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1.
Huan Jing Ke Xue ; 45(5): 2613-2621, 2024 May 08.
Artículo en Chino | MEDLINE | ID: mdl-38629525

RESUMEN

This study selected five typical types of chemical industry volatile organic compounds (VOCs) emission characteristics in China for analysis. The results from 70 source samples showed that alkanes were the dominant VOCs category from synthetic material industry sources, petrochemical industry sources, and coating industry sources (accounting for 43%, 63%, and 68%, respectively); olefins were the main VOCs category from the daily supplies chemical industry (46%); and halogenated hydrocarbons were the dominate VOCs category from specialty chemicals industry account source emissions (43%). Additionally, the machine learning method was applied in this study to analyze the marker components of the above industries. The results showed that decane and tetrahydrofuran were the source markers of the synthetic material industry; n-butanol and toluene were the markers of the daily supplies industry source; 1,2,3-trimethylbenzene and 1,3,5-trimethylbenzene were the markers of the petrochemical industry source; propylene and 3-methyl pentane were the source markers of the coating industry; and P-Xylene and cumene were the markers of the specialty chemicals industry source. The maximum incremental reactivity method (MIR) was used to estimate the ozone formation potential (OFP) of different VOCs-sources. The calculation results showed that when considering per unit TVOCs concentration emissions, the contribution to the ozone generation potential was in the order of the daily supplies chemical industry, specialty chemical industry, petrochemical industry, synthetic material industry, and coating industry. Therefore, we suggest that more attention should be paid to the key active species emitted by various industry sources rather than only the total amount of VOCs emissions in future ozone prevention and control efforts.

2.
Medicine (Baltimore) ; 103(15): e37691, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38608109

RESUMEN

To describe the epidemiology of congenital malformations of the external ear (CMEE). Data were obtained from the Birth Defects Surveillance System in Hunan Province, China, 2016 to 2020. The prevalence of CMEEs is defined as the number of cases per 1000 fetuses (births and deaths at 28 weeks of gestation and beyond) (unit: ‰). Prevalence and 95% confidence intervals (CI) were calculated by the log-binomial method. Chi-square trend tests (χ2trend) were used to determine trends in prevalence by year. P < .05 was considered statistically significant. Crude odds ratios (ORs) were calculated to examine the association of sex, residence, and maternal age with CMEEs. Our study included 847,755 fetuses, and 14,459 birth defects were identified, including 1227 CMEEs (accounted for 8.49% of birth defects). The prevalences of birth defects and CMEEs were 17.06‰ (95%CI: 16.78-17.33) and 1.45‰ (95%CI: 1.37-1.53), respectively. A total of 185 microtia-anotias were identified, accounting for 15.08% of CMEEs, with a prevalence of 0.22‰ (95%CI: 0.19-0.25). And 1042 other CMEEs were identified, accounting for 84.92% of CMEEs. From 2016 to 2020, the prevalences of birth defects were 18.20‰, 18.00‰, 16.31‰, 16.03‰, and 16.47‰, respectively, showing a downward trend (χ2trend =8.45, P < .01); the prevalences of CMEEs were 1.19‰, 1.62‰, 1.80‰, 1.21‰, and 1.35‰, respectively, with no significant trend (χ2trend =0.09, P = .77). CMEEs were more common in males than females (1.60‰ vs 1.27‰, OR = 1.26, 95%CI: 1.12-1.41), in urban areas than in rural areas (1.77‰ vs 1.23‰, OR = 1.45, 95%CI: 1.29-1.62). The prevalences of CMEEs for maternal age < 20, 20-24, 25-29, 30-34, and ≥ 35 were 1.75‰, 1.27‰, 1.44‰, 1.47‰, and 1.58‰, respectively, with no significant difference (P > .05, reference: 25-29). Most CMEEs were diagnosed by clinical examinations (92.34%), and most CMEEs were diagnosed postpartum (within 7 days) (96.25%). In summary, we have presented the epidemiology of CMEEs in Hunan Province, China. CMEEs were more common in males than females, in urban areas than rural areas, whereas there was no significant difference in prevalence of CMEEs by maternal age. We inferred that CMEEs may be mainly related to genetics, and the mechanism needs to be examined in the future.


Asunto(s)
Microtia Congénita , Femenino , Masculino , Humanos , China/epidemiología , Oído Externo , Feto , Edad Materna
3.
Toxics ; 11(3)2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36977014

RESUMEN

The widespread use of wood preservatives, such as chromated copper arsenate (CCA), alkaline copper quaternary (ACQ), and copper azole (CA), may cause environmental pollution problems. Comparative studies on the effect of CCA-, ACQ-, and CA-treated wood on soil contamination are rarely reported, and the behavior of soil metal(loid) speciation affected by preservatives has been poorly understood. Soils under the CCA-, ACQ-, and CA-treated boardwalks were collected to investigate metal(loid) distribution and speciation at the Jiuzhaigou World Natural Heritage site. The results showed that the maximum mean concentrations of Cr, As, and Cu were found in soils under the CCA, CCA, and CCA plus CA treatments and reached 133.60, 314.90, and 266.35 mg/kg, respectively. The Cr, As, and Cu contamination in soils within a depth of above 10 cm was high for all types of boardwalks and limited in the horizontal direction, not exceeding 0.5 m. Cr, As, and Cu in soils were mainly present as residual fractions in all profiles and increased with depth. The proportion of non-residual As in soil profiles under CCA- and CCA plus CA-treatment and exchangeable Cu in CA- and CCA plus CA-treatment were significantly higher than those in the profiles under the other preservative treatments. The distribution and migration of Cr, As, and Cu within soils were influenced by the preservative treatment of trestles, in-service time of trestles, soil properties (e.g., organic matter content), geological disasters (e.g., debris flow), and elemental geochemical behavior. With the CCA treatment for trestles successively replaced by ACQ and CA treatments, the types of contaminants were reduced from a complex of Cr, As, and Cu to a single type of Cu, achieving a reduction in total metal content, toxicity, mobility, and biological effectiveness, thus reducing environmental risks.

4.
Huan Jing Ke Xue ; 44(2): 730-739, 2023 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-36775597

RESUMEN

In order to explore the characteristics of exhaust gas emissions, environmental impact, and human health risks in the pesticide manufacturing industry, two typical pesticide manufacturing enterprises were selected as the research objects, and samples were collected and analyzed for all exhaust pipes of each enterprise. The following results were noted:there were certain differences in the pollutants produced by different enterprises due to different products and production links. The main pollutants in enterprise A were ammonia and VOCs. The concentration of ammonia in enterprise A ranged from 0 to 847.83 mg·m-3, and the concentration of VOCs ranged from 4.21 to 91.68 mg·m-3. The main pollutants in enterprise B were VOCs, and the concentration of VOCs ranged from 3.37 to 197.30 mg·m-3. The ozone formation potential (OFP) ranged from 1.96 to 107.24 mg·m-3. Substances that required further attention in terms of ozone formation potential:enterprise A mainly included ethanol, methanol, toluene, xylene, and other substances; enterprise B mainly included 1, 1-dichloroethylene, 1, 2-dichloroethane, toluene, methylal, and other substances. The secondary organic aerosol formation potential (SOAFP) ranged from 0.94 to 74.72 mg·m-3. The main contributors to the secondary organic aerosol formation potential were aromatic hydrocarbons and oxygen-containing organics. In addition, ammonia also required additional attention. The odorous substances in pesticide enterprises were more complex, and there were differences in the exhaust pipes of different enterprises and different production links of the same enterprise. There were certain health risks in the gas pollutants of pesticide enterprises. The main carcinogens were 1, 2-dichloroethane, trichloroethylene, tetrachloroethylene, methyl chloride, and benzene. In addition, pyridine and hexachloroethane had certain non-carcinogenic risks in pesticide production enterprises.

5.
Sensors (Basel) ; 22(19)2022 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-36236668

RESUMEN

Using a controlled optical bias and balanced geometry, we propose a new scheme for broadband terahertz detection by laser-gas interaction without high-voltage manipulation. Compared to the conventional optical bias scheme, the common noise is reduced and the dynamic range as well as the signal-to-noise ratio are doubled. It provides a simple alternative for coherent broadband terahertz detection. The influence of optical bias on terahertz waveform is also investigated, and the evolution of the terahertz-induced second harmonic with probe delay is further revealed. This new detection scheme for broadband terahertz will boost the application of terahertz time-domain spectroscopy for its miniaturization and integrability.

6.
Trials ; 23(1): 797, 2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36131289

RESUMEN

BACKGROUND: Depression and anxiety are common among pregnant women. Internet-delivered psychological therapies such as cognitive behavioral therapy (iCBT) have been developed to increase accessibility and address common help-seeking barriers, especially during pandemic period. The objective of this trial is to evaluate the short-term and long-term effects of iCBT on reducing depressive symptoms among pregnant women during the COVID-19 pandemic with the overall goal of preventing depression recurrence in the first 12 months postpartum. METHODS: A multi-site randomized controlled trial will be conducted where 300 pregnant women early in their third trimester will be screened for depression symptoms using the Edinburgh Postnatal Depression Scale (EPDS) during a routine obstetrical visit. Eligible and consenting women with a score greater than 9 will be randomly allocated (1:1) to either intervention group or control group. ICBT involving the completion of 7 weekly online modules will be delivered via a well-designed perinatal mental healthcare app. The primary objective is to evaluate the effect of iCBT on reducing depression symptoms among pregnant Chinese women starting from their third trimester. The secondary objectives are to examine the effect of iCBT on anxiety, sleep quality, social support, parenting stress, co-parenting relationship, and infant development. DISCUSSION: This multi-center randomized controlled trial has been planned in accordance with best practices in behavioral trial design. The internet-based intervention addressed the needs of pregnant women during a major pandemic where face-to-face therapy is not preferable. The trial has a relatively large sample size with sufficient power to evaluate the efficacy of iCBT intervention for the primary and secondary outcomes. One year follow-up evaluation in the study is designed to determine the longer-term effect of the intervention on both maternal and infant outcomes. Although a limitation is the assessment of depression and anxiety using self-report measures, these easily incorporated and maternal-preferred assessments allow for real-life scalability if the intervention is proven to be effective. ETHICS AND DISSEMINATION: Ethics was approved by the institutional review board of International Peace Maternity and Child Health Hospital (GKLW2020-25). Dissemination of results will be published in peer-reviewed academic journals and presented at scientific conferences. TRIAL STATUS: The first patient was enrolled on 19 August 2020. To date, 203 participants have met eligibility requirements and been randomized to either the intervention group or control group. Data collection aims to be complete in September 2022. Date and version identifier: 2020715-version1.0. TRIAL REGISTRATION: ChiCTR2000033433. Registered 31 May 2020, http://www.chictr.org.cn/showproj.aspx?proj=54482 .


Asunto(s)
COVID-19 , Terapia Cognitivo-Conductual , Niño , Terapia Cognitivo-Conductual/métodos , Depresión/diagnóstico , Depresión/terapia , Femenino , Humanos , Internet , Estudios Multicéntricos como Asunto , Pandemias , Embarazo , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
8.
PLoS One ; 17(3): e0264990, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35271640

RESUMEN

Sugarcane is a significant crop plant with the capability of accumulating higher amount of sucrose. In the present study, a high sucrose content sugarcane mutant clone, GXB9, has been studied in comparison to the low sucrose mother clone B9 on morphological, agronomical and physiological level in order to scrutinize the variation because of mutation in GXB9 in field under normal environmental condition. The results showed that GXB9 has less germination, tillering rate, stalk height, leaf length, leaf width, leaf area, number of internodes, internode length and internode diameter than B9. Qualitative traits of leaf and stalk displayed significant variation between GXB9 and B9. Endogenous hormones quantity was also showed variation between the two clones. The relative SPAD reading and chlorophyll a, b concentrations also showed variation between GXB9 and B9. The photosynthetic parameter analysis indicated that the GXB9 has significantly higher net photosynthetic rate (Pn), stomatal conductance (gs) and transpiration rate (Tr) than B9. The qRT-PCR analysis of genes encoding enzymes like SPS, SuSy, CWIN, and CeS showed upregulation in GXB9 and downregulation in B9. However, these genes were significantly differentially expressed between the immature and maturing internodes of GXB9. The cane quality trait analysis showed that GXB9 had higher juice rate, juice gravity purity, brix, juice sucrose content and cane sucrose content than B9. The yield and component investigation results indicated that GXB9 had lower single stalk weight, however higher number of millable stalks per hectare than B9, and GXB9 had lower theoretical cane yield than B9. SSR marker analysis showed genetic variation between GXB9 and B9. This study has shown significant variation in the traits of GXB9 in comparison to B9 which advocates that GXB9 is a high sugar mutant clone of B9 and an elite source for future breeding.


Asunto(s)
Saccharum , Clorofila A , Femenino , Humanos , Madres , Fitomejoramiento , Saccharum/genética , Sacarosa , Azúcares
9.
Front Vet Sci ; 8: 663956, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34222396

RESUMEN

Endometritis is the main cause of decreased reproductive performance of sows, while one of the most important factors in the etiology of sow endometritis is an aberration of birth canal microbiota. Therefore, people began to pay attention to the microbiota structure and composition of the birth canal of sows with endometritis. Interestingly, we found that the risk of endometritis was increased in the sows with constipation in clinical practice, which may imply that the intestinal flora is related to the occurrence of endometritis. Therefore, understanding the relationship between birth canal microbiota and intestinal microbiota of the host has become exceptionally crucial. In this study, the microbiota of birth canal secretions and fresh feces of four healthy and four endometritis sows were analyzed via sequencing the V3 + V4 region of bacterial 16S ribosomal (rDNA) gene. The results showed a significant difference between endometritis and healthy sows birth canal flora in composition and abundance. Firmicutes (74.36%) and Proteobacteria were the most dominant phyla in birth canal microbiota of healthy sows. However, the majority of beneficial bacteria that belonging to Firmicutes phylum (e.g., Lactobacillus and Enterococcus) declined in endometritis sow. The abundance of Porphyromonas, Clostridium sensu stricto 1, Streptococcus, Fusobacterium, Actinobacillus, and Bacteroides increased significantly in the birth canal microbiota of endometritis sows. Escherichia-Shigella and Bacteroides were the common genera in the birth canal and intestinal flora of endometritis sows. The abundance of Escherichia-Shigella and Bacteroides in the intestines of sows suffering from endometritis were significantly increased than the intestinal microbiota of the healthy sows. We speculated that some intestinal bacteria (such as Escherichia-Shigella and Bacteroides) might be bound up with the onset of sow endometritis based on intestinal microbiota analysis in sows with endometritis and healthy sows. The above results can supply a theoretical basis to research the pathogenesis of endometritis and help others understand the relationship with the microbiota of sow's birth canal and gut.

10.
Sci Total Environ ; 776: 145735, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33640544

RESUMEN

Odor emissions from intensive livestock farms have attracted increased attention due to their adverse impacts on the environment and human health. Nevertheless, a systematic summary regarding the characteristics, sampling detection, and control technology for odor emissions from livestock farms is currently lacking. This paper compares the development of odor standards in different countries and summarizes the odor emission characteristics of livestock farms. Ammonia, the most common odor substance, can reach as high as 4100 ppm in the compost area. Sampling methods for point and area source odor emissions are introduced in this paper, and odor analysis methods are compared. Olfactometers, odorometers, and the triangle odor bag method are usually used to measure odor concentration. Odor control technologies are divided into three categories: physical (activated carbon adsorption, masking, and dilution diffusion), chemical (plant extract spraying, wet scrubbing, combustion, non-thermal plasma, and photocatalytic oxidation), and biological (biofiltration, biotrickling, and bioscrubbing). Each technology is elucidated, and the performance in the removal of different pollutants is summarized. The application scopes, costs, operational stability, and secondary pollution of the technologies are compared. The generation of secondary pollution and long-term operation stability are issues that should be considered in future technological development. Lastly, a case analysis for engineering application is conducted.


Asunto(s)
Compostaje , Odorantes , Amoníaco , Animales , Granjas , Humanos , Ganado
11.
Sci Rep ; 11(1): 475, 2021 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-33436645

RESUMEN

Clostridium perfringens (Cp) is a ubiquitous opportunistic pathogen of humans and animals in the natural environment and animal intestines. The pathogenicity of Cp depends on the production of toxins encoded by genes on the chromosomes or plasmids. In contemporary literature, there is no clear consensus about the pathogenicity of CpA ß2 toxin. To analyze the homology of the genome of piglet source CpA and its ß2 toxin, we sequenced the whole genome of strain JXJA17 isolated from diarrhea piglets using the Illumina Miseq and Pacbio Sequel platforms. The genome was composed of a circular chromosome with 3,324,072 bp (G + C content: 28.51%) and nine plasmids. Genome and 16S rDNA homology analysis revealed a close relation of the JXJA17 strain with the JGS1495, Cp-06, Cp-16, and FORC_003 strains. These strains were isolated from different samples and belonged to different toxin-types. JXJA17 strain was found to carry two toxin genes (plc and cpb2). In contrast to other Cp strains, the cpb2 of JXJA17 was located on a large plasmid (58 kb) with no co-localization of other toxin genes or antibiotic resistance genes. Analysis of JXJA17 genome homology and its cpb2 would facilitate our further study the relationship between ß2 toxin and piglet diarrhea.


Asunto(s)
Toxinas Bacterianas/genética , Infecciones por Clostridium/veterinaria , Clostridium perfringens/genética , Clostridium perfringens/aislamiento & purificación , Enfermedades de los Porcinos/microbiología , Animales , China , Mapeo Cromosómico , Cromosomas , Infecciones por Clostridium/genética , Infecciones por Clostridium/microbiología , Diarrea/genética , Diarrea/microbiología , Farmacorresistencia Bacteriana/genética , Genoma Bacteriano , Plásmidos , Análisis de Secuencia de ADN , Homología de Secuencia , Porcinos , Enfermedades de los Porcinos/genética , Secuenciación Completa del Genoma
12.
Huan Jing Ke Xue ; 40(9): 3962-3972, 2019 Sep 08.
Artículo en Chino | MEDLINE | ID: mdl-31854858

RESUMEN

Odor pollution has a high complaint rate with strong public concern, and industrial production is an important source of this type of pollution in China. To understand odor pollution in industrial parks and to protect the safety of work environments, samples were collected from 14 industrial odor sources and then were analyzed for odorous volatile organic compounds (VOCs) and odor concentration. Based on the field data, the main compounds causing odor were assessed and identified. The cancer and non-cancer risk of odor exposure were correspondingly estimated by the health risk model. These following results were noted. ①The substances discharged from 14 sources were the same, but the content varied greatly. Alkanes and alkenes are the major odorous compounds of fibers and batteries manufacturing and in the synthesis of hydrocarbons, anhydrides, esters, and solvents. Benzene and benzene series in waste gases from refineries, purified terephthalic acid (PTA), and latex sources were the highest. Esters are the main pollutants emitted from activated carbon processing, resin synthesis, and spraying. Carbonyl compounds and sulfides are the main exhaust gases from ceramic manufacturing and additive synthesis. ②Exhaust gases from 14 sources caused strong irritation. The synthesis of lubricating oil additives and latex sources result in severe olfactory stimulation. Ethyl mercaptan, ethyl sulfide, n-butanol, and toluene were the major odorous compounds of lubricating oil additives sources. Styrene, propylbenzene, cumene, butyl acrylate, and 1,3-butadiene were the major odorous compounds of latex sources. ③The carcinogenic risk levels for 14 sources ranged from 3.06×10-7 to 1.06×10-2, expressed as life cancer risk (LCR). Refinery, PTA, ester, and latex sources had the highest carcinogenic risk among the 14 emission sources. The non-carcinogenic risk levels for the 14 sources ranged from 0.02 to 51.66, expressed as hazard index (HI). The total HI of latex synthesis, ester synthesis, petroleum refining, PTA synthesis, and fiber manufacturing has certain non-carcinogenic health risks. Factory boundaries for latex, anhydrides synthesis, and resin synthesis sources have potential carcinogenic risk.


Asunto(s)
Contaminantes Atmosféricos , Salud Ambiental , Contaminantes Ambientales , Odorantes , Compuestos Orgánicos Volátiles , China , Monitoreo del Ambiente , Medición de Riesgo
13.
Front Neurol ; 10: 397, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31068891

RESUMEN

Background: Significant dysbiosis occurs in the gut microbiome of stroke patients. Condensing these broad, complex changes into one index would greatly facilitate the clinical usage of gut microbiome data. Here, we formulated a gut microbiota index in patients with acute ischemic stroke based on their gut microbiota dysbiosis patterns and tested whether the index was correlated with brain injury and early outcome. Methods: A total of 104 patients with acute ischemic stroke and 90 healthy individuals were recruited, and their gut microbiotas were compared and to model a Stroke Dysbiosis Index (SDI), which representing stroke-associated dysbiosis patterns overall. Another 83 patients and 70 controls were recruited for validation. The association of SDI with stroke severity (National Institutes of Health Stroke Scale [NIHSS] score) and outcome (modified Rankin scale [mRS] score: favorable, 0-2; unfavorable, >2) at discharge was also assessed. A middle cerebral artery occlusion (MCAO) model was used in human flora-associated (HFA) animals to explore the causal relationship between gut dysbiosis and stroke outcome. Results: Eighteen genera were significantly different between stroke patients and healthy individuals. The SDI formula was devised based on these microbiome differences; SDI was significantly higher in stroke patients than in healthy controls. SDI alone discriminated stroke patients from controls with AUCs of 74.9% in the training cohort and 84.3% in the validation cohort. SDI was significantly and positively correlated with NIHSS score on admission and mRS score at discharge. Logistic regression analysis showed that SDI was an independent predictor of severe stroke (NIHSS ≥8) and early unfavorable outcome (mRS >2). Mice receiving fecal transplants from high-SDI patients developed severe brain injury with elevated IL-17+ γδ T cells in gut compared to mice receiving transplants from low-SDI patients (all P < 0.05). Conclusions: We developed an index to measure gut microbiota dysbiosis in stroke patients; this index was significantly correlated with patients' outcome and was causally related to outcome in a mouse model of stroke. Our model facilitates the potential clinical application of gut microbiota data in stroke and adds quantitative evidence linking the gut microbiota to stroke.

14.
Zhongguo Zhong Yao Za Zhi ; 43(19): 3970-3978, 2018 Oct.
Artículo en Chino | MEDLINE | ID: mdl-30453725

RESUMEN

Artesunate (AS), a famous derivative of the artemisinin, is the basic treatment globally for mild to severe malaria infection due to the prominent advantages such as high efficiency, fast effect, low toxicity and not easy to produce resistance. More and more research reports have shown that AS and its active metabolites dihydroartemisinin (DHA) had various bioactivities in addition to antimalarial activity, attracting researchers to further study its new pharmacological effects in order to explore new use of the old drug. A comprehensive understanding of the pharmacokinetic characteristics of AS will be conducive to the further development of new pharmacological actions and clinical application of AS. Therefore, this paper would review the absorption, distribution, metabolism and excretion of AS in vivo, as well as the pharmacokinetics characteristics of AS and DHA after clinical administration of AS by intravenous (IV), intramuscular (IM), oral or rectal routes. The in vivo process and pharmacokinetic parameters of AS and DHA were compared between healthy volunteers, malaria patients, and special populations (children, women). Meanwhile, the research progress on pharmacological effects of AS and active metabolite DHA such as anti-tumor, anti-inflammatory, anti septic, antiangiogenic, anti-fibrosis and immunoregulation activities would be also reviewed, hoping to provide a theoretical basis for the further development and utilization of AS and its metabolites.


Asunto(s)
Antimaláricos/farmacología , Antimaláricos/farmacocinética , Artesunato/farmacología , Artesunato/farmacocinética , Humanos , Investigación
15.
Huan Jing Ke Xue ; 39(8): 3557-3562, 2018 Aug 08.
Artículo en Chino | MEDLINE | ID: mdl-29998661

RESUMEN

To study the emission characteristics of volatile organic malodorous compounds and identify the characteristic substances of associated industries, the components of VOCs of typical industries were detected and analyzed in an industrial area of south China. The results showed that there are certain differences in the material composition among different companies, and there are also certain differences in the composition of different processes in the same company. For the automobile manufacturing industry, alcohols and esters were the main substances in the spraying workshop, accounting for 21.87% and 21.62%, respectively, and aromatic hydrocarbons were the typical substances in the drying workshop, accounting for 41.14%. Concerning the electronic components industry, esters were the main substances, accounting for 67.99% in the spraying and coating workshop. Regarding the coating production industry, esters were the main substances in the two paint companies, but the emission ratio of aromatic hydrocarbons was the second highest in one company and the emission ratio of ketone was the second highest in the other company. For the printing industry, alcohols were the characteristic substances, accounting for 99.32%. Concerning the refrigeration industry, alkanes were the most abundant compounds, accounting for 83.01%. Esters (ethyl acetate, butyl acetate, and isobutyl acetate), aromatic hydrocarbons (toluene, ethylbenzene, and styrene), and alcohol ketones (ethanol, methyl isobutyone, and 2-butanone) were preliminarily identified as characteristic malodorous compounds of the industries using organic solvents.

16.
Talanta ; 185: 411-418, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-29759220

RESUMEN

The novel quaternary ammonium modified magnetic carboxyl-carbon nanotubes (QA-Mag-CCNTs) have been synthesised and characterized. QA-Mag-CCNTs were applied in magnetic dispersive solid phase extraction (Mag-dSPE) for preconcentration of perchlorate from tea leaves prior to liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS) analysis. The Mag-dSPE procedure for preconcentration of perchlorate succeed in overcoming the flaw (containing target analyte randomly) of commercially available SPE cartridge. Under optimal conditions, the results showed higher extraction efficiency of QA-Mag-CCNTs, with recoveries between 85.2% and 107%. And the satisfactory precision with inter-day and intra-day RSD values were lower than 8.0%. Furthermore, QA-Mag-CCNTs were evaluated for reuse up to 20 times. The limit of quantification (LOQ) for perchlorate was 8.21 ng kg-1. The developed method was successfully applied in tea leaves for food-safety risk monitoring in Zhejiang province, China. The results showed the concentrations of perchlorate in 229 out of 240 collected samples were in the range of 0.082-988 µg kg-1. It was confirmed that QA-Mag-CCNTs were highly effective materials used for preconcentration of perchlorate.


Asunto(s)
Nanotubos de Carbono/química , Percloratos/análisis , Compuestos de Amonio Cuaternario/química , Té/química , Cromatografía Liquida , Campos Magnéticos , Estructura Molecular , Hojas de la Planta/química , Espectrometría de Masas en Tándem
17.
J Chromatogr A ; 1552: 1-9, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29673765

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitously found in the environment and have been proved to be prospectively associated with the risk of cancer. In this study, a simple method based on pipette-tip solid phase extraction (PT-SPE) and gas chromatography-mass spectrometry (GC-MS) has been firstly developed for the determination of 16 PAHs in human whole blood. Three-dimensional ionic liquid-ferrite functionalized graphene oxide nanocomposite (3D-IL-Fe3O4-GO) was used as sorbent in PT-SPE. Compared with conventional SPE method, the PT-SPE method was solvent-saving (1.0 mL), reusable (at least 10 times) and required less blood sample (200 µL). Affecting parameters on extraction efficiency were investigated and optimized. Under the optimized conditions, a good linearity was obtained and the recoveries of 16 PAHs at three spiked levels ranged from 85.0% to 115%. The limits of quantification (LOQs) were in the range of 0.007-0.013 µg/L. Furthermore, the developed method was successfully applied to the analysis of 16 PAHs in 14 human blood samples. The results showed that the predominant PAHs in human whole blood was low-molecular-weight PAHs, with the rank order phenanthrene (PHE)> naphthalene (NAP)> fluorene (FLU)> fluoranthene (FLT)> pyrene (PYR). Because of its simplicity, accuracy and reliability, the PT-SPE method combined with GC-MS demonstrated the applicability for clinical analysis and provided more information for PAHs exposure studies.


Asunto(s)
Compuestos Férricos/química , Grafito/química , Líquidos Iónicos/química , Nanocompuestos/química , Hidrocarburos Policíclicos Aromáticos/sangre , Extracción en Fase Sólida/métodos , Cromatografía de Gases y Espectrometría de Masas , Humanos , Límite de Detección , Óxidos/química , Hidrocarburos Policíclicos Aromáticos/química , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Reproducibilidad de los Resultados , Extracción en Fase Sólida/instrumentación
18.
Chinese Journal of Immunology ; (12): 525-530, 2018.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-702768

RESUMEN

Objective:To investigate the effects of kaempferol on the oxidized low density lipoprotein(ox-LDL)-induced injury in human umbilical vein endothelial cell (HUVECs) and to explore its underlying molecular mechanism.Methods: HUVECs were randomly divided into 6 groups:control group,ox-LDL group,Kaempferol+ox-LDL group,Kaempferol+ox-LDL+Compound C group, Kaempferol+ox-LDL+si-Nrf2 group and Kaempferol+ox-LDL+si-HO-1 group.The cell activity was measured by MTT assay.The cell apoptosis was analyzed by flow cytometry.The protein expression were measured by Western blot.The ROS levels were evaluated by flow cytometry.Results: Compared with control group,ox-LDL treatment decreased the cell viability,increased the cell apoptosis,up-regulated the protein levels of cleaved-caspase 3 and down-regulated the Bcl-2 level,elevated the expression of TNF-α,IL-1β,IL-6, vascular cell adhesion molecule (VCAM1),intercellular adhesion molecule (ICAM1) and selectin E (E-selectin),promoted the reactive oxygen species (ROS) generation and reduced the superoxide dismutase(SOD) levels,and decreased the protein levels of p-AMPK,Nrf2 and HO-1.Compared with the ox-LDL group,kaempferol treatment reversed the ox-LDL-induced cell activity inhibition, apoptosis and oxidative stress damage,and increased the protein levels of p-AMPK,Nrf2 and HO-1.Compound C,si-Nrf2 and si-HO-1 inhibited AMPK/Nrf2/HO-1 signaling pathway,elevated the production of ROS and thus inhibiting the protective effects of kaempferol on ox-LDL-treated HUVECs.Conclusion:Kaempferol alleviates ox-LDL-induced endothelial cell injury,which may be related with the activation of AMPK/Nrf2/ HO-1 signaling pathway.

19.
J Biomed Mater Res A ; 105(11): 3077-3085, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28782192

RESUMEN

Investigating the effect of four types of artificial nerve graft (ANG) structures on rat sciatic nerve defect repair will aid future ANG designs. In this study, fibroin fibers and polylactic acid were used to prepare four ANGs with differing structures: nerve conduit with micron-sized pores (Conduit with pore group), nerve conduit without micron-sized pores (Conduit group), nerve scaffold comprising Conduit with pore group material plus silk fibers (Scaffold with pore group), and nerve scaffold comprising Conduit group material plus silk fibers (Scaffold group). ANGs or autologous nerves (Autologous group) were implanted into 10 mm rat sciatic nerve defects (n = 50 per group). Twenty weeks after nerve grafting, the time required to retract the surgical limb from the hot water was ranked as follows: Conduit with pore group > Scaffold with pore group > Conduit group > Scaffold group > Autologous group. The static sciatic index was ranked in descending order: Autologous group > Scaffold group > Conduit group > Scaffold with pore group > Conduit with pore group. Immunofluorescence staining identified significant differences in the distribution and number of axons, Schwann cells, and fibroblasts. These findings indicate that ANGs with micron-sized pores had a negative impact on the repair of peripheral nerve defects, while internal microchannels were beneficial. © 2017 The Authors. Journal of Biomedical Materials Research Part A Published by Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 3077-3085, 2017.


Asunto(s)
Materiales Biocompatibles/química , Fibroínas/química , Regeneración Nerviosa , Poliésteres/química , Nervio Ciático/fisiología , Nervio Ciático/cirugía , Andamios del Tejido/química , Animales , Regeneración Tisular Dirigida/métodos , Nervios Periféricos/trasplante , Ratas , Ratas Sprague-Dawley , Nervio Ciático/lesiones , Trasplante Autólogo
20.
Biomed Pharmacother ; 88: 603-609, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28142116

RESUMEN

New chemotherapeutic compounds and regimens are needed to combat multidrug-resistant Mycobacterium tuberculosis. Here, we used a series of murine models to assess an antitubercular lead compound SKLB-TB1001. In the Mycobacterium bovis bacillus Calmette-Guérin and the acute M. tuberculosis H37Rv infection mouse models, SKLB-TB1001 significantly attenuated the mycobacterial load in lungs and spleens. The colony forming unit counts and histological examination of lungs from H37Rv infected mice revealed that the benzothiazinethione analogue SKLB-TB1001 as a higher dose level was as effective as isoniazid. Moreover, in a multidrug-resistant (MDR)-TB mouse model, SKLB-TB1001 showed significant activity in a dose-dependent manner and was more effective than streptomycin. These results suggested that SKLB-TB1001 could be an antitubercular drug candidate worth further investigation.


Asunto(s)
Antituberculosos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Tiadiazoles/farmacología , Animales , Recuento de Colonia Microbiana , Modelos Animales de Enfermedad , Femenino , Pulmón/efectos de los fármacos , Pulmón/microbiología , Pulmón/patología , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Análisis de Supervivencia , Tiadiazoles/síntesis química , Tiadiazoles/química , Tiadiazoles/uso terapéutico , Resultado del Tratamiento , Tuberculosis/tratamiento farmacológico , Tuberculosis/microbiología , Tuberculosis/patología
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