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Innovation design of medical equipment based on TRIZ

Changqing Gao, Leiming Guo, Fenglan Gao, Bo Yang, Edward J. Ciaccio
2015 Technology and Health Care  
BACKGROUND: Medical equipment is closely related to personal health and safety, and this can be of concern to the equipment user. Furthermore, there is much competition among medical equipment manufacturers. Innovative design is the key to success for those enterprises. OBJECTIVE: The design of medical equipment usually covers vastly different domains of knowledge. The application of modern design methodology in medical equipment and technology invention is an urgent requirement. METHODS: TRIZ
more » ... Russian abbreviation of what can be translated as 'theory of inventive problem solving') was born in Russia, which contain some problem-solving methods developed by patent analysis around the world, including Conflict Matrix, Substance Field Analysis, Standard Solution, Effects, etc. TRIZ is an inventive methodology for problems solving. RESULTS: As an Engineering example, infusion system is analyzed and re-designed by TRIZ. The innovative idea is generated to liberate the caretaker from the infusion bag watching out. The research in this paper shows the process of the application of TRIZ in medical device inventions. CONCLUSION: It is proved that TRIZ is an inventive methodology for problems solving and can be used widely in medical device development.
doi:10.3233/thc-150962 pmid:26410492 fatcat:nm75wypr4bgifa3whv24h66eoy

Clinical outcomes of rectal carcinoids: A single-institution experience

Yue Jiang, Yufei Lu, Xiaoli Zheng, Leiming Guo, Xijuan Chen
2014 Journal of Clinical Oncology  
To report clinical outcomes of rectal carcinoids through investigating patients with rectal carcinoid. Between December 2011 and January 2003, 16 consecutive patients with biopsy-proven rectal carcinoid were enrolled at our institution, including ten males and six females, with a medial age of 49 years old (range 29 to 78 years). The median tumor size was 12.3mm, five lesions diameter were ≥ 20mm, eight lesions diameter were ≤ 10mm, three lesions diameter were 10mm-20mm. All rectal lesions were
more » ... located within 10cm from the anal verge. 9 cases underwent transanal local excision; 3 cases had received anterior resection (Dixon); 2 cases underwent abdominaloperineal resection (APR); 2 cases underwent Endoscopic submucosal dissection (ESD).2 of patients received postoperative chemotherapy or radiation therapy. Calculation of the 5-year overall survival (OS), recurrence-free survival (RFS) and cancer specific survival (CSS) were performed by Kaplan-Meier methodology. All patients were followed up for a median of 45.4 months (Range: 6 to 161 months), no patient was lost to follow-up. The 5-year OS, RFS and CSS were 85.2%, 93.8% and 90.9% respectively. Rectal carcinoids had a favorable prognosis, an adequate resection play key role in management of rectal carcinoid tumors, the extent of the surgical resection depend on its size, its anticipated stage and the specific patient needs.
doi:10.1200/jco.2014.32.15_suppl.e14652 fatcat:nklnn4lmsfhjzj4evzijpwgjnu

Design of gradient nanopores in phenolics for ultrafast water permeation

Leiming Guo, Yazhi Yang, Fang Xu, Qianqian Lan, Mingjie Wei, Yong Wang
2019 Chemical Science  
Ultra-permeable and robust membranes are prepared by creating a gradient nanoporous structure in low-cost phenolics, enabled by the spontaneous assembly of gradually enlarged phenolic nanoparticles.
doi:10.1039/c8sc03012j pmid:30842866 pmcid:PMC6375355 fatcat:aaawxvyds5aa7mnpeq3zeovwxq

A Cell-Level Systems PK-PD Model to Characterize In Vivo Efficacy of ADCs

Aman Singh, Leiming Guo, Ashwni Verma, Gloria Wong, Dhaval Shah
2019 Pharmaceutics  
Here, we have presented the development of a systems pharmacokinetics-pharmacodynamics (PK-PD) model for antibody-drug conjugates (ADCs), which uses intracellular target occupancy to drive in-vivo efficacy. The model is built based on PK and efficacy data generated using Trastuzumab-Valine-Citrulline-Monomethyl Auristatin E (T-vc-MMAE) ADC in N87 (high-HER2) and GFP-MCF7 (low-HER2) tumor bearing mice. It was observed that plasma PK of all ADC analytes was similar between the two tumor models;
more » ... wever, total trastuzumab, unconjugated MMAE, and total MMAE exposures were >10-fold, ~1.6-fold, and ~1.8-fold higher in N87 tumors. In addition, a prolonged retention of MMAE was observed within the tumors of both the mouse models, suggesting intracellular binding of MMAE to tubulin. A systems PK model, developed by integrating single-cell PK model with tumor distribution model, was able to capture all in vivo PK data reasonably well. Intracellular occupancy of tubulin predicted by the PK model was used to drive the efficacy of ADC using a novel PK-PD model. It was found that the same set of PD parameters was able to capture MMAE induced killing of GFP-MCF7 and N87 cells in vivo. These observations highlight the benefit of adopting a systems approach for ADC and provide a robust and predictive framework for successful clinical translation of ADCs.
doi:10.3390/pharmaceutics11020098 pmid:30823607 pmcid:PMC6409735 fatcat:7lmljbvdjjg35j5sdr63ofe3sq

Ultrasensitive Terahertz Biosensors Based on Fano Resonance of a Graphene/Waveguide Hybrid Structure

Banxian Ruan, Jun Guo, Leiming Wu, Jiaqi Zhu, Qi You, Xiaoyu Dai, Yuanjiang Xiang
2017 Sensors  
Guo et al. proposed a structure composed of few layer graphene (FLG) and PWG to realize Fano resonance in mid-infrared wavelengths [23] .  ...  Guo et al. proposed a structure composed of few layer graphene (FLG) and PWG to realize Fano resonance in mid-infrared wavelengths [23] .  ... 
doi:10.3390/s17081924 pmid:28825677 pmcid:PMC5580221 fatcat:dnmghmeetjfhxf3opa5jtl3b2q

Effect of Size on Solid Tumor Disposition of Protein Therapeutics

Zhe Li, Yingyi Li, Hsuan-Ping Chang, Hsueh-Yuan Chang, Leiming Guo, Dhaval K Shah
2019 Drug Metabolism And Disposition  
In this study, we evaluated the effect of size on tumor disposition of protein therapeutics, including the plasma and tumor pharmacokinetics (PK) of trastuzumab (∼150 kDa), FcRn-nonbinding trastuzumab (∼150 kDa), F(ab)2 fragment of trastuzumab (∼100 kDa), Fab fragment of trastuzumab (∼50 kDa), and trastuzumab scFv (∼27 kDa) in both antigen (i.e., HER2)-overexpressing (N87) and antigen-nonexpressing (MDA-MB-468) tumor-bearing mice. The observed data were used to develop the maximum tumor uptake
more » ... ersus molecular weight and tumor-to-plasma area under the curve (AUC) ratio versus molecular weight relationships. Comparison of the PK of different sizes of FcRn nonbinding molecules in target-expressing tumor showed that ∼100 kDa is an optimal size to achieve maximum tumor uptake and ∼50 kDa is an optimal size to achieve maximum tumor-to-plasma exposure ratio of protein therapeutics. The PK data were also used to validate a systems PK model for tumor disposition of different-sized protein therapeutics. The PK model was able to predict a priori the PK of all five molecules in both tumor types reasonably well (within 2- to 3-fold). In addition, the model captured the bell-shaped relationships observed between maximum tumor uptake and molecular weight and between tumor-to-plasma AUC ratio and molecular weight. Our results provide an unprecedented insight into the effect of size and target engagement on the tumor PK of protein therapeutics. Our results also provide further validation of the tumor disposition model, which can be used to support discovery, development, and preclinical-to-clinical translation of different sizes of protein therapeutics. SIGNIFICANCE STATEMENT: This article highlights the importance of molecular size and target engagement on the tumor disposition of protein therapeutics. Our results suggest that ∼100 kDa is an optimal size to achieve maximum tumor uptake and ∼50 kDa is an optimal size to achieve maximum tumor-to-plasma exposure ratio for non-FcRn-binding targeted protein therapeutics. We also demonstrate that a systems pharmacokinetics model developed to characterize tumor disposition of protein therapeutics can predict a priori the disposition of different-sized protein therapeutics in target-expressing and target-nonexpressing solid tumors.
doi:10.1124/dmd.119.087809 pmid:31387870 pmcid:PMC6756290 fatcat:wc5oc57a5rbxpovv2fd2xkkrtq

Porous block copolymer separation membranes for 21st century sanitation and hygiene

Leiming Guo, Yong Wang, Martin Steinhart
2021 Chemical Society Reviews  
Removing hazardous particulate and macromolecular contaminants as well as viruses with sizes from a few nm up to the 100 nm-range from water and air is crucial for ensuring sufficient sanitation and hygiene for a growing world population. To this end, high-performance separation membranes are needed that combine high permeance, high selectivity and sufficient mechanical stability under operating conditions. However, design features of separation membranes enhancing permeance reduce selectivity
more » ... nd vice versa. Membrane configurations combining high permeance and high selectivity suffer in turn from a lack of mechanical robustness. These problems may be tackled by using block copolymers (BCPs) as a material platform for the design of separation membranes. BCPs are macromolecules that consist of two or more chemically distinct block segments, which undergo microphase separation yielding a wealth of ordered nanoscopic domain structures. Various methods allow the transformation of these nanoscopic domain structures into customized nanopore systems with pore sizes in the sub-100 nm range and with narrow pore size distributions. This tutorial review summarizes design strategies for nanoporous state-of-the-art BCP separation membranes, their preparation, their device integration and their use for water purification.
doi:10.1039/d0cs00500b pmid:33890584 fatcat:dmwyd7tjsrcs5iri4zrwnaahfe

m6A in mRNA coding regions promotes translation via the RNA helicase-containing YTHDC2

Yuanhui Mao, Leiming Dong, Xiao-Min Liu, Jiayin Guo, Honghui Ma, Bin Shen, Shu-Bing Qian
2019 Nature Communications  
Dynamic mRNA modification in the form of N6-methyladenosine (m6A) adds considerable richness and sophistication to gene regulation. The m6A mark is asymmetrically distributed along mature mRNAs, with approximately 35% of m6A residues located within the coding region (CDS). It has been suggested that methylation in CDS slows down translation elongation. However, neither the decoding feature of endogenous mRNAs nor the physiological significance of CDS m6A has been clearly defined. Here, we found
more » ... that CDS m6A leads to ribosome pausing in a codon-specific manner. Unexpectedly, removing CDS m6A from these transcripts results in a further decrease of translation. A systemic analysis of RNA structural datasets revealed that CDS m6A positively regulates translation by resolving mRNA secondary structures. We further demonstrate that the elongation-promoting effect of CDS methylation requires the RNA helicase-containing m6A reader YTHDC2. Our findings established the physiological significance of CDS methylation and uncovered non-overlapping function of m6A reader proteins.
doi:10.1038/s41467-019-13317-9 pmid:31767846 pmcid:PMC6877647 fatcat:wmfheer3dfhiziiftcsn5d2use

Silicon Substrate Treated with Diluted NaOH Aqueous for Si/PEDOT: PSS Heterojunction Solar Cell with Performance Enhancement

Tao Chen, Hao Guo, Leiming Yu, Tao Sun, Yu Yang
2020 Energies  
Si/PEDOT: PSS solar cell is an important alternative for photovoltaic device due to its anticipated high theoretical efficiency and simple manufacturing process. In this study, processing silicon substrate with diluted NaOH aqueous solution was found to be an effective method for improving device performance, one that notably improves junction quality and light trapping ability. When immersed in diluted NaOH aqueous solution, the junction quality was improved according to the enlarged fill
more » ... r, reduced series resistance, and enhanced minor carrier lifetime. The diluted NaOH aqueous solution immersion etched the silicon surface and helped with the enhancement of light trapping ability, further improving the short-circuit current density. Although diluted NaOH aqueous solution immersion for bare silicon could improve the performance of devices, proper immersion time was needed. The influence of immersion time on device performances was investigated. The photovoltaic conversion efficiency easily increased from 10.01% to 12.05% when silicon substrate was immersed in diluted NaOH aqueous for 15 min. This study contributes to providing efficient and convenient methods for preparing high performance Si/PEDOT: PSS solar cells.
doi:10.3390/en13184659 fatcat:lqvnrynkjbdyjoz44ogqfhulaq

Magnetic critical behavior of the van der Waals Fe5GeTe2 crystal with near room temperature ferromagnetism [article]

Zhengxian Li, Wei Xia, Hao Su, Zhenhai Yu, Yunpeng Fu, Leiming Chen, Xia Wang, Na Yu, Zhiqiang Zou, Yanfeng Guo
2020 arXiv   pre-print
The van der Waals ferromagnet Fe5GeTe2 has a Curie temperature TC of about 270 K, which can be raised above room temperature by tuning the Fe deficiency content. To achieve insights into its ferromagnetic exchange, we have studied the critical behavior by measuring the magnetization in bulk Fe5GeTe2 crystal around the ferromagnetic to paramagnetic phase transition. The analysis of the magnetization by employing various techniques including the modified Arrott plot, Kouvel-Fisher plot and
more » ... l isotherm analysis achieved a set of reliable critical exponents with TC = 273.7 K, beta = 0.3457, gamma = 1.40617, and delta = 5.021, suggesting a three-dimensional magnetic exchange with the distance decaying as J(r) (r)^-4.916, which is close to that of a three-dimensional Heisenberg model with long-range magnetic coupling.
arXiv:2003.06825v1 fatcat:xnxdezxnq5evjhhc7tjog4r63q

The de Hass-van Alphen quantum oscillations in BaSn3 superconductor with multiple Dirac fermions [article]

Gaoning Zhang, Xianbiao Shi, Xiaolei Liu, Wei Xia, Hao Su, Leiming Chen, Xia Wang, Na Yu, Zhiqiang Zou, Weiwei Zhao, Yanfeng Guo
2020 arXiv   pre-print
By measuring the de Hass-van Alphen effect and calculating the electronic band structure, we have investigated the bulk Fermi surface of the BaSn3 superconductor with a transition temperature of 4.4 K. Striking de Haas-van Alphen (dHvA) quantum oscillations are observed when the magnetic field B is perpendicular to both (100) and (001) planes. Our analysis unveiled nontrivial Berry phase imposed in the quantum oscillations when B is perpendicular to (100), with two fundamental frequencies at
more » ... 5 T and 306.7 T, which likely arise from two corresponding hole pockets of the bands forming a type-II Dirac point. The results are supported by the ab initio calculations indicating a type-II Dirac point setting and tilting along the high symmetric K-H line of the Brillouin zone, about 0.13 eV above the Fermi level. Moreover, the calculations also revealed other two type-I Dirac points on the high symmetric Γ-A direction, but slightly far below the Fermi level. The results demonstrate BaSn3 as an excellent platform for the study of not only exotic properties of different types of Dirac fermions in a single material, but also the interplay between nontrivial topological states and superconductivity.
arXiv:2001.08359v1 fatcat:phorzuewybay5bag2cemsundzq

Topological insulator overlayer to enhance the sensitivity and detection limit of surface plasmon resonance sensor

Jiaqi Zhu, Yuxuan Ke, Jianfeng Dai, Qi You, Leiming Wu, Jianqing Li, Jun Guo, Yuanjiang Xiang, Xiaoyu Dai
2019 Nanophotonics  
Surface plasmon resonance (SPR) sensors have been applied in a wide range of applications for real-time and label-free detection. In this article, by covering the topological insulators nanosheets on the surface of the noble metal (Au), the sensitivity of the SPR sensor is greatly enhanced because of the strong interaction of light with Au–bismuth selenide (Bi2Se3) heterostructure. It is shown that the sensitivity of proposed SPR sensors depends on the concentration of Bi2Se3 solution or the
more » ... ckness of the coated Bi2Se3 film. The optimised sensitivity (2929.1 nm/RIU) and figure of merit (33.45 RIU−1) have been obtained after three times drop-casting, and the enhancement sensitivity of proposed sensors is up to 51.97% compared to the traditional Au–SPR sensors. Meanwhile, the reflection spectrum is simulated by using the method of effective refractive index, and the reason for the increase of sensitivity is analysed theoretically. For researching the application of modified SPR sensor, heavy metal detection is employed to detect in the last part. Our proposed SPR sensors have potential applications in heavy metal detections and biosensing.
doi:10.1515/nanoph-2019-0439 fatcat:r45kypn6ynfeblhfqy7dzqsvra

Cerebroprotein hydrolysate‐I protects senescence‐induced by D‐galactose in PC12 cells and mice

Lin Zhu, Yingjuan Liu, Xiaolin Wu, Yuqian Ren, Qinghua Zhang, Leiming Ren, Yunliang Guo
2021 Food Science & Nutrition  
Leiming Ren: Conceptualization (supporting  ...  STAT3 is a transcription factor that plays a key role in cytokine and growth factor signaling, it has been shown that as a transcription factor of TERT, STAT3 can up-regulate TERT expression (Guo et al  ... 
doi:10.1002/fsn3.2333 fatcat:wiojzqqg5vdsfebbt3dylic4fe

In vivo99mTc-HYNIC-annexin V imaging of early tumor apoptosis in mice after single dose irradiation

Ming-fang Guo, Yaqing Zhao, Rong Tian, Lin Li, Leiming Guo, Feng Xu, Yong-mei Liu, Yong-bo He, Sen Bai, Jin Wang
2009 Journal of Experimental & Clinical Cancer Research  
Apoptosis is a major mode of hematological tumor death after radiation. Early detection of apoptosis may be beneficial for cancer adaptive treatment. 99mTc-HYNIC-annexinV has been reported as a promising agent for in vivo apoptosis imaging. The purpose of this study is to evaluate the feasibility of in vivo99mTc-HYNIC-annexinV imaging of radiation- induced apoptosis, and to investigate its correlation with radiosensitivity. Ten days after inoculation of tumor cells in the right upper limbs, the
more » ... mice were randomly divided into two groups. The imaging group (4 mice each level, 4 dose levels) was injected with 4-8 MBq 99mTc-HYNIC-annexinV 24 hours after irradiation and imaged 1 hr post-injection, and the mice were sacrificed immediately after imaging for biodistribution analysis of annexin V. The observation group (4 mice each level, 2 dose levels) was only observed for tumor regression post-radiation. The number of apoptotic cells in a tumor was estimated with TUNEL assay. The 99mTc-HYNIC-annexin V uptake in E14 lymphoma significantly increased as the radiation dose escalated from 0 to 8 Gy, and significantly correlated with the number of TUNEL-positive cells (r = 0.892, P < 0.001). The Annexin-V uptake and the number of TUNEL-positive cells in El4 lymphoma were significantly greater than those in S180 sarcoma. With 8 Gy, S180 sarcoma tumor showed scanty apoptosis and less shrinkage while El4 lymphoma showed remarkable apoptosis and complete remission. 99mTc-HYNIC-annexinV in vivo imaging is a feasible method to detect early radiation-induced apoptosis in different tumors, and might be predictive for radiation sensitivity.
doi:10.1186/1756-9966-28-136 pmid:19814783 pmcid:PMC2768695 fatcat:guc43fk24vf6javdfdaykdpekq

miR-494 Sensitizes Gastric Cancer Cells to TRAIL Treatment Through Downregulation of Survivin

Shuning Xu, Danyang Li, Tianyuan Li, Lei Qiao, Ke Li, Leiming Guo, Ying Liu
2018 Cellular Physiology and Biochemistry  
Background/Aims: TNF-related apoptosis-inducing ligand (TRAIL) is a novel and low-toxic anti-tumor drug used for various cancers. However, cancer cells usually develop mechanisms to acquire the resistance against TRAIL. Among these changes, dysregulation of microRNAs (miRNAs) usually occurs in cancer cells and is responsible for induction of drug resistance. Methods: Expression of miR-494 in gastric cancer tissues and cell lines was detected by quantitative reverse transcriptase real time PCR
more » ... RT-PCR) analysis. Effect of miR-494 on regulating the TRAIL sensitivity to gastric cancer cell lines was evaluated by MTT assays. Bioinformatics and luciferase reporter assays were used to confirm the regulation of miR-494 on survivin. Mitochondrial apoptosis pathway in gastric cancer cells was tested by western blot and flow cytometry analysis. Results: Obvious downregulation of miR-494 was observed in gastric cancer cells. Furthermore, we found that expression profile of miR-494 was associated with TRAIL-sensitivity in gastric cancer. Enforced expression of miR-494 was found to sensitize the gastric cancer cells to TRAIL-induced cytotoxicity. Mechanically, Luciferase reporter assays proved that survivin was the target of miR-494 in gastric cancer cells. Enforced expression of miR-494 decreased the expression of survivin, and thus promoted the TRAILinduced mitochondria collapse and apoptosis pathway. Conclusion: MiR-494/survivin axis represents a potential mechanism which is responsible for TRAIL resistance in gastric cancer cells. Increasing the miR-494 expression may serve as a novel therapeutic strategy to sensitize gastric cancer cells to TRAIL treatment.
doi:10.1159/000495867 fatcat:7s27ynx3b5hcvkmmjgppywj2w4
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