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1.
Sci Total Environ ; 918: 170284, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38266724

RESUMO

Multiple coexisting seasonal lakes are observed in the Poyang Lake basin. The interaction between surface water and groundwater, along with solute transport at the sediment-water interface (SWI), plays a crucial role in material cycling within the Poyang Lake ecosystem. However, the mechanisms governing how the relative positions of these lakes influence solute transport at the SWI remain unclear. This study employs indoor experiments and simulations based on real topography to investigate how the separation distance and elevation differences between two seasonal lakes, termed "lake A" (situated farther from the main lake) and "lake B" (closer to the main lake), affect solute transport. Findings highlight a distinct recharge pattern from lake A to lake B and the main lake during periodic water level fluctuations. A reduced distance between dual seasonal lakes results in a diminished water level drop in lake B during dry seasons. Proximity allows lake A to contribute more solutes to the main lake while promoting solute transport from lake B to the main lake, increasing the pore water recharge flux to overlying water in lake B. In cases where the separation distance has insufficient impact on water levels, the speed of pore water flow in this area inversely correlates with the distance between dual lakes. Reducing the distance intensifies solute transport into the bottom of lake A. Lower the elevation of lake B increases the water level difference between dual seasonal lakes, curtailing pollution within the lakebed. Elevating lake B forms hydrological isolation and more severe pollution of the lakebed. Solutes predominantly transport between lake B and the main lake, with pollution spreading to the lakebed of lake A and transitioning to downward diffusion over time. This research provides valuable insights for the hydraulic regulation of seasonal lakes and holds significance for the ecological restoration of Poyang Lake.

2.
Crit Rev Eukaryot Gene Expr ; 33(8): 57-75, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37606164

RESUMO

High-temperature requirement factor A3 (HTRA3), a member of the HTRA protein family, is closely associated with apoptosis and plays a crucial role in controlling signal transmission and cancer development. However, the regulatory pathways of HTRA3 in tumors are not fully understood, necessitating a comprehensive analysis of HTRA3 in cancers. In this study, we conducted a multi-omics analysis of HTRA3 in pan-cancer using data from various databases including TCGA, cBioPortal, GeneMANIA, DAVID, TIMER2.0, SangerBox, and RNAactDrug. Our analysis included gene expression, survival prognosis, diagnostic value, mutation, gene-gene interaction, enrichment analysis, and drug sensitivity analysis. We found that HTRA3 is aberrantly expressed in a variety of cancers and significantly correlates with diagnosis, prognosis, TMB, MSI, immune checkpoint (ICP) genes, and drug sensitivity in various cancer types. HTRA3 is involved in a variety of cancer pathways, particularly extracellular matrix (ECM) alterations, and has a potential role in epithelial-mesenchymal transition (EMT). HTRA3 expression is positively correlated with the abundance of cancer-associated fibroblasts (CAFs) and endothelial cells in the tumor microenvironment, and is also positively correlated with immune scores, stromal scores, and ESTIMATE scores in multiple cancers. HTRA3 is often overexpressed in cancer and is associated with poor prognosis and regulation of the tumor's immune response. Therefore, it may serve as a novel biomarker for tumor diagnosis and treatment.


Assuntos
Células Endoteliais , Neoplasias , Humanos , Prognóstico , Neoplasias/diagnóstico , Neoplasias/genética , Temperatura , Apoptose , Microambiente Tumoral/genética , Serina Endopeptidases/genética
3.
PLoS Comput Biol ; 13(7): e1005671, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28742153

