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1.
J Cell Sci ; 137(6)2024 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-38372383

RESUMEN

Male meiotic division exhibits two consecutive chromosome separation events without apparent pausing. Several studies have shown that spermatocyte divisions are not stringently regulated as in mitotic cells. In this study, we investigated the role of the canonical spindle assembly (SAC) pathway in Caenorhabditis elegans spermatogenesis. We found the intensity of chromosome-associated outer kinetochore protein BUB-1 and SAC effector MDF-1 oscillates between the two divisions. However, the SAC target securin is degraded during the first division and remains undetectable for the second division. Inhibition of proteasome-dependent protein degradation did not affect the progression of the second division but stopped the first division at metaphase. Perturbation of spindle integrity did not affect the duration of meiosis II, and only slightly lengthened meiosis I. Our results demonstrate that male meiosis II is independent of SAC regulation, and male meiosis I exhibits only weak checkpoint response.


Asunto(s)
Caenorhabditis elegans , Huso Acromático , Animales , Masculino , Caenorhabditis elegans/metabolismo , Huso Acromático/metabolismo , Espermatocitos/metabolismo , Meiosis , Cinetocoros/metabolismo , Segregación Cromosómica , Espermatogénesis , Oocitos/metabolismo , Proteínas de Ciclo Celular/metabolismo
2.
Nucleic Acids Res ; 51(16): 8623-8642, 2023 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-37449409

RESUMEN

Corynebacterium glutamicum is an important industrial workhorse for production of amino acids and chemicals. Although recently developed genome editing technologies have advanced the rational genetic engineering of C. glutamicum, continuous genome evolution based on genetic mutators is still unavailable. To address this issue, the DNA replication and repair machinery of C. glutamicum was targeted in this study. DnaQ, the homolog of ϵ subunit of DNA polymerase III responsible for proofreading in Escherichia coli, was proven irrelevant to DNA replication fidelity in C. glutamicum. However, the histidinol phosphatase (PHP) domain of DnaE1, the α subunit of DNA polymerase III, was characterized as the key proofreading element and certain variants with PHP mutations allowed elevated spontaneous mutagenesis. Repression of the NucS-mediated post-replicative mismatch repair pathway or overexpression of newly screened NucS variants also impaired the DNA replication fidelity. Simultaneous interference with the DNA replication and repair machinery generated a binary genetic mutator capable of increasing the mutation rate by up to 2352-fold. The mutators facilitated rapid evolutionary engineering of C. glutamicum to acquire stress tolerance and protein overproduction phenotypes. This study provides efficient tools for evolutionary engineering of C. glutamicum and could inspire the development of mutagenesis strategy for other microbial hosts.


Asunto(s)
Corynebacterium glutamicum , ADN Polimerasa III , ADN Polimerasa III/genética , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Replicación del ADN/genética , Mutación , Tasa de Mutación , Ingeniería Metabólica
3.
Small ; : e2407706, 2024 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-39397255

RESUMEN

Solution-processing is the primary method for fabricating high-efficiency perovskite solar cells (PSCs), where solvent choice critically influences film formation and quality. Although additives can optimize film formation dynamics by balancing nucleation and growth of perovskite, they can also induce heterogeneous nucleation due to competitive coordination and varying crystallization kinetics, leading to compositional heterogeneity and structural disorders. Herein, a perovskite precursor solution is developed using acetonitrile (ACN) as a weak coordination host solvent instead of the traditional N,N-dimethylformamide (DMF). The ACN-based perovskite precursor solution reduces heterogeneous nucleation typically caused by the competitive coordination effect of DMF, and cuts costs by half compared to DMF-based precursor solutions. This approach promotes a single crystallization pathway via a dimethyl sulfoxide-solvated intermediate phase to α-FAPbI3, which extends the anti-solvent operation window, and enhances the crystallinity of perovskite films, and reduces defect states. The power conversion efficiencies (PCE) of 23.62% and 20.13% is achieved for the PSC and minimodule, respectively. The PSC retains over 97% of its initial efficiency after 800 h of continuous illumination under maximum power point tracking (MPPT). These findings provide valuable insights into solvent interactions in perovskite film formation and offer a cost-effective strategy for improving the device's performance and stability.

4.
BMC Pulm Med ; 24(1): 46, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38254043

RESUMEN

OBJECTIVE: To investigate the effect of interferon-γ (IFN-γ) on the immune microenvironment and the polarity of tumor-associated macrophages (TAMs) in stage IA non-small cell lung cancer (NSCLC) and its mechanisms. METHODS: Human non-small cell lung cancer A549 cells were treated with a series of IFN-γ concentrations (0, 50, 100, 150, 200, 250, and 300 ng/mL). Tumor tissues from patients with stage IA NSCLC were cultured using the air-liquid interface culture technique to establish a tumor microenvironment (TME) organ model. The NSCLC model was constructed by subcutaneously embedding small tumor pieces into the back of nonobese diabetic severe combined immune deficiency (NOD SCID) mice. The size and weight of the tumors were recorded, and the tumor volume was calculated. CCK-8 assays were used to investigate cell proliferation, flow cytometry and TUNEL staining were used to evaluate cell apoptosis, colony formation was investigated by cloning experiments, and cell invasion and migration were evaluated by Transwell assays and scratch tests. The expression of apoptosis-related proteins (Bax, Bcl-2 and C-caspase 3), M2 polarization-related markers (CD163, CD206 and IDO1), and marker proteins of cytotoxic T cells and helper T cells (CD8 and CD4) was detected by Western blot. The expression of Ki-67 and IDO1 was detected by immunohistochemistry, and the levels of IL-6, IL-10, IL-13 and TNF-α were measured by ELISA. The expression of CD68 was measured by RT‒qPCR, and the phagocytosis of TAMs was evaluated by a Cell Trace CFSE kit and cell probe staining. RESULTS: The proliferation activity of A549 cells increased with increasing IFN-γ concentration and peaked when the concentration reached 200 ng/mL, and the proliferation activity of A549 cells was suppressed thereafter. After treatment with 200 ng/mL IFN-γ, the apoptosis rate of cells decreased, the number of cell colonies increased, the invasion and migration of cells were promoted, the expression of Bax and C-caspase 3 was downregulated, and the expression of Bcl-2 was upregulated in cells and the TME model. In the TME model, CD163, CD206, IDO1 and Ki-67 were upregulated, CD8 and CD4 were downregulated, apoptosis was reduced, the levels of IL-6 and TNF-α were decreased, and the levels of IL-10 and IL-13 were increased. IL-4 induced TAMs to express CD163 and CD206, reduced the levels of IL-6 and TNF-α, increased the levels of IL-10 and IL-13, and weakened the phagocytic function of TAMs. IFN-γ treatment further enhanced the effect of IL-4 and enhanced the viability of A549 cells. IDO1 decreased the viability of T cells and NK cells, while suppressing the effect of IFN-γ. In mice, compared with NSCLC mice, the tumor volume and weight of the IFN-γ group were increased, the expression of CD163, CD206, IDO1, Ki-67 and Bcl-2 in tumor tissue was upregulated, the expression of Bax and C-caspase 3 was downregulated, and apoptosis was reduced. The levels of IL-6 and TNF-α were decreased, and the levels of IL-10 and IL-13 were increased in the serum of mice. CONCLUSION: In stage IA NSCLC, a low concentration of IFN-γ promotes the polarization of TAMs to the M2 phenotype in the TME model by upregulating the expression of IDO1, promoting the viability of cancer cells, inhibiting the viability of T cells and NK cells, and thus establishing an immune microenvironment conducive to tumor progression.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Interferón gamma , Neoplasias Pulmonares , Microambiente Tumoral , Animales , Humanos , Ratones , Proteína X Asociada a bcl-2 , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Caspasa 3 , Interferón gamma/farmacología , Interleucina-10 , Interleucina-13 , Interleucina-4 , Interleucina-6 , Antígeno Ki-67 , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/metabolismo , Ratones SCID , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/inmunología , Factor de Necrosis Tumoral alfa
5.
Sensors (Basel) ; 24(19)2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39409539

RESUMEN

The rotational speed vectors of the bearing balls affect their service life and running performance. Observing the actual rotational speed of the ball is a prerequisite for revealing its true motion law and conducting sliding behavior simulation analysis. To address the need for accuracy and real-time measurement of spin angular velocity, which is also under high-frequency and high-speed ball motion conditions, a new measurement method of ball rotation vectors based on a binocular vision system is proposed. Firstly, marker points are laid on the balls, and their three-dimensional (3D) coordinates in the camera coordinate system are calculated in real time using the triangulation principle. Secondly, based on the 3D coordinates before and after the movement of the marker point and the trajectory of the ball, the mathematical model of the spin motion of the ball was established. Finally, based on the ball spin motion model, the three-dimensional vision measurement technology was first applied to the measurement of the bearing ball rotation vector through formula derivation, achieving the analysis of bearing ball rolling and sliding characteristics. Experimental results demonstrate that the visual measurement system with the frame rate of 100 FPS (frames per second) yields a measurement error within ±0.2% over a speed range from 5 to 50 RPM (revolutions per minute), and the maximum measurement errors of spin angular velocity and linear velocity are 0.25 °/s and 0.028 mm/s, respectively. The experimental results show that this method has good accuracy and stability in measuring the rotation vector of the ball, providing a reference for bearing balls' rotational speed monitoring and the analysis of the sliding behavior of bearing balls.

6.
Small ; 19(35): e2301061, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37104854

RESUMEN

The additive engineering strategy promotes the efficiency of solution-processed perovskite solar cells (PSCs) over 25%. However, compositional heterogeneity and structural disorders occur in perovskite films with the addition of specific additives, making it imperative to understand the detrimental impact of additives on film quality and device performance. In this work, the double-edged sword effects of the methylammonium chloride (MACl) additive on the properties of methylammonium lead mixed-halide perovskite (MAPbI3-x Clx ) films and PSCs are demonstrated. MAPbI3-x Clx films suffer from undesirable morphology transition during annealing, and its impacts on the film quality including morphology, optical properties, structure, and defect evolution are systematically investigated, as well as the power conversion efficiency (PCE) evolution for related PSCs. The FAX (FA = formamidinium, X = I, Br, and Ac) post-treatment strategy is developed to inhibit the morphology transition and suppress defects by compensating for the loss of the organic components, a champion PCE of 21.49% with an impressive open-circuit voltage of 1.17 V is obtained, and remains over 95% of the initial efficiency after storing over 1200 hours. This study elucidates that understanding the additive-induced detrimental effects in halide perovskites is critical to achieve the efficient and stable PSCs.

7.
Langmuir ; 39(35): 12365-12383, 2023 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-37611147

RESUMEN

It is crucial to comprehend how the oil film varies under dynamic operating conditions and the accompanying friction properties to better grasp the friction mechanism and control friction behavior. To model the friction characteristics under boundary lubrication (BL) and elastohydrodynamic lubrication (EHL), nonequilibrium molecular dynamics simulations with various numbers of hexadecane molecules as lubricating oil were conducted in this research under the conditions of dynamic speed and dynamic load. All the dynamic operating conditions have the form of sine waves, with various frequencies and amplitudes. According to the findings, the friction force is strongly connected with interfaces where relative sliding takes place, whose number, velocity difference, and the degree of solidification have significant influences. The variation of amplitude under dynamic load can cause a regular change in the density of the lubricating layer, while the variation of frequency can cause a change in molecular layer's range of motion. Both effects are crucial for friction. The structure of the lubricating layer with lower friction varies with various frequencies for dynamic velocity. Both high and small amplitudes of velocity offer advantages to form a stable film structure at low frequencies in the BL and EHL regions, while the amplitude in the BL area has minimal association with friction at high frequencies. At high frequencies in the EHL region, the friction rises as the amplitude of velocity grows and the lubricating layer becomes more unstable.

8.
Environ Sci Technol ; 57(9): 3516-3526, 2023 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-36802547

RESUMEN

Soil emissions have long been recognized as an important source of nitric oxide (NO), which regulates atmospheric oxidative capacity and the production of air pollutants. Recent research has also indicated that nitrous acid (HONO) can be emitted in significant quantities from soil microbial activities. However, only a few studies have quantified emissions of HONO along with NO from a wide range of soil types. In this study, we measured emissions of HONO and NO from soil samples collected from 48 sites across China and found much higher emissions of HONO than of NO, especially for samples from northern China. We performed a meta-analysis of 52 field studies in China, which revealed that long-term fertilization increased the abundance of nitrite-producing genes much more than the abundance of NO-producing genes. This promotion effect was greater in northern China than in southern China. In simulations using a chemistry transport model with laboratory-derived parametrization, we found that HONO emissions had a greater effect than NO emissions on air quality. Moreover, we determined that with projected continuous reductions in anthropogenic emissions, the contribution from soils to maximum 1 h concentrations of hydroxyl radicals and ozone and daily average concentrations of particulate nitrate in the Northeast Plain will increase to 17%, 4.6%, and 14%, respectively. Our findings highlight the need to consider HONO in the assessment of the loss of reactive oxidized nitrogen from soils to the atmosphere and its effect on air quality.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Ácido Nitroso/análisis , Suelo , Nitrógeno/análisis , Nitritos/análisis , Contaminación del Aire/análisis , Contaminantes Atmosféricos/análisis , Óxido Nítrico/análisis
9.
Environ Sci Technol ; 57(20): 7764-7776, 2023 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-37155674

RESUMEN

Oxygenated organic molecules (OOMs) are critical intermediates linking volatile organic compound oxidation and secondary organic aerosol (SOA) formation. Yet, the understanding of OOM components, formation mechanism, and impacts are still limited, especially for urbanized regions with a cocktail of anthropogenic emissions. Herein, ambient measurements of OOMs were conducted at a regional background site in South China in 2018. The molecular characteristics of OOMs revealed dominant nitrogen-containing products, and the influences of different factors on OOM composition and oxidation state were elucidated. Positive matrix factorization analysis resolved the complex OOM species to factors featured with fingerprint species from different oxidation pathways. A new method was developed to identify the key functional groups of OOMs, which successfully classified the majority species into carbonyls (8%), hydroperoxides (7%), nitrates (17%), peroxyl nitrates (10%), dinitrates (13%), aromatic ring-retaining species (6%), and terpenes (7%). The volatility estimation of OOMs was improved based on their identified functional groups and was used to simulate the aerosol growth process contributed by the condensation of those low-volatile OOMs. The results demonstrate the predominant role of OOMs in contributing sub-100 nm particle growth and SOA formation and highlight the importance of dinitrates and anthropogenic products from multistep oxidation.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Atmosféricos/análisis , Hong Kong , Nitratos , Terpenos , Aerosoles/análisis
10.
Nano Lett ; 22(22): 8835-8844, 2022 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-36375092

RESUMEN

Although keratins are robust in nature, hydrogels producing their extracts exhibit poor mechanical properties due to the complicated composition and ineffective self-assembly. Here we report a bioinspired strategy to fabricate robust keratin hydrogels based on mechanism study through recombinant proteins. Homotypic and heterotypic self-assembly of selected type I and type II keratins in different combinations was conducted to identify crucial domain structures for the process, their kinetics, and relationship with the mechanical strength of hydrogels. Segments with best performance were isolated and used to construct novel assembling units. The new design outperformed combinations of native proteins in mechanical properties and in biomedical applications such as controlled drug release and skin regeneration. Our approach not only elucidated the critical structural domains and underlying mechanisms for keratin self-assembly but also opens an avenue toward the rational design of robust keratin hydrogels for biomedical applications.


