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1.
Molecules ; 29(8)2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38675568

ABSTRACT

Reactions of Co(OAc)2·4H2O, N'N'-bis(3-pyridylmethyl)oxalamide (L) and 4,4'-sulfonyldibenzoic acid (H2SDA) afforded four coordination polymers with the same mixed ligands, {[Co(L)(SDA)(H2O)2]·H2O·CH3OH}n, 1, {[Co(L)0.5(SDA)]·2H2O·0.5L}n, 2, {[Co(L)1.5(SDA)(H2O)]·H2O}n, 3, and {[Co2(L)1.5(SDA)2(H2O)2]·4H2O}n, 4, which have been structurally characterized using single-crystal X-ray crystallography. Complexes 1-4 are 2D layers, revealing topologies of sql, 2,6L1, (4,4)Ia, and 6L12, respectively, and demonstrating that the metal-to-ligand ratio, solvent system, and reaction temperature are important in determining the structural diversity. The immersion of these complexes into various solvents shows that the structural types govern the chemical stabilities of 1-4. Reversible structural transformation is shown for complexes 1 and 2 upon solvent removal and adsorption, while those of 3 and 4 are irreversible.

2.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 40(5): 1019-1026, 2023 Oct 25.
Article in Zh | MEDLINE | ID: mdl-37879933

ABSTRACT

Myocardial infarction (MI) has the characteristics of high mortality rate, strong suddenness and invisibility. There are problems such as the delayed diagnosis, misdiagnosis and missed diagnosis in clinical practice. Electrocardiogram (ECG) examination is the simplest and fastest way to diagnose MI. The research on MI intelligent auxiliary diagnosis based on ECG is of great significance. On the basis of the pathophysiological mechanism of MI and characteristic changes in ECG, feature point extraction and morphology recognition of ECG, along with intelligent auxiliary diagnosis method of MI based on machine learning and deep learning are all summarized. The models, datasets, the number of ECG, the number of leads, input modes, evaluation methods and effects of different methods are compared. Finally, future research directions and development trends are pointed out, including data enhancement of MI, feature points and dynamic features extraction of ECG, the generalization and clinical interpretability of models, which are expected to provide references for researchers in related fields of MI intelligent auxiliary diagnosis.


Subject(s)
Electrocardiography , Myocardial Infarction , Humans , Myocardial Infarction/diagnosis , Recognition, Psychology
3.
Crit Rev Biotechnol ; 40(8): 1232-1249, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32907412

ABSTRACT

In recent years, there has been increasing interest in microbial biotechnology for the production of value-added compounds from renewable resources. Pseudomonas species have been proposed as a suitable workhorse for high-value secondary metabolite production because of their unique characteristics for fast growth on sustainable carbon sources, a clear inherited background, versatile intrinsic metabolism with diverse enzymatic capacities, and their robustness in an extreme environment. It has also been demonstrated that metabolically engineered Pseudomonas strains can produce several industrially valuable aromatic chemicals and natural products such as phenazines, polyhydroxyalkanoates, rhamnolipids, and insecticidal proteins from renewable feedstocks with remarkably high yields suitable for commercial application. In this review, we summarize cell factory construction in Pseudomonas for the biosynthesis of native and non-native bioactive compounds in P. putida, P. chlororaphis, P. aeruginosa, as well as pharmaceutical proteins production by P. fluorescens. Additionally, some novel strategies together with metabolic engineering strategies in order to improve the biosynthetic abilities of Pseudomonas as an ideal chassis are discussed. Finally, we proposed emerging opportunities, challenges, and essential strategies to enable the successful development of Pseudomonas as versatile microbial cell factories for the bioproduction of diverse bioactive compounds.


Subject(s)
Industrial Microbiology , Metabolic Engineering , Pseudomonas/metabolism , Biological Products , Glycolipids , Insecticides , Phenazines , Polyhydroxyalkanoates , Secondary Metabolism , Synthetic Biology
4.
Article in English | MEDLINE | ID: mdl-32809044

ABSTRACT

The cathode ray tube (CRT) is a common and important tool that has been in use for decades, with which behavioral and visual neuroscientists deliver specific visual images generated by computers. Considering the operating principle of the CRT, the image it presents can flick at a constant rate, which will introduce distractions to the visual experiments on subjects with higher temporal resolutions. While this entrainment has been proved common in recordings of the primary visual cortex of mammals, it is uncertain whether it also exists in the intermediate to deep layers of pigeon's optic tectum, which is relevant to the spatial attention. Here, we present continuous visual stimuli with different refresh rates and luminances couples shown on a CRT to pigeons. The recordings in the intermediate to deep layers of optic tectum were significantly phase locking to the refresh of the CRT, and lower refresh rates of the CRT with higher brightness more likely introduced artifacts in electrophysiological recordings of pigeons, which may seriously damage their visual information perception.


Subject(s)
Columbidae/physiology , Neurons/physiology , Photic Stimulation/methods , Superior Colliculi/physiology , Vision, Ocular/physiology , Visual Cortex/physiology , Visual Perception/physiology , Animals
5.
J Synchrotron Radiat ; 25(Pt 1): 166-176, 2018 Jan 01.
Article in English | MEDLINE | ID: mdl-29271766

ABSTRACT

High-brightness X-ray free-electron lasers (FELs) are perceived as fourth-generation light sources providing unprecedented capabilities for frontier scientific researches in many fields. Thin crystals are important to generate coherent seeds in the self-seeding configuration, provide precise spectral measurements, and split X-ray FEL pulses, etc. In all of these applications a high-intensity X-ray FEL pulse impinges on the thin crystal and deposits a certain amount of heat load, potentially impairing the performance. In the present paper, transient thermal stress wave and vibrational analyses as well as transient thermal analysis are carried out to address the thermomechanical issues for thin diamond crystals, especially under high-repetition-rate operation of an X-ray FEL. The material properties at elevated temperatures are considered. It is shown that, for a typical FEL pulse depositing tens of microjoules energy over a spot of tens of micrometers in radius, the stress wave emission is completed on the tens of nanoseconds scale. The amount of kinetic energy converted from a FEL pulse can reach up to ∼10 nJ depending on the layer thickness. Natural frequencies of a diamond plate are also computed. The potential vibrational amplitude is estimated as a function of frequency. Due to the decreasing heat conductivity with increasing temperature, a runaway temperature rise is predicted for high repetition rates where the temperature rises abruptly after ratcheting up to a point of trivial heat damping rate relative to heat deposition rate.

6.
Microb Cell Fact ; 17(1): 174, 2018 Nov 10.
Article in English | MEDLINE | ID: mdl-30414616

ABSTRACT

BACKGROUND: Arbutin is a plant-derived glycoside with potential antioxidant, antibacterial and anti-inflammatory activities. Currently, it is mainly produced by plant extraction or enzymatic processes, which suffers from expensive processing cost and low product yield. Metabolic engineering of microbes is an increasingly powerful method for the high-level production of valuable biologicals. Since Pseudomonas chlororaphis has been widely engineered as a phenazine-producing platform organism due to its well-characterized genetics and physiology, and faster growth rate using glycerol as a renewable carbon source, it can also be engineered as the cell factory using strong shikimate pathway on the basis of synthetic biology. RESULTS: In this work, a plasmid-free biosynthetic pathway was constructed in P. chlororaphis P3 for elevated biosynthesis of arbutin from sustainable carbon sources. The arbutin biosynthetic pathway was expressed under the native promoter Pphz using chromosomal integration. Instead of being plasmid and inducer dependent, the metabolic engineering approach used to fine-tune the biosynthetic pathway significantly enhanced the arbutin production with a 22.4-fold increase. On the basis of medium factor optimization and mixed fed-batch fermentation of glucose and 4-hydroxybenzoic acid, the engineered P. chlororaphis P3-Ar5 strain led to the highest arbutin production of 6.79 g/L with the productivity of 0.094 g/L/h, with a 54-fold improvement over the initial strain. CONCLUSIONS: The results suggested that the construction of plasmid-free synthetic pathway displays a high potential for improved biosynthesis of arbutin and other shikimate pathway derived biologicals in P. chlororaphis.


Subject(s)
Arbutin/biosynthesis , Metabolic Engineering/methods , Pseudomonas chlororaphis/metabolism , Shikimic Acid/metabolism , Arbutin/chemistry , Biosynthetic Pathways/drug effects , Carbon/pharmacology , Genes, Bacterial , Glucose/pharmacology , Glycerol/metabolism , Kinetics , Parabens/chemistry , Parabens/metabolism , Pseudomonas chlororaphis/drug effects , Pseudomonas chlororaphis/genetics , Pseudomonas chlororaphis/growth & development
7.
Appl Microbiol Biotechnol ; 102(8): 3561-3571, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29516141

ABSTRACT

4-Hydroxybenzoic acid (4-HBA) has recently emerged as a promising intermediate for several value-added bioproducts with potential biotechnological applications in food, cosmetics, pharmacy, fungicides, etc. Over the past years, a variety of biosynthetic techniques have been developed for producing the 4-HBA and 4-HBA-based products. At this juncture, synthetic biology and metabolic engineering approaches enabled the biosynthesis of 4-HBA to address the increasing demand for high-value bioproducts. This review summarizes the biosynthesis of a variety of industrially pertinent compounds such as resveratrol, muconic acid, gastrodin, xiamenmycin, and vanillyl alcohol using 4-HBA as the starting feedstock. Moreover, potential research activities with a close-up look at the future perspectives to produce new compounds using 4-HBA have also been discussed.


Subject(s)
Chemistry Techniques, Synthetic/trends , Parabens/chemistry , Metabolic Engineering
8.
Appl Microbiol Biotechnol ; 102(18): 7759-7773, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30014168

ABSTRACT

Shikimic acid is an important intermediate for the manufacture of the antiviral drug oseltamivir (Tamiflu®) and many other pharmaceutical compounds. Much of its existing supply is obtained from the seeds of Chinese star anise (Illicium verum). Nevertheless, plants cannot supply a stable source of affordable shikimate along with laborious and cost-expensive extraction and purification process. Microbial biosynthesis of shikimate through metabolic engineering and synthetic biology approaches represents a sustainable, cost-efficient, and environmentally friendly route than plant-based methods. Metabolic engineering allows elevated shikimate production titer by inactivating the competing pathways, increasing intracellular level of key precursors, and overexpressing rate-limiting enzymes. The development of synthetic and systems biology-based novel technologies have revealed a new roadmap for the construction of high shikimate-producing strains. This review elaborates the enhanced biosynthesis of shikimate by utilizing an array of traditional metabolic engineering along with novel advanced technologies. The first part of the review is focused on the mechanistic pathway for shikimate production, use of recombinant and engineered strains, improving metabolic flux through the shikimate pathway, chemically inducible chromosomal evolution, and bioprocess engineering strategies. The second part discusses a variety of industrially pertinent compounds derived from shikimate with special reference to aromatic amino acids and phenazine compound, and main engineering strategies for their production in diverse bacterial strains. Towards the end, the work is wrapped up with concluding remarks and future considerations.


Subject(s)
Bacteria/genetics , Bacteria/metabolism , Industrial Microbiology/trends , Metabolic Engineering , Shikimic Acid/metabolism
9.
FEMS Yeast Res ; 16(4)2016 06.
Article in English | MEDLINE | ID: mdl-27189360

ABSTRACT

Promoter of alcohol oxidase I (PAOX1) is the most efficient promoter involved in the regulation of recombinant protein expression in Pichia pastoris (P. pastoris). PAOX1 is tightly repressed by the presence of glycerol in the culture medium; thus, glycerol must be exhausted before methanol can be taken up by P. pastoris and the expression of the heterologous protein can be induced. In this study, a candidate glycerol transporter (GT1, GeneID: 8197545) was identified, and its role was confirmed by further studies (e.g. bioinformatics analysis, heterologous complementation in Schizosaccharomyces pombe (S. pombe)). When GT1 is co-expressed with enhanced green fluorescent protein (EGFP), it localizes to the membrane and S. pombe carrying gt1 but not the wild-type strain can grow on medium containing glycerol as the sole carbon source. The present study is the first to report that AOX1 in the X-33Δgt1 mutant can achieve constitutive expression in medium containing glycerol; thus, knocking down gt1 can eliminate the glycerol repression of PAOX1 in P. pastoris These results suggest that the glycerol transporter may participate in the process of PAOX1 inhibition in glycerol medium.


Subject(s)
Alcohol Oxidoreductases/biosynthesis , Gene Expression Regulation, Fungal/drug effects , Glycerol/metabolism , Membrane Transport Proteins/metabolism , Pichia/metabolism , Membrane Transport Proteins/genetics , Pichia/genetics
10.
Tree Physiol ; 44(4)2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38412116

ABSTRACT

Residual canopy transpiration (Emin_canop) is a key physiological trait that determines trees' survival time under drought after stomatal closure and after trees have limited access to soil water. Emin_canop mainly depends on leaf minimum conductance (gmin) and vapor pressure deficit. Here we determined the seasonal variation of gmin and how gmin is related to interspecies variation in leaf cuticular and stomatal traits for nine European tree species in a mature forest. In addition, we determined the species-specific temperature responses of gmin. With this newly obtained insight, we calculated Emin_canop for the nine species for one day at our research site during the 2022 central European hot drought. Our results show that at ambient temperatures gmin ranged from 0.8 to 4.8 mmol m-2 s-1 across the nine species and was stable in most species throughout the growing season. The interspecies variation of gmin was associated with leaf cuticular and stomatal traits. Additionally, gmin exhibited strong temperature responses and increased, depending on species, by a factor of two to four in the range of 25-50 °C. For the studied species at the site, during a single hot drought day, Emin_canop standardized by tree size (stem basal area) ranged from 2.0 to 36.7 L m-2, and non-standardized Emin_canop for adult trees ranged from 0.3 to 5.3 L. Emin_canop also exhibited species-specific rapid increases under hotter temperatures. Our results suggest that trees, depending on species, need reasonable amounts of water during a drought, even when stomates are fully closed. Species differences in gmin and ultimately Emin_canop can, together with other traits, affect the ability of a tree to keep its tissue hydrated during a drought and is likely to contribute to species-specific differences in drought vulnerability.


Subject(s)
Trees , Water , Trees/physiology , Water/physiology , Droughts , Plant Leaves/physiology , Forests
11.
Integr Zool ; 19(2): 288-306, 2024 Mar.
Article in English | MEDLINE | ID: mdl-36893724

ABSTRACT

Food and predators are the most noteworthy objects for the basic survival of wild animals, and both are often deviant in both spatial and temporal domains and quickly attract an animal's attention. Although stimulus-specific adaptation (SSA) is considered a potential neural basis of salient sound detection in the temporal domain, related research on visual SSA is limited and its relationship with temporal saliency is uncertain. The avian nucleus isthmi pars magnocellularis (Imc), which is central to midbrain selective attention network, is an ideal site to investigate the neural correlate of visual SSA and detection of a salient object in the time domain. Here, the constant order paradigm was applied to explore the visual SSA in the Imc of pigeons. The results showed that the firing rates of Imc neurons gradually decrease with repetitions of motion in the same direction, but recover when a motion in a deviant direction is presented, implying visual SSA to the direction of a moving object. Furthermore, enhanced response for an object moving in other directions that were not presented ever in the paradigm is also observed. To verify the neural mechanism underlying these phenomena, we introduced a neural computation model involving a recoverable synaptic change with a "center-surround" pattern to reproduce the visual SSA and temporal saliency for the moving object. These results suggest that the Imc produces visual SSA to motion direction, allowing temporal salient object detection, which may facilitate the detection of the sudden appearance of a predator.


Subject(s)
Mesencephalon , Neurons , Animals , Mesencephalon/physiology , Neurons/physiology , Columbidae , Photic Stimulation
12.
Stem Cell Res Ther ; 15(1): 274, 2024 Sep 02.
Article in English | MEDLINE | ID: mdl-39218930

ABSTRACT

BACKGROUND: Understanding the lineage differentiation of human prostate not only is crucial for basic research on human developmental biology but also significantly contributes to the management of prostate-related disorders. Current knowledge mainly relies on studies on rodent models, lacking human-derived alternatives despite clinical samples may provide a snapshot at certain stage. Human embryonic stem cells can generate all the embryonic lineages including the prostate, and indeed a few studies demonstrate such possibility based on co-culture or co-transplantation with urogenital mesenchyme into mouse renal capsule. METHODS: To establish a stepwise protocol to obtain prostatic organoids in vitro from human embryonic stem cells, we apply chemicals and growth factors by mimicking the regulation network of transcription factors and signal transduction pathways, and construct cell lines carrying an inducible NKX3-1 expressing cassette, together with three-dimensional culture system. Unpaired t test was applied for statistical analyses. RESULTS: We first successfully generate the definitive endoderm, hindgut, and urogenital sinus cells. The embryonic stem cell-derived urogenital sinus cells express prostatic key transcription factors AR and FOXA1, but fail to express NKX3-1. Therefore, we construct NKX3-1-inducible cell line by homologous recombination, which is eventually able to yield AR, FOXA1, and NKX3-1 triple-positive urogenital prostatic lineage cells through stepwise differentiation. Finally, combined with 3D culture we successfully derive prostate-like organoids with certain structures and prostatic cell populations. CONCLUSIONS: This study reveals the crucial role of NKX3-1 in prostatic differentiation and offers the inducible NKX3-1 cell line, as well as provides a stepwise differentiation protocol to generate human prostate-like organoids, which should facilitate the studies on prostate development and disease pathogenesis.


Subject(s)
Cell Differentiation , Cell Lineage , Homeodomain Proteins , Human Embryonic Stem Cells , Prostate , Transcription Factors , Humans , Prostate/cytology , Prostate/metabolism , Human Embryonic Stem Cells/metabolism , Human Embryonic Stem Cells/cytology , Transcription Factors/metabolism , Transcription Factors/genetics , Male , Homeodomain Proteins/metabolism , Homeodomain Proteins/genetics , Organoids/metabolism , Organoids/cytology , Mice , Hepatocyte Nuclear Factor 3-alpha/metabolism , Hepatocyte Nuclear Factor 3-alpha/genetics , Animals , Cell Line
13.
Huan Jing Ke Xue ; 45(3): 1274-1284, 2024 Mar 08.
Article in Zh | MEDLINE | ID: mdl-38471844

ABSTRACT

Climate warming and air pollution are the main environmental problems in China. This study used China's Carbon Accounting Database, energy economic model, and air quality model to analyze the potential carbon emission peaking path and synergistic air quality improvement gain in the industrial sector in Hunan Province. Based on China's Carbon Accounting Database and the local industry/energy statistical yearbooks in Hunan, the total CO2 emissions in Hunan Province in 2019 were 310.6 Mt, of which the industrial sector accounted for over 70% of the emissions, mainly from the production and supply of electricity, steam, and heat; the production of non-metallic minerals; and the smelting and pressing of ferrous metals. Three potential industrial carbon emission peaking scenarios were analyzed using the LEAP energy economic model, including the business-as-usual scenario (peaking by 2030), moderate emission reduction scenario (peaking by 2028), and aggressive emission reduction scenario (peaking by 2025), by employing different economic growth rates, energy technology progress, and energy structures of the industrial sector. Furthermore, by combining the anthropogenic air pollutant emission inventory and the regional air quality model WRF-Chem, we analyzed the air quality improvement associated with various carbon emission peak paths. The results showed that the annual mean concentrations of major air pollutants had decreased in the three scenarios, especially in the Chang-Zhu-Tan Region. The aggressive emission reduction scenario was the most effective scenario, followed by the moderate emission reduction scenario and the business-as-usual scenario. Manufacturing was the sector with the most significant synergistic effect of pollution and carbon reduction. When carbon emission peaks were achieved, the annual average concentrations of PM2.5 and PM10 in Hunan Province could be synergistically reduced by 0.6-1.8 µg·m-3 and 1.8-8.9 µg·m-3, respectively. Our findings offer important insights into carbon emission peaking and can provide useful information for potential mitigation actions.

14.
MedComm (2020) ; 5(6): e568, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38756440

ABSTRACT

Parkinson's disease (PD) is a mitochondria-related neurodegenerative disease characterized by locomotor deficits and loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNc). Majority of PD research primarily focused on neuronal dysfunction, while the roles of astrocytes and their mitochondria remain largely unexplored. To bridge the gap and investigate the roles of astrocytic mitochondria in PD progression, we constructed a specialized optogenetic tool, mitochondrial-targeted anion channelrhodopsin, to manipulate mitochondrial membrane potential in astrocytes. Utilizing this tool, the depolarization of astrocytic mitochondria within the SNc in vivo led to the accumulation of γ-aminobutyric acid (GABA) and glutamate in SNc, subsequently resulting in excitatory/inhibitory imbalance and locomotor deficits. Consequently, in vivo calcium imaging and interventions of neurotransmitter antagonists demonstrated that GABA accumulation mediated movement deficits of mice. Furthermore, 1 h/day intermittent astrocytic mitochondrial depolarization for 2 weeks triggered spontaneous locomotor dysfunction, α-synuclein aggregation, and the loss of DA neurons, suggesting that astrocytic mitochondrial depolarization was sufficient to induce a PD-like phenotype. In summary, our findings suggest the maintenance of proper astrocytic mitochondrial function and the reinstatement of a balanced neurotransmitter profile may provide a new angle for mitigating neuronal dysfunction during the initial phases of PD.

15.
Materials (Basel) ; 16(6)2023 Mar 07.
Article in English | MEDLINE | ID: mdl-36984027

ABSTRACT

The thin-wall heat pipe is an efficient heat transfer component that has been widely used in the field of heat dissipation of high-power electronic equipment in recent years. In this study, the orange peel morphology defect of thin-wall heat pipes after bending deformation was analyzed both for the macro-3D profile and for the micro-formation mechanism. The morphology and crystal orientations of the grains and annealing twins were carefully characterized utilizing optical metallography and the electron backscatter diffraction technique. The results show that after high-temperature sintering treatment, the matrix grains of the heat pipe are seriously coarsened and form a strong Goss texture, while certain annealing twins with the unique copper orientation are retained. The distribution of the Schmid factor value subjected to the uniaxial stress indicates that inhomogeneity in the intergranular deformation exists among the annealing twins and matrix grains. The annealing twin exhibits a "hard-oriented" component during the deformation; thus, it plays a role as a barrier and hinders the slipping of dislocation. As the strain accumulates, part of the annealing twins may protrude from the surface of the heat pipe, forming a large-scale fluctuation of the surface as the so-called "orange peel" morphology. The 3D profile shows the bulged twins mostly perpendicular to the drawing direction, about 200-300 in width and 10-20 µm in height.

16.
Materials (Basel) ; 16(11)2023 May 31.
Article in English | MEDLINE | ID: mdl-37297239

ABSTRACT

A Cu-2.35Ni-0.69Si alloy with low La content was designed in order to study the role of La addition on microstructure evolution and comprehensive properties. The results indicate that the La element demonstrates a superior ability to combine with Ni and Si elements, via the formation of La-rich primary phases. Owing to existing La-rich primary phases, restricted grain growth was observed, due to the pinning effect during solid solution treatment. It was found that the activation energy of the Ni2Si phase precipitation decreased with the addition of La. Interestingly, the aggregation and distribution of the Ni2Si phase, around the La-rich phase, was observed during the aging process, owing to the attraction of Ni and Si atoms by the La-rich phase during the solid solution. Moreover, the mechanical and conductivity properties of aged alloy sheets suggest that the addition of the La element showed a slight reducing effect on the hardness and electrical conductivity. The decrease in hardness was due to the weakened dispersion and strengthening effect of the Ni2Si phase, while the decrease in electrical conductivity was due to the enhanced scattering of electrons by grain boundaries, caused by grain refinement. More notably, excellent thermal stabilities, including better softening resistance ability and microstructural stability, were detected for the low-La-alloyed Cu-Ni-Si sheet, owing to the delayed recrystallization and restricted grain growth caused by the La-rich phases.

17.
Nanoscale ; 15(4): 1583-1594, 2023 Jan 27.
Article in English | MEDLINE | ID: mdl-36594591

ABSTRACT

Engineered magnetic nanoparticles combining diagnosis and therapy functions into one entity hold great potential to rejuvenate cancer treatment; however, they are still constrained by the "always on" signals and unsatisfactory therapeutic effect. Here, we report an intelligent theranostic probe based on Mn3O4 tetragonal bipyramids (MnTBs), which simultaneously respond to H+ and glutathione (GSH) with high sensitivity and quickly decompose to release Mn2+ in mild acidic and reductive intracellular environments. Mn2+ binds to the surrounding proteins to achieve a remarkable relaxivity amplification and selectively brighten the tumors. Particularly, this MR signal improvement is also effective in the detection of millimeter-sized liver metastases, with an ultrahigh contrast of 316%. Moreover, Mn2+ would trigger chemodynamic therapy (CDT) by exerting the Fenton-like activity to generate ˙OH from H2O2. Subsequently, a significant tumor suppression effect can be achieved by the GSH depletion-enhanced CDT. Besides, MnTBs manifest efficient urinary and hepatic excretions with biodegradability and minimal systemic toxicity. A pH/GSH dual responsive nanoprobe that integrates tumor diagnostic and therapeutic activities was developed to provide a new paradigm for precise diagnosis and treatment of tumors and metastases.


Subject(s)
Nanoparticles , Neoplasms , Humans , Cell Line, Tumor , Hydrogen Peroxide/metabolism , Neoplasms/drug therapy , Nanoparticles/therapeutic use , Glutathione/metabolism , Magnetic Resonance Imaging , Hydrogen-Ion Concentration , Tumor Microenvironment
18.
Huan Jing Ke Xue ; 44(10): 5443-5455, 2023 Oct 08.
Article in Zh | MEDLINE | ID: mdl-37827762

ABSTRACT

Carbon emission peaking and air quality improvement is an urgent issue in the research of the atmospheric environment. Here, the emission factor method was used to compile the city-level greenhouse gas emission inventory of Jiangsu Province from 2010 to 2019, which was then combined with greenhouse gas-air pollutant synergy analysis and WRF-Chem air quality model simulation to analyze the synergistic gain of air quality improvement under different carbon emission reduction scenarios. The results revealed that the annual mean CO2 emission in Jiangsu Province from 2010 to 2019 was 701.74-897.47 Mt. Suzhou, Xuzhou, and Nanjing had the highest emissions (91.19-182.12 Mt·a-1); Yangzhou, Suqian, and Lianyungang had the lowest emissions (13.19-32.54 Mt·a-1); and majority of the cities had a continuous upward trend in the CO2 emissions. Energy activities were the main source of CO2 emissions, accounting for nearly 90%, whereas industrial production processes contributed to the remaining 10%. This study designed three types of CO2 emission reduction conditions according to different emission reduction priorities, namely, sector-wide collaborative, energy priority, and industrial priority. Each type of emission reduction condition included a different intensity of CO2 emission reduction (10%, 20%, and 40%). The condition-based simulation results demonstrated that, taking 2017 as the base year, the average annual decrease in PM2.5 concentration in sector-wide collaborative, energy priority, and industrial priority emission reduction was 6.7-21.1, 3.1-12.0, and 3.4-14.3 µg·m-3, respectively. Sector-wide collaborative emission reduction had the most notable improvement in PM2.5 pollution. Under the condition of the sector-wide collaborative emission reduction of 40%, the average annual PM2.5 concentration of all cities, excluding Xuzhou and Suqian, met the national Ⅱ standard (35 µg·m-3). The change responses of PM10, SO2, NO2, and CO were similar to that of PM2.5, but O3 pollution increased under the conditions of energy and industrial priorities.

19.
Therap Adv Gastroenterol ; 16: 17562848231170941, 2023.
Article in English | MEDLINE | ID: mdl-37168402

ABSTRACT

Helicobacter pylori infection is an important issue worldwide, and several guidelines have been published for clinicians to achieve successful eradication. However, there are still some patients who remain infected with H. pylori after treatment. Clinicians should identify the reasons that caused treatment failure and find strategies to manage them. We have searched and organized the literature and developed methods to overcome factors that contribute to prior treatment failure, such as poor compliance, inadequate intragastric acid suppression, and antibiotic resistance. To improve compliance, telemedicine or smartphone applications might play a role in the modern world by increasing doctor-patient relationships, while concomitant probiotics could be administered to reduce adverse effects and enhance adherence. For better acid suppression, high-potency and high-dose proton-pump inhibitors or potassium-competitive acid blockers have preferable efficacy. To overcome antibiotic resistance, susceptibility tests either by culture or by genotyping are the most commonly used methods and have been suggested for antibiotic selection before rescue therapy, but empirical therapy according to detailed medical history could be an alternative. Eradication with a longer treatment period (14 days) has a better outcome than shorter period (7 or 10 days). Ultimately, clinicians should select antibiotics based on the patient's history of drug allergy, previous antibiotic exposure, local antibiotic resistance, available medications, and cost. In addition, identifying patients with a high risk of cancer and shared decision-making are also essential for those who have experienced eradication failure.

20.
Med Biol Eng Comput ; 60(2): 487-500, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35015271

ABSTRACT

An important step in brain image analysis is to divide specific brain regions by matching brain slices to standard brain reference atlases, and perform statistical analysis on the labeled neurons in each brain region. Taking mouse fluorescently labeled brain slices as an example, due to the noise and distortion introduced during the preparation of brain slices, and the modal differences with standard brain atlas, the brain slices cannot directly establish an accurate one-to-one correspondence with the brain atlas, which in turn affects the accuracy of the number of labeled neurons in each brain region. This paper introduces the idea of image representation, uses neural networks to realize the registration of different modal mouse brain slices and brain atlas, completes the regional localization of the brain slices, and uses threshold segmentation to detect and count the labeled neurons in each brain region. The method proposed in this paper can effectively solve the problem of large deviation of neurons count caused by the inaccurate division of brain regions in large deformed brain slices, and can automatically realize accurate count of labeled neurons in each brain region of brain slices. The whole framework of method for counting labeled neurons in mouse brain regions based on image representation and registration.


Subject(s)
Brain , Image Processing, Computer-Assisted , Animals , Brain/diagnostic imaging , Head , Magnetic Resonance Imaging , Mice , Neural Networks, Computer , Neurons
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