RESUMO

Massive technological advances enabled high-throughput measurements of proteomic changes in biological processes. However, retrieving biological insights from large-scale protein dynamics data remains a challenging task. Here we used the mating differentiation in yeast Saccharomyces cerevisiae as a model and developed integrated experimental and computational approaches to analyze the proteomic dynamics during the process of cell fate determination. When exposed to a high dose of mating pheromone, the yeast cell undergoes growth arrest and forms a shmoo-like morphology; however, at intermediate doses, chemotropic elongated growth is initialized. To understand the gene regulatory networks that control this differentiation switch, we employed a high-throughput microfluidic imaging system that allows real-time and simultaneous measurements of cell growth and protein expression. Using kinetic modeling of protein dynamics, we classified the stimulus-dependent changes in protein abundance into two sources: global changes due to physiological alterations and gene-specific changes. A quantitative framework was proposed to decouple gene-specific regulatory modes from the growth-dependent global modulation of protein abundance. Based on the temporal patterns of gene-specific regulation, we established the network architectures underlying distinct cell fates using a reverse engineering method and uncovered the dose-dependent rewiring of gene regulatory network during mating differentiation. Furthermore, our results suggested a potential crosstalk between the pheromone response pathway and the target of rapamycin (TOR)-regulated ribosomal biogenesis pathway, which might underlie a cell differentiation switch in yeast mating response. In summary, our modeling approach addresses the distinct impacts of the global and gene-specific regulation on the control of protein dynamics and provides new insights into the mechanisms of cell fate determination. We anticipate that our integrated experimental and modeling strategies could be widely applicable to other biological systems.


Assuntos
Redes Reguladoras de Genes/genética , Modelos Biológicos , Feromônios/genética , Saccharomyces cerevisiae , Proteômica , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiologia , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
4.
Sci Rep ; 7: 42200, 2017 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-28181485

RESUMO

Motorized fluorescence microscopy combined with high-throughput microfluidic chips is a powerful method to obtain information about different biological processes in cell biology studies. Generally, to observe different strains under different environments, high-throughput microfluidic chips require complex preparatory work. In this study, we designed a novel and easily operated high-throughput microfluidic system to observe 96 different GFP-tagged yeast strains in one switchable culture condition or 24 different GFP-tagged yeast strains in four parallel switchable culture conditions. A multi-pipette is the only additional equipment required for high-throughput patterning of cells in the chip. Only eight connections are needed to control 96 conditions. Using these devices, the proteomic dynamics of the yeast stress response pathway were carefully studied based on single-cell data. A new method to characterize the proteomic dynamics using a single cell's data is proposed and compared to previous methods, and the new technique should be useful for studying underlying control networks. Our method provides an easy and systematic way to study signaling pathways at the single-cell level.


Assuntos
Osmorregulação/genética , Proteômica , Saccharomyces cerevisiae/genética , Análise de Célula Única/métodos , Ensaios de Triagem em Larga Escala , Dispositivos Lab-On-A-Chip , Transdução de Sinais
5.
Integr Biol (Camb) ; 8(6): 712-9, 2016 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-27177258

RESUMO

Microfluidics, in combination with time-lapse microscopy, is a transformative technology that significantly enhances our ability to monitor and probe biological processes in living cells. However, high-throughput microfluidic devices mostly require sophisticated preparatory and setup work and are thus hard to adopt by non-experts. In this work, we designed an easy-to-use microfluidic chip, which enables tracking of 48 GFP-tagged yeast strains, with each strain under two different stimulus conditions, in a single experiment. We used this technology to investigate the dynamic pattern of protein expression during the yeast mating differentiation response. High doses of pheromone induce cell cycle arrest and the shmoo morphology, whereas low doses of pheromone lead to elongation and chemotrophic growth. By systematically analyzing the protein dynamics of 156 pheromone-regulated genes, we identified groups of genes that are preferentially induced in response to low-dose pheromone (elongation during growth) or high-dose pheromone (shmoo formation and cell cycle arrest). The protein dynamics of these genes may provide insights into the mechanisms underlying the differentiation switch induced by different doses of pheromone.


Assuntos
Regulação Fúngica da Expressão Gênica/fisiologia , Dispositivos Lab-On-A-Chip , Feromônios/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/fisiologia , Análise Serial de Tecidos/instrumentação , Pontos de Checagem do Ciclo Celular/fisiologia , Diferenciação Celular/fisiologia , Tamanho Celular , Desenho de Equipamento , Mitose/fisiologia , Saccharomyces cerevisiae/citologia
6.
Integr Biol (Camb) ; 6(7): 685-93, 2014 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-24872017

RESUMO

Time-lapse single cell imaging by microscopy can provide precise cell information such as the cell size, the cell cycle duration, protein localization and protein expression level. Usually, a microfluidic system is needed for these measurements in order to provide a constant culture environment and confine the cells so that they grow in a monolayer. However, complex connections are required between the channels inside the chip and the outside media, and a complex procedure is needed for loading of cells, thereby making this type of system unsuitable for application in high-throughput single cell scanning experiments. Here we provide a novel and easily operated pump-free multi-well-based microfluidic system which enables the high-throughput loading of many different budding yeast strains into monolayer growth conditions just by use of a multi-channel pipette. Wild type budding yeast (Saccharomyces cerevisiae) and 62 different budding yeast size control relative gene deletion strains were chosen for scanning. We obtained normalized statistical results for the mother cell doubling time, daughter cell doubling time, mother cell size and daughter cell size of different gene deletion strains relative to the corresponding parameters of the wild type cells. Meanwhile, we compared the typical cell morphology of different strains and analyzed the relationship between the cell genotype and phenotype. This method which can be easily used in a normal biology lab may help researchers who need to carry out the high-throughput scanning of cell morphology and growth.


Assuntos
Ciclo Celular/fisiologia , Divisão Celular/fisiologia , Saccharomycetales/fisiologia , Microfluídica/instrumentação , Microfluídica/métodos , Saccharomycetales/ultraestrutura , Imagem com Lapso de Tempo
7.
ASAIO J ; 51(6): 736-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16340359

RESUMO

To provide better anatomical fit and physiologic adaptation, three aortic valvo-pumps with different dimensions were developed. Each pump has a rotor with an impeller and drive magnets and a stator consisting of a motor coil with iron core and an outflow guide vane. The devices had outer diameters of 21 mm, 23 mm, and 25 mm, respectively, and weighted 27 g, 31 g, and 40 g, respectively. Laboratory testing demonstrated that the rotating speed for maintaining a diastolic pressure of 80 mm Hg at zero flow rate should be 17500 rpm, 15000 rpm, and 12500 rpm, respectively; the largest flow at these same speeds will be 5 l/min, 7 l/min, and 10 l/min, respectively, with approximately 50 mm Hg pressure head increase. Therefore, these three pumps may meet the hemodynamic requirements of patients with body weights of 40-60 kg, 60-80 kg, and 80-100 kg. The first in vivo trial exhibited that the 25 mm valvo-pump can be sewn onto the aortic valve annulus of a 80 kg body weight pig without harm to adjacent organ functions. The devices occupy no additional anatomic space and deliver the blood directly from ventricle to the aorta, thus producing less physiologic disturbance to the natural circulation. Neither connecting conduits nor bypass circuits are necessary, thus eliminating the most dangerous sites of thrombosis in traditional left ventricular assist devices.


Assuntos
Coração Auxiliar , Animais , Valva Aórtica/cirurgia , Engenharia Biomédica , Humanos , Desenho de Prótese , Suínos
8.
Zhongguo Yi Liao Qi Xie Za Zhi ; 29(4): 238-40, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16268344

RESUMO

Since 1995, four different types of artificial heart pumps and artificial valvo-pumps have been developed in Jiangsu University of China. Three types of heart pumps and valvo-pumps have been applied in animal experiments in University Texas, Medical Branch, USA and in Zhenjiang No.1 People's Hospital of China. The recently-developed UJS-IV pump is a totally implantable trans-ventricular and cross-valvular pump for emergercy treatments.


Assuntos
Próteses Valvulares Cardíacas , Coração Artificial , Desenho de Equipamento , Coração Auxiliar
9.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 20(3): 534-6, 2003 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-14565033

RESUMO

For long-term application of the rotary pumps, it is necessary to solve the problems of bearing wear and thrombosis along the bearing. Currently, many investigators choose the magnetic bearing to realize zero-friction and no contact between the rotor and stator; the former avoids the mechanical wear and the latter eliminates the possibility of thrombus formation. We tried and found that it is difficult to apply a magnetic bearing to rotary pump without disturbing its simplicity, reliability and implantable; therefore, we have developed a much simpler and much more creative approach to achieving the same results. Instead of the sliding bearing, a rolling bearing has been devised for the pump; its friction is about 1/15 of the sliding bearing. Furthermore, a wear-proof material of ultra-high-molecular weight polythene has been adopted in making the rollers, their anti-wear property in 8 times better than that of metal. Thereby, the service life of the bearing has extended to several years. For preventing the thrombus formation along the bearing, the impeller reciprocation axially as the impeller changes its rotating speed periodically to produce a pulsatile flow. The reciprocation is a result of the effects of a magnetic force between the motor rotor and stator, and a hydraulic force between the blood flow and the impeller. Similar to piston pump, the oscillating impeller can make the blood in and out of the bearing, resulting in wash-out once a circle. This is obviously beneficial to preventing thrombosis along the bearing and in the pump. The endurance tests with saline of this novel pump demonstrated a durability of the device. It promises to be able to assist the circulation of the patients permanently and to be able to replace the heart transplantation in the future.


Assuntos
Coração Auxiliar , Magnetismo/instrumentação , Trombose/prevenção & controle , Desenho de Prótese
10.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 20(4): 605-7, 2003 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-14716856

RESUMO

To evaluate the effect of impeller design on pump hemolysis, five impellers with different number of vanes or different vane angles were manufactured and tested in one pump for hemolysis comparison. The impellers are made to have the same dimension and same logarithmic spiral vane from which coincide with the stream surfaces in the pump, according to the analytical and three-dimensional design method developed by the authors. Consequently, an impeller with 6 vanes and 30 degrees vane angle has the lowest hemolysis index. This result agrees with the theoretical analyses of other investigators searching optimal number of vanes and vane angle to achieve the highest efficiency of the pump.


Assuntos
Coração Auxiliar , Coração Auxiliar/efeitos adversos , Hemólise , Humanos , Técnicas In Vitro , Desenho de Prótese
11.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 19(4): 593-5, 2002 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-12561356

RESUMO

Magnetic bearing has no mechanical contact between the rotor and stator. And a rotary pump with magnetic bearing has therefore no mechanical wear and thrombosis due to bearing. The available magnetic bearings, however, are devised with electric magnets, need complicated control and remarkable energy consumption. Resultantly, it is difficult to apply an electric magnetic bearing to rotary pump without disturbing its simplicity, implantability and reliability. The authors have developed a levitated impeller pump merely with permanent magnets. The rotor is supported by permanent magnetic forces radially. On one side of the rotor, the impeller is fixed; and on the other side of the rotor, the driven magnets are mounted. Opposite to this driven magnets, a driving motor coil with iron corn magnets is fastened to the motor axis. Thereafter, the motor drives the rotor via a rotating magnetic field. By laboratory tests with saline, if the rotor stands still or rotates under 4,000 rpm, the rotor has one-point contact axially with the driving motor coil. The contacting point is located in the center of the rotor. As the rotating speed increases gradually to more than 4,000 rpm, the rotor will detache from the stator axially. Then the rotor will be fully levitated. Since the axial levitation is produced by hydraulic force and the driven magnets have a gyro-effect, the rotor rotates very steadly during levitation. As a left ventricular assist device, the pump works in a rotating speed range of 5,000-8,000 rpm, the levitation of the impeller hence is ensured by practical use of the pump.


Assuntos
Coração Auxiliar , Magnetismo/instrumentação , Desenho de Equipamento
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