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A Tutorial on Common Differential Equations and Solutions Useful for Modeling Epidemics Like COVID-19: Linear and Non-Linear Compartmentation Models
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作者 Robert V. Mulkern Reyhaneh Nosrati 《Journal of Applied Mathematics and Physics》 2022年第10期3053-3071,共19页
Purpose: To review some of the basic models, differential equations and solutions, both analytic and numerical, which produce time courses for the fractions of Susceptible (S), Infectious (I) and Recovered (R) fractio... Purpose: To review some of the basic models, differential equations and solutions, both analytic and numerical, which produce time courses for the fractions of Susceptible (S), Infectious (I) and Recovered (R) fractions of the population during the epidemic and/or endemic conditions. Methods: Two and three-compartment models with analytic solutions to the proposed linear differential equations as well as models based on the non-linear differential equations first proposed by Kermack and McKendrick (KM) [1] a century ago are considered. The equations reviewed include the ability to slide between so-called Susceptible-Infected-Recovered (SIR), Susceptible-Infectious-Susceptible (SIS), Susceptible-Infectious (SI) and Susceptible-Infectious-Recovered-Susceptible (SIRS) models, effectively moving from epidemic to endemic characterizations of infectious disease. Results: Both the linear and KM model yield typical “curves” of the infected fraction being sought “to flatten” with the effects of social distancing/masking efforts and/or pharmaceutical interventions. Demonstrative applications of the solutions to fit real COVID-19 data, including linear and KM SIR fit data from the first 100 days following “lockdown” in the authors’ locale and to the total number of cases in the USA over the course of 1 year with SI and SIS models are provided. Conclusions: COVID-19 took us all by surprise, all wondering how to help. Spreading a basic understanding of some of the mathematics used by epidemiologists to model infectious diseases seemed like a good place to start and served as the primary purpose for this tutorial. 展开更多
关键词 COVID-19 Differential Equations Modelling Compartment Model
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Prone position ventilation in severe acute pancreatitis patients with concurrent acute respiratory distress syndrome and abdominal compartment syndrome:a case report
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作者 Jiaping Yu Yun Ji Haifei Lu 《World Journal of Emergency Medicine》 2026年第1期98-100,共3页
Severe acute pancreatitis(SAP)can induce acute respiratory distress syndrome(ARDS)and abdominal compartment syndrome(ACS).Although prone position ventilation(PPV)can improve outcomes in patients with ARDS,there is sig... Severe acute pancreatitis(SAP)can induce acute respiratory distress syndrome(ARDS)and abdominal compartment syndrome(ACS).Although prone position ventilation(PPV)can improve outcomes in patients with ARDS,there is significant controversy regarding its concurrent use with ACS owing to concerns of increased risk of intra-abdominal pressure(IAP).[1]We present a case of successful PPV application without adverse eff ects. 展开更多
关键词 severe acute pancreatitis sap can prone position ventilation ppv can acute respiratory distress syndrome abdominal compartment syndrome abdominal compartment syndrome acs prone position ventilation intra abdominal pressure acute respiratory distress syndrome ards
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Specific dendritic spine modifications and dendritic transport:From in vitro to in vivo
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作者 Albert H.K.Fok Charlotte H.M.Lam Cora S.W.Lai 《Neural Regeneration Research》 2026年第2期665-666,共2页
Dendritic spines are small protrusions along dendrites that contain most of the excitatory synapses in principal neurons,playing a crucial role in neuronal function by creating a compartmentalized environment for sign... Dendritic spines are small protrusions along dendrites that contain most of the excitatory synapses in principal neurons,playing a crucial role in neuronal function by creating a compartmentalized environment for signal transduction.The plasticity of spine morphologies provides a tunable handle to regulate calcium signal dynamics,allowing rapid regulation of protein expression necessary to establish and maintain synapses(Cornejo et al.,2022).If excitatory inputs were to be located primarily on dendritic shafts,dendrites would frequently short-circuit,preventing voltage signals from propagating(Cornejo et al.,2022).It is thus not surprising that the structural plasticity of dendritic spines is closely linked to synaptic plasticity and memory formation(Berry and Nedivi,2017).While comprehensive in vitro studies have been conducted,in vivo studies that directly tackle the mechanism of dendritic transport and translation in regulating spine plasticity spatiotemporally are limited. 展开更多
关键词 excitatory synapses principal neuronsplaying compartmentalized environment establish maintain synapses cornejo dendritic spines regulate calcium signal dynamicsallowing regulation protein expression dendritic shaft
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Flow field distribution and overpressure characteristics inside the crew compartment of a truck-mounted howitzer under the effect of muzzle blast 被引量:1
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作者 Shengcheng Wei Linfang Qian +2 位作者 Yadong Xu Qiang Yin Xinyu Xiong 《Defence Technology(防务技术)》 2025年第2期190-205,共16页
The muzzle blast overpressure induces disturbances in the flow field inside the crew compartment(FFICC)of a truck-mounted howitzer during the artillery firing.This overpressure is the primary factor preventing personn... The muzzle blast overpressure induces disturbances in the flow field inside the crew compartment(FFICC)of a truck-mounted howitzer during the artillery firing.This overpressure is the primary factor preventing personnel from firing artillery within the cab.To investigate the overpressure characteristics of the FFICC,a foreign trade equipment model was used as the research object,and a numerical model was established to analyze the propagation of muzzle blast from the muzzle to the interior of the crew compartment under extreme firing condition.For comparative verification,the muzzle blast experiment included overpressure data from both the flow field outside the crew compartment(FFOCC)and the FFICC,as well as the acceleration data of the crew compartment structure(Str-CC).The research findings demonstrate that the overpressure-time curves of the FFICC exhibit multi-peak characteristics,while the pressure wave shows no significant discontinuity.The enclosed nature of the cab hinders the dissipation of pressure wave energy within the FFICC,leading to sustained high-amplitude overpressure.The frameskin structure helps attenuate the impact of muzzle blast on the FFICC.Conversely,local high overpressure caused by the convex or concave features of the cab's exterior significantly amplifies the overpressure amplitude within the FFICC. 展开更多
关键词 Truck-mounted howitzer Muzzle blast Flow field inside the crew compartment(FFICC) Overpressure characteristics Flow-structure interaction
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Atraumatic acute compartment syndrome secondary to prolonged intoxication induced recumbency:a case series
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作者 Jacob Greenspan Ariella Gartenberg +1 位作者 Claudia Sofia Simich Michael Halperin 《World Journal of Emergency Medicine》 2025年第6期593-596,共4页
Acute compartment syndrome(ACoS)involves a complex pathological process in which rising pressures within an enclosed muscle space ultimately result in anoxia and cell death.The most common etiologies include long bone... Acute compartment syndrome(ACoS)involves a complex pathological process in which rising pressures within an enclosed muscle space ultimately result in anoxia and cell death.The most common etiologies include long bone fractures,crush injuries,and burns.[1,2]While rare,ACoS can also occur in atraumatic settings following periods of prolonged limb compression,such as intoxication.[3]Atraumatic ACoS is easily overlooked,resulting in diagnostic delay and poor patient outcomes.Prompt recognition and surgical management is essential to prevent critical sequelae. 展开更多
关键词 recumbency acute compartment syndrome acos involves recognition surgical manag rising pressures ATRAUMATIC acute compartment syndrome INTOXICATION diagnostic delay
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Rice OsMYB9 enhances salt stress tolerance by regulating the vacuolar Na^(+)/H^(+)antiporter
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作者 Boyeong Kim Sung-Hwan Cho +3 位作者 Yejin Shim Hyeryung Yoon Nam-Chon Paek Kiyoon Kang 《The Crop Journal》 2025年第6期1718-1730,共13页
Salinity is a major hazard to crop plant growth and significantly reduces grain yield.When subjected to high salinity,plants maintain ion homeostasis through Na^(+)compartmentalization and exclusion,enabling them to m... Salinity is a major hazard to crop plant growth and significantly reduces grain yield.When subjected to high salinity,plants maintain ion homeostasis through Na^(+)compartmentalization and exclusion,enabling them to mitigate salt stress.In this study,we revealed the role of rice(Oryza sativa)MYB9(OsMYB9)in regulating salt stress tolerance.OsMYB9 was expressed in the vascular bundles of roots and leaves,particularly in the parenchyma cells.The null mutation of OsMYB9 resulted in increased sodium ion accumulation in shoot tissues under salt stress,leading to salt-sensitive phenotypes.Real-Time Quantitative Reverse Transcription PCR analysis indicated the OsMYB9 mutation led to decreased expression of several genes associated with vacuolar Na^(+)/H^(+)antiporters(OsNHX1,OsNHX2,OsNHX3,OsNHX4,and OsNHX5),high-K^(+)affinity transporters(OsHKT1;5),and SALT OVERLY SENSITIVE proteins(OsSOS2 and OsSOS3).Among these,OsMYB9 upregulated the expression of OsNHX1 and OsNHX2 by directly binding to their promoter regions.Furthermore,GIGANTEA(OsGI)interacted with OsMYB9,suggesting that OsGI negatively acts upstream of OsMYB9 and regulates the expression levels of OsNHX1.Collectively,OsMYB9 alleviates the excess accumulation of Na^(+)ions in the xylem by retrieving Na^(+)ions from xylem parenchyma cells and compartmentalizing them into vacuoles.These regulatory mechanisms mediated by OsMYB9 are crucial for minimizing Na^(+)toxicity in photosynthetic tissues and enhancing salt stress tolerance in rice. 展开更多
关键词 RICE Salt stress tolerance OsMYB9 COMPARTMENTALIZATION Sodium ion
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Abdominal compartment syndrome with colonic hypoganglionosis and massive colonic distension in a young adult:A case report
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作者 Eric Bergeron Adrian Gologan 《World Journal of Clinical Cases》 2025年第33期89-97,共9页
BACKGROUND Hypoganglionosis is a rare gastrointestinal acquired motility disorder that res-embles Hirschsprung’s disease and can manifest in the adult life.Abdominal compartment syndrome,a condition characterized by ... BACKGROUND Hypoganglionosis is a rare gastrointestinal acquired motility disorder that res-embles Hirschsprung’s disease and can manifest in the adult life.Abdominal compartment syndrome,a condition characterized by an increase in intra-abdo-minal pressure with physiological disturbance can be caused by severe massive fecal impaction.CASE SUMMARY A 33-year-old female presented to the emergency room with massive abdominal distension that rapidly progressed to abdominal compartment syndrome.The pa-tient was diagnosed with hypoganglionosis.Life-saving emergent proctoco-lectomy was performed to save the patient.CONCLUSION Abdominal compartment syndrome can develop secondary to excessive colonic distension.This extreme but rare situation must be addressed immediately.Hypo-ganglionosis is a potential cause of severe constipation that may present in adu-lthood. 展开更多
关键词 Abdominal compartment syndrome HYPOGANGLIONOSIS Hirchprung’s disease Constipation PROCTOCOLECTOMY Case report
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Towards comprehensive care in crush syndrome:Expanding the multidisciplinary framework
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作者 Luca Galassi Federica Facchinetti 《World Journal of Orthopedics》 2025年第9期76-79,共4页
Crush syndrome demands an integrated multidisciplinary approach that spans acute surgical decisions and long-term functional recovery.In response to Khan et al’s recent systematic review,we propose complementary pers... Crush syndrome demands an integrated multidisciplinary approach that spans acute surgical decisions and long-term functional recovery.In response to Khan et al’s recent systematic review,we propose complementary perspectives that address two underrepresented dimensions:Vascular surgical decision-making and psychiatric rehabilitation.We emphasize the use of intraoperative technologies such as indocyanine green fluorescence angiography and compartment pressure monitoring to guide limb salvage strategies and reperfusion management.Additionally,we advocate for the systematic integration of mental health screening and trauma-informed psychiatric care to address the high prevalence of psychological distress in survivors.Embedding these domains into standardized protocols could enhance both short-and long-term outcomes,particularly in highimpact trauma and disaster settings. 展开更多
关键词 Crush syndrome Compartment syndrome Reperfusion injury THROMBOEMBOLISM FASCIOTOMY Mental health Multidisciplinary management
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Numerical simulation of flow regions in red mud separation thickener's feedwell by analysis of residence-time distribution 被引量:4
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作者 周天 李茂 +3 位作者 李秋龙 雷波 周谦 周孑民 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1117-1124,共8页
The residence-time distribution (RTD) and the compartment model were applied to characterizing the flow regions in red mud separation thickener’s feedwells. Combined with the experimental work, validated mathematic... The residence-time distribution (RTD) and the compartment model were applied to characterizing the flow regions in red mud separation thickener’s feedwells. Combined with the experimental work, validated mathematical model as well as three-dimensional computational fluid dynamics (CFD) model was established to analyze the flow regions of feedwells on an industrial scale. The concept of RTD, although a well-known method for the characterization of mixing behavior in conventional mixers and reactors, is still a novel measure for the characterization of mixing in feedwells. Numerical simulation results show that the inlet feed rate and the aspect ratio of feedwells are the most critical parameters which affect the RTD of feedwell. Further simulation experiments were then carried out. Under the optimal operation conditions, the volume fraction of dead zone can reduce by10.8% and an increasement of mixing flow volume fraction by 6.5% is also observed. There is an optimum feed inlet rate depending on the feedwell design. The CFD model in conjunction with the RTD analysis then can be used as an effective tool in the design, evaluation and optimization of thickener feedwell in the red mud separation. 展开更多
关键词 computational fluid dynamics residence-time distribution compartment model feedwell
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A high performance liquid chromatography method for the quantitative determination of ribavirin in human plasma and its application in a pharmacokinetics study 被引量:2
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作者 张华 王桂玲 +2 位作者 李可欣 张烜 张强 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2013年第4期361-364,共4页
The clinical pharmacokinetics of ribavirin after a single oral dose of 600 mg ribavirin tablets in healthy Chinese volunteers was studied. A rapid and simple high performance liquid chromatography (HPLC) method was ... The clinical pharmacokinetics of ribavirin after a single oral dose of 600 mg ribavirin tablets in healthy Chinese volunteers was studied. A rapid and simple high performance liquid chromatography (HPLC) method was developed to determine the ribavirin concentration in human plasma. C18 column was used for separation with a column temperature of 25℃, the mobile phase was ultrapure water adjusted to pH 3 with acetic acid at the flow rate of 1 mL/min, and the detection wavelength was set at 207 rim. The linear range of the standard curves was 50.4-2016.0 ng/mL and the lower limit of quantification (LLOQ) was 50.4 ng/mL. The relative recoveries of ribavirin were more than 90% in plasma. The RSD of the intra-day precision was less than 10% and that of inter-day was less than 15%. The pharmacokinetic parameters of ribavirin were calculated by WinNonlin. Results indicated that the two-compartment model was a better model for describing the pharmacokinetics profile of ribavirin than one-compartment model. The AUC0-t was 10807.8 h.ng/mL, the CL/F was 64879.5 mL, and the Cmax was 525.1 ng/mL. These results provided the experimental data for the development of ribavirin dosage form. 展开更多
关键词 RIBAVIRIN HPLC PHARMACOKINETICS Compartmental model
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Mechanisms of Enhanced Heavy Metal Tolerance in Plants by Silicon: A Review 被引量:23
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作者 WU Jia-Wen SHI Yu +2 位作者 ZHU Yong-Xing WANG Yi-Chao GONG Hai-Jun 《Pedosphere》 SCIE CAS CSCD 2013年第6期815-825,共11页
In recent years,due to excessive emission of industrial waste,wastewater irrigation,and unreasonable utilization of fertilizers,pesticides and plastic sheeting,heavy metal pollution is increasing rapidly,resulting in ... In recent years,due to excessive emission of industrial waste,wastewater irrigation,and unreasonable utilization of fertilizers,pesticides and plastic sheeting,heavy metal pollution is increasing rapidly,resulting in many environmental problems.Silicon(Si),as the second most abundant element in the soil,can not only stimulate plant growth,but alleviate various biotic and abiotic stresses,including heavy metal stress.Here,we reviewed recent advances in the mechanisms for Si-mediated heavy metal tolerance in plants.These mechanisms included reducing active heavy metal ions in growth media,reducing heavy metal transport to the shoot,stimulating enzymatic and non-enzymatic antioxidants,chelation,compartmentation,regulation of the expression of metal transport genes,and structural changes in plants.Further research orientation is also discussed. 展开更多
关键词 ANTIOXIDANT CADMIUM compartmentation detoxifieation MANGANESE
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Zn Accumulation and Subcellular Distribution in the Zn Hyperaccumulator Sedurn alfredii Hance 被引量:17
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作者 LI Ting-Qiang YANG Xiao-E YANG Jin-Yan HE Zhen-Li 《Pedosphere》 SCIE CAS CSCD 2006年第5期616-623,共8页
Zn accumulation and subcellular distribution in leaves of the hyperaccumulating ecotype (HE) and non-hyperaccumulating ecotype (NHE) of Sedum alfredii Hance were studied using radiotracer and gradient centrifugati... Zn accumulation and subcellular distribution in leaves of the hyperaccumulating ecotype (HE) and non-hyperaccumulating ecotype (NHE) of Sedum alfredii Hance were studied using radiotracer and gradient centrifugation techniques. Leaf Zn accumulation in the HE of S. alfredii was 18.5-26.7 times greater than that in the NHE when the plants were grown at 1-500μmol Zn L-1. Leaf section uptake of 65Zn was highly dependent on external Zn levels. Greater 65Zn uptake in HE was noted only at external Zn levels 〉 100μmol L-1. Zinc subcellular distribution in the leaves of the two ecotypes of S. alfredii was: cell wall 〉 soluble fraction 〉 cell organelle. However, more Zn was distributed to the leaf cell wall and soluble fractions for HE than for NHE. In the leaf of HE, 91%-94% of the Zn was found in the cell walls and the soluble fraction and only 6%-9% Zn was distributed in the cell organelle fraction. For NHE, about 20%-26% Zn was recovered in the cell organelle fraction. In stems, Zn distribution to the ceil wail fraction was approximately two fold greater in the HE than that in the NHE. For the hyperaccumulating ecotype of S. alfredii, the cell wall and the vacuole played a very important role in Zn tolerance and hyperaccumulation. 展开更多
关键词 compartmentation Sedum alfredii Hance subcellular distribution Zn hyperaccumulator
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Glutamine analogs promote cytoophidium assembly in human and Drosophila cells 被引量:14
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作者 mr Yilmaz Tastan Zillah Anne Deussen Mayte Yu-Yin Siswick 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2011年第9期391-402,共12页
CTP synthase is compartmentalized within a subcellular structure,termed the cytoophidium,in a range of organisms including bacteria, yeast,fruit fly and rat.Here we show that CTP synthase is also compartmentalized int... CTP synthase is compartmentalized within a subcellular structure,termed the cytoophidium,in a range of organisms including bacteria, yeast,fruit fly and rat.Here we show that CTP synthase is also compartmentalized into cytoophidia in human cells.Surprisingly,the occurrence of cytoophidia in human cells increases upon treatment with a glutamine analog 6-diazo-5-oxo-L-norleucine(DON),an inhibitor of glutamine-dependent enzymes including CTP synthase.Experiments in flies confirmed that DON globally promotes cytoophidium assembly.Clonal analysis via CTP synthase RNA interference in somatic cells indicates that CTP synthase expression level is critical for the formation of cytoophidia.Moreover,DON facilitates cytoophidium assembly even when CTP synthase level is low.A second glutamine analog azaserine also promotes cytoophidum formation.Our data demonstrate that glutamine analogs serve as useful tools in the study of cytoophidia. 展开更多
关键词 AZASERINE CTP synthase Cytoophidium 6-diazo-5-oxo-L-norleucine DROSOPHILA HeLa cell lntracellular compartmentation
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Discussion on the Problem of Salt Gland of Glycine soja 被引量:6
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作者 周三 赵可夫 《Acta Botanica Sinica》 CSCD 2003年第5期574-580,共7页
Glycine soja Sieb. et Zucc. plants living in saline soil in three provinces of China were treated with different salinity concentrations under different laboratory culture conditions (including solution, sand and fiel... Glycine soja Sieb. et Zucc. plants living in saline soil in three provinces of China were treated with different salinity concentrations under different laboratory culture conditions (including solution, sand and field cultivation). The attachment shape and distribution on the surface of stalk and leaf of G. soja plants were observed with scanning electron microscopy (SEM), and the ultrastructure of glandular hair with transmission electron microscopy (TEM). Na+ and Cl- contents in the secretion of the leaf surface and inside the leaf of G. soja subjected to different treatments were measured. The Na+ relative contents in glandular cells, epidermal cells and mesophyllous cells of leaves under different salinities were determined by X-ray microanalysis. Results show that only glandular and epidermal hair exist on the surface attachments of leaves and stalks of G. soja plants. These glandular hair were similar in shape to some salt glands of Gramineae halophytes, and they attached to the vein on the leaf surface. The cell structure of the glandular hair showed the characteristics of common salt glands, such as big vacuoles, dense cytoplasm, a great deal of mitochondria, chloroplast, plasmodesmata and thicker cell walls, etc. The results of Na+ and Cl- contents in the leaf secretion and inside the leaf showed that the glandular hair executed the function of salt-secretion, and when treated with the salt gland inhibitor the salt-secretion process was inhibited. As a result, Na+ and Cl- were mainly accumulated inside G. soja leaves. The results of Na+ X-ray microanalysis under different salinities proved that the three cells of the glandular hair, especially the top cell, possessed strong competence for Na+ accumulation. Above all, the glandular hair were the salt gland, and no other kind of salt glands were found on G. soja plants. The secreting mechanism of the salt gland was also discussed. 展开更多
关键词 Glycine soja salt gland ULTRASTRUCTURE ion compartmentalization
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Expression of Recombinant Tryptophan Decarboxylase in Different Subcellular Compartments in Tobacco Plant 被引量:2
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作者 王淼 李秋荣 +1 位作者 Stefano Di FIORE Rainer FISCHER 《Acta Botanica Sinica》 CSCD 2002年第3期314-317,共4页
The gene encoded for tryptophan decarboxylase (TDC), which is the key enzyme in terpenoil indole alkaloids pathway, was targeted to different subcellular compartments and stably expressed in transgenic tobacco (Nicoti... The gene encoded for tryptophan decarboxylase (TDC), which is the key enzyme in terpenoil indole alkaloids pathway, was targeted to different subcellular compartments and stably expressed in transgenic tobacco (Nicotiana tabacum L.) plants at the levels detected by Western blot and tryptamine accumulation analysis. It was shown that the TDC was located in subcellular compartments, the chloroplasts and cytosol. The recombinant TDC targeted to chloroplasts and cytosol in tobacco plants was effectively expressed as soluble protein by Western blot analysis and enzymatic assay. The level of tryptamine accumulation in chloroplast was higher than that in cytosol and very low in vacuole and endoplasmic reticulum (ER) to be hardly detected by Western blot analysis. It was indicated that the highest amount of tryptamine was in chloroplasts, lower in endoplasmic reticula and the lowest in vacuoles as compared to those in wild type plants. The TDC targeted to different subcellular compartments of tobacco plants and its expression level were studied by different nucleotide sequences coding signal peptides at 5'-end of tdc gene in order to know the effects of the TDC in compartmentation on its functionality. 展开更多
关键词 tryptophan decarboxylase alkaloids biosynthetic pathway Nicotiana tabacum subcellular compartment
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Response of Organic Acids to Zinc Homeostasis in Zinc-Deficient and Zinc-Toxic Apple Rootstock Roots 被引量:3
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作者 LIU Di LIU Ai-Hong +2 位作者 HE Chen WANG Jin-Hua WANG Yah-An 《Pedosphere》 SCIE CAS CSCD 2012年第6期803-814,共12页
To elucidate the mechanisms of tolerance to zinc (Zn) deficiency and Zn toxicity in the root of apple trees, the apple rootstock Malus hupehensis (Pamp.) Rehd seedlings were selected to study the responses of organic ... To elucidate the mechanisms of tolerance to zinc (Zn) deficiency and Zn toxicity in the root of apple trees, the apple rootstock Malus hupehensis (Pamp.) Rehd seedlings were selected to study the responses of organic acids to Zn homeostasis in roots under low Zn (0 μmol L-1 ), adequate Zn (as control, 4 μmol L-1 ) and toxic Zn (100 μmol L-1 ) treatments. The differences of Zn concentrations and accumulations in the roots were highest, compared with those in the stems and leaves, when apple seedlings were subjected to low and toxic Zn treatments for 1 d. The concentrations and accumulations of oxalic and malic acids in the roots in the low and toxic Zn treatments increased by 20% to 60% compared with those of the control treatment. Significantly negative correlations were found between the total Zn concentrations and the concentrations of oxalic and malic acids in the roots under 1 d of low Zn treatment. However, contrary correlations were found for the toxic Zn treatment. Meanwhile, the maximum influx rates of Zn 2+ under low and toxic Zn treatments increased by 30% and 20%, respectively, compared with the rate of the control treatment. Both Zn deficiency and Zn toxicity increased the concentrations of organic acids in root after short-time Zn treatment, which could resist Zn stress through balanding Zn homeostasis in M. hupehensis Rehd. 展开更多
关键词 Malus hupehensis (Pamp.) Rehd Zn compartmentation Zn deficiency Zn toxicity Zn uptake
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Synergistic effect of Si and K in improving the growth,ion distribution and partitioning of Lolium perenne L.under saline-alkali stress 被引量:2
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作者 FAN Yuan SHEN Wu-yan +1 位作者 Pino VANESSA CHENG Fang-qin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第6期1660-1673,共14页
The application of Si or K has proven to be beneficial for the growth of plants under saline-alkali stress. However, the synergistic effect of Si and K in improving the growth, ion distribution, and partitioning in Lo... The application of Si or K has proven to be beneficial for the growth of plants under saline-alkali stress. However, the synergistic effect of Si and K in improving the growth, ion distribution, and partitioning in Lolium perenne L. under saline-alkali stress remains unclear. In this study, the growth characteristics and ion-selective absorption of ryegrass(Lolium perenne L.) exposed to different levels of saline-alkali stress were evaluated. The growth parameters of ryegrass were significantly improved when Si was applied by itself or coupled with K under low saline-alkali stress. Under a high saline-alkali level, only simultaneous application of Si and K could significantly improve the growth of ryegrass. When Si and K were applied together, the K^(+)/Na^(+) and Ca^(2+)/Na^(+) ratios in root, stem, and leaf of ryegrass were maximally improved as compared to the individual treatments and control. The K^(+) and Ca^(2+) concentrations in the vacuole, cell wall, and organelle of leaf were increased dramatically. This improvement was due to the ability of applied ions to compete with Na^(+), allowing the plant to maintain osmotic potential and leaf water content. The concentration of Na^(+) was significantly reduced when Si and K were applied and mainly concentrated in the soluble fraction and cell wall. The Si concentration in ryegrass increased markedly by the combined application of Si and K, and most of it was accumulated in the cell wall and soluble fraction, which could help in chlorophyll synthesis, reduce membrane injury, and increase water absorption under saline-alkali stress. This study emphasized the advantage of Si and/or K on the growth of plants under different saline-alkaline levels and provided a guide for the production of Si-K fertilizer and its application in saline-alkali soil. 展开更多
关键词 saline-alkali stress SI K ryegrass plants K+/Na+ compartmentation
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Filamentation of Metabolic Enzymes in Saccharomyces cerevisiae 被引量:3
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作者 Qing-Ji Shen Hakimi Kassim +7 位作者 Yong Huang Hui Li Jing Zhang Guang Li Peng-Ye Wang Jun Yan Fangfu Ye Ji-Long Liu 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2016年第6期393-404,共12页
Compartmentation via filamentation has recently emerged as a novel mechanism for metabolic regulation. In order to identify filamentforming metabolic enzymes systematically, we performed a genome-wide screening of all... Compartmentation via filamentation has recently emerged as a novel mechanism for metabolic regulation. In order to identify filamentforming metabolic enzymes systematically, we performed a genome-wide screening of all strains available from an open reading frameGFP collection in Saccharomyces cerevisiae. We discovered nine novel filament-forming proteins and also confirmed those identified previously. From the 4159 strains, we found 23 proteins, mostly metabolic enzymes, which are capable of forming filaments in vivo. In silico protein-protein interaction analysis suggests that these filament-forming proteins can be clustered into several groups, including translational initiation machinery and glucose and nitrogen metabolic pathways. Using glutamine-utilising enzymes as examples, we found that the culture conditions affect the occurrence and length of the metabolic filaments. Furthermore, we found that two CTP synthases(Ura7p and Ura8p) and two asparagine synthetases(Asn1p and Asn2p) form filaments both in the cytoplasm and in the nucleus.Live imaging analyses suggest that metabolic filaments undergo sub-diffusion. Taken together, our genome-wide screening identifies additional filament-forming proteins in S. cerevisiae and suggests that filamentation of metabolic enzymes is more general than currently appreciated. 展开更多
关键词 CTP synthase Metabolic enzyme Cytoophidium Glycolysis Glutamine Intracellular compartmentation Saccharomyces cerevisiae
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PERTURBATION SOLUTION FOR COMPARTMENT MODEL OF VARIABLE EXTRACELLULAR VOLUME
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作者 张凤宝 张国亮 +1 位作者 李明 王淑兰 《Transactions of Tianjin University》 EI CAS 1997年第2期72-76,共5页
The two compartment model with variable extracellular volume is presented and solved by using both perturbation and analytical method. The computation for both creatinine and urea show that the perturbation solution ... The two compartment model with variable extracellular volume is presented and solved by using both perturbation and analytical method. The computation for both creatinine and urea show that the perturbation solution is not only simple but also accurate enough and is a good substitute for the more exact analytical solution. 展开更多
关键词 HEMODIALYSIS two compartment model ULTRAFILTRATION perturbation solution
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Expression of Strictosidine Synthase in Selected Subcellular Compartments of Tobacco Plant
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作者 王淼 李秋荣 +1 位作者 Stefano Di FIORE Rainer FISCHER 《Acta Botanica Sinica》 CSCD 2002年第5期579-582,共4页
Strictosidine synthase (STR) is a key enzyme involved in the biosynthesis of terpenoid indole alkaloids (TIA) by condensing tryptamine and secologanin into strictosidine. The transgenic tobacco plants targeting STR to... Strictosidine synthase (STR) is a key enzyme involved in the biosynthesis of terpenoid indole alkaloids (TIA) by condensing tryptamine and secologanin into strictosidine. The transgenic tobacco plants targeting STR to subcellular compartments were established to express STR in chloroplast, vacuole and endoplasmic reticulum (ER) by the tobacco stable transformation. It was shown that STR was effectively expressed in the above subcellular compartments by Western blot analysis and STR enzymatic assay. In vitro , STR enzymatic assay was measured indirectly by fluorimetrically detecting depletion of tryptamine feeding on secologanin in the reaction mixture. The tryptamine were completely depleted by STR in the crude extract of leaves of transgenic tobacco plants targeting and expressing STR in the chloroplast, vacuole and ER, which ascertained the STR functionally targeted to the three subcellular compartments. To confirm STR correct targeting and expressing in chloroplast, the chloroplasts were isolated and the fractions of purified chloroplasts were analyzed by Western blot. The hypothesis of STR correct targeting to the chloroplast was tested. The results have implications on our understanding of the complex intracellular trafficking in metabolic intermediates of TIA biosynthesis. 展开更多
关键词 Nicotiana tabacum strictosidine synthase subcellular compartment EXPRESSION
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