Asunto(s)
Hidrogeles , Queratinas , Hidrogeles/química , Queratinas/química , Queratinas/farmacología , Piel , Liberación de Fármacos
11.
Langmuir ; 38(2): 801-809, 2022 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-34951309

RESUMEN

Surface-enhanced Raman scattering (SERS) has been a useful sensing technique, in which inelastic light scattering can be significantly enhanced by absorbing molecules onto rough metal surfaces or nanoparticles. Although many methods have been developed to prepare SERS substrates, it is still highly desirable and challenging to design SERS substrates, especially with highly ordered and controlled three-dimensional (3D) structures. In this work, we develop novel SERS substrates with regular volcano-shaped polymer structures using the versatile solvent on-film annealing method. Polystyrene (PS) nanospheres are first synthesized by surfactant-free emulsion polymerization and assembled on poly(methyl methacrylate) (PMMA) films. After annealing in acetic acid vapors, PMMA chains are selectively swollen and wet the surfaces of the PS nanospheres. By selectively removing the PS nanospheres using cyclohexane, volcano-shaped PMMA films can be obtained. Compared with flat PMMA films with water contact angles of ∼74°, volcano-shaped PMMA films exhibit higher water contact angles of ∼110° due to the sharp features and rough surfaces. The volcano-shaped PMMA films are then coated with gold nanoparticles (AuNPs) as SERS substrates. Using rhodamine 6G as the probe molecules, the SERS results show that the Raman signals of the volcano-shaped PMMA/AuNP hybrid substrates are much higher than those of the pristine PMMA films and PMMA films with AuNPs. For the volcano-shaped PMMA/AuNP hybrid substrates using 400 nm PS nanospheres, a high enhancement factor (EF) value of ∼1.12 × 105 with a detection limit of 10-8 M is obtained in a short integration time of 1 s. A linear calibration line with an R2 value of 0.918 is also established, demonstrating the ability to determine the concentrations of the analytes. This work offers significant insight into developing novel SERS substrates, which is crucial for improving the detection limits of analytes.

12.
J Org Chem ; 87(22): 15547-15558, 2022 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-36306342

RESUMEN

Pyrano[4,3-c]pyridine-diones, which are the key skeleton of bioactive compounds and functional materials, are usually prepared via a multistep synthesis using expensive substrates. This work demonstrates that Rh(III)-catalyzed dual C(sp2)-H functionalization and C-O/C-N annulation of monoamide fumarates can produce pyrano[4,3-c]pyridine-1,5(6H)-diones in high yield (up to 82%) in a single step. The substrates of monoamide fumarates and acetylenes are structurally simple, readily available, and inexpensive. The additive AgSbF6 effectively raised the yields. On account of easier dehydrogenation of OH in the COOH group than NH in the amide group in the reaction, the process first undergoes C-O annulation and then is succeeded by C-N annulation.


Asunto(s)
Rodio , Rodio/química , Estructura Molecular , Catálisis , Fumaratos , Piridinas/química
13.
Environ Sci Technol ; 56(7): 4173-4186, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-35287433

RESUMEN

This study reports molecular-level characterization of brown carbon (BrC) attributed to water-soluble organic carbon in six snowpack samples collected from northern Xinjiang, China. The molecular composition and light-absorbing properties of BrC chromophores were unraveled by application of high-performance liquid chromatography (HPLC) coupled to a photodiode array (PDA) detector and high-resolution mass spectrometry. The chromophores were classified into five major types, that is, (1) phenolic/lignin-derivedcompounds, (2) flavonoids, (3) nitroaromatics, (4) oxygenated aromatics, and (5) other chromophores. Identified chromophores account for ∼23-64% of the total light absorption measured by the PDA detector in the wavelength range of 300-370 nm. In the representative samples from urban and remote areas, oxygenated aromatics and nitroaromatics dominate the absorption in the wavelengths below and above 320 nm, respectively. The highly polluted urban sample shows the most complex HPLC-PDA chromatogram, and more other chromophores contribute to the bulk absorption. Phenolic/lignin-derived compounds are the most light-absorbing species in the soil-influenced sample. Chromophores in two remote samples exhibit ultraviolet-visible features distinct from other samples, which are attributed to flavonoids. Identification of individual chromophores and quantitative analysis of their optical properties are helpful for elucidating the roles of BrC in snow radiative balance and photochemistry.


Asunto(s)
Carbono , Agua , Aerosoles/análisis , Carbono/análisis , China , Monitoreo del Ambiente , Espectrometría de Masas , Agua/química
14.
Environ Sci Technol ; 56(11): 6933-6943, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-34732048

RESUMEN

Nitro-phenolic compounds (NPs) have attracted increasing attention because of their health risks and impacts on visibility, climate, and atmospheric chemistry. Despite many measurements of particulate NPs, the knowledge of their gaseous abundances, sources, atmospheric fates, and impacts remains incomplete. Here, 18 gaseous NPs were continuously measured with a time-of-flight chemical ionization mass spectrometer at a background site in South China in autumn and winter. Abundant NPs were observed in the continental outflows from East Asia, with a total concentration up to 122.1 pptv. Secondary formation from the transported aromatics dominated the observed NPs, with mono-NPs exhibiting photochemical daytime peaks and nighttime enrichments of di-NPs and Cl-substituted NPs. The budget analysis indicates that besides the •OH oxidation of aromatics, the NO3• oxidation also contributed significantly to the daytime mono-NPs, while the further oxidation of mono-NPs by NO3• dominated the nocturnal formation of di-NPs. Photolysis was the main daytime sink of NPs and produced substantial HONO, which would influence atmospheric oxidation capacity in downwind and background regions. This study provides quantitative insights on the formation and impacts of gaseous NPs in the continental outflow and highlights the role of NO3• chemistry in the secondary nitro-aromatics production that may facilitate regional pollution.


Asunto(s)
Gases , Nitrocompuestos , China , Polvo , Estaciones del Año
15.
Environ Res ; 208: 112670, 2022 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-35021066

RESUMEN

Previous studies have indicated that black carbon (BC) potentially induces snow albedo reductions across northern China. However, the effects of other light-absorbing particles (LAPs, e.g., mineral dust, MD), snow grain shape, or BC-snow mixing state on snow albedo have been largely ignored. Here we evaluate the BC- and MD-induced snow albedo reductions and radiative forcings (RFs) using an updated Snow, Ice, and Aerosol Radiation radiative transfer model, considering all of the potential factors that can be derived from the field observations across northern China. The results highlight that the LAP-induced albedo reductions for nonspherical snow grains are 2%-30% less than those for spherical grains. Furthermore, BC-snow internal mixing can significantly enhance albedo reduction by a factor of 1.42-1.48 relative to external mixing, with snow grain radius ranging from 100 to 1000 µm. The mean regional BC + MD-induced snow albedo reductions are amplified by the increase of snow grain radius, ranging from 0.012 to 0.123 for fresh snow to 0.016-0.227 for old snow. Finally, we discuss the relative contributions of BC and MD to the albedo reductions and RFs, highlighting the dominant role of BC in reducing snow albedo across northern China.


