, the stratified analgesia group reported decreased pain intensity during motion at 24 h post-operatively and required lower dosages of rescue analgesia (P = 0.03). The total quality of recovery 40 questionnaire score and the scores for physical wellbeing and pain were significantly better in the stratified analgesia group than the conventional group (P = 0.04); the stratified analgesia group also reported better scores for analgesic satisfaction (P = 0.03) and received lower dosages of opioids (P = 0.03). Analgesic costs were lower in the stratified analgesia group than the conventional group; the cost-effective ratio was 109 in the conventional group and 62 in the stratified analgesia group. CONCLUSIONS: The analgesic efficacy was improved by the implementation of stratified analgesia based on surgical pain risk assessment and counseling. This stratified analgesia protocol increased the patients' analgesic satisfaction and improved the quality of recovery without increasing healthcare costs. The present findings may help improve the efficacy of peri-operative multimodal analgesia in clinical practice. CLINICAL TRIAL REGISTRY: NCT02728973; https://clinicaltrials.gov/ct2/show/NCT02728973?term=NCT02728973&draw=2&rank=1.

16.
J Craniofac Surg ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31764567

RESUMO

OBJECTIVE: To summarize the prognosis of pediatric patients with mucoepidermoid carcinoma (MEC) of the parotid gland. METHODS: Pediatric patients with MEC of parotid gland who were surgically treated at the Capital Medical University School of Stomatology from 2000 to 2014 were retrospectively analyzed. Clinical characteristics, pathology reports, and operation records were reviewed and analyzed. RESULTS: In total, 33 patients with an average age of 13.2 years were enrolled. The 5-year overall survival and disease-free survival were 95.8% and 84.4%, respectively. The disease-free survival and overall survival rates were lower in the under-10 age group (75.0 versus 87.7% and 83.3% versus 100%), though no statistically significant difference was found (P = 0.279 and P = 0.075). The patients who underwent complete resection all had a good prognosis without any recurrence or death regardless of whether the cut margin was 1.0 cm, 0.5 cm, or only extracapsular. One patient experienced 3 recurrences within 18 months and eventually died of disease. CONCLUSION: Good outcomes were achieved in pediatric patients with MEC of the parotid gland. Radical resection ensured a good prognosis regardless of the extent of resection. Frequent recurrence in a short period was associated with a poor prognosis. TRIAL REGISTRATION: None.

17.
Medicine (Baltimore) ; 98(44): e17797, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689857

RESUMO

RATIONALE: Acute necrotizing encephalopathy (ANE) is a rapidly progressing disease associated with frequent neurologic sequelae and has poor prognosis. Currently, the diagnosis and treatment of ANE rely on neuroradiologic findings and offering supportive care. Here, we report the successful treatment of a teenager diagnosed with ANE using combination of high-dose methylprednisolone and oseltamivir. PATIENT CONCERNS: The patient, a 15-year-old female, presented with impaired consciousness and seizures secondary to acute upper respiratory tract infection. A series of brain magnetic resonance images (MRIs) were obtained toward establishing a possible diagnosis. DIAGNOSIS: Based on the history of presenting illness and subsequent brain MRI scans, the patient was diagnosed to be suffering from ANE. INTERVENTIONS: Following the diagnosis, the patient was placed on therapy comprising of high-dose methylprednisolone and oseltamivir. OUTCOMES: After treatment with methylprednisolone and oseltamivir for 15 days, the patient recovered nearly completely from ANE as confirmed by subsequent brain MRI scans. No complications or other emerging clinical symptoms were noted for the duration of follow-up that lasted 6 months. LESSONS: Contrary to common reports, ANE can occur beyond pediatric populations and its treatment should not be restricted to supportive care. Our case suggests that the use of high-dose corticosteroids and oseltamivir leads to promising prognosis.


Assuntos
Encéfalo/diagnóstico por imagem , Encefalite Viral/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Infecções Respiratórias/complicações , Convulsões/diagnóstico por imagem , Adolescente , Corticosteroides/uso terapêutico , Antivirais/uso terapêutico , Encéfalo/patologia , Encéfalo/virologia , China , Encefalite Viral/tratamento farmacológico , Encefalite Viral/virologia , Feminino , Humanos , Necrose/diagnóstico por imagem , Necrose/virologia , Oseltamivir/uso terapêutico , Prognóstico , Infecções Respiratórias/virologia , Convulsões/patologia , Convulsões/virologia
18.
Small ; : e1905731, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31668013

RESUMO

Memristors are emerging as a rising star of new computing and information storage techniques. However, the practical applications are severely challenged by their instability toward harsh conditions, including high moisture, high temperatures, fire, ionizing irradiation, and mechanical bending. In this work, for the first time, lead-free double perovskite Cs2 AgBiBr6 is utilized for environmentally robust memristors, enabling highly efficient information storage. The memory performance of the typical indium-tin-oxide/Cs2 AgBiBr6 /Au sandwich-like memristors is retained after 1000 switching cycles, 105 s of reading, and 104 times of mechanical bending, comparable to other halide perovskite memristors. Most importantly, the memristive behavior remains robust in harsh environments, including humidity up to 80%, temperatures as high as 453 K, an alcohol burner flame for 10 s, and 60 Co γ-ray irradiation for a dosage of 5 × 105 rad (SI), which is not achieved by any other memristors and commercial flash memory techniques. The realization of an environmentally robust memristor from Cs2 AgBiBr6 with a high memory performance will inspire further development of robust electronics using lead-free double perovskites.

19.
Magn Reson Med ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31765494

RESUMO

PURPOSE: Cell size is a fundamental characteristic of all tissues, and changes in cell size in cancer reflect tumor status and response to treatments, such as apoptosis and cell-cycle arrest. Unfortunately, cell size can currently be obtained only by pathological evaluation of tumor tissue samples obtained invasively. Previous imaging approaches are limited to preclinical MRI scanners or require relatively long acquisition times that are impractical for clinical imaging. There is a need to develop cell-size imaging for clinical applications. METHODS: We propose a clinically feasible IMPULSED (imaging microstructural parameters using limited spectrally edited diffusion) approach that can characterize mean cell sizes in solid tumors. We report the use of a combination of pulse sequences, using different gradient waveforms implemented on clinical MRI scanners and analytical equations based on these waveforms to analyze diffusion-weighted MRI signals and derive specific microstructural parameters such as cell size. We also describe comprehensive validations of this approach using computer simulations, cell experiments in vitro, and animal experiments in vivo and demonstrate applications in preoperative breast cancer patients. RESULTS: With fast acquisitions (~7 minutes), IMPULSED can provide high-resolution (1.3 mm in-plane) mapping of mean cell size of human tumors in vivo on clinical 3T MRI scanners. All validations suggest that IMPULSED provides accurate and reliable measurements of mean cell size. CONCLUSION: The proposed IMPULSED method can assess cell-size variations in tumors of breast cancer patients, which may have the potential to assess early response to neoadjuvant therapy.

20.
Zhen Ci Yan Jiu ; 44(11): 832-4, 2019 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-31777234

RESUMO

OBJECTIVE: To observe the efficacy of "Buqi Yixue "needling on clinical symptoms, neurological function and nerve conduction velocity in patients with diabetic peripheral neuropathy. METHODS: Eighty-six patients with diabetic peripheral neuropathy numbness and pain were equally randomized into control group and treatment group. The patients of the control group received basic treatment and oral administration of Cilostazol (50 mg/time, 2 times/d) and Epalrestat (50 mg/time, 3 times/d). The patients of the treatment group received acupuncture stimulation of Danzhong (CV17), Qihai (CV6), Pishu (BL20), Quchi (LI11), etc., for 30 min, once every day, on the basic treatment. The treatment was conducted for 8 successive weeks. The scores of Traditional Chinese Medicine (TCM) symptoms, Toronto clinical scoring system (TCSS) and nerve conduction velocity (NCV) were detected before and after the treatment. RESULTS: After the treatment, the scores of TCM symptoms and TCSS were considerably decreased (P<0.05), and the NCV was significantly increased (P<0.05) in both groups compared with those of their own pre-treatment. The the-rapeutic effect of the treatment group was significantly superior to that of the control group in lowering the scores of TCM symptoms and TCSS, and in up-regulating the NCV (P<0.01). CONCLUSION: "Buqi Yixue" needling is effective in improving clinical symptoms and increasing NCV in patients with diabetic peripheral neuropathy.


Assuntos
Terapia por Acupuntura , Neuropatias Diabéticas , Artérias , Diabetes Mellitus , Neuropatias Diabéticas/terapia , Humanos , Medicina Tradicional Chinesa , Condução Nervosa
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA