Publications by authors named "Qiang Zhong"

42 Publications

A Nomogram Model to Predict Prognosis of Patients With Genitourinary Sarcoma.

Front Oncol 2021 16;11:656325. Epub 2021 Apr 16.

Department of Urology, Institute of Urology, West China Hospital, Sichuan University, Chengdu, China.

Objectives: The aim of this study is to evaluate the significant factors influencing the overall survival (OS) and recurrence free survival (RFS) and make an attempt to develop a nomogram for predicting the prognosis of patients with genitourinary sarcoma (GS).

Methods: Data on adult GS from 1985 to 2010 were collected. The impact of clinical factors on OS and RFS were estimated by Kaplan-Meier (KM) analysis, and differences between groups were analyzed by the log-rank test. To establish a nomogram, all patients were randomly divided into a training set (n = 125) and a testing set (n = 63). Cox proportion hazard model was utilized to assess the prognostic effect of variables. Then, a nomogram was established to estimate 1-, 3-, and 5-year OS based on Cox regression model. Subsequently, the nomogram was validated by a training set and a validation set.

Results: A total of 188 patients were enrolled into our study. Male patients with bladder sarcoma had better OS rather than RFS when stratified by gender (P = 0.022). According to histological subtypes, patients with leiomyosarcoma (LMS) undergoing chemotherapy were associated with favorable OS (P = 0.024) and RFS (P = 0.001). Furthermore, LMS in kidney sarcoma were associated with lower recurrence rate in comparison to rhabdomyosarcoma (RMS) (P = 0.043). Margin status after surgical excision markedly influenced the OS and RFS of GS patients and negative margins presented optimal prognosis. Chemotherapy was associated with improved OS for patients without surgery (P = 0.029) and patients with positive margins (P = 0.026). Based on the multivariate analysis of the training cohort, age, gender, surgery status, histological subtype, and chemotherapy were included in our nomogram for prediction of OS. The nomogram had sufficient power with concordance index (C-index) of OS: 0.770, 95%CI: 0.760-0.772 and area under curve (AUC) of OS: 0.759, 95%CI: 0.658-0.859 in the training set and with C-index of OS: 0.741, 95%CI: 0.740-0.765, and AUC of OS: 0.744, 95%CI: 0.576-0.913 in the validation set.

Conclusions: Adults GS is a group of extremely rare tumors with poor prognosis. Of all histological types, LMS is sensitive to chemotherapy. We highlighted the cardinal role of surgical resection and the importance of achieving negative margins. We identified the efficacy of chemotherapy for patients with positive margins and those without surgery as well. A nomogram is validated as an effective tool predicting short-term outcomes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fonc.2021.656325DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8085422PMC
April 2021

Filamentous target segmentation of weft micro-CT image based on U-Net.

Micron 2021 Jul 27;146:102923. Epub 2021 Feb 27.

School of Mechanical and Electrical Engineering, Guangdong University of Technology (GDUT), China.

Textile fabrics inspection is an important part of textile manufacturing industry, more and more new inspections technologies are adopted for the application. Micro CT imaging technology is recently explored for textile material inspection. This paper proposed a method of weft micro-CT image segmentation based on U-Net, by using deep learning theory and X-ray micro-CT nondestructive detection technology to realize automatic segmentation of filamentous objects. Firstly, the weft micro-CT image was obtained by X-ray micro-CT scan, and then the segmentation target was manually divided. A high segmentation accuracy CT image segmentation dataset of textile materials was built for training the network model. Based on the original U-Net, through experimental exploration, the attention mechanism was introduced, and the encoder module, decoder module and loss function module were adjusted, so as to get a good segmentation effect. The experimental results show that the segmentation performance superiority of this proposed algorithm and the Dice similarity coefficient reaches 0.843. The method proposed in this paper provides a direction for the combination of deep learning technology and micro-CT technology in industrial detection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.micron.2020.102923DOI Listing
July 2021

Demographic, signs and symptoms, imaging characteristics of 2126 patients with COVID-19 pneumonia in the whole quarantine of Wuhan, China.

Clin Imaging 2021 Sep 23;77:169-174. Epub 2021 Feb 23.

Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Jie-Fang-Da-Dao 1095, Wuhan 430030, China. Electronic address:

Objective: The accurate knowledge of demographic, signs and symptoms, imaging characteristics of coronavirus disease 2019 (COVID-19) is essential for the accurate management of these patients. However, the claims between the previous papers are not always consistent and may even contradict each other, for example, some claims the virus infects more men than women in Wuhan. In this large-scale cohort study, we aimed to update the demographic, signs and symptoms, imaging characteristics of patients with COVID-19 in the whole quarantine of Wuhan, China.

Methods: A cohort of 2126 patients with a diagnosis of COVID-19 pneumonia (confirmed by real-time reverse transcriptase-polymerase chain reaction, RT-PCR) who were admitted to one hospital in Wuhan were retrospectively enrolled. Data were collected between January 13, 2020, and April 8, 2020, the end of Wuhan quarantine. Demographic, signs and symptoms, imaging characteristics were analyzed. CT imaging characteristics associated with respiratory failure or death were identified.

Results: Of the 2126 patients with COVID-19, 1051 (49.44%) were men and 1075 (50.56%) were women, 1933 (90.92%) have fever and 1328 (62.46%) have dry cough. The mean age was 57.43 years of age (range 1-95). The CT imaging findings were bilateral pneumonia (1883[88.57%]), unilateral pneumonia (243[11.43%]), ground-glass opacity (GGO) or consolidation (1175[55.27%]), pleural effusion (69[3.25%]). Patients with respiratory failure or death were more likely to have pleural effusion on CT than patients without respiratory failure or death (p < 0.05).

Conclusion: Men and women have been infected by SARS-CoV-2 in roughly equal numbers. Fever and cough are the most prevalent symptoms at disease onset in patients. Other prevalent symptoms include fatigue, and sputum production. COVID-19 patients with bilateral pneumonia and pleural effusion are more likely to develop respiratory failure or death.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.clinimag.2021.02.034DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7901270PMC
September 2021

Partial substitution of anthracite for coke breeze in iron ore sintering.

Sci Rep 2021 Jan 15;11(1):1540. Epub 2021 Jan 15.

School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083, People's Republic of China.

In the sintering of iron ores, the partial substitution of anthracite for coke breeze has been considered to be an effective way of reducing pollutant emissions and production cost. In this study, the basic characteristics of anthracite and coke breeze were compared and the sintering performance at different substitution ratios of anthracite for coke breeze was investigated. The porosity of anthracite is lower than that of coke breeze, but its density and combustion reactivity are higher. The substitution of anthracite for coke breeze has no influence on the granulation effect of the sintering blend. As the anthracite proportion increased, the sintering speed and productivity increased and the sintering yield and tumbler index decreased. As the substitution ratio increased from 0 to 60%, the melting temperature duration and the melt quantity index decreased from 2.59 to 2.03 min and from 3218.28 to 2405.75 °C·min, respectively, leading to insufficient sintering mineralization and bad sintering indexes. For an anthracite substitution ratio of 40%, the sintering speed, sintering productivity, sintering yield and tumbler index were 22.34 mm min, 1.49 t·(m h), 71.65% and 63.59%, respectively, which entirely satisfies the production requirements. Furthermore, hematite (FeO), calcium ferrite (CaO-FeO), and compound calcium ferrite (CaO-SiO-FeO) were the major mineral phases, which were embedded with an interwoven structure.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-021-80992-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7810896PMC
January 2021

Initial experiment of self-expanding metal ureteral stent in recurrent ureteral stenosis after kidney transplantation.

Am J Transplant 2021 05 4;21(5):1983-1984. Epub 2021 Jan 4.

Urology Department, Urology Research Institute, West China Hospital, Sichuan University, Chengdu, Sichuan, China.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/ajt.16444DOI Listing
May 2021

Development and Validation of a Prognostic Risk Score System for COVID-19 Inpatients: A Multi-Center Retrospective Study in China.

Engineering (Beijing) 2020 Nov 28. Epub 2020 Nov 28.

Department of Emergency, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.

Coronavirus disease 2019 (COVID-19) has become a worldwide pandemic. Hospitalized patients of COVID-19 suffer from a high mortality rate, motivating the development of convenient and practical methods that allow clinicians to promptly identify high-risk patients. Here, we have developed a risk score using clinical data from 1479 inpatients admitted to Tongji Hospital, Wuhan, China (development cohort) and externally validated with data from two other centers: 141 inpatients from Jinyintan Hospital, Wuhan, China (validation cohort 1) and 432 inpatients from The Third People's Hospital of Shenzhen, Shenzhen, China (validation cohort 2). The risk score is based on three biomarkers that are readily available in routine blood samples and can easily be translated into a probability of death. The risk score can predict the mortality of individual patients more than 12 d in advance with more than 90% accuracy across all cohorts. Moreover, the Kaplan-Meier score shows that patients can be clearly differentiated upon admission as low, intermediate, or high risk, with an area under the curve (AUC) score of 0.9551. In summary, a simple risk score has been validated to predict death in patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2); it has also been validated in independent cohorts.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.eng.2020.10.013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7695569PMC
November 2020

Nano-Silicate-Reinforced and SDF-1α-Loaded Gelatin-Methacryloyl Hydrogel for Bone Tissue Engineering.

Int J Nanomedicine 2020 24;15:9337-9353. Epub 2020 Nov 24.

Department of Orthopedics, Nanfang Hospital, Southern Medical University, Guangzhou, People's Republic of China.

Purpose: Autologous bone grafts are the gold standard for treating bone defects. However, limited bone supply and morbidity at the donor site restrict its extensive use. Therefore, developing bone graft materials as an alternative to autologous grafts has gained considerable attention. Injectable hydrogels endowed with osteogenic potential have the ability to fill irregular bone defects using minimally invasive procedures and have thus been attracting researchers' attention. However, from a clinical perspective, most fabrication methods employed for the current injectable osteogenic hydrogels are difficult and inconvenient. In the current study, we fabricated an injectable osteogenic hydrogel using a simple and convenient strategy.

Materials And Methods: Gelatin-methacryloyl (GelMA) pre-polymer was synthetized. Nano silicate (SN) and stromal cell-derived factor-1 alpha (SDF-1α) were introduced into the pre-polymer to achieve injectability, controlled release property, excellent osteogenic ability, and efficient stem cell homing.

Results: The GelMA-SN-SDF-1α demonstrated excellent injectability via a 17-G needle at room temperature. The loaded SDF-1α exhibited a long-term controlled release pattern and efficiently stimulated MSC migration and homing. The GelMA-SN-SDF-1α hydrogel amplified cell spreading, migration, osteogenic-related biomarker expression, and matrix mineralization. The GelMA-SN-SDF-1α hydrogel filled critical-sized calvaria defects in rats and demonstrated excellent bone regeneration ability, as assessed using micro-CT scanning and histomorphometric staining.

Conclusion: The GelMA-SN-SDF-1α hydrogel provides a simple and convenient strategy for the fabrication of injectable osteogenic graft materials.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2147/IJN.S270681DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7699450PMC
December 2020

Management of critically ill patients with COVID-19 in ICU: statement from front-line intensive care experts in Wuhan, China.

Ann Intensive Care 2020 Jun 6;10(1):73. Epub 2020 Jun 6.

Department of Critical Care Medicine, Shanghai Jiaotong University, School of Medicine, Ruijin Hospital North, No. 197 Ruijin 2nd Road, Huangpu District, Shanghai, 201801, China.

Background: The ongoing coronavirus disease 2019 (COVID-2019) pandemic has swept all over the world, posing a great pressure on critical care resources due to large number of patients needing critical care. Statements from front-line experts in the field of intensive care are urgently needed.

Methods: Sixteen front-line experts in China fighting against the COVID-19 epidemic in Wuhan were organized to develop an expert statement after 5 rounds of expert seminars and discussions to provide trustworthy recommendation on the management of critically ill COVID-19 patients. Each expert was assigned tasks within their field of expertise to provide draft statements and rationale. Parts of the expert statement are based on epidemiological and clinical evidence, without available scientific evidences.

Results: A comprehensive document with 46 statements are presented, including protection of medical personnel, etiological treatment, diagnosis and treatment of tissue and organ functional impairment, psychological interventions, immunity therapy, nutritional support, and transportation of critically ill COVID-19 patients. Among them, 5 recommendations were strong (Grade 1), 21 were weak (Grade 2), and 20 were experts' opinions. A strong agreement from voting participants was obtained for all recommendations.

Conclusion: There are still no targeted therapies for COVID-19 patients. Dynamic monitoring and supportive treatment for the restoration of tissue vascularization and organ function are particularly important.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13613-020-00689-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7275657PMC
June 2020

Clinical characteristics and risk factors associated with COVID-19 disease severity in patients with cancer in Wuhan, China: a multicentre, retrospective, cohort study.

Lancet Oncol 2020 07 29;21(7):893-903. Epub 2020 May 29.

Department of Immunology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Background: COVID-19 has spread globally. Epidemiological susceptibility to COVID-19 has been reported in patients with cancer. We aimed to systematically characterise clinical features and determine risk factors of COVID-19 disease severity for patients with cancer and COVID-19.

Methods: In this multicentre, retrospective, cohort study, we included all adult patients (aged ≥18 years) with any type of malignant solid tumours and haematological malignancy who were admitted to nine hospitals in Wuhan, China, with laboratory-confirmed COVID-19 between Jan 13 and March 18, 2020. Enrolled patients were statistically matched (2:1) with patients admitted with COVID-19 who did not have cancer with propensity score on the basis of age, sex, and comorbidities. Demographic characteristics, laboratory examinations, illness severity, and clinical interventions were compared between patients with COVID-19 with or without cancer as well as between patients with cancer with non-severe or severe COVID-19. COVID-19 disease severity was defined on admission on the basis of the WHO guidelines. Univariable and multivariable logistic regression, adjusted for age, sex, comorbidities, cancer type, tumour stage, and antitumour treatments, were used to explore risk factors associated with COVID-19 disease severity. This study was registered in the Chinese Clinical Trial Register, ChiCTR2000030807.

Findings: Between Jan 13 and March 18, 2020, 13 077 patients with COVID-19 were admitted to the nine hospitals in Wuhan and 232 patients with cancer and 519 statistically matched patients without cancer were enrolled. Median follow-up was 29 days (IQR 22-38) in patients with cancer and 27 days (20-35) in patients without cancer. Patients with cancer were more likely to have severe COVID-19 than patients without cancer (148 [64%] of 232 vs 166 [32%] of 519; odds ratio [OR] 3·61 [95% CI 2·59-5·04]; p<0·0001). Risk factors previously reported in patients without cancer, such as older age; elevated interleukin 6, procalcitonin, and D-dimer; and reduced lymphocytes were validated in patients with cancer. We also identified advanced tumour stage (OR 2·60, 95% CI 1·05-6·43; p=0·039), elevated tumour necrosis factor α (1·22, 1·01-1·47; p=0·037), elevated N-terminal pro-B-type natriuretic peptide (1·65, 1·03-2·78; p=0·032), reduced CD4+ T cells (0·84, 0·71-0·98; p=0·031), and reduced albumin-globulin ratio (0·12, 0·02-0·77; p=0·024) as risk factors of COVID-19 severity in patients with cancer.

Interpretation: Patients with cancer and COVID-19 were more likely to deteriorate into severe illness than those without cancer. The risk factors identified here could be helpful for early clinical surveillance of disease progression in patients with cancer who present with COVID-19.

Funding: China National Natural Science Foundation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/S1470-2045(20)30309-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7259911PMC
July 2020

Deterioration in quality of quick-frozen pork patties induced by changes in protein structure and lipid and protein oxidation during frozen storage.

Food Res Int 2020 07 3;133:109142. Epub 2020 Mar 3.

College of Food Science, Northeast Agricultural University, Harbin, Heilongjiang 150030, China. Electronic address:

Changes in quality, protein structure and oxidative reactions of quick-frozen pork patties (after -30 °C, 30 min), which were frozen at -8 °C, -18 °C, -25 °C, -8/-18 °C (stored at -8 °C for 5 days, then stored at -18 °C for 5 days, storage cycle continue until the end of storage period), -18/-25 °C (the same process as -8/-18 °C, temperature is -18 °C and -25 °C) for 0, 1, 2, 3, and 6 months were investigated. The a*-value, pH, water holding capacity and texture properties of pork patties were significantly changed (P < 0.05) at -8 °C, -8/-18 °C, -18/-25 °C after 1 month of frozen storage. The water redistribution within the patties was detected by LF-NMR analyses. After 6 months of frozen storage, the TBARS and carbonyl content of samples frozen at -8/-18 °C increased by 444% and 239%, respectively. Meanwhile, a decrease in fluorescence intensity reflected a decline in protein structure integrity. The association among quality, oxidative reactions and protein structure were elucidated by principal component analysis. The quality deterioration of the pork patties may be induced by the oxidative reaction and destruction of protein structural integrity during frozen storage.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.foodres.2020.109142DOI Listing
July 2020

Impact of metformin on survival outcome of esophageal squamous cell carcinomas patients undergoing surgical resection: a multicenter retrospective study.

J Thorac Dis 2020 Mar;12(3):830-838

Department of Thoracic Surgery, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510030, China.

Background: Diabetes mellitus is a recognized risk factor for esophageal squamous cell carcinomas (ESCC), and metformin is a recognized protective factor for some gastrointestinal tumors. But knowledge is limited regarding the effect of metformin on survival outcome of ESCC patients with type 2 diabetes mellitus (T2DM). We assessed the impact of post-diagnosis metformin use on overall survival (OS) and disease-free survival (DFS) in ESCC with T2DM undergoing surgical resection.

Methods: A retrospective analysis was performed on 3,523 patients with ESCC who met the study conditions after surgical resection. Log-rank and Cox regression models were used to evaluate the relationship between metformin and T2DM and ESCC survival rate, and adjusted according to age, gender, BMI, smoking, drinking and staging,

Results: Among included ESCC patients, 619 were associated with type 2 diabetes, while the remaining 2,904 were not associated with type 2 diabetes. The 5-year OS (28.43%) of patients with T2DM was significantly lower than that of patients without T2DM (32.75%), P=0.037. DFS in 5 years were 27.30% (with T2DM) and 31.75% (without T2DM) (P=0.030), respectively. Compared with patients without T2DM, patients with T2DM presented worse OS [adjusted risk ratio (HR) =1.19] and DFS (HRadj =1.17; P<0.001). Among the 619 patients with type 2 diabetes, 485 were treated with metformin and 134 were not treated with metformin. Patients treated with metformin had significantly improved OS [adjusted risk ratio (HR) =0.89; P=0.031) and DFS (HR =0.90; P=0.013).

Conclusions: T2DM was again associated with poorer survival in ESCC patients, and metformin may improve the prognosis of these patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/jtd.2019.12.98DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7138989PMC
March 2020

Effects of edible chitosan coating on Harbin red sausage storage stability at room temperature.

Meat Sci 2020 Jan 28;159:107919. Epub 2019 Aug 28.

College of Food Science, Northeast Agricultural University, Harbin, Heilongjiang 150030, China. Electronic address:

The effects of edible chitosan (CTS) coatings (0, 1, 2, and 3%) on Harbin red sausage storage stability at room temperature compared to vacuum packaging are discussed. The pH, moisture and L* of sausages decreased gradually, while the a*, TBARS, total aerobic bacteria (TAB) and lactic acid bacteria (LAB) increased significantly (P < 0.05) with the prolongation of storage time. In the same storage time, the storage stability was improved with the increase in the concentration of edible CTS coating, but there was no significant difference between 2% and 3% (P > 0.05). Although vacuum packaging can effectively maintain colour, moisture and reduce lipid oxidation, 2% CTS is outstanding in sustaining storage stability (pH and water distribution) and inhibition of microbial growth (TAB and LAB). In addition, no significant difference was observed between CTS coating and vacuum packaging on aroma and flavour (P > 0.05). In conclusion, CTS coating as edible packaging material can be used in meat products preservation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.meatsci.2019.107919DOI Listing
January 2020

Cellulose derived carbon nanofiber: A promising biochar support to enhance the catalytic performance of CoFeO in activating peroxymonosulfate for recycled dimethyl phthalate degradation.

Sci Total Environ 2019 Dec 31;694:133705. Epub 2019 Jul 31.

College of Biology and Environment, Nanjing Forestry University, Nanjing 210037, Jiangsu, People's Republic of China. Electronic address:

We prepared carbon nanofiber (CCNF) using cellulose as the carbon source in this study and utilized for the first time as the support to enhance the catalytic performance of the cobalt ferrite (CoFeO) for peroxymonosulfate (PMS) activation. The catalytic capability of the CoFeO/CCNF nanocomposites activated PMS was investigated through degrading dimethyl phthalate (DMP), a classical organic pesticide pollutant, in water media. The influence factors like CCNF content, nanocomposite and PMS dosage, DMP content, and pH value on the degradation speed were systematically investigated and analyzed. Since CoFeO is a spinel structured molecule which is magnetically separable, the reusability of the prepared CoFeO/CCNF nanocomposites under multiple cycles was also tested. Besides, the degradation intermediates during the catalytic process were also analyzed and identified by liquid chromatography-mass spectrometry (LC-MS) with a possible degradation mechanism. The results indicated that the prepared nanocomposite had promising catalytic capability in degrading DMP, in which the SO radicals played the main role as the active oxidation agent. Furthermore, the CoFeO/CCNF nanocomposites exhibited very good stability and reusability. The present study provides a clean biochar supported catalyst which could readily enhance the PMS activation efficiency for recycled decontamination of refractory organic pollutants in water media.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.scitotenv.2019.133705DOI Listing
December 2019

Comparing Models of Lateral Station-Keeping for Pitching Hydrofoils.

Biomimetics (Basel) 2019 Jul 22;4(3). Epub 2019 Jul 22.

Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, VA 22904, USA.

Fish must maneuver laterally to maintain their position in schools or near solid boundaries. Unsteady hydrodynamic models, such as the Theodorsen and Garrick models, predict forces on tethered oscillating hydrofoils aligned with the incoming flow. How well these models predict forces when bio-inspired hydrofoils are free to move laterally or when angled relative to the incoming flow is unclear. We tested the ability of five linear models to predict a small lateral adjustment made by a hydrofoil undergoing biased pitch oscillations. We compared the models to water channel tests in which air bushings gave a rigid pitching hydrofoil lateral freedom. What we found is that even with no fitted coefficients, linear models predict some features of the lateral response, particularly high frequency features like the amplitude and phase of passive heave oscillations. To predict low frequency features of the response, such as overshoot and settling time, we needed a semiempirical model based on tethered force measurements. Our results suggest that fish and fish-inspired vehicles could use linear models for some aspects of lateral station-keeping, but would need nonlinear or semiempirical wake models for more advanced maneuvers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/biomimetics4030051DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6784290PMC
July 2019

Multifunctional ZnO-porous carbon composites derived from MOF-74(Zn) with ultrafast pollutant adsorption capacity and supercapacitance properties.

J Colloid Interface Sci 2019 Oct 8;554:260-268. Epub 2019 Jul 8.

College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, Jiangsu, People's Republic of China. Electronic address:

In the present study, the ZnO-porous carbon (ZnO-C) composites were prepared by pyrolyzing MOF-74 (Zn) precursor at different pyrolysis temperatures. The ZnO-C composites were endowed with ultrafast organic dye adsorption capability and promising supercapacitance properties due to the existence of abundant pores within the composite structures. Having a surface area of 782.971 m/g and pore volume of 0.698 m/g, the composite pyrolyzed at 1000 °C (ZnO-C1000) exhibited the best performance for organic pollutant uptake. Specifically, 50 mg of ZnO-C1000 could remove all the Rhodamine B dye from 100 mL aqueous solution within 0.5 h even the dye concentration was as high as 40 mg/L. It was also shown that the ZnO-C composites could preserve their adsorption capability in a wide pH range, and keep promising dye adsorption stability after consecutive adsorption/desorption cycles. Furthermore, the ZnO-C900 exhibited a specific capacitance of 197.84 F/g as the supercapacitance electrode with good stability (∼97.8% capacitance retention after 1000 cycles). The overall results indicate that the prepared ZnO-C composites have multi-application potentials which can be utilized as efficient pollutant absorbents as well as electrode materials for supercapacitors.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jcis.2019.07.015DOI Listing
October 2019

Comparative characterization of putative chitin deacetylases from .

Biosci Biotechnol Biochem 2019 Jul 26;83(7):1306-1309. Epub 2019 Mar 26.

a Key Laboratory of Urban Agriculture (North China), Ministry of Agriculture , College of Biological Science and Engineering, Beijing University of Agriculture , Beijing , China.

Considering the challenges of controlling carmine spider mite and protecting pollinators, chitin deacetylase genes ( and ) of spider mite were characterized as group I, and were expressed in stage-specific pattern, which imply their role during development. The differences in sequences and structures between and honeybee CDAs offer possibilities to design new selective pesticides protecting pollinator honeybees.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/09168451.2019.1591264DOI Listing
July 2019

Adaption to stress via Pbs2 during Metarhizium rileyi conidia and microsclerotia development.

World J Microbiol Biotechnol 2018 Jul 3;34(8):107. Epub 2018 Jul 3.

Chongqing Engineering Research Center for Fungal Insecticide, School of Life Science, Chongqing University, Chongqing, 400030, People's Republic of China.

The high osmolarity glycerol (HOG) pathway plays important role in Metarhizium rileyi microsclerotia (MS) development. To investigate how M. rileyi transduce growth stress and regulate MS development via mitogen-activated protein kinase kinase (MAPKK) Pbs2, phenotypic characterization of the yeast Pbs2 homolog were performed. Expression of pbs2 peaked when MS formation occurred day 3 in liquid amended medium. Compared with wild-type and complemented strains, deletion mutant of pbs2 (Δpbs2) delayed dimorphic switch and vegetative growth, displayed sensitivities to various stress, and significantly reduced conidial (98%) and MS (40%) yields. Furthermore, transcription analysis showed that other genes of HOG signaling pathway were down-regulated in Δpbs2 mutants. Insect bioassays revealed that Δpbs2 mutants had decreased virulence levels in topical (24%) and injection (53%) bioassays. This study confirmed that Pbs2 play important roles in colony morphology, conidiation, stresses response and MS development in M. rileyi.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11274-018-2475-yDOI Listing
July 2018

Effect of perfluorooctane sulphonate-induced Kupffer cell activation on hepatocyte proliferation through the NF-κB/TNF-α/IL-6-dependent pathway.

Chemosphere 2018 Jun 23;200:283-294. Epub 2018 Feb 23.

Laboratory of Environment and Health, College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China. Electronic address:

Perfluorooctane sulfonate (PFOS), one member of polyfluoroalkyl chemicals (PFASs), persist in the environment and are found in relatively high concentrations in animal livers. PFOS has been shown to induce tumour of the liver in rats following chronic dietary administration. However, the molecular mechanisms involved in PFOS-induced hepatocellular hypertrophy are still not well characterized. In this study, male Sprague-Dawley rats were daily gavaged with PFOS (1 or 10 mg/kg body weight) for 28 days. Rat primary cultured Kupffer cells or hepatocytes were exposed to 100 μM PFOS for 0-48 h. Our results showed that PFOS exposure caused serious hepatocellular damage and obvious inflammatory cell infiltration and increased serum tumour necrosis factor-ɑ (TNF-α) and interleukin-6 (IL-6) levels. Particularly, PFOS exposure triggered Kupffer cell activation and significantly upregulated the expression of proliferating cell nuclear antigen (PCNA), c-Jun, c-MYC and Cyclin D1 (CyD1) in liver. In vitro, PFOS significantly induced production of TNF-α and IL-6 in Kupffer cells and increased PCNA, c-Jun, c-MYC and CyD1 expression in the primary hepatocytes co-cultured with Kupffer cells. However, Kupffer cell activation was mostly abolished by anti-TNF-α or anti-IL6 treatment. Furthermore, blockage of TNF-α and IL-6 significantly inhibited hepatocyte proliferation by gadolinium chloride (GdCl) pre-treatment in PFOS-treated mice and primary cultured Kupffer cells. On the other hand, NF-κB inhibitor (PDTC) and c-Jun amino-terminal kinase (JNK) inhibitor (SP600125) significantly inhibited production of PFOS-induced TNF-α and IL-6. Taken together, these data suggest that PFOS induces Kupffer cell activation, leading to hepatocyte proliferation by through the NF-κB/TNF-ɑ/IL-6-dependent pathway.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chemosphere.2018.02.137DOI Listing
June 2018

Perfluorooctane sulphonate induces oxidative hepatic damage via mitochondria-dependent and NF-κB/TNF-α-mediated pathway.

Chemosphere 2018 Jan 15;191:1056-1064. Epub 2017 Aug 15.

Laboratory of Environment and Health, College of Life Sciences, University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China. Electronic address:

Perfluorooctane sulphonate (PFOS) has been reported to accumulate in liver and cause damage. The molecular mechanism of the PFOS-induced hepatotoxicity has not been completely elucidated. The aim of the present study was to investigate whether PFOS-induced oxidative stress plays an important role in liver damage, and if so, what pathway it undergoes for the mechanism of its toxicological action. Male Sprague-Dawley (SD) rats were orally administrated with PFOS at single dose of 1 or 10 mg/kg body weight for 28 consecutive days. Increased serum levels of liver enzymes and abnormal ultra structural changes were observed in the PFOS-exposed rats. Particularly, PFOS exposure significantly increased intracellular reactive oxygen species (ROS) and nitric oxide (NO) production, but weakened intracellular antioxidant defence by inhibiting catalase and superoxide dismutase activities. Signal transduction studies showed that PFOS exposure significantly elevated inducible nitric oxide synthase (iNOS), Bax, cytochrome c, cleaved caspase-9 and cleaved caspase-3, indicating the mitochondria-dependent apoptotic pathway was activated. On the other hand, significant alterations of the PFOS-induced protein expression of NF-κB and IκBα in association with an enhanced level of TNF-α were observed. Taken together, these results indicate that mitochondria play an important role in PFOS-induced hepatotoxicity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chemosphere.2017.08.070DOI Listing
January 2018

A Nonlinear Dynamics-Based Estimator for Functional Electrical Stimulation: Preliminary Results From Lower-Leg Extension Experiments.

IEEE Trans Neural Syst Rehabil Eng 2017 12 7;25(12):2365-2374. Epub 2017 Sep 7.

Miniature inertial measurement units (IMUs) are wearable sensors that measure limb segment or joint angles during dynamic movements. However, IMUs are generally prone to drift, external magnetic interference, and measurement noise. This paper presents a new class of nonlinear state estimation technique called state-dependent coefficient (SDC) estimation to accurately predict joint angles from IMU measurements. The SDC estimation method uses limb dynamics, instead of limb kinematics, to estimate the limb state. Importantly, the nonlinear limb dynamic model is formulated into state-dependent matrices that facilitate the estimator design without performing a Jacobian linearization. The estimation method is experimentally demonstrated to predict knee joint angle measurements during functional electrical stimulation of the quadriceps muscle. The nonlinear knee musculoskeletal model was identified through a series of experiments. The SDC estimator was then compared with an extended kalman filter (EKF), which uses a Jacobian linearization and a rotation matrix method, which uses a kinematic model instead of the dynamic model. Each estimator's performance was evaluated against the true value of the joint angle, which was measured through a rotary encoder. The experimental results showed that the SDC estimator, the rotation matrix method, and EKF had root mean square errors of 2.70°, 2.86°, and 4.42°, respectively. Our preliminary experimental results show the new estimator's advantage over the EKF method but a slight advantage over the rotation matrix method. However, the information from the dynamic model allows the SDC method to use only one IMU to measure the knee angle compared with the rotation matrix method that uses two IMUs to estimate the angle.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1109/TNSRE.2017.2748420DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5793227PMC
December 2017

The high osmotic response and cell wall integrity pathways cooperate to regulate morphology, microsclerotia development, and virulence in Metarhizium rileyi.

Sci Rep 2016 12 12;6:38765. Epub 2016 Dec 12.

Chongqing Engineering Research Center for Fungal Insecticide, School of Life Science, Chongqing University, Chongqing 400030, People's Republic of China.

Microsclerotia (MS) formation was successfully induced in Metarhizium rileyi under changing liquid culture conditions. Mitogen-activated protein kinases (MAPKs) play important roles in fungal development and in coordinating many stress responses. To investigate how M. rileyi transduces growth stress and regulates MS differentiation, we characterized the roles of two MAPKs, Hog1- and Slt2-type orthologues, in M. rileyi. Compared with the wild-type strain, the deletion mutants of Mrhog1 (ΔMrhog1) and Mrslt2 (ΔMrslt2) delayed germination and vegetative growth, displayed sensitivities to various stress, and produced morphologically abnormal clones. The ΔMrhog1 and ΔMrslt2 mutants significantly reduced conidial (42-99%) and MS (96-99%) yields. A transcriptional analysis showed that the two MAPKs regulate MS development in a cooperative manner. Insect bioassays revealed that ΔMrhog1 and ΔMrslt2 had decreased virulence levels in topical (36-56%) and injection (78-93%) bioassays. Our results confirmed the roles of MrHog1 and MrSlt2 in sensing growth-related stress and in regulating MS differentiation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/srep38765DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5150533PMC
December 2016

Candidate genes and pathogenesis investigation for sepsis-related acute respiratory distress syndrome based on gene expression profile.

Biol Res 2016 Apr 18;49:25. Epub 2016 Apr 18.

Department of Emergency and Intensive Care Unit, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan, 430030, China.

Background: Acute respiratory distress syndrome (ARDS) is a potentially devastating form of acute inflammatory lung injury as well as a major cause of acute respiratory failure. Although researchers have made significant progresses in elucidating the pathophysiology of this complex syndrome over the years, the absence of a universal detail disease mechanism up until now has led to a series of practical problems for a definitive treatment. This study aimed to predict some genes or pathways associated with sepsis-related ARDS based on a public microarray dataset and to further explore the molecular mechanism of ARDS.

Results: A total of 122 up-regulated DEGs and 91 down-regulated differentially expressed genes (DEGs) were obtained. The up- and down-regulated DEGs were mainly involved in functions like mitotic cell cycle and pathway like cell cycle. Protein-protein interaction network of ARDS analysis revealed 20 hub genes including cyclin B1 (CCNB1), cyclin B2 (CCNB2) and topoisomerase II alpha (TOP2A). A total of seven transcription factors including forkhead box protein M1 (FOXM1) and 30 target genes were revealed in the transcription factor-target gene regulation network. Furthermore, co-cited genes including CCNB2-CCNB1 were revealed in literature mining for the relations ARDS related genes.

Conclusions: Pathways like mitotic cell cycle were closed related with the development of ARDS. Genes including CCNB1, CCNB2 and TOP2A, as well as transcription factors like FOXM1 might be used as the novel gene therapy targets for sepsis related ARDS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s40659-016-0085-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4835843PMC
April 2016

Structural basis of H2A.Z recognition by SRCAP chromatin-remodeling subunit YL1.

Nat Struct Mol Biol 2016 Apr 14;23(4):317-23. Epub 2016 Mar 14.

National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.

Histone variant H2A.Z, a universal mark of dynamic nucleosomes flanking gene promoters and enhancers, is incorporated into chromatin by SRCAP (SWR1), an ATP-dependent, multicomponent chromatin-remodeling complex. The YL1 (Swc2) subunit of SRCAP (SWR1) plays an essential role in H2A.Z recognition, but how it achieves this has been unclear. Here, we report the crystal structure of the H2A.Z-binding domain of Drosophila melanogaster YL1 (dYL1-Z) in complex with an H2A.Z-H2B dimer at 1.9-Å resolution. The dYL1-Z domain adopts a new whip-like structure that wraps over H2A.Z-H2B, and preferential recognition is largely conferred by three residues in loop 2, the hyperacidic patch and the extended αC helix of H2A.Z. Importantly, this domain is essential for deposition of budding yeast H2A.Z in vivo and SRCAP (SWR1)-catalyzed histone H2A.Z replacement in vitro. Our studies distinguish YL1-Z from known H2A.Z chaperones and suggest a hierarchical mechanism based on increasing binding affinity facilitating H2A.Z transfer from SRCAP (SWR1) to the nucleosome.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/nsmb.3190DOI Listing
April 2016

Twist1 is a potential prognostic marker for colorectal cancer and associated with chemoresistance.

Am J Cancer Res 2015 15;5(6):2000-11. Epub 2015 May 15.

Department of General Surgery, Shunde First People's Hospital Affiliated to Southern Medical University China.

Twist1 is a highly conserved basic helix-loophelix transcription factor, and has been shown to play an important role in carcinogenesis of many tumors including colorectal cancer (CRC). Here we aimed to investigate the role of Twist1 in the clinical significance and chemoresistance in CRC. In this study, we examined the correlation between Twist1 expression and clinicopathological characteristics using immunohistochemistry in patients with CRC. The molecular mechanisms of Twist1 expression and its effects on chemosensitivity to 5-Fluorouracil and oxaliplatin were also explored by MTT assay, colony forming assay, flow cytometry assay. The results indicate that Twist1 is overexpressed in cancer tissue, and its positive expression are related to histological grade (P=0.004), T-stage (P=0.033), N-stage (P=0.000), M-stage (P=0.040), TNM stage (P=0.002) and recurrence (P=0.023). Moreover, positive Twist1 expression is correlated with poor overall survival in CRC patients (P<0.0001), and is a significant independent prognostic indicator. In addition, we show that knockdown of Twist1 inhibits proliferation, and increased the percentage of apoptotic cells of CRC cell lines. Our findings suggest that Twist1 promotes proliferation and chemoresistance of CRC cells. Twist1 may be a potential prognostic marker and a molecular target for therapies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4529619PMC
August 2015

A novel pharmacological strategy by PTEN inhibition for improving metabolic resuscitation and survival after mouse cardiac arrest.

Am J Physiol Heart Circ Physiol 2015 Jun 20;308(11):H1414-22. Epub 2015 Mar 20.

Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital & Health Sciences System, Chicago, Illinois;

Sudden cardiac arrest (SCA) is a leading cause of death in the United States. Despite return of spontaneous circulation, patients die due to post-SCA syndrome that includes myocardial dysfunction, brain injury, impaired metabolism, and inflammation. No medications improve SCA survival. Our prior work suggests that optimal Akt activation is critical for cooling protection and SCA recovery. Here, we investigate a small inhibitor of PTEN, an Akt-related phosphatase present in heart and brain, as a potential therapy in improving cardiac and neurological recovery after SCA. Anesthetized adult female wild-type C57BL/6 mice were randomized to pretreatment of VO-OHpic (VO) 30 min before SCA or vehicle control. Mice underwent 8 min of KCl-induced asystolic arrest followed by CPR. Resuscitated animals were hemodynamically monitored for 2 h and observed for 72 h. Outcomes included heart pressure-volume loops, energetics (phosphocreatine and ATP from (31)P NMR), protein phosphorylation of Akt, GSK3β, pyruvate dehydrogenase (PDH) and phospholamban, circulating inflammatory cytokines, plasma lactate, and glucose as measures of systemic metabolic recovery. VO reduced deterioration of left ventricular maximum pressure, maximum rate of change in the left ventricular pressure, and Petco2 and improved 72 h neurological intact survival (50% vs. 10%; P < 0.05). It reduced plasma lactate, glucose, IL-1β, and Pre-B cell colony enhancing factor, while increasing IL-10. VO increased phosphorylation of Akt and GSK3β in both heart and brain, and cardiac phospholamban phosphorylation while reducing p-PDH. Moreover, VO improved cardiac bioenergetic recovery. We concluded that pharmacologic PTEN inhibition enhances Akt activation, improving metabolic, cardiovascular, and neurologic recovery with increased survival after SCA. PTEN inhibitors may be a novel pharmacologic strategy for treating SCA.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1152/ajpheart.00748.2014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4451301PMC
June 2015

Structure-based grafting, mutation, and optimization of peptide inhibitors to fit in the active pocket of human secreted phospholipase A2: find new use of old Peptide agents with anti-inflammatory activity.

Chem Biol Drug Des 2015 Apr 25;85(4):418-26. Epub 2014 Sep 25.

Department of ICU, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.

Phospholipase A2 (PLA2) is a key enzyme in the production of diverse mediators of inflammatory conditions, which possesses an open active pocket that is physicochemically compatible with a variety of small-molecule substrates and peptide inhibitors. Although various peptides and peptide analogues have been identified to have inhibitory activity against PLA2 originated from animals and plants, only very few were designed for human secreted PLA2 (hsPLA2), an attractive target of inflammatory arthritis. Considering that the catalytic domains of PLA2 family members across different species are highly conserved in primary sequence, advanced structure, and biological function, in this study, we proposed a synthetic pipeline to implement structure-based grafting, mutation, and optimization of peptide ligands from the snake PLA2-peptide complex crystal structures into the active pocket of apo hsPLA2 structure to computationally generate a large number of potential peptide inhibitors for hsPLA2, and the hsPLA2 inhibitory potency of few highly promising candidates arising from the theoretical analysis was determined. As might be expected, three peptides FLSFK, FLVYK, and FISYR showed relatively high inhibitory capability against hsPLA2, and other three ALSYK, LVFYA, and KGAILGFM were also modestly potent as they can suppress the enzymatic activity with observable doses. Further, the designed peptide FLVYK with highest potency was carried out with structure-guided modification based on its atomic interactions with hsPLA2 using the computationally modeled structure data, consequently resulting in a dual-point mutant ELIYK with significantly increased activity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/cbdd.12424DOI Listing
April 2015

Posterior fossa decompression combined with resection of the cerebellomedullary fissure membrane and expansile duraplasty: a radical and rational surgical treatment for Arnold-Chiari type I malformation.

Cell Biochem Biophys 2014 Dec;70(3):1817-21

Department of Neurosurgery, The Affiliated Futain Hospital of Guangdong Medical College, The Fourth Hospital of Shenzhen, Shenzhen, P.O. 0086 518033, Guangdong, People's Republic of China,

This study aims to introduce a new surgical procedure for the treatment of Arnold-Chiari type I malformation (ACM-1) and to compare its effectiveness with the techniques described in previous studies. We performed the following procedures: foramen magnum decompression combined with the removal of both the atlanto-occipital membrane, extended resection of the cerebellomedullary fissure arachnoid membrane, and artificial duraplasty to enlarge the membranic posterior fossa without resecting the cerebellar tonsils and syringosubarachnoid shunting. There were 21 ACM-1 patients: 12 cases had osteo-compression on the cerebellar hemisphere, 18 cases had thickened adhered fabric ring that stretched from arachnoid membrane to cerebellar hemisphere, and 15 cases with syringomyelia. The patients were followed up for 6 months to 3 years after the surgery. All patients showed a remarkable recovery of syringomyelia. There were no morbidity or death related to the surgery. Most of ACM-1 patients, the osteo- and membrane compression on cerebellar hemisphere and tonsil were observed during the operation. Therefore, decompression of foramen magnum and posterior craniocervical combined with the removal of cerebellomedullary fissure arachnoid membrane and placement of an artificial dural graft should be considered as a comprehensive option of minimally invasive surgery and rational and radical treatment of ACM-1. Our experience showed that, by using our procedure, shunting becomes no longer necessary in the treatment of ACM-1-associated syringomyelia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12013-014-0135-xDOI Listing
December 2014

Autonomous motion and temperature-controlled drug delivery of Mg/Pt-poly(N-isopropylacrylamide) Janus micromotors driven by simulated body fluid and blood plasma.

ACS Appl Mater Interfaces 2014 Jun 6;6(12):9897-903. Epub 2014 Jun 6.

State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology , Wuhan 430070, People's Republic of China.

In this work, we have demonstrated the autonomous motion of biologically-friendly Mg/Pt-Poly(N-isopropylacrylamide) (PNIPAM) Janus micromotors in simulated body fluids (SBF) or blood plasma without any other additives. The pit corrosion of chloride anions and the buffering effect of SBF or blood plasma in removing the Mg(OH)2 passivation layer play major roles for accelerating Mg-H2O reaction to produce hydrogen propulsion for the micromotors. Furthermore, the Mg/Pt-PNIPAM Janus micromotors can effectively uptake, transport, and temperature-control-release drug molecules by taking advantage of the partial surface-attached thermoresponsive PNIPAM hydrogel layers. The PNIPAM hydrogel layers on the micromotors can be easily replaced with other responsive polymers or antibodies by the surface modification strategy, suggesting that the as-proposed micromotors also hold a promising potential for separation and detection of heavy metal ions, toxicants, or proteins.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/am502729yDOI Listing
June 2014

TAT-protein blockade during ischemia/reperfusion reveals critical role for p85 PI3K-PTEN interaction in cardiomyocyte injury.

PLoS One 2014 21;9(4):e95622. Epub 2014 Apr 21.

Program in Advanced Resuscitation Medicine, Center for Cardiovascular Research, and Department of Emergency Medicine, University of Illinois Hospital and Health Sciences System, Chicago, Illinois, United States of America.

Recent work shows that cooling protection after mouse cardiac arrest and cardiomyocyte ischemia is mediated by Akt activation. The PI3K p85 subunit can either augment or inhibit Akt activation depending on its binding to p110 or PTEN respectively. To further clarify the role of PI3K p85 in cardioprotection, we studied novel TAT-p85 fusion proteins that selectively inhibit PI3K p85 binding. We hypothesized that TAT fused p85 lacking the PTEN binding site (TAT-ΔPTEN p85) would enhance Akt phosphorylation to afford cardioprotection. Conversely, TAT fused p85 lacking the p110 binding site (TAT-Δp110p85) would decrease Akt phosphorylation and abrogate cardioprotection. Microscopy and Western blot analysis demonstrated that TAT fusion protein was transduced into cardiomyocytes within 5 min and remained more than 2 h. Inhibition of PI3K/Akt by TAT-Δp110 p85 significantly increased cell death from 44.6±2.7% to 92.5±3.4% after simulated ischemia and reperfusion. By contrast, PTEN inhibition using TAT-ΔPTEN p85 decreased cell death to 11.9±5.3%, a similar level of cardioprotection seen with past cooling studies. Additional studies with the small molecule PTEN inhibitor VO-OHpic confirmed that PTEN inhibition was highly protective against cell death induced by ischemia and reperfusion. We conclude that blockade of p85-PTEN interaction and PTEN inhibition may be promising strategies for rescuing the heart from ischemia and reperfusion injury.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0095622PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3994094PMC
January 2015

Upregulation of sestrin-2 expression via P53 protects against 1-methyl-4-phenylpyridinium (MPP+) neurotoxicity.

J Mol Neurosci 2013 Nov;51(3):967-75

Sestrin-2 (SESN2) is a conserved antioxidant protein that is activated upon oxidative stress and protects cells against reactive oxygen species (ROS). However, the role of SESN2 in neurodegenerative diseases, especially in Parkinson's disease (PD), has not yet been elucidated. In this study, we found that expression of SESN2 is elevated in the midbrain of patients with PD. Moreover, in vitro experiments display that the drug 1-methyl-4-phenylpyridinium (MPP+) induces the expression of SESN2 in SH-SY5Y cells in a time- and dose-dependent manner. Our results show that p53 is activated by MPP+. Importantly, inhibition of p53 using small RNA interferences abolishes the increased SESN2 levels induced by MPP+, suggesting that the inductive effect of MPP+ on SESN2 is mediated by p53. Furthermore, knockdown of SESN2 using small RNA interferences promotes MPP+-related neurotoxicity by attenuating oxidative stress, mitochondrial dysfunction, and apoptosis. All these data imply that the induction of SESN2 produces a protective effect in PD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12031-013-0081-xDOI Listing
November 2013
-->