Asunto(s)
Monitoreo del Ambiente , Nieve , Carbono/análisis , China , Polvo/análisis , Minerales
16.
BMC Med Imaging ; 22(1): 65, 2022 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-35392835

RESUMEN

BACKGROUND: Ultrasound (US) guided transoral biopsy is a novel and safe procedure for obtaining tissue in patients with oral masses. However, this procedure is less commonly used in comparison to US guided transcutaneous biopsy. The aim of this study is to compare the efficacy and safety of US-guided transoral and transcutaneous core needle biopsy (CNB) in patients with oral masses. METHODS: From November 2019 to March 2021, consecutive patients with oral masses were randomly assigned to undergo US-guided transoral CNB (transoral group) and US-guided transcutaneous CNB from a submental approach (transcutaneous group). During the operation, procedure time, intra­operative blood loss volume, diagnostic performance, rate of complications and pain level were recorded and compared. RESULTS: There were 112 patients (62 in the transoral group and 50 in the transcutaneous group) evaluated in this study. The postprocedural complication rate of the transcutaneous group was significantly higher than the transoral group (24% vs. 0%, P = 0.000). There was no significant difference in accuracy (95.2% vs. 88%, P = 0.30), biopsy time (76 ± 12 s vs. 80 ± 13 s, p = 0.09), blood losses (2.6 ± 0.5 mL vs. 2.7 ± 0.4 mL, p = 0.17) and visual analogue score (p = 0.327 and p = 0.444 before and after the sampling procedure) between the two groups. CONCLUSION: US-guided transoral CNB results in high rates of technical success and lower rates of postprocedural complications.


Asunto(s)
Biopsia Guiada por Imagen , Ultrasonografía Intervencional , Biopsia con Aguja Gruesa/efectos adversos , Biopsia con Aguja Gruesa/métodos , Humanos , Biopsia Guiada por Imagen/efectos adversos , Biopsia Guiada por Imagen/métodos , Estudios Retrospectivos , Ultrasonografía , Ultrasonografía Intervencional/métodos
17.
J Environ Sci (China) ; 114: 53-65, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35459514

RESUMEN

The Asian Tropopause Aerosols Layer (ATAL) refers to an accumulation of aerosols in the upper troposphere and lower stratosphere during boreal summer over Asia, which has a fundamental impact on the monsoon system and climate change. In this study, we primarily analyze the seasonal to sub-seasonal variations of the ATAL and the factors potentially influencing those variations based on MERRA2 reanalysis. The ability of the reanalysis to reproduce the ATAL is well validated by CALIPSO observations from May to October 2016. The results reveal that the ATAL has a synchronous spatiotemporal pattern with the development and movement of the Asian Summer Monsoon. Significant enhancement of ATAL intensity is found during the prevailing monsoon period of July-August, with two maxima centered over South Asia and the Arabian Peninsula. Owing to the fluctuations of deep convection, the ATAL shows an episodic variation on a timescale of 7-12 days. Attribution analysis indicates that deep convection dominates the variability of the ATAL with a contribution of 62.7%, followed by a contribution of 36.6% from surface pollutants. The impact of precipitation is limited. The ATAL further shows a clear diurnal variation: the peak of ATAL intensity occurs from 17:30 to 23:30 local time (LT), when the deep convection becomes strongest; the minimum ATAL intensity occurs around 8:30 LT owing to the weakened deep convection and photochemical reactions in clouds. The aerosol components of the ATAL show different spatiotemporal patterns and imply that black carbon and organic carbon come mainly from India, whereas sulfate comes mainly from China during the prevailing monsoon period.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Ambientales , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Carbono/análisis , Convección , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Estaciones del Año
18.
Int J Hyperthermia ; 38(1): 479-487, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33730965

RESUMEN

OBJECTIVE: To evaluate the safety and efficacy of ultrasound (US)-guided percutaneous microwave ablation (UgPMWA) for palliative treatment of advanced head and neck malignancies. MATERIALS AND METHODS: This study includes 18 consecutive patients with advanced head and neck malignancies (n = 24), who have undergone UgPMWA for palliative treatment at our institution from December 2016 to April 2020. The maximum diameter and volume of the tumor were assessed by US, CT or MRI before microwave ablation (MWA), 1, 3 and 6 months after MWA and every 6 months thereafter. The quality of life was clinically assessed by the University of Washington Head and Neck Quality of Life questionnaire (UW-QOl). RESULTS: The success rate of tumor-targeting microwave antenna placement was 100%. No nerve injury and serious complications or death occurred during the perioperative period. The follow-up duration varied from 1 month to 38 months (11.56 ± 10.23 months) among patients. By the last follow-up before submission, the value of maximum diameter (5.00 ± 2.90 vs 3.28 ± 2.11 cm. p < 0.05) and tumor volume decreased significantly(74.35 ± 46.88 vs 47.45 ± 24.08 cm3. p < 0.05)respectively after palliative treatment with UgPMWA. UW-QOl of the patients was improved (59.24 ± 11.51 vs 69.84 ± 8.12, p < 0.05). CONCLUSION: UgPMWA is safe and effective for the palliative treatment of head and neck malignancies. Ultrasonic guidance can indicate an accurate location of the microwave antenna. It can also monitor the ablation area in real-time during the operation to avoid damage to surrounding normal tissues.


Asunto(s)
Ablación por Catéter , Neoplasias de Cabeza y Cuello , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Microondas/uso terapéutico , Cuidados Paliativos , Calidad de Vida , Resultado del Tratamiento , Ultrasonografía Intervencional
19.
Nanotechnology ; 31(37): 375605, 2020 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-32454465

RESUMEN

In this paper, an effective approach is demonstrated for the fabrication of IrO2-decorated polystyrene@functionalized polypyrrole (core@shell; PS@PPyNH2) microspheres. The synthesis begins with the preparation of monodispersive PS microspheres with a diameter of 490 nm, by a process of emulsifier-free emulsion polymerization, followed by a copolymerization process involving pyrrole and PyNH2 monomers in a PS microsphere aqueous suspension, to produce uniform PS@PPyNH2 microspheres with a diameter of 536 nm. The loading of 2 nm IrO2 nanoparticles onto the PS@PPyNH2 microspheres can be easily adjusted by tuning the pH value of the IrO2 colloidal solution and the PS@PPyNH2 suspension. At pH 4, we successfully obtain IrO2-decorated PS@PPyNH2 microspheres via electrostatic attraction and hydrogen bonding simultaneously between the negatively-charged IrO2 nanoparticles and the positively-charged PS@PPyNH2 microspheres. These IrO2-decorated PS@PPyNH2 microspheres exhibit a characteristic cyclic voltammetric profile, similar to that of an IrO2 thin film. The charge storage capacity is 5.19 mA cm-2, a value almost five times greater than that of PS@PPyNH2 microspheres. In addition, these IrO2-decorated PS@PPyNH2 microspheres exhibit excellent cell viability and biocompatibility.

20.
Sensors (Basel) ; 20(21)2020 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-33114022

RESUMEN

The imagery of airborne highly squinted synthetic aperture radar (SAR) with curved trajectory is a challenging task due to the translational-variant range cell migration (RCM) and azimuth modulation. However, in most cases of practical application, the curved trajectory cannot be accurately known, which brings greater difficulties to the imaging problem. To accommodate these issues, we propose a novel motion modelling and optimisation based imaging algorithm for the highly squinted SAR with unknown curved trajectory. First, to correct the translational-variant RCM, a coarse-to-fine RCM correction scheme as well as a range perturbation approach is applied. Afterwards, an optimisation model of motion information under the criterion of minimum entropy is built during the azimuth processing by nonlinear chirp scaling (NLCS). Correspondingly, a differential evolution (DE) optimisation strategy is proposed to estimate the motion information in an iterative manner. We empirically compare the proposed algorithms with several state-of-the-art highly squinted curved SAR imaging algorithms. Numerical results show the effectiveness of the proposed method in the case without any prior information of the curved trajectory.

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