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Coupling of an Au@AgPt nanozyme array with an micrococcal nuclease-specific responsiveness strategy for colorimetric/SERS sensing of Staphylococcus aureus in patients with sepsis
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作者 Xueqin Huang Yingqi Yang +12 位作者 Hanlin Zhou Liping Hu Annan Yang Hua Jin Biying Zheng Jiang Pi Jun Xu Pinghua Sun Huai-Hong Cai Xujing Liang Bin Pan Junxia Zheng Haibo Zhou 《Journal of Pharmaceutical Analysis》 2025年第2期389-400,共12页
Rapid and ultrasensitive detection of pathogen-associated biomarkers is vital for the early diagnosis and therapy of bacterial infections.Herein,we developed a close-packed and ordered Au@AgPt array coupled with a cas... Rapid and ultrasensitive detection of pathogen-associated biomarkers is vital for the early diagnosis and therapy of bacterial infections.Herein,we developed a close-packed and ordered Au@AgPt array coupled with a cascade triggering strategy for surface-enhanced Raman scattering(SERS)and colorimetric identification of the Staphylococcus aureus biomarker micrococcal nuclease(MNase)in serum samples.The trimetallic Au@AgPt nanozymes can catalyze the oxidation of 3,3’,5,5’-tetramethylbenzidine(TMB)molecules to SERS-enhanced oxidized TMB(oxTMB),accompanied by the color change from colorless to blue.In the presence of S.aureus,the secreted MNase preferentially cut the nucleobase AT-rich regions of DNA sequences on magnetic beads(MBs)to release alkaline phosphatase(ALP),which subsequently mediated the oxTMB reduction for inducing the colorimetric/SERS signal fade away.Using this“on-to-off”triggering strategy,the target S.aureus can be recorded in a wide linear range with a limit of detection of 38 CFU/mL in the colorimetric mode and 6 CFU/mL in the SERS mode.Meanwhile,the MNase-mediated strategy characterized by high specificity and sensitivity successfully discriminated between patients with sepsis(n=7)and healthy participants(n=3),as well as monitored the prognostic progression of the disease(n=2).Overall,benefiting from highly active and dense“hot spot”substrate,MNase-mediated cascade response strategy,and colorimetric/SERS dual-signal output,this methodology will offer a promising avenue for the early diagnosis of S.aureus infection. 展开更多
关键词 Au@AgPt nanoarrays Surface-enhanced Raman scattering COLORIMETRY Cascade response strategy MNase
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Fluorescent Double Network Hydrogels with Ionic Responsiveness and High Mechanical Properties for Visual Detection
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作者 郑湾 LIU Lerong +5 位作者 Lü Hanlin WANG Yuhang LI Feihu ZHANG Yixuan 陈艳军 WANG Yifeng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期487-496,共10页
We developed a fluorescent double network hydrogel with ionic responsiveness and high mechanical properties for visual detection.The nanocomposite hydrogel of laponite and polyacrylamide serves as the first network,wh... We developed a fluorescent double network hydrogel with ionic responsiveness and high mechanical properties for visual detection.The nanocomposite hydrogel of laponite and polyacrylamide serves as the first network,while the ionic cross-linked hydrogel of terbium ions and sodium alginate serves as the second network.The double-network structure,the introduction of nanoparticles and the reversible ionic crosslinked interactions confer high mechanical properties to the hydrogel.Terbium ions are not only used as the ionic cross-linked points,but also used as green emitters to endow hydrogels with fluorescent properties.On the basis of the “antenna effect” of terbium ions and the ion exchange interaction,the fluorescence of the hydrogels can make selective responses to various ions(such as organic acid radical ions,transition metal ions) in aqueous solutions,which enables a convenient strategy for visual detection toward ions.Consequently,the fluorescent double network hydrogel fabricated in this study is promising for use in the field of visual sensor detection. 展开更多
关键词 visual detection ionic responsiveness fluorescent hydrogels double network hydrogels mechanical property
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Rosmarinic acid improves tracheal smooth muscle responsiveness and lung pathological changes in ovalbumin-sensitized rats
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作者 Vahideh Abbasnia Mohsen Foadoddini +2 位作者 Delaram Eslimi Esfahani Mohammad Reza Khazdair Shahrbanoo Oryan 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第3期100-105,共6页
Objective:To evaluate the effect of rosmarinic acid on tracheal smooth muscle responsiveness and lung pathological changes in ovalbumin-sensitized rats.Methods:Rats were randomly divided into six groups:the control gr... Objective:To evaluate the effect of rosmarinic acid on tracheal smooth muscle responsiveness and lung pathological changes in ovalbumin-sensitized rats.Methods:Rats were randomly divided into six groups:the control group,the asthmatic group,and the asthmatic groups treated with dexamethasone(1 mg/kg;oral gavage)or three doses of rosmarinic acid(0.5,1,and 2 mg/kg;oral gavage).For induction of asthma,rats received intraperitoneal injections and inhalation of ovalbumin.After 21 days,bronchoalveolar lavage fluid and lung samples were collected for histopathological analyses.Moreover,total and differential white blood cell counts were determined.Results:The rosmarinic acid-treated group had significantly lower tracheal smooth muscle responses to methacholine than the asthmatic group.In addition,rosmarinic acid reduced white blood cell count and the percentages of eosinophils,monocytes,and neutrophils while increasing the percentage of lymphocytes.Ovalbumin-induced lung pathological changes were significantly improved by treatment with rosmarinic acid.Conclusions:Rosmarinic acid improves tracheal smooth muscle responsiveness and lung pathological changes in ovalbumin-sensitized rats. 展开更多
关键词 Rosmarinic acid ASTHMA OVALBUMIN Tracheal responsiveness Inflammation White blood cell
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Transcriptomic analysis in Anemone flaccida rhizomes reveals ancillary pathway for triterpene saponins biosynthesis and differential responsiveness to phytohormones 被引量:8
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作者 MO Guo-Yan HUANG Fang +6 位作者 FANG Yin HAN Lin-Tao Kayla K.Pennerman BU Li-Jing DU Xiao-Wei Joan W.Bennett YIN Guo-Hua 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2019年第2期131-144,共14页
Anemone flaccida Fr. Schmidt is a perennial medicinal herb that contains pentacyclic triterpenoid saponins as the major bioactive constituents. In China, the rhizomes are used as treatments for a variety of ailments i... Anemone flaccida Fr. Schmidt is a perennial medicinal herb that contains pentacyclic triterpenoid saponins as the major bioactive constituents. In China, the rhizomes are used as treatments for a variety of ailments including arthritis. However, yields of the saponins are low, and little is known about the plant's genetic background or phytohormonal responsiveness. Using one-quarter of the 454 pyrosequencing information from the Roche GS FLX Titanium platform, we performed a transcriptomic analysis to identify 157 genes putatively encoding 26 enzymes involved in the synthesis of the bioactive compounds. It was revealed that there are two biosynthetic pathways of triterpene saponins in A. flaccida. One pathway depends on β-amyrin synthase and is similar to that found in other plants. The second, subsidiary("backburner") pathway is catalyzed by camelliol C synthase and yields β-amyrin as minor byproduct. Both pathways used cytochrome P450-dependent monooxygenases(CYPs) and family 1 uridine diphosphate glycosyltransferases(UGTs) to modify the triterpenoid backbone. The expression of CYPs and UGTs were quite different in roots treated with the phytohormones methyl jasmonate, salicylic acid and indole-3-acetic acid. This study provides the first large-scale transcriptional dataset for the biosynthetic pathways of triterpene saponins and their phytohormonal responsiveness in the genus Anemone. 展开更多
关键词 ANEMONE flaccida Fr.Schmidt TRITERPENOID SAPONINS Biosynthetic pathways Transcriptomic analysis Phytohormonal responsiveness
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Modes of Action of Phytochromes in Establishing Different Phototropic Responsiveness of Maize Coleoptiles 被引量:3
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作者 刘玉军 赵南明 《Acta Botanica Sinica》 CSCD 2001年第9期923-928,共6页
Previous studies have examined the effects of red light (R) on phototropism of maize ( Zea mays L. cv. Royaldent Hit 85) coleoptiles. The R effect on time-dependent phototropism (TDP) was further studied by characteri... Previous studies have examined the effects of red light (R) on phototropism of maize ( Zea mays L. cv. Royaldent Hit 85) coleoptiles. The R effect on time-dependent phototropism (TDP) was further studied by characterizing its fluence-response relationship. The results showed the R effect was a low-fluence-response, unlike those on pulse-induced phototropisms that show a very-low-fluence-response mode. A subsequent pulse of far-red light (FR) could reverse the R effect. TDP responsiveness, however, recovered as the following FR was extended, The FR-dependent increase in TDP responsiveness was obtained even coleoptiles were pretreated only with FR. It suggested that TDP responsiveness could also be established in response to a FR signal. The fluence-response relationship for the effect of FR was then investigated. The effect of FR depended on the time of irradiation and required high photon fluences. Because reciprocity was invalid at the higher fluence range, the effect of FR would be a high-irradiance-response mode. Relation between phytochrome action modes and possible multiple pathways for phototropic signal transduction was analyzed based on the experiment results. 展开更多
关键词 far-red light high irradiance response PHOTOTROPISM PHYTOCHROME phytochrome action mode maize coleoptile
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Performance of the Autism Spectrum Rating Scale and Social Responsiveness Scale in Identifying Autism Spectrum Disorder Among Cases of Intellectual Disability 被引量:7
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作者 Chunpei Li Hao Zhou +5 位作者 Tianqi Wang Shasha Long Xiaonan Du Xiu Xu Weili Yan Yi Wang 《Neuroscience Bulletin》 SCIE CAS CSCD 2018年第6期972-980,共9页
The Autism Spectrum Rating Scale(ASRS) and the Social Responsiveness Scale(SRS) have been widely used for screening autism spectrum disorder(ASD) in the general population during epidemiological studies, but studies o... The Autism Spectrum Rating Scale(ASRS) and the Social Responsiveness Scale(SRS) have been widely used for screening autism spectrum disorder(ASD) in the general population during epidemiological studies, but studies of individuals with intellectual disability(ID) are quite limited. Therefore, we recruited the parents/caregivers of 204 ASD cases, 71 ID cases aged 6–18 years from special education schools, and 402 typically developing(TD) children in the same age span from a communitybased population to complete the ASRS and SRS. The results showed that the ID group scored significantly lower on total and subscale scores than the ASD group on both scales(P \ 0.05) but higher than TD children(P \ 0.05).Receiver operating characteristic analyses demonstrated a similar fair performance in discriminating ASD from ID with the ASRS(area under the curve(AUC) = 0.709,sensitivity = 77.0%, specificity = 52.1%, positive predictive value(PPV) = 82.2%) and the SRS(AUC = 0.742,sensitivity = 59.8%, specificity = 77.5%, PPV = 88.4%).The results showed that individuals with ID had clear autistic traits and discriminating ASD from ID cases was quite challenging, while assessment tools such as ASRS and SRS, help to some degree. 展开更多
关键词 Autism spectrum disorder Intellectual disability Screening accuracy Autism Spectrum Rating Scale Social responsiveness Scale
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Responsiveness and minimal clinically important difference of the Chinese version of the Low Vision Quality of Life Questionnaire after cataract surgery 被引量:4
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作者 Wen-Wen Xue Pei Zhang Hai-Dong Zou 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第3期504-509,共6页
AIM: To investigate the Chinese version of the Low Vision Quality of Life Questionnaire(CLVQOL) as an instrument for obtaining clinically important changes after cataract surgery.METHODS: Patients underwent cataract s... AIM: To investigate the Chinese version of the Low Vision Quality of Life Questionnaire(CLVQOL) as an instrument for obtaining clinically important changes after cataract surgery.METHODS: Patients underwent cataract surgery in Shanghai General Hospital, Shanghai Jiao Tong University, who fit the inclusion criteria were recruited. Two CLVQOLs were administered, including a preoperative CLVQOL and a CLVQOL at the end of the 3 mo follow-up period, and were completed using face-to-face interviews or phone interviews conducted by trained investigators. The minimal clinically important difference(MCID) was calculated using an anchor-based method and a distribution method. In addition, the responsiveness of the questionnaire was measured.RESULTS: A total of 155 residents were enrolled. The average visual acuity(VA) preoperatively was 0.08(SD=0.05), and it increased to 0.47(SD=0.28) at the end of followup. Statistically significant positive changes in the CLVQOL scores indicated significant improvement of vision related quality of life after cataract surgery. With the larger value between the two results as the final value, the MCID values of the CLVQOL(scores of the four scales as well as the total score) were 8.94, 2.61, 4.34, 3.10 and 17.63, respectively. The CLVQOL has both good internal and external responsiveness.CONCLUSION: CLVQOL scores are appropriate instruments for obtaining clinically important changes after cataract surgery. This study is an effective exploration for establishingcataract surgery efficacy standards, which helps clinical and scientific research workers in ophthalmology to gain a more in-depth understanding when using CLVQOL. 展开更多
关键词 responsiveness MINIMAL clinically important DIFFERENCE CHINESE Version of the Low VISION Quality of Life QUESTIONNAIRE CHINESE
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Assessing the Accuracy of the Modified Chinese Autism Spectrum Rating Scale and Social Responsiveness Scale for Screening Autism Spectrum Disorder in Chinese Children 被引量:5
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作者 Bingrui Zhou Hao Zhou +6 位作者 Lijie Wu Xiaobing Zou Xuerong Luo Eric Fombonne Yi Wang Weili Yan Xiu Xu 《Neuroscience Bulletin》 SCIE CAS CSCD 2017年第2期168-174,共7页
The reported prevalence of autism spectrum disorder(ASD) has been increasing rapidly in many parts of the world. However, data on its prevalence in China are largely missing. Here, we assessed the suitability of the... The reported prevalence of autism spectrum disorder(ASD) has been increasing rapidly in many parts of the world. However, data on its prevalence in China are largely missing. Here, we assessed the suitability of the modi?ed Chinese version of a newly-developed ASD screening tool, the Modi?ed Chinese Autism Spectrum Rating Scales(MC-ASRS) in screening for ASD in Chi nese children aged 6–12 years, through comparison with the Social Responsiveness Scale(SRS) that has been widely used for ASD screening. We recruited the par ents/caregivers of 1588 typically-developing children and190 children with ASD aged 6–12 years to complete the MC-ASRS and SRS, and evaluated the validity of both scales in discriminating children with ASD from those developing typically. The results showed that MC-ASRSperformed as well as SRS in sensitivity, speci?city, and area-under-the-curve(both [0.95) in receiver operating characteristic analysis, with a fair false-negative rate.These results suggest that MC-ASRS is a promising tool for screening for children with ASD in the general Chinese population. 展开更多
关键词 Autism spectrum disorder Screening accuracy ROC analysis Modi?ed Chinese Autism Spectrum Rating Scale Social responsiveness Scale
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Passive leg raising as an indicator of fluid responsiveness in patients with severe sepsis 被引量:9
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作者 Zhou-zhou Dong Qiang Fang +1 位作者 Xia Zheng Heng Shi 《World Journal of Emergency Medicine》 CAS 2012年第3期191-196,共6页
In the management of critically ill patients, the assessment of volume responsiveness and the decision to administer a fluid bolus constitute a common dilemma for physicians. Static indices of cardiac preload are poor... In the management of critically ill patients, the assessment of volume responsiveness and the decision to administer a fluid bolus constitute a common dilemma for physicians. Static indices of cardiac preload are poor predictors of volume responsiveness. Passive leg raising (PLR) mimics an endogenous volume expansion (VE) that can be used to predict fluid responsiveness. This study was to assess the changes in stroke volume index (SVI) induced by PLR as an indicator of fluid responsiveness in mechanically ventilated patients with severe sepsis. This was a prospective study. Thirty-two mechanically ventilated patients with severe sepsis were admitted for VE in ICU of the First Affiliated Hospital, Zhejiang University School of Medicine and Ningbo Medical Treatment Center Lihuili Hospital from May 2010 to December 2011. Patients with non-sinus rhythm or arrhythmia, parturients, and amputation of the lower limbs were excluded. Measurements of SVI were obtained in a semi-recumbent position (baseline) and during PLR by the technique of pulse indicator continuous cardiac output (PiCCO) system prior to VE. Measurements were repeated after VE (500 mL 6% hydroxyethyl starch infusion within 30 minutes) to classify patients as either volume responders or non-responders based on their changes in stroke volume index (ASVI) over 15%. Heart rate (HR), systolic artery blood pressure (ABPs), diastolic artery blood pressure (ABPd), mean arterial blood pressure (ABPm), mean central venous pressure (CVPm) and cardiac index (CI) were compared between the two groups. The changes ofABPs, ABPm, CVPm, and SVI after PLR and VE were compared with the indices at the baseline. The ROC curve was drawn to evaluate the value of ASVI and the change of CVPm (ACVPm) in predicting volume responsiveness. SPSS 17.0 software was used for statistical analysis. Among the 32 patients, 22 were responders and 10 were non-responders. After PLR among the responders, some hemodynamic variables (including ABPs, ABPd, ABPm and CVPm) were significantly elevated (101.2±17.6 vs. 118.6±23.7, P=0.03; 52.8±10.7 vs. 64.8±10.7, P=0.006; 68.3±11.7 vs. 81.9±14.4, P=0.008; 6.8±3.2 vs. 11.9±4.0, P=0.001). After PLR, the area under curve (AUC) and the ROC curve of ASVI and ACVPm for predicting the responsiveness after VE were 0.882±0.061 (95%CI 0.759-1.000) and 0.805±0.079 (95%CI 0.650-0.959) when the cut-off levels of ASVI and ACVPm were 8.8% and 12.7%, the sensitivities were 72.7% and 72.7%, and the specificities were 80% and 80%. Changes in ASVI and ACVPm induced by PLR are accurate indices for predicting fluid responsiveness in mechanically ventilated patients with severe sepsis. 展开更多
关键词 Passive leg raising Volume resuscitation Hemodynamic monitoring Stroke volume index Central venous pressure Severe sepsis Fluid responsiveness ROC curve
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Mandatory criteria for the application of variability-based parameters of fluid responsiveness: a prospective study in different groups of ICU patients 被引量:1
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作者 Wolfgang HUBER Uli MAYR +4 位作者 ANDreas UMGELTER Michael FRANZEN Wolfgang REINDL RolAND M.SCHMID Florian ECKEL 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2018年第7期515-524,共10页
Background and objective: Stroke volume variation(SVV) has high sensitivity and specificity in predicting fluid responsiveness. However, sinus rhythm(SR) and controlled mechanical ventilation(CV) are mandatory ... Background and objective: Stroke volume variation(SVV) has high sensitivity and specificity in predicting fluid responsiveness. However, sinus rhythm(SR) and controlled mechanical ventilation(CV) are mandatory for their application. Several studies suggest a limited applicability of SVV in intensive care unit(ICU) patients. We hypothesized that the applicability of SVV might be different over time and within certain subgroups of ICU patients. Therefore, we analysed the prevalence of SR and CV in ICU patients during the first 24 h of Pi CCO-monitoring(primary endpoint) and during the total ICU stay. We also investigated the applicability of SVV in the subgroups of patients with sepsis, cirrhosis, and acute pancreatitis. Methods: The prevalence of SR and CV was documented immediately before 1241 thermodilution measurements in 88 patients. Results: In all measurements, SVV was applicable in about 24%. However, the applicability of SVV was time-dependent: the prevalence of both SR and CV was higher during the first 24 h compared to measurements thereafter(36.1% vs. 21.9%; P0.001). Within different subgroups, the applicability during the first 24 h of monitoring ranged between 0% in acute pancreatitis, 25.5% in liver failure, and 48.9% in patients without pancreatitis, liver failure, pneumonia or sepsis. Conclusions: The applicability of SVV in a predominantly medical ICU is only about 25%–35%. The prevalence of both mandatory criteria decreases over time during the ICU stay. Furthermore, the applicability is particularly low in patients with acute pancreatitis and liver failure. 展开更多
关键词 Hemodynamic monitoring PRELOAD Fluid responsiveness Stroke volume variation Pulse pressure variation
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Azulenoisoindigo: A building block for π-functional materials with reversible redox behavior and proton responsiveness 被引量:1
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作者 Bin Hou Jing Li +4 位作者 Xiaodi Yang Jianwei Zhang Hanshen Xin Congwu Ge Xike Gao 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第4期2147-2150,共4页
Azulene, one of representative nonbenzenoid aromatic hydrocarbons, exhibits unique molecular structure and distinctive physical and chemical properties. Herein, azulenoisoindigo(Az II), an azulene-based isoindigo anal... Azulene, one of representative nonbenzenoid aromatic hydrocarbons, exhibits unique molecular structure and distinctive physical and chemical properties. Herein, azulenoisoindigo(Az II), an azulene-based isoindigo analogue, is designed and synthesized, which has a twisted molecular backbone and R/Sisomers in single crystals. Interestingly, Az II shows the characteristics of both isoindigo and azulene,such as reversible redox behavior and reversible proton responsiveness. UV-vis-NIR,^(1)H NMR and electron paramagnetic resonance(EPR) measurements were carried out to get insights into the possible mechanism of the proton-responsive property of Az II. The results demonstrated that only one azulenyl moiety of molecule of Az II was protonated and deprotonated, and the protonated Az II can be further oxidized to form azulenium cation radicals. 展开更多
关键词 AZULENE Nonbenzenoid aromatic hydrocarbons Isoindigo π-Functional materials Proton responsiveness
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Molecular characterization and developmental expression patterns of thyroid hormone receptors(TRs) and their responsiveness to TR agonist and antagonist in Rana nigromaculata 被引量:4
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作者 Qinqin Lou Yinfeng Zhang +4 位作者 Dongkai Ren Haiming Xu Yaxian Zhao Zhanfen Qin Wuji Wei 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第10期2084-2094,共11页
Considering some advantages of Rana nigromaculata as an experimental species, we propose that this species, like Xenopus laevis, could be used to assay thyroid hormone(TH) signaling disrupting actions. To validate t... Considering some advantages of Rana nigromaculata as an experimental species, we propose that this species, like Xenopus laevis, could be used to assay thyroid hormone(TH) signaling disrupting actions. To validate the utilizability of R. nigromaculata, we investigated the responsiveness of R. nigromaculata to a TH receptor(TR) agonist(T3) and antagonist(amiodarone) by analyzing expression, based on characterizing TR cDNA and developmental expression patterns. With high levels of identity with the corresponding genes in X. laevis, both TRα and TRβ in R. nigromaculata exhibited roughly similar developmental expression patterns to those of X. laevis, in spite of some species-specific differences. Both TRα and TRβ expression had greater changes in the liver and intestine than in the tail and brain during metamorphosis. T3 exposure for 2 days induced more dramatic increases of TRβ expression in stage 27 than in stage34 tadpoles but not in stage 42 tadpoles, showing that the responsiveness of R. nigromaculata to TH decreased with development and disappeared at the onset of metamorphic climax.Corresponding to greater changes of TRβ expression in the liver and intestine than in the tail and brain during metamorphosis, the liver and intestine had higher responsiveness to exogenous T3 than the tail and brain. Amiodarone inhibited T3-induced TRβ expression. Our results show that R. nigromaculata can be used as a model species for assaying TH signaling disrupting actions by analyzing TRβ expression, and intestine tissues at stage 27 are ideal test materials due to high responsiveness and easy accessibility. 展开更多
关键词 Rana nigromaculata Thyroid hormone receptor Thyroid hormone signaling Developmental expression pattern responsiveness
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Arterial Pulse Pressure Variation versus Central Venous Pressure as a Predictor for Fluid Responsiveness during Open Major Abdominal Operations 被引量:2
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作者 Mostafa M. Hussein Raham H. Mostafa 《Open Journal of Anesthesiology》 2018年第2期43-53,共11页
Introduction: Fluid resuscitation is the cornerstone in the management of hemodynamically unstable patients. Dynamic parameters of fluid responsiveness, like pulse pressure variation, have the advantage of being more ... Introduction: Fluid resuscitation is the cornerstone in the management of hemodynamically unstable patients. Dynamic parameters of fluid responsiveness, like pulse pressure variation, have the advantage of being more reliable index for fluid management. Objective: The aim of our study was to compare between arterial pulse pressure variation (PPV) versus central venous pressure (CVP) as a predictor for fluid responsiveness during major open abdominal operations. Patients and Methods: 60 adult patients under general anesthesia with mechanical ventilation underwent open major abdominal surgical procedures were included in our prospective randomized controlled study. Intravenous fluid was infused and monitored by CVP in control group or by PPV in the other group. Hemodynamic variables (heart rate, invasive blood pressure, PPV and CVP) were measured at baseline after anesthesia induction and every 10 min, during first hour of operation, and then every 15 min, till end of surgery. Blood loss and total i.v. fluid & blood transfusion given to patients were recorded and compared between two groups intraoperatively. Results: Patients in the PPV group required more intraoperative fluid and blood transfusion than patients in CVP group to achieve more stable hemodynamic parameters. The fall in blood pressure (>20% of baseline) and increase in heart rate are more common in CVP group (p Conclusion: PPV is a better predictor and a good guide for fluid responsiveness. More stable hemodynamic variables are observed in PPV group. 展开更多
关键词 Central VENOUS PRESSURE Pulse PRESSURE Variation Fluid responsiveness
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Meta-Analysis of Ventilated versus Spontaneously Breathing Patients in Predicting Fluid Responsiveness by Inferior Vena Cava Variation 被引量:1
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作者 Xiang Si Daiyin Cao +1 位作者 Hailin Xu Xiangdong Guan 《International Journal of Clinical Medicine》 2018年第10期760-777,共18页
Purpose: Respiratory variation in inferior vena cava (&Delta;IVC) has been extensively studied in predicting fluid responsiveness, but the results are conflicting. We performed a systemic review and meta-analysis ... Purpose: Respiratory variation in inferior vena cava (&Delta;IVC) has been extensively studied in predicting fluid responsiveness, but the results are conflicting. We performed a systemic review and meta-analysis of studies aiming at investigating the diagnostic accuracy of &Delta;IVC in predicting fluid responsiveness. Methods: MEDLINE, EMBASE, Cochrane Database and Web of Science were screened for relevant original and review articles from inception to July 2016. The meta-analysis determined the pooled sensitivity, specificity, diagnostic odds ratio (DOR) and area under the ROC curve (AUROC). In addition, subgroup analyses were performed in mechanically ventilated patients and spontaneously breathing patients. Results: A total of 20 studies involving 635 patients were included. Cutoff values of &Delta;IVC varied from 12% to 42%, the pooled sensitivity and specificity was 0.68 (0.62 - 0.75) and 0.80 (0.75 - 0.85), respectively. The DOR was 14.2 (6.0 - 33.6) and the AUROC was 0.86 (0.78 - 0.93). Subgroup analysis showed better diagnostic performance in patients on mechanical ventilation than in spontaneously breathing patients with higher sensitivity (0.75 vs. 0.56), specificity (0.82 vs. 0.78), DOR (22.9 vs. 7.9) and AUROC (0.90 vs. 0.80). The best threshold of &Delta;IVC in patients on mechanical ventilation was IVC distensibility index (&Delta;IVC &ge;17% &plusmn;4%), compared to IVC collapsibility index (&Delta;cIVC &ge;33% &plusmn;12%) in spontaneously breathing patients. Conclusion: &Delta;IVC is not an accurate predictor of fluid responsiveness in patients with acute circulatory failure. In patients on mechanical ventilation, the predicting ability of &Delta;IVC was moderate with acceptable sensitivity and specificity;in spontaneously breathing patients, the specificity remains acceptable but its sensitivity is poor. 展开更多
关键词 Fluid responsiveness INFERIOR Vena Cava VARIATION
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Remodeled structure and reduced contractile responsiveness of ocular ciliary artery in spontaneously hypertensive rats
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作者 Ya-Ru Dong Claire E Gustafson +2 位作者 Jun Wang Ji-Zhe Cui Takeshi Yoshitomi 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第3期363-368,共6页
AIM: To investigate the alterations in both structure and contractile responsiveness of ocular ciliary artery(OCA) in spontaneously hypertensive rat(SHR).METHODS: In this experiment, 20-week-old male SHR and Wistar Ky... AIM: To investigate the alterations in both structure and contractile responsiveness of ocular ciliary artery(OCA) in spontaneously hypertensive rat(SHR).METHODS: In this experiment, 20-week-old male SHR and Wistar Kyoto rat(WKY) were studied. The heart rate(HR), the blood pressure(BP; the systolic BP and the diastolic BP) of rats with an electronic sphygmomanometer were measured. Vascular morphometry and isometric tension measurement were used to investigate the alterations in structure and contractility of OCA.RESULTS: A general narrowing of OCAs was observed in SHR compared to the control WYK. In SHR, the media of OCAs were thicker, the luminal diameters were smaller, and the media-to-lumen ratios were higher when compared with WKY(P<0.05). The contractions of OCAs evoked by norepinephrine were smaller in SHR compared to control(P<0.05). Then, OCAs were pretreated with iberiotoxin, L-NAME, or indomethacin 30 min before norepinephrineinduced contraction. Iberiotoxin(0.1 μmol/L) has not changed the norepinephrine-induced contractions in OCAs from both groups. However, L-NAME(100 μmol/L) increased the vasoconstrictions, the increased extents were similar in SHR and WKY(P>0.05). Indomethacin(10 μmol/L) decreased the contractions induced by norepinephrine in OCAs from WKY(P<0.05), but did not change those contractions in vessels from SHR(P>0.05).CONCLUSION: Our results demonstrate that the structure and function of OCAs are altered in hypertension. OCAs from SHR are remodeled with decreased lumen diameter and increased media-to-lumen ratio. Moreover, the contractile responsiveness of OCAs from SHR is diminished due to the disruption of vasoconstrictive effect of prostaglandins. 展开更多
关键词 remodeled STRUCTURE CONTRACTILE responsiveness OCULAR CILIARY ARTERY hypertension spontaneously hypertensive rat
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Molecular Characterization of Thyroid Hormone Receptors (TRs) and their Responsiveness to T3 in Microhylafissipes
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作者 Lusha LIU Xungang WANG +1 位作者 Mengjie ZHANG Jianping JIANG 《Asian Herpetological Research》 SCIE CSCD 2018年第1期13-23,共11页
To explore and enrich the molecular mechanisms of thyroid hormone receptors (TRs) in the metamorphosis of amphibians, the cDNA sequences of TRa and TRβ in Microhyla fissipes were cloned and characterized. TRa was 1... To explore and enrich the molecular mechanisms of thyroid hormone receptors (TRs) in the metamorphosis of amphibians, the cDNA sequences of TRa and TRβ in Microhyla fissipes were cloned and characterized. TRa was 1 706 bp in length with an open reading frame (ORF) of 1 257 bp encoding a predicted protein of 418 amino acids and TRβ was 1 422 bp with an ORF of 1 122 bp encoding a predicted protein of 373 amino acids. Their protein sequences contained 4 conserved domains of the nuclear receptor superfamily with two highly conserved cysteine-rich zinc fingers in the DNA-binding domain, whereas TRβ was 42 amino acids shorter in its A/B domain than TRot. Highly-conserved sequences and structures indicated their conserved functions during metamorphosis. TRa expression reached peak at 12 h and then decreased from 12 h to 48 h. While dramatically up-regulated TRβ was observed after exposure of T3 within 24 h, and it was down-regulated from 24 h to 48 h. The expression pattern of TRβ is similar to that in the natural metamorphosis. Furthermore, tadpoles treated 24 h also resembled the climax of metamorphosis tadpoles and TRβ expression had higher responsiveness than TRa to T3 in M. fissipes. These results suggest M. fissipes may serve as the model to assay environmental compounds on TH signaling disruption. 展开更多
关键词 Microhylafissipes thyroid hormone receptors functional characteristic expression pattern responsiveness
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Individual Differences in Stress Responsiveness of the Hypothalamic-Pituitary-Adrenal Axis and Its Vasopressinergic Regulation in Old Monkeys
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作者 Nadezhda D. Goncharova Victor Yu. Marenin Tamara E. Oganyan 《Journal of Behavioral and Brain Science》 2015年第7期280-294,共15页
Stress adaptation is fundamental for health, and the hypothalamic-pituitary-adrenal axis (HPA) is one of its main mechanisms. Considerable data indicate that arginine vasopressin (AVP) related disturbances of stress a... Stress adaptation is fundamental for health, and the hypothalamic-pituitary-adrenal axis (HPA) is one of its main mechanisms. Considerable data indicate that arginine vasopressin (AVP) related disturbances of stress adaptation can occur with aging. However, most studies of such kind have been performed on rodents, give contradictory results and fail to consider individual characteristics of the animals. The purpose of this study was to investigate individual HPA responsiveness to acute stress and its vasopressinergic regulation in old female rhesus monkeys that differ in their behavioral responses to stress. Animals with depression-like or anxiety-like behavior (DAB) responded with higher plasma levels of ACTH and AVP, lower levels of corticosteroids and higher cortisol/DHEAS molar ratios to restraint stress and to insulin-induced hypoglycemia compared with animals with healthy adaptive behavior. AVP and ACTH dynamics were closely correlated in most animals. AVP treatment produced differences in HPA responses similar to those produced by the stressors. The ACTH response to hypoglycemic stress in the DAB animal with highest HPA responsiveness was dramatically reduced by prior administration of a V1b receptor antagonist. These results suggest that the dysfunctions of HPA observed in old animals with DAB are caused by increased tone of the vasopressinergic system in regulation of HPA stress reactivity. 展开更多
关键词 Hypothalamic-Pituitary-Adrenal Axis STRESS responsiveness Vasopressinergic REGULATION Different Types of Adaptive Behavior Aging
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MONTE CARLO SIMULATION FOR MODELING THE EFFECT OF GROUND SEGMENT LOCATION ON IN-ORBIT RESPONSIVENESS OF LEO SUNSYNCHRONOUS SATELLITES
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作者 M.Navabi Hossein Bonyan Khamseh 《Journal of Electronics(China)》 2011年第2期239-248,共10页
Responsiveness is a challenge for space systems to sustain competitive advantage over al-ternate non-spaceborne technologies.For a satellite in its operational orbit,in-orbit responsiveness is defined as the capabilit... Responsiveness is a challenge for space systems to sustain competitive advantage over al-ternate non-spaceborne technologies.For a satellite in its operational orbit,in-orbit responsiveness is defined as the capability of the satellite to respond to a given demand in a timely manner.In this paper,it is shown that Average Wait Time(AWT) to pick up user demand from ground segment is the ap-propriate metric to evaluate the effect of ground segment location on in-orbit responsiveness of Low Earth Orbit(LEO) sunsynchronous satellites.This metric depends on pattern of ground segment access to satellite and distribution of user demands in time domain.A mathematical model is presented to determine pattern of ground segment access to satellite and concept of cumulative distribution function is used to simulate distribution of user demands for markets with different total demand scenarios.Monte Carlo simulations are employed to take account of uncertainty in distribution and total volume of user demands.Sampling error and standard deviation are used to ensure validity of AWT metric obtained from Monte Carlo simulations.Incorporation of the proposed metric in the ground segment site location process results in more responsive satellite systems which,in turn,lead to greater customer satisfaction levels and attractiveness of spaceborne systems for different applications.Finally,simula-tion results for a case study are presented. 展开更多
关键词 Ground segment location In-orbit responsiveness Sunsynchronous satellite
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Hypersensitivity of vascular alpha-adrenoceptor responsiveness: a possible inducer of pain in neuropathic states
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作者 Robert W.Teasell Qingping Feng 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第1期165-165,共1页
Dear editor,Dr. Peter Drummond's article noted that peripheral nerve and tissue injury in neuropathic pain syndromes releases cytokines which in turn lead to an increase in alphal-adrenoceptor upreg- ulation, resulti... Dear editor,Dr. Peter Drummond's article noted that peripheral nerve and tissue injury in neuropathic pain syndromes releases cytokines which in turn lead to an increase in alphal-adrenoceptor upreg- ulation, resulting in a heightened sensitivity to noradrenaline. In these circumstances, noradrenaline acting on upregulated alpha1 a-adrenoceptors increases the release of cytokine interleukin-6. Hence, nociceptive afferent neurons exposed to injury induced cytokines become more hypersensitive to noradrenaline, which in turn promotes the release of more inflammatory cytokines. Dr. Drummond noted that this mechanism may contribute to the pain of post-herpetic neuralgia or complex regional pain syn- drome (Drummond, 2014). 展开更多
关键词 Hypersensitivity of vascular alpha-adrenoceptor responsiveness a possible inducer of pain in neuropathic states
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Dynamic-Distributed Load Balancing for Highly-Performance and Responsiveness Distributed-GIS (D-GIS)
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作者 Aissatou Diasse Foroski Kone 《Journal of Geographic Information System》 2011年第2期128-139,共12页
In recent years, several results have been introduced to enhance distributed GIS performance. While much more efforts have focused on tile map and simple symbologies on dynamic map, load balancing GIS servers have not... In recent years, several results have been introduced to enhance distributed GIS performance. While much more efforts have focused on tile map and simple symbologies on dynamic map, load balancing GIS servers have not been addressed by the GIS community so far. This paper, therefore, proposed dynamic distributed load balancing for D-GIS in order to quickly render information to client interface by involving a set of GIS servers which process clients’ requests depending of an algorithm. In the model, several concepts were introduced and defined: Virtual Server within physical machine which constitutes a setup environment for a single GIS server, Load Hash Table which contains information about virtual server’s capacity, real-time load and other mandatory elements, Request Split Table which splits requests depending of the input area’s Quantity of Information and stores request tasks composition for later reconstitution. At last we have Distributed Failover Callback Function Table level one (respectively level two) which determines whether or not the request had been successfully processed by the chosen virtual server (respectively physical machine). This table allows sending back the same request to another virtual server (respectively physical node). Two load handlers (primary and secondary) are defined in case of failure. Our Model achieves efficient load balancing by: providing efficient node selection;optimizing request routing;managing node failover;involving client’s request partitioning and introducing method type decomposition. A simulation of the algorithm shows a low response time when performing GIS operations. 展开更多
关键词 LOAD Balancing Distributed-GIS PERFORMANCE responsiveness
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