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Background: The purpose of this study was to use a network meta-analysis (NMA) to compare the effects of aerobic training (AT), resistance training (RT), combined training (CBT), and high-intensity interval training (HIIT) on adult heart rate variability (HRV). Methods: We searched PubMed, the Cochrane Library, Embase, the Web of Science, Wanfang Data, and the China National Knowledge Infrastructure to identify randomized controlled trials on the effects of exercise on HRV in adults. The search was conducted from the outset of these databases to April 2023. Two reviewers independently screened the retrieved articles, extracted raw data from the relevant studies, and assessed the possible risk of bias in the included studies. Results: The NMA showed that HIIT had the greatest effect on the low-frequency (LF) power/high-frequency (HF) power ratio, standard deviation of normal-normal intervals (SDNN), and root mean square of successive differences between adjacent normal-to-normal intervals (RMSSD) (surface under the cumulative ranking curve (SUCRA) = 99.75%, 98.7%, and 84.9%); CBT had the greatest effect on the LF power (SUCRA = 66.3%); RT had the greatest effect on the HF power (SUCRA = 72.5%). Conclusions: Our NMA and SUCRA ranking results suggest that in adults, HIIT is the most effective exercise modality in improving the SDNN, RMSSD, and LF/HF power ratio; RT for the HF power; CBT for the LF power. Any NMA conducted in the future must fully explore the effects of different exercise modalities on HRV in adult subgroups of different ages and genders. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=424054, identifier: CRD42023424054.
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BACKGROUND: Portal vein thrombosis (PVT) is a common complication of liver cirrhosis, yet there are fewer studies about predictors of PVT recanalization. We aimed to further explore the predictors of recanalization in cirrhotic PVT to facilitate accurate prediction of patients' clinical status and timely initiation of appropriate treatment and interventions. To further investigate the benefits and risks of anticoagulant therapy in cirrhotic PVT patients. METHODS: A retrospective cohort study of patients with cirrhotic PVT in our hospital between January 2016 and December 2022, The primary endpoint was to analyze predictors of PVT recanalization by COX regression. Others included bleeding rate, liver function, and mortality. RESULTS: This study included a total of 82 patients, with 30 in the recanalization group and 52 in the non-recanalization group. Anticoagulation therapy was the only independent protective factor for portal vein thrombosis recanalization and the independent risk factors included massive ascites, history of splenectomy, Child-Pugh B/C class, and main trunk width of the portal vein. Anticoagulation therapy was associated with a significantly higher rate of PVT recanalization (75.9% vs. 20%, log-rank P < 0.001) and a lower rate of PVT progression (6.9% vs. 54.7%, log-rank P = 0.002). There was no significant difference between different anticoagulation regimens for PVT recanalization. Anticoagulation therapy did not increase the incidence of bleeding complications(P = 0.407). At the end of the study follow-up, Child-Pugh classification, MELD score, and albumin level were better in the anticoagulation group than in the non-anticoagulation group. There was no significant difference in 2-year survival between the two groups. CONCLUSION: Anticoagulation, massive ascites, history of splenectomy, Child-Pugh B/C class, and main portal vein width were associated with portal vein thrombosis recanalization. Anticoagulation may increase the rate of PVT recanalization and decrease the rate of PVT progression without increasing the rate of bleeding. Anticoagulation may be beneficial in improving liver function in patients with PVT in cirrhosis.
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Anticoagulantes , Cirrosis Hepática , Vena Porta , Trombosis de la Vena , Humanos , Cirrosis Hepática/complicaciones , Masculino , Femenino , Estudios Retrospectivos , Trombosis de la Vena/etiología , Trombosis de la Vena/tratamiento farmacológico , Persona de Mediana Edad , Anticoagulantes/uso terapéutico , Factores de Riesgo , Ascitis/etiología , Anciano , Progresión de la Enfermedad , Adulto , EsplenectomíaRESUMEN
The concerns about the fate of per- and polyfluoroalkyl substances (PFAS) in the atmosphere are continuously growing. In this study, size-fractionated particles, gas, and rainwater samples were simultaneously collected in Shijiazhuang, China, to investigate the multiphase distribution of PFAS in the atmosphere. Perfluoroalkyl carboxylic acids (PFCAs) dominated the total concentration of PFAS in atmospheric media. A strong positive relationship (0.79 < R2 < 0.99) was observed between the concentration of PFCAs and organic matter fraction (fOM) in different particle size fractions, while no such relationship for perfluoroalkyl sulfonic acids (PFSAs) and fOM, suggesting fOM may be an important factor influencing the size-dependent distribution of PFCAs. Temperature played a key role in the gas-particle partitioning of PFAS, while it did not significantly affect their particle-size-dependent distribution. The associative concentration fluctuation of particle and particle-bound PFAS during precipitation suggested that precipitation scavenging was an important mechanism for the removal of PFAS from the atmosphere. Furthermore, temporary increases in atmospheric PFAS concentrations were observed during the precipitation. Fugacity ratios of PFAS in rainwater and gas phase (log fR/fG ranged between 2.0 and 6.6) indicated a strong trend for PFAS to diffuse from the rainwater to the gas phase during the precipitation, which may explain that the concentration of PFAS in the gas phase continued to increase even at the end of the precipitation.
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Atmósfera , Fluorocarburos , Tamaño de la Partícula , Fluorocarburos/análisis , Atmósfera/química , Contaminantes Atmosféricos/análisis , Lluvia/química , China , Monitoreo del Ambiente , Gases , Precipitación QuímicaRESUMEN
The occurrence of per- and polyfluoroalkyl substances (PFAS) was investigated inside two manufacturing facilities in China. Levels, profiles, and spatial distribution of the detected PFAS were found to be distinctly site-specific and influenced by the area's historic function, production structure of the plant, downpour-induced accidental pollution, and variations in the adsorption and transport of compounds. Very high concentrations of PFAS [mainly C4 and C8 perfluoroalkyl sulfonic acids (PFSAs)] were found in topsoil and groundwater from both plants, with the highest values of 4.89 × 106 µg/kg dw and 1.10 × 104 µg/L, respectively. Elevated concentrations of perfluoroalkyl carboxylic acids (PFCAs) in this study were attributed to their unintentional formation during the electrochemical fluorination process, which might be an overlooked source of PFCA. PFAS generally showed decreasing trends from shallow layers to the bottom of the soil core and demonstrated some downward migrations at different soil depths with time, and C4-C8 PFAS presented a deeper seepage than their long-chain homologues. Total organic carbon appeared to be more important for PFAS sorption to the topsoil than to the soil core. Workers were at potential risk of exposure to perfluorooctanesulfonic acid via soil at production and storage related sites. This study provides a critical reference for the systematic control of PFAS pollution around manufacturing facilities and a proof for an overlooked source of PFCA.
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Ácidos Alcanesulfónicos , Fluorocarburos , Contaminantes Químicos del Agua , Humanos , Monitoreo del Ambiente , Ácidos Alcanesulfónicos/análisis , Fluorocarburos/análisis , Instalaciones Industriales y de Fabricación , Ácidos Carboxílicos , China , Suelo , Contaminantes Químicos del Agua/análisisRESUMEN
A vital bioactive component of marine resources is Holothuria leucospilota polysaccharides (HLP). This study examined whether HLP could regulate intestinal flora to treat loperamide-induced constipation. Constipated mice showed signs of prolonged defecation (up by 60.79 min) and a reduced number of bowel movements and pellet water content (decreased by 12.375 and 11.77%, respectively). The results showed that HLP treatment reduced these symptoms, reversed the changes in related protein expression levels in the colon, and regulated the levels of active peptides associated with the gastrointestinal tract in constipated mice, which significantly improved water-electrolyte metabolism and enhanced gastrointestinal motility. Meanwhile, it was found that intestinal barrier damage was reduced and the inflammatory response was inhibited through histopathology and immunohistochemistry. As a means to further relieve constipation symptoms, treatment with low, medium, and high HLP concentrations increased the total short-chain fatty acid (SCFA) content in the intestine of constipated mice by 62.60 µg/g, 138.91 µg/g, and 126.51 µg/g, respectively. Moreover, an analysis of the intestinal flora's gene for 16S rRNA suggested that the intestinal microbiota was improved through HLP treatment, which is relevant to the motivation for the production of SCFAs. In summary, it was demonstrated that HLP reduced loperamide-induced constipation in mice.
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Holothuria , Loperamida , Ratones , Animales , Loperamida/efectos adversos , ARN Ribosómico 16S , Estreñimiento/inducido químicamente , Estreñimiento/tratamiento farmacológico , Polisacáridos/farmacología , Polisacáridos/uso terapéutico , AguaRESUMEN
It is extremely important to analyze the contaminative behaviors of Perfluoroalkyl acids (PFAAs) due to their serious threats to urban environments which are closely related to humans. Current study aimed to explore the distribution, source apportionment and ecological risk assessment of PFAAs in surface water from Shijiazhuang, China. The concentrations of ∑PFAAs ranged from 19.5 to 125.9 ng/L in the investigation area. Perfluorobutanesulfonic acid (PFBS) and perfluoropentanoic acid (PFPeA) were the predominant contaminants (mean value: 14.3 ng/L and 16.6 ng/L, respectively). The distribution of PFAAs according to geospatial analysis and hierarchical clustering analysis (HCA) showed that higher levels of ∑PFAAs were detected in the southern surface water of Shijiazhuang and there was a stepwise decrease from the wet season to the dry season. Furthermore, based on source apportionment, the dominant potential sources were found to be wastewater treatment plant (WWTP) effluents and industrial discharge. The risk quotients (RQs) revealed low ecological risks of all PFAAs for aquatic organisms in Shijiazhuang surface water. Collectively, this study provided basic data for regulatory strategies for controlling PFAA pollutions in urban surface water.
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Ácidos Alcanesulfónicos , Fluorocarburos , Contaminantes Químicos del Agua , Humanos , Fluorocarburos/análisis , Ríos , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Agua/análisis , China , Ácidos Alcanesulfónicos/análisisRESUMEN
Coastal lagoons provide many important services to human society, but their year-round use for aquaculture introduces large amounts of sewage. The contamination of antibiotic resistance genes (ARGs) is therefore of great concern. In this study, 50 ARGs subtypes, two integrase genes (intl1, intl2), and 16S rRNA genes were detected by high-throughput quantitative PCR, and standard curves of all target genes were prepared for quantification. The occurrence and distribution of ARGs in a typical coastal lagoon (XinCun lagoon, China) were comprehensively explored. We detected 44 and 38 subtypes of ARGs in the water and sediment, respectively, and discuss the various factors influencing the fate of ARGs in the coastal lagoon. Macrolides-lincosamides-streptogramins B was the primary ARG type, and macB was the predominant subtype. Antibiotic efflux and antibiotic inactivation were the main ARG resistance mechanisms. The XinCun lagoon was divided into eight functional zones. The ARGs showed a distinct spatial distribution owing to the influence of microbial biomass and anthropogenic activity in different functional zones. Fishing rafts, abandoned fish ponds, the town sewage zone, and mangrove wetlands provided a large quantity of ARGs to the XinCun lagoon. Nutrients and heavy metals also significantly correlated with the fate of the ARGs, especially NO2--N and Cu, which cannot be ignored. It is noteworthy that lagoon-barrier systems coupled with persistent pollutant inputs result in coastal lagoons acting as a "buffer pool" for ARGs, which can then accumulate and threaten the offshore environment.
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Antibacterianos , Genes Bacterianos , Animales , Humanos , Antibacterianos/análisis , Aguas del Alcantarillado , ARN Ribosómico 16S/genética , Farmacorresistencia Microbiana/genética , ChinaRESUMEN
Anisotropic nanoparticles possess high sensitivity to the environmental refractive index that is strongly dependent on their active facets. As a polyhedron exclusively enclosed by active facets, Au nano-rhombic dodecahedra (AuNRDs) with multiple tips and edges have been less explored with respect to their capability in surface plasmon resonance (SPR) sensing. Here, we report on the use of AuNRDs in the colorimetric detection of S2- and Hg2+. Upon Ag coating, the AuNRDs can probe S2- with high sensitivity and selectivity due to the chemical transformation of Ag into Ag2S. Furthermore, Hg2+ can be detected by the SPR of the AuNRDs based on the formation of HgS from the Ag2S shell on the AuNRDs. These changes in the morphology and composition of the AuNRDs have been confirmed by electron microscopy and elemental mapping. The promising colorimetric response of Ag-coated AuNRDs to S2- is visible through the naked eye and the change in the SPR of the AuNRDs shifted linearly with an increasing concentration of S2- in the range of 0.5-15 µM, with a detection limit of 0.26 µM. The change in the SPR of the Ag2S-coated AuNRDs also indicates a dependence on the concentration of Hg2+ in the range from 0 to 100 µM, with a detection limit of 38 nM. The limits of detection are lower or close to the maximum allowable levels of S2- and Hg2+ for drinking water defined by national or international administrations. These seminal results unveil new opportunities for the AuNRDs and other anisotropic nanostructures with active facets in SPR-based sensing applications.
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Mercurio , Nanopartículas del Metal , Colorimetría/métodos , Oro/química , Nanopartículas del Metal/química , Resonancia por Plasmón de Superficie/métodosRESUMEN
Sodium p-perfluorous nonenoxybenzenesulfonate (OBS), a novel alternative to perfluorooctane sulfonic acid (PFOS), has been widely used in various fields in China and has certain toxic effects similar to PFOS. This study monitored OBS and 15 legacy PFASs in surface water, sediment, soil, and crucian carp near a fluorochemical manufacturing factory (FMF) in Suqian, China, focusing on the emission, isomer-specific environmental fate, and transformation of OBS. One to four orders of magnitude higher concentrations of OBS than other polyfluoroalkyl substances (PFASs) in all samples indicate that industrial emission is an important point source of OBS in the surrounding environment. The concentrations of OBS in surface water, sediment, and soil decreased exponentially as the distance from the FMF increases. The proportions of OBS-c, the dominant isomer, increased in the order: water (75.5 ± 6.4%), sediment (85.7 ± 10%), fish (muscle: 94.1 ± 0.99%; blood: 93.5 ± 1.4%), suggesting its preferential accumulation in sediment and fish than other isomers. Mono-hydroxylated transformation products of OBS were first identified in water, sediment, and fish, suggesting its hydroxylation may exist in the real environment. The transformation of OBS may explain its significantly lower bioaccumulation than PFOS in fish. However, considering the higher BAF of OBS than the regulatory bioaccumulation criterion and the possible stronger toxicity of its transformation products, further studies on its bioaccumulation and transformation are warranted.
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Ácidos Alcanesulfónicos , Carpas , Fluorocarburos , Contaminantes Químicos del Agua , Ácidos Alcanesulfónicos/análisis , Animales , China , Monitoreo del Ambiente , Fluorocarburos/análisis , Instalaciones Industriales y de Fabricación , Suelo , Agua , Contaminantes Químicos del Agua/análisisRESUMEN
The penetration of organophosphate triesters (tri-OPEs) and diesters (di-OPEs) across the blood-brain barrier and their influencing factors remain unclear in humans. In this study, 21 tri-OPEs and 8 di-OPEs were measured in 288 paired serum and cerebrospinal fluid (CSF) samples collected in Jinan, China. Six tri-OPEs were frequently detected in both serum and CSF, with median concentrations ranging from 0.062 to 1.62 and 0.042-1.11 ng/mL, respectively. Their penetration efficiencies across the blood-CSF barrier (BCSFB) (RCSF/serum, CCSF/Cserum) were calculated at 0.667-2.80, and these efficiencies first increased and then decreased with their log Kow values. The reduced penetration efficiencies of triphenyl phosphate (TPHP) and 2-ethylhexyl diphenyl phosphate (EHDPP) may be attributed to their strong binding affinities for human serum albumin and p-glycoprotein due to their high hydrophobicity and aryl structure, as indicated by molecular docking. This suggests that active efflux transport may be involved in the penetration of TPHP and EHDPP in addition to passive diffusion similar to the other four tri-OPEs. Di-OPEs were found in few serum samples and even fewer CSF samples, indicating their limited BCSFB permeability. This may be due to their high polarity, low hydrophobicity, and ionic state in blood. This study has important implications for understanding the neurotoxicity of tri-OPEs and di-OPEs and the underlying mechanisms.
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Retardadores de Llama , Barrera Hematoencefálica/química , China , Monitoreo del Ambiente , Ésteres , Retardadores de Llama/análisis , Humanos , Simulación del Acoplamiento Molecular , Organofosfatos , FosfatosRESUMEN
Per- and polyfluoroalkyl substances (PFASs) are widely detected in the environment and may cause adverse human health effects after exposure. Studies on the effect of PFASs on some health end points, including cancer, are still limited and show inconsistent results. In this research, 319 participants were recruited from Shandong Province, East China, consisting of patients with thyroid cancer and healthy controls. Seven novel and legacy PFASs were frequently detected (detection rate > 75%) in the serum samples of the participants. The concentrations of perfluorooctanoic acid (PFOA) were the highest in the case and control groups. Males showed significantly higher concentrations of PFASs than females. Exposure to PFASs was inversely associated with the risk of thyroid cancer. In the control group, we identified significant positive associations between PFASs and free thyroxine (FT4) as well as between PFOA and thyroid stimulating hormone (TSH) in females. A significant negative association between perfluorononanoic acid (PFNA) and triiodothyronine (T3) was observed in males. Our results suggest that exposure to certain PFASs could interfere with thyroid function. To our knowledge, this is the first case-control study demonstrating associations between novel and legacy PFASs in human and thyroid cancer.
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Ácidos Alcanesulfónicos , Contaminantes Ambientales , Fluorocarburos , Neoplasias de la Tiroides , Ácidos Alcanesulfónicos/análisis , Estudios de Casos y Controles , China/epidemiología , Femenino , Fluorocarburos/análisis , Humanos , Masculino , Neoplasias de la Tiroides/epidemiologíaRESUMEN
Human exposure to per- and polyfluoroalkyl substances (PFASs) has gained worldwide attention due to their widespread presence in the environment and adverse health effects, but the exposure assessment in the elderly is still lacking. This study aimed to assess exposures to 3 emerging PFASs (chlorinated polyfluoroalkyl ether sulfonic acids, Cl-PFESAs) and 15 legacy PFASs. The temporal variability of internal exposures and intake amounts of these PFASs were evaluated among a population of 76 healthy elderly adults (age: 60-69) in Jinan, China over 5 consecutive months. Fifteen PFASs were detected in whole blood with the mean total concentration (ΣPFAS) at 20.1 ng/mL (range: 5.0-135.9 ng/mL) dominated by perfluorooctanoic acid (PFOA) (9.0 ng/mL), perfluorooctanesulfonic acid (PFOS) (5.3 ng/mL), and 6:2 Cl-PFESA (1.6 ng/mL). Across the 5 month assessment period, significant variation was only observed for short-chain (C4-C7) perfluoroalkyl carboxylic acids, and their variations ranged from 53 to 334%. The median intake of PFOA and PFOS was estimated to be 1.46 and 0.92 ng/kg bw/day, respectively. Regression analysis showed that dietary ingestion, especially fish, was likely an important exposure pathway for PFASs among the elderly adults. Various pathways (e.g., dietary, water, air, and dust) should thus be considered to fully understand human exposure to PFASs.
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Ácidos Alcanesulfónicos , Fluorocarburos , Adulto , Anciano , Ácidos Alcanesulfónicos/análisis , Animales , China , Polvo/análisis , Éteres/análisis , Fluorocarburos/análisis , Humanos , Persona de Mediana Edad , Ácidos Sulfónicos/análisisRESUMEN
OBJECTIVE: To analyze the clinical characteristics and genetic basis of two children patients with CHARGE syndrome. METHODS: The clinical features of the two patients were analyzed, and potential variants were detected by Trio whole exome sequencing (trio-WES) of the probands and their parents. RESULTS: Child 1 has manifested cerebellar vermis dysplasia, enlargement of cerebral ventricles, whereas child 2 manifested with infantile spasm and congenital hip dysplasia. Both children were found to harbor de novo heterozygous variants of the CHD7 gene, namely c.4015C>T (exon 17) and c.5050G>A (exon 22). Based on the guidelines of the American College of Medical Genetics and Genomics, the two variants were rated as pathogenic variants, and the related disease was CHARGE syndrome. Furthermore, child 2 was also found to harbor a novel heterozygous c.6161A>C (p.Gln2054Pro) missense variant of COL12A1 gene, which was rated as possibly pathogenic, and the associated disease was Bethlem myopathy type 2, which is partially matched with the patient' s clinical phenotype. CONCLUSION: The special clinical phenotypes shown by the two children harboring novel CHD7 variants have further expanded the phenotypic spectrum of CHARGE syndrome.
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Síndrome CHARGE , Síndrome CHARGE/genética , ADN Helicasas/genética , Proteínas de Unión al ADN/genética , Pruebas Genéticas , Heterocigoto , Humanos , Mutación , Fenotipo , Secuenciación del ExomaRESUMEN
The production and application of organophosphate esters (OPEs) have dramatically increased in recent years due to their use as a replacement for brominated flame retardants. In this study, 13 OPEs (Σ13OPEs) were analyzed in indoor air samples from kitchens and living rooms in 14 residential homes in Beijing, China. The concentrations of Σ13OPEs in kitchen air samples (mean: 13 ng/m3) were significantly (p < 0.05) higher than in living room air samples (5.0 ng/m3). In addition, paired window surface organic film samples were collected and analyzed to investigate film-air partitioning, exhibiting a mean concentration of Σ13OPEs of 4100 ng/m2. The congener profiles showed that tris(2-chloroisopropyl) phosphate (TCPP) was the predominant compound in both window film samples (48%) and the corresponding indoor air sample (56%). The estimated daily intakes (EDI) of OPEs via indoor air inhalation were 2.8 and 1.4 ng/kg/day for infants and adults, respectively, both of which are below the reference dose values (RfDs). Overall, these findings indicate that OPEs in the indoor air environment of residential homes in Beijing are not likely to pose a health risk to the general population.
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Contaminación del Aire Interior , Retardadores de Llama , Adulto , Contaminación del Aire Interior/análisis , Beijing , China , Polvo/análisis , Monitoreo del Ambiente , Ésteres/análisis , Retardadores de Llama/análisis , Humanos , Organofosfatos/análisisRESUMEN
A selective extraction method with remarkable advantages (i.e., low cost, simplicity, and solvent savings) was developed for the detection of long-chain per- and polyfluoroalkyl substances (PFASs) based on their specific protein affinities. Bovine serum albumin (BSA) was selected to extract PFASs from aqueous samples, which were then desorbed using methanol. Finally, the PFASs were analyzed by high-performance liquid chromatography-tandem mass spectrometry. The optimal extraction conditions were as follows: sample volume, 10 mL; BSA concentration, 2 g/L; equilibration time, 5 min; pH, 3.4; salinity, 6% (w/v) NaCl; and water bath temperature, 80 °C. The protein affinity property was confirmed to be the major extraction mechanism, which significantly increased the selectivity for PFASs. The recoveries of this method for 15 legacy PFASs with CF2 ≥ 6 and three chlorinated polyfluoroether sulfonic acids in tap water, river water, and urine samples with three spiked levels were 73.3-122.3, 83.8-119.4, and 75.0-115.1%, respectively. The method limits of quantification in the three real matrix samples were 4.7-133.3 ng/L. Comparative experiments with conventional solid-phase extraction confirm that the developed approach can be a promising and alternative method for the extraction of PFASs from authentic aqueous samples. Moreover, the proposed method provides a new possibility for screening PFASs exhibiting high bioaccumulation and toxicity.
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Fluorocarburos/análisis , Albúmina Sérica Bovina/química , Espectrometría de Masas en Tándem/métodos , Adsorción , Animales , Bovinos , Cromatografía Líquida de Alta Presión , Fluorocarburos/aislamiento & purificación , Fluorocarburos/orina , Agua Dulce/análisis , Humanos , Concentración de Iones de Hidrógeno , Albúmina Sérica Bovina/metabolismo , Cloruro de Sodio/química , TemperaturaRESUMEN
Colorimetric detection of various target molecules in aqueous solutions based on the non-crosslinking assembly of DNA-functionalized Au nanoparticles (DNA-AuNPs) has been well established in recent years. The extension of DNA-AuNPs to other solvents remains much less explored, despite the practical importance of detection in non-aqueous solutions, such as those containing an organic ingredient that is required or not removable in many contexts. However, the general consideration that DNA is easily denatured and precipitated in organic solvents has been hampering the use of DNA-AuNPs in low polar solvents. Herein, we report a more rapid non-crosslinking assembly of double-stranded (ds) DNA-AuNPs in alcoholic solvents than in aqueous solvents. When the concentration of ethanol in the disperse medium is increased from 0% to 20% (v/v), the rate of non-crosslinking assembly is distinctly increased by a factor of 5-6, whereas the rate is sharply decreased when the ethanol concentration is further increased to 40%. This biphasic kinetics trend could be attributed to the competitive balance between the enhanced intermolecular attraction between dsDNAs and the increased propensity for melting of dsDNA. Rapid naked-eye identification of clear liquors that are encoded by oligonucleotide additives has also been demonstrated by using the alcoholic non-crosslinking assembly of dsDNA-AuNPs as a proof-of-concept.
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Colorimetría/métodos , ADN/análisis , Etanol/química , Nanopartículas del Metal/química , ADN/química , Oro/química , Cinética , Solventes/químicaRESUMEN
Recent studies employing high-resolution mass spectrometry have discovered numerous emerging per- and polyfluoroalkyl substances (PFASs) in the environment, but the lack of authentic standards for these contaminants hampers quantitative evaluation of hazard properties. Here, we tested a matrix-correction methodology for determining the bioaccumulation potential of emerging PFASs based on peak area in crucian carp from Xiaoqing river, China. Fortification experiments of emerging PFASs extracted from surface water and sediment samples demonstrated that the quantification bias in fish tissues was <34% for analytes detected in fish and water. Tissue distribution ratios (TBRs) and whole-body bioaccumulation factors (BAFs) were subsequently calculated by correcting for analyte- and tissue-specific matrix effects. A model evaluation set including seven reference PFASs demonstrated that peak area-based TBRs and BAFs were strongly correlated with those calculated from quantified concentrations (p < 0.05, adjusted r2 > 0.91, slope: 0.99-1.34). Among the detected substances, the trimer acid of hexafluoropropylene oxide and C9 monoether per- and polyfluoroalkyl ether carboxylic acid (PFECA) were identified as bioaccumulative substances. C8 PFECA and C8 monochlorine-substituted perfluoroalkyl carboxylic acid displayed similar BAFs value compared to perfluorooctanoic acid. Overall, the proposed methodology provides a rapid hazard screening tool that could be used to assess emerging contaminants without access to authentic standards.
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Fluorocarburos , Contaminantes Químicos del Agua , Animales , Bioacumulación , China , Monitoreo del Ambiente , RíosRESUMEN
In in vitro cell assays, nominal concentrations of a test chemical are most frequently used in the description of its dose-response curves. Although the biologically effective concentration (BEC) is considered as the most relevant dose metric, in practice, it is very difficult to measure. In this work, we attempted to determine the BEC of long-chain perfluoroalkyl carboxylic acids (PFCAs) in peroxisome proliferator-activated receptor γ (PPARγ) activity assays. In both adipogenesis and transcriptional activity assays with human and mouse cells, PPARγ activity of 7 PFCAs first increased and then decreased with their carbon chain length. The binding affinity of these PFCAs with the ligand-binding domain of PPARγ was measured by fluorescence competitive binding assay and showed very poor correlation with their receptor activity (r2 = 0.002-0.047). Internal concentrations of the PFCAs in the cells were measured by LC-MS/MS. Although their correlation with the receptor activity increased significantly, it is still low (r2 = 0.41-0.82). Using the binding affinity constant, internal concentration, and PPARγ concentration measured by immunoassays, concentrations of receptor-bound PFCAs in cells were calculated, which exhibited excellent correlation with PPARγ activity in both adipogenesis and transcriptional activity assays (r2 = 0.91-0.93). These results demonstrate that the concentration of receptor-bound PFCA is the BEC that dictates its activity on human and mouse PPARγ in cell assays. In the absence of any direct detection method, our approach can be used to calculate the target-site concentration of other ligands.
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Fluorocarburos , PPAR gamma , Animales , Ácidos Carboxílicos , Cromatografía Liquida , Fluorocarburos/toxicidad , Humanos , Ratones , PPAR gamma/genética , Espectrometría de Masas en TándemRESUMEN
Molecular level characterization of dissolved organic sulfur (DOS) by electrospray ionization-Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR MS) is necessary for further understanding of the role of DOS in the environment. Here, ESI spray solvent, a key parameter for ion production during ESI process, was investigated for its effect on the molecular characterization of DOS by ESI-FTICR MS. 100% MeOH as spray solvent was found for the first time to remarkably enhance the ionization efficiency of the majority of CHOS-molecules in NOM, which facilitated a total of 1473 CHOS-molecular formulas with one sulfur atom to be detected. The number of CHOS-molecular formulas obtained using 100%MeOH as spray solvent increased notably over 740 in comparison with those using 50% MeOH aqueous solution (731) or 50% ACN aqueous solution (653). Moreover, due to the enhancement of ionization efficiency of DOS during ESI processes, the tandem mass spectra of the NOM CHOS-molecules could be easily obtained using 100% MeOH as spray solvent, which were hardly obtained using 50% MeOH aqueous solution as spray solvent. The results of the tandem mass spectra suggested the first discovery of organosulfates or sulfonic acids in Suwannee River NOM sample. A simple method based on 100% MeOH as ESI spray solvent for advanced molecular characterization of DOS by ESI-FTICR MS was proposed and applied, and the results revealed more molecular information of DOS in sea DOM samples.
Asunto(s)
Ciclotrones , Espectrometría de Masa por Ionización de Electrospray , Análisis de Fourier , Solventes , AzufreRESUMEN
Storage proteins in the 30â¯K family are ubiquitous in the hemolymph of insects and play important roles in adult metamorphosis, development, egg formation, carrier transport and even host immunity. Some studies have shown that the 30â¯K proteins can inhibit apoptosis and have certain antifungal effects. The silkworm protein Bm30K-19G1 is a low molecular weight apolipoprotein that is abundant in hemolymph of fifth instar larvae. Our previous transcriptome sequencing, real-time PCR analysis and proteomic studies showed that the expression level of the 30â¯K protein gene was significantly up-regulated in the silkworm infected with Beauveria bassiana. In this study, the ORF sequence of Bm30K-19G1 was amplified by PCR. The sequence is 1311â¯bp in length and encodes a 436 amino acid peptide. Bm30K-19G1 was expressed in all tested tissues of fifth instar larvae, with highest expression in fat body and the lowest expression in the midgut. Bm30K-19G1 protein was successfully expressed in the prokaryotic expression system using pET-28a(+) as vector and E. coli Arctic Express (DE3) as the expression bacterium strain. The expressed recombinant Bm30K-19G1 protein has an inhibitory effect on the conidial germination and hyphal growth of B. bassiana. Bm30K-19G1 also inhibited the growth and reproduction of B. bassiana in vivo; the median lethal time of infected silkworms was postponed by 6.4â¯h and the time for death of all infected larvae was postponed by 10â¯h. The results indicated that the silkworm storage protein 30K-19G1 is an antifungal protein against B. bassiana and help to elucidate the molecular mechanism of silkworm resistance against B. bassiana.