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1.
Environ Geochem Health ; 46(5): 147, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38578456

RESUMEN

The Qinghai-Tibet Plateau, located at the Third Pole and known as the "Asian water tower," serves as a crucial ecological barrier for China. Grasping the soil quality on the Qinghai-Tibet Plateau holds paramount importance for the rational and scientific exploitation of soil resources within the region and is essential for vegetation restoration and ecological reconstruction. This study, conducted in Maqin County, Qinghai Province, collected 1647 soil samples (0-20 cm) within a study area of 6300 km2. Sixteen soil indicators were selected that were split into beneficial (N, P, S, and B), harmful (Cr, Hg, As, Pb, Ni, and Cd), and essential (Cu, Zn, Se, Ga, K, and Ca) elements. The Soil Quality Index (SQI) was computed to assess soil quality across diverse geological contexts, land cover classifications, and soil profiles. The results indicate that the overall SQI in the study area was comparatively high, with most regions having an SQI between 0.4 and 0.6, categorized as moderately to highly satisfactory. Among the different geological backgrounds, the highest SQI was found in the Quaternary alluvium (0.555) and the lowest in the Precambrian Jinshuikou Formation (0.481). Regarding different land-use types, the highest SQI was observed in glacier- and snow-covered areas (0.582) and the lowest in other types of grassland (0.461). The highest SQI was recorded in typical alpine meadow soil (0.521) and the lowest in leached brown soil (0.460). The evaluation results have significant reference value for the sustainable utilization and management of soil in Maqin County, Qinghai Province, China.


Asunto(s)
Mercurio , Suelo , Humanos , Tibet , China , Actividades Humanas
2.
Materials (Basel) ; 17(4)2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38399063

RESUMEN

Concrete surface cracks serve as early indicators of potential structural threats. Visual inspection, a commonly used and versatile concrete condition assessment technique, is employed to assess concrete degradation by observing signs of damage on the surface level. However, the method tends to be qualitative and needs to be more comprehensive in providing accurate information regarding the extent of damage and its evolution, notwithstanding its time-consuming and environment-sensitive nature. As such, the integration of image analysis techniques with artificial intelligence (AI) has been increasingly proven efficient as a tool to capture damage signs on concrete surfaces. However, to improve the performance of automated crack detection, it is imperative to intensively train a machine learning model, and questions remain regarding the required image quality and image collection methodology needed to ensure the model's accuracy and reliability in damage quantitative analysis. This study aims to establish a procedure for image acquisition and processing through the application of an image-based measurement approach to explore the capabilities of concrete surface damage diagnosis. Digitizing crack intensity measurements were found to be feasible; however, larger datasets are required. Due to the anisotropic behavior of the damage, the model's ability to capture crack directionality was developed, presenting no statistically significant differences between the observed and predicted values used in this study with correlation coefficients of 0.79 and 0.82.

3.
Environ Monit Assess ; 195(12): 1422, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37932466

RESUMEN

The Qinghai-Tibet Plateau stands as the loftiest geographical area on our planet, frequently denoted as the "Crown of the Globe." To acquire an exhaustive comprehension of the heavy metal contamination situation in the topsoil of Maqin County, Qinghai Province, a total of 1616 surface soil specimens were gathered across a 6300 km2 area. An examination was carried out on 12 metallic elements to investigate the impact of diverse geological contexts, soil categorizations, and land utilization practices on the levels of heavy metals. Additionally, the fundamental factors contributing to these trends were probed. The findings unveiled that the mean levels of the 12 metallic elements in the topsoil of Maqin County surpassed or equaled the baseline values of soil heavy metal concentrations within the research region. The coefficients of variation (CV) values for Hg, Sb, Ni, and Pb exceeded 30%, with Hg showing strong variation. The overall pollution level in the study area was classified as mild, posing a moderate ecological risk. In this study, we performed a multi-factor analysis of the significant differences in heavy metal concentrations among different geological backgrounds, soil types, and land-use types. The results showed that geological background had extremely significant impacts on elements such as Ba, Be, Cd, Cr, Cu, Hg, Ni, Sb, Tl, and Zn (p < 0.01). Soil type had an extremely significant influence on Be, Cd, Cu, and Zn (p < 0.01), as well as a significant influence on Ba (p < 0.05). Land-use type had an extremely significant impact on Ba (p < 0.01) and a significant impact on Cd (p < 0.05). Building upon the amalgamation of the outcomes from the Pearson correlation analysis, it was inferred that the main source of heavy metals in Maqin County, Qinghai Province, was the geological background.


Asunto(s)
Mercurio , Metales Pesados , Contaminantes del Suelo , Cadmio/análisis , Contaminantes del Suelo/análisis , Monitoreo del Ambiente/métodos , Medición de Riesgo , China , Metales Pesados/análisis , Suelo , Mercurio/análisis , Contaminación Ambiental/análisis
4.
Life (Basel) ; 13(4)2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37109467

RESUMEN

(1) Background: There is growing interest in using insects to treat nutrient-rich organic wastes, such as the black soldier fly (BSF), one of the most efficient organic waste recyclers for upcycling nutrients into the food system. Although biochar (BC) was shown to enhance nutrient retention and the final product quality during the composting of livestock and poultry manure in many previous studies, little information is available on the effect of BC on livestock manure bioconversion by black soldier fly larvae (BSFL). (2) Methods: This study investigated the effect of adding a small amount of BC to chicken manure (CM) on the bioconversion system of the black soldier fly (including N2O and NH3 emissions and the final distribution of nitrogen during the treatment process). (3) Results: The lowest N2O and NH3 emission and highest residual nitrogen in the substrate were observed in the 15% BC treatment. The highest bioconversion rate of CM (8.31%) and the peak of larval biomass was obtained in the 5% BC treatment. (4) Conclusions: The results demonstrate the feasibility of adding 5% BC to reduce pollution and achieve a satisfactory BSFL-based CM bioconversion efficiency.

5.
Int J Mol Sci ; 24(6)2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36982656

RESUMEN

Groat protein content (GPC) is a key quality trait attribute in oat. Understanding the variation of GPC in oat germplasms and identifying genomic regions associated with GPC are essential for improving this trait. In this study, the GPC of 174 diverse oat accessions was evaluated in three field trials. The results showed a wide variation in GPC, ranging from 6.97% to 22.24% in this panel. Hulless oats displayed a significantly higher GPC compared to hulled oats across all environments. A GWAS analysis was performed based on 38,313 high-quality SNPs, which detected 27 non-redundant QTLs with 41 SNPs significantly associated with GPC. Two QTLs on chromosome 6C (QTL16) and 4D (QTL11) were consistently detected in multiple environments, with QTL16 being the most significant and explaining the highest proportion of the phenotypical variation in all tested environments except in CZ20. Haplotype analysis showed that the favorable haplotypes for GPC are more prevalent in hulless oats. These findings provide a foundation for future efforts to incorporate favorable alleles into new cultivars through introgression, fine mapping, and cloning of promising QTLs.


Asunto(s)
Avena , Estudio de Asociación del Genoma Completo , Avena/genética , Mapeo Cromosómico , Sitios de Carácter Cuantitativo , Fenotipo , Grano Comestible/genética , Polimorfismo de Nucleótido Simple
6.
Life (Basel) ; 13(1)2023 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-36676183

RESUMEN

Aflatoxin B1 (AFB1) is a common mycotoxin contaminant in cereals that causes severe economic losses and serious risks to the health of humans and animals. In this paper, we investigated the characteristics of AFB1 degradation by black soldier fly larvae (BSFL) combined with commensal intestinal microorganisms. Germ-free BSFL and non-sterile BSFL were reared on peanut meal spiked with AFB1 for 10 days. The result showed that germ-free BSFL and non-sterile BSFL could achieve 31.71% and 88.72% AFB1 degradation, respectively, which indicated the important role of larvae gut microbiota in AFB1 degradation. Furthermore, twenty-five AFB1-degrading bacteria were isolated from BSFL gut, and S. acidaminiphila A2 achieved the highest AFB1 degradation, by 94%. When S. acidaminiphila A2 was re-inoculated to BSFL, the detrimental effect of AFB1 on the growth performance of BSFL was alleviated, and complete AFB1 degradation in peanut meal was obtained. In conclusion, the present study may provide a strategy to degrade AFB1 in feedstuff through bioconversion with BSFL in combination with gut-originated AFB1-degrading bacteria, while providing a sustainable insect protein and fat source to animals.

7.
J Int Med Res ; 50(1): 3000605211069485, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34994238

RESUMEN

Poland syndrome is a rare congenital developmental deformity characterized by unilateral agenesis or hypoplasia of thoracic wall soft tissue. We report two adult cases of Poland syndrome detected by computed tomography (CT) images. CT images of the two cases depicted an asymmetric chest wall with the absence of a breast and agenesis of the pectoralis muscles. A physical examination of case 1 showed a thin right chest wall with depression of the right nipple region. Hand deformities were also observed, including brachydactyly and syndactyly. In case 2, hand deformities were not found in a physical examination. Using multi-planar reconstruction, the size, position, origin, and termination of bilateral pectoral muscles could be compared symmetrically. For patients with Poland syndrome, a timely diagnosis and treatment are important. The use of chest CT in clinical practice could play an important role in the early diagnosis and treatment of Poland syndrome.


Asunto(s)
Síndrome de Poland , Pared Torácica , Adulto , Humanos , Pezones , Músculos Pectorales/diagnóstico por imagen , Síndrome de Poland/diagnóstico por imagen , Pared Torácica/diagnóstico por imagen , Tomografía Computarizada por Rayos X
8.
Environ Pollut ; 287: 117625, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34186500

RESUMEN

In recent years, severe air pollution still frequently occurs in winter despite the effective implementation of clean air actions in China. Therefore, field measurements of particle composition and gas precursors were collected from December 1, 2018 to January 15, 2019 at an urban site in a central Chinese city to investigate the existing mechanisms of pollution. The hourly averaged PM2.5 concentration during the campaign was 92.7 µg m-3, with nitrate and organic aerosol (OA) demonstrated as the principal components. Generally, NO2 oxidation in the daytime was observed as the major mechanism for nitrate generation, and aerosol water content (AWC) showed its influential role with the associated increases in the nitrogen oxidation and nitrate partitioning ratios. When AWC increased from dozens to hundreds of µg m-3 after the afternoon, nocturnal N2O5 hydrolysis was demonstrated as the overriding mechanism and provoked extreme contamination of nitrates. Five sources of organic aerosols (OAs) were identified: hydrocarbon-like OAs (HOAs, 16.5%), coal combustion OAs (CCOAs, 19.2%), biomass burning OAs (BBOAs, 9.9%), semi-volatile oxygenated OAs (SV-OOAs, 29.4%), and low-volatile oxygenated OAs (LV-OOAs, 25.0%). SV-OOAs and LV-OOAs were identified as gasSOAs and aqSOAs according to their sensitivities to the atmospheric oxidation capacity and AWC. In addition, aqueous-phase processing was found to be the dominant pathway for SOA formation when the AWC concentration was higher than 80 µg m-3. As an influential factor for nitrate and SOA formation, AWC could be greatly affected by RH and the concentrations of inorganic species. Sulfate, which was mainly contributed by anthropogenic emissions, was demonstrated to be a significant factor for active aqueous phase reactions, although SO2 has been dramatically reduced in recent years. Above all, this study revealed the significant role of AWC in current pollution episode in winter, and will assist in establishing future measures for pollution mitigation.


Asunto(s)
Contaminantes Atmosféricos , Nitratos , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , China , Monitoreo del Ambiente , Nitratos/análisis , Material Particulado/análisis , Estaciones del Año , Agua
9.
Sci Total Environ ; 782: 146802, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-33838366

RESUMEN

Volatile organic compounds (VOCs) are essential in secondary organic aerosol (SOA) formation due to their dual roles as precursors and oxidant producers. In order to explore the dominant contributions of SOA formation from VOCs in central China, 53 VOC species were observed with proton transfer reaction-mass spectrometry (PTR-MS) and canister grab samples in Xinxiang, a mid-sized city located in Henan Province, from November 5th to December 3rd, 2018. The result showed that anthropogenic emissions were intensive compared with many studies in the world. Among the observed VOCs, benzene and toluene had the largest SOA formation potential (SOAFP), and their contributions in SOA formation kept stable with the aggravation of pollution. Among VOCs, formaldehyde was the strongest radical contributor, and the contribution of acetaldehyde was also found significant in this study, especially in polluted periods. Based on the positive matrix factorization (PMF) model, benzenoids (mainly single-ring aromatics) were majorly emitted from chemical process, solvent evaporation, and residential heating, with a total fraction of 75%, and these sources were estimated to have largest SOAFP. However, thermal power generation, chemical process, and solvent evaporation had highest radical contribution rates. According to the backward trajectory analysis, the VOC concentrations were dominated by local emissions. Emissions in the surrounding provinces occupied fractions of 33%-42% in the five sources. Therefore, regional collaborative emission reduction is also important.

11.
Talanta ; 194: 888-894, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30609620

RESUMEN

The chemi-ionization reaction is a high-efficiency pathway to produce molecular ions in plasma, however, it has rarely been applied in mass spectrometry to directly produce analyte ions. In this study, a novel chemi-ionization technique for mass spectrometry was applied for the direct and ultrasensitive detection of gaseous aldehydes. The ionization technique was enacted by a recently observed chemi-ionization reaction: the efficient proton transfer from H2O to oxygenated compounds was stimulated by vacuum ultraviolet (VUV)-excited CH2Cl2. By analyzing a series of aliphatic aldehydes (C2-C5) and benzaldehyde with different proton affinities (PAs) and polarities, the ionization features of the new ionization method were investigated for the first time. The chemi-ionization of aldehydes presented soft ionization characteristics with fragmentation patterns analogous to that of VUV photoionization. The method showed ultrahigh sensitivities toward aldehydes (up to 1108 ±â€¯6 counts pptv-1 for benzaldehyde in 10 s acquisition time). The corresponding 3σ limits of detection (LODs) achieved 0.30-0.69 pptv, which are equivalent of 1.35-1.92 ng m-3, for the compounds investigated. The humidity experiments revealed that the moisture in the sample gas had an evident impact on the detection efficiency of the analyte and the influence was PA dependent. In addition, the applicability of this ionization mode was further tested by analysis of aldehydes in cigarette smoke. This study provides a promising ionization method for greatly improving the current on-line detection sensitivity of volatile aldehydes.

12.
J Immunol Res ; 2018: 4263520, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30410941

RESUMEN

Adoptive chimeric antigen receptor-modified T or NK cells (CAR-T or CAR-NK) offer new options for cancer treatment. CAR-T therapy has achieved encouraging breakthroughs in the treatment of hematological malignancies. However, their therapeutic efficacy against solid tumors is limited. New regimens, including combinations with chemical drugs, need to be studied to enhance the therapeutic efficacy of CAR-T or NK cells for solid tumors. An epithelial cell adhesion molecule- (EpCAM-) specific second-generation CAR was constructed and transduced into NK-92 cells by lentiviral vectors. Immune effects, including cytokine release and cytotoxicity of the CAR-NK-92 cells against EpCAM-positive colon cancer cells, were evaluated in vitro. Synergistic effects of regorafenib and CAR-NK-92 cells were analyzed in a mouse model with human colorectal cancer xenografts. The CAR-NK-92 cells can specifically recognize EpCAM-positive colorectal cancer cells and release cytokines, including IFN-γ, perforin, and granzyme B, and show specific cytotoxicity in vitro. The growth suppression efficacy of combination therapy with regorafenib and CAR-NK-92 cells on established EpCAM-positive tumor xenografts was more significant than that of monotherapy with CAR-NK-92 cells or regorafenib. Our results provided a novel strategy to treat colorectal cancer and enhance the therapeutic efficacy of CAR-modified immune effector cells for solid tumors.


Asunto(s)
Antineoplásicos/uso terapéutico , Vacunas contra el Cáncer/inmunología , Neoplasias Colorrectales/terapia , Inmunoterapia Adoptiva/métodos , Células Asesinas Naturales/fisiología , Compuestos de Fenilurea/uso terapéutico , Piridinas/uso terapéutico , Animales , Línea Celular Tumoral , Neoplasias Colorrectales/inmunología , Terapia Combinada , Citotoxicidad Inmunológica , Modelos Animales de Enfermedad , Molécula de Adhesión Celular Epitelial/inmunología , Femenino , Humanos , Interferón gamma/metabolismo , Células Asesinas Naturales/trasplante , Ratones , Ratones SCID , Receptores Quiméricos de Antígenos/genética , Carga Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Anal Chim Acta ; 1035: 119-128, 2018 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-30224129

RESUMEN

Taste and odor (T&O) compounds are widespread in water environments and have attracted considerable public attention. Nowadays, the standard detections of these chemicals rely mainly on off-line methods such as GC-MS or evaluation by trained analysts' senses. In this study, we report a method for the rapid detection of T&O compounds in water by exploiting a newly invented chemi-ionization source, in combination with headspace vapor measurement at room temperature. The calibrated limits of detection (LODs) of 2-methylbutyraldehyde, methyl tert-butyl ether (MTBE), methyl methacrylate (MMA), 2-isobutyl-3-methyoxypyrazine (IBMP), and 2-isopropyl-3-methoxypyrazine (IPMP) are in the range of 3.5-50.2 ng L-1, and the estimated LODs of 2-methylisoborneol (2-MIB) and geosmin (GSM) are 0.25 and 0.77 ng L-1, respectively. The calibration results reveal that the instrumental LODs for 2-methylbutyraldehyde, MTBE, MMA, ß-cyclocitral, 2-MIB, and GSM are 1-2 orders of magnitude better than the odor thresholds of humans. The accuracy, precision, recovery, and linearity (R2) of the method are tested. Water samples from city tap water and three rivers in Beijing are assessed using this technique, and the typical T&O compositions are observed with concentrations ranging from 0.2 to 297 ng L-1. The new ultra-sensitive rapid detection method shows comparable sensitivities to the existing off-line technique and displays great potential for real-time detection of T&O pollution in water environments.


Asunto(s)
Espectrometría de Masas/métodos , Odorantes/análisis , Contaminantes Químicos del Agua/análisis , Aldehídos/análisis , Canfanos/análisis , China , Diterpenos/análisis , Límite de Detección , Naftoles/análisis , Pirazinas/análisis , Reproducibilidad de los Resultados , Ríos/química , Gusto
14.
Environ Pollut ; 234: 960-968, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29665636

RESUMEN

Gasoline vehicles are a major source of anthropogenic secondary organic aerosols (SOAs). However, current models based on known precursors fail to explain the substantial SOAs from vehicle emissions due to the inadequate understanding of the formation mechanism. To provide more information on this issue, the formation of SOAs from ozonolysis of four light-duty gasoline vehicle exhaust systems was investigated with a vacuum ultraviolet photoionization mass spectrometer (VUV-PIMS). Remarkable SOAs formation was observed and the SOAs were primarily aliphatic alkenes. PI mass spectra of the SOAs from all vehicles exhibited similar spectral patterns (a regular mass group with m/z at 98, 112, 126 …). Interestingly, most carbonyl products of aliphatic alkenes observed as major gaseous products have specific molecular weights, and the main formation pathway of SOAs can be explained well using aldol condensation reactions of these carbonyls. This is a direct observation of the aldol condensation as a dominated pathway for SOAs formation, and the first report on the composition and formation mechanism of the SOAs from the ozonolysis of gasoline vehicle exhaust is given. The study reveals that low molecular weight alkenes may play a more significant role in vehicle-induced SOAs formation than previously believed. More importantly, the PI mass spectra of SOAs from vehicles show similarities to the field aerosol sample mass spectra, suggesting the possible significance of the aldol condensation reactions in ambient aerosol formation. Since carbonyls are a major degradation product of biogenic and anthropogenic VOCs through atmospheric oxidation processes, the mechanism proposed in this study can be applied more generally to explain aerosol formation from the oxidation of atmospheric hydrocarbons.


Asunto(s)
Aerosoles/química , Contaminantes Atmosféricos/química , Gasolina/análisis , Modelos Químicos , Emisiones de Vehículos/análisis , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Hidrocarburos , Peso Molecular , Oxidación-Reducción , Ozono
15.
Environ Pollut ; 232: 65-72, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28917820

RESUMEN

To further explore the composition and distribution of secondary organic aerosol (SOA) components from the photo-oxidation of light aromatic precursors (toluene, m-xylene, and 1,3,5-trimethylbenzene (1,3,5-TMB)) and idling gasoline exhaust, a vacuum ultraviolet photoionization mass spectrometer (VUV-PIMS) was employed. Peaks of the molecular ions of the SOA components with minimum molecular fragmentation were clearly observed from the mass spectra of SOA, through the application of soft ionization methods in VUV-PIMS. The experiments comparing the exhaust-SOA and light aromatic mixture-SOA showed that the observed distributions of almost all the predominant cluster ions in the exhaust-SOA were similar to that of the mixture-SOA. Based on the characterization experiments of SOA formed from individual light aromatic precursors, the SOA components with molecular weights of 98 and 110 amu observed in the exhaust-SOA resulted from the photo-oxidation of toluene and m-xylene; the components with a molecular weight of 124 amu were derived mainly from m-xylene; and the components with molecular weights of 100, 112, 128, 138, and 156 amu were mainly derived from 1,3,5-TMB. These results suggest that C7-C9 light aromatic hydrocarbons are significant SOA precursors and that major SOA components originate from gasoline exhaust. Additionally, some new light aromatic hydrocarbon-SOA components were observed for the first time using VUV-PIMS. The corresponding reaction mechanisms were also proposed in this study to enrich the knowledge base of the formation mechanisms of light aromatic hydrocarbon-SOA compounds.


Asunto(s)
Aerosoles/análisis , Gasolina/análisis , Procesos Fotoquímicos , Emisiones de Vehículos/análisis , Hidrocarburos Aromáticos , Espectrometría de Masas , Peso Molecular , Oxidación-Reducción , Tolueno , Xilenos/análisis
16.
Anal Chem ; 90(2): 1301-1308, 2018 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-29227091

RESUMEN

The mass spectrometry analysis of oxygenated volatile organic compounds (OVOCs) remains challenging due to their limited ionization efficiencies. In this study, we surprisingly found that, under vacuum-UV (VUV) excitation, a gaseous mixture of CH2Cl2/H2O/analyte (OVOCs) in N2 buffer generated large amounts of H3O+ and protonated analyte even when the photon energy was lower than the ionization energy of the neutral species involved. In contrast to those obtained with VUV photoionization alone, the signal intensities of oxygenated organics can be amplified by more than 3 orders of magnitude. The isotope tracing experiment revealed that the proton donor is water, and the dependence of the signal intensities on the VUV photon intensities verified that the reaction was a single-photon process. The observed ionization process is assigned as an undocumented chemi-ionization reaction in which a complex formed from the ion-pair state CH2Cl2*, H2O, and analyte and then autoionized to produce the protonated analyte with the aid of the reorganization energy released from the formation of CH2O and HCl. Essentially, here we present an efficient chemi-ionization method for the direct protonation of oxygenated organics. By the method, the mass spectrometric sensitivities toward acetic acid, ethanol, aldehyde, diethyl ether, and acetone were determined to be 224 ± 17, 245 ± 5, 477 ± 14, 679 ± 11, and 684 ± 6 counts pptv-1, respectively, in 10 s acquisition time. In addition, the present ionization process provides a new method for the generation of a high-intensity H3O+ source (∼1011 ions s-1, measured by ion current) by which general organics can be indirectly protonated via a conventional proton-transfer reaction. These results open new aspects of chemi-ionization reactions and offer new technological applications that have the potential to greatly improve mass spectrometry sensitivity for detecting trace gaseous organics.

17.
Talanta ; 178: 636-643, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-29136874

RESUMEN

Many organic amines that comprise a benzene ring are policy-sensitive because of their toxicity and links to social harm. However, to date, detection of such compounds mainly relies on offline methods. This study proposes an online pptv (parts per trillion by volume) level of detection method for amines, using the recently-built vacuum ultraviolet photoionization mass spectrometer (VUV-PIMS) combined with a new doping technique. Thus, the dichloromethane doping-assisted photoionization mass spectra of aniline, benzylamine, phenethylamine, amphetamine, and their structural isomers were recorded. The dominant characteristic mass peaks for all amines are those afforded by protonated amines and the amino radical-loss. The signal intensities of the amines were enhanced by 60-130 times compared to those recorded without doping assistance. Under 10s detection time, the sensitivities of aniline and benzylamine in the gas phase were determined as 4.0 and 2.7 countspptv-1, with limits of detection (LODs) of 36 and 22 pptv, respectively. Notably, the detection efficiency of this method can be tenfold better in future applications since the ion transmission efficiency of the mass spectrometer was intentionally reduced to ~ 10% in this study. Therefore, dichloromethane doping-assisted photoionization mass spectrometry has proven to be a highly promising on-line approach to amine detection in environmental and judicial supervision and shows great potential for application in the biological field.


Asunto(s)
Aminas/análisis , Detección de Abuso de Sustancias/métodos , Límite de Detección , Espectrometría de Masas/métodos , Cloruro de Metileno/química
18.
Expert Rev Anticancer Ther ; 17(12): 1099-1106, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29048935

RESUMEN

INTRODUCTION: Chimeric antigen receptor modified T cell (CAR-T) therapy has achieved encouraging breakthroughs in the treatment of hematological malignancies. Nevertheless, this success has not yet been extrapolated to solid tumors. This review focuses on new clinical regimens that could improve the therapeutic efficacy of CAR-T in solid tumors. Areas covered: Herein, the authors reviewed recent clinical trials using CAR-T therapies for the treatment of solid tumors. Specifically, this review covered the following areas: (1) the current status of CAR-T cells in the treatment of solid tumors; (2) the major factors constraining the efficacy of CAR-T cells in solid tumors; and (3) opinions regarding the future of CAR-T as a treatment for solid tumors. Expert commentary: While some recent studies have shown promising results, the ultimate success of CAR-T therapies in solid tumor patients will require the following improvements to clinical regimens: (1) local delivery of CAR-T cells; (2) combination of CAR-T cells with chemotherapeutic drugs to treat metastatic tumors; (3) combination of CAR-T with immune checkpoint inhibitors; (4) combination therapy using CAR-T cells targeting two different antigens; and (5) the use of CAR-T as a strategy to prevent tumor recurrence and metastasis after radical resection.


Asunto(s)
Neoplasias/terapia , Receptores de Antígenos de Linfocitos T/inmunología , Linfocitos T/inmunología , Animales , Antineoplásicos/administración & dosificación , Terapia Combinada , Humanos , Inmunoterapia/métodos , Recurrencia Local de Neoplasia/prevención & control , Neoplasias/inmunología
19.
J Immunol Res ; 2017: 6915912, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29423418

RESUMEN

The chimeric antigen receptor-modified immune effector cell (CAR-T and CAR-NK) therapies are newly developed adoptive treatments of cancers. However, their therapeutic efficacy against solid tumors is limited. Combining CAR-T or CAR-NK cells with chemotherapeutic drugs to treat solid tumor may be a promising strategy. We developed an epidermal growth factor- (EGFR-) specific third-generation CAR. NK-92 cells were modified with the CAR by lentivirus infection. The specific killing ability of the CAR-modified NK-92 cells (CAR-NK-92) against renal cell carcinoma (RCC) cell lines was confirmed in vitro. The synergistic effects of cabozantinib and EGFR-specific CAR-NK-92 cells were investigated in vitro and in vivo. Our results showed that the CAR-NK-92 cells lyse RCC cells in an EGFR-specific manner. Treatment with cabozantinib could increase EGFR and decrease PD-L1 membrane surface expression in RCC cells and enhance the killing ability of CAR-NK-92 cells against the RCC cells in vitro. Furthermore, the CAR-NK-92 cells show synergistic therapeutic efficacy with cabozantinib against human RCC xenograft models. Our results provided the basis for combination with chemotherapy as a novel strategy for enhancing the therapeutic efficacy of CAR-modified immune effector cells for solid tumors.


Asunto(s)
Anilidas/uso terapéutico , Antineoplásicos/uso terapéutico , Carcinoma de Células Renales/tratamiento farmacológico , Inmunoterapia Adoptiva/métodos , Neoplasias Renales/tratamiento farmacológico , Células Asesinas Naturales/inmunología , Piridinas/uso terapéutico , Animales , Línea Celular , Terapia Combinada , Citotoxicidad Inmunológica , Receptores ErbB/inmunología , Femenino , Humanos , Células Asesinas Naturales/trasplante , Ratones , Ratones SCID , Receptores de Antígenos/genética , Proteínas Recombinantes de Fusión/genética , Ensayos Antitumor por Modelo de Xenoinjerto
20.
Sci Rep ; 6: 36820, 2016 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-27905552

RESUMEN

Doping has been used to enhance the ionization efficiency of analytes in atmospheric pressure photoionization, which is based on charge exchange. Compounds with excellent ionization efficiencies are usually chosen as dopants. In this paper, we report a new phenomenon observed in low-pressure photoionization: Protonation enhancement by dichloromethane (CH2Cl2) doping. CH2Cl2 is not a common dopant due to its high ionization energy (11.33 eV). The low-pressure photoionization source was built using a krypton VUV lamp that emits photons with energies of 10.0 and 10.6 eV and was operated at ~500-1000 Pa. Protonation of water, methanol, ethanol, and acetaldehyde was respectively enhanced by 481.7 ± 122.4, 197.8 ± 18.8, 87.3 ± 7.8, and 93.5 ± 35.5 times after doping 291 ppmv CH2Cl2, meanwhile CH2Cl2 almost does not generate noticeable ions itself. This phenomenon has not been documented in the literature. A new protonation process involving in ion-pair and H-bond formations was proposed to expound the phenomenon. The observed phenomenon opens a new prospect for the improvement of the detection efficiency of VUV photoionization.

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