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1.
Tree Physiol ; 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31860707

RESUMO

WRKY transcription factors, one of the largest transcription factor families, play important roles in regulating the synthesis of secondary metabolites. In sweet osmanthus (Osmanthus fragrans), the monoterpenes have been demonstrated as the most important volatile compounds, and the W-box, which is the cognate binding site of WRKY transcription factors could be identified in most of terpene synthesis related genes' promoters. However, the role of the WRKY family in terpene synthesis in sweet osmanthus has rarely been examined. In this study, 154 WRKY genes with conserved WRKY domain were identified and classified into three groups. The group II was further divided into five subgroups and almost all members of IId contained a plant zinc cluster domain. Eight OfWRKYs (OfWRKY7/19/36/38/42/84/95/139) were screened from 20 OfWRKYs for their flower-specific expression patterns in different tissues. Simultaneously, the expression patterns of OfWRKYs and emission patterns of volatile compounds during the flowering process were determined and GC-MS results showed that monoterpenes, such as linalool and ocimene, accounted for the highest proportion, contributing to the floral scent of sweet osmanthus in two cultivars. In addition, correlation analysis revealed the expression patterns of OfWRKYs (OfWRKY7/19/36/139) were each correlated with distinct monoterpenes (linalool, linalool derivatives, ocimene, and ocimene derivatives). Subcellular localization analysis showed that p35S::GFP-OfWRKY7/38/95/139 were localized in the nucleus and OfWRKY139 had very strong transactivation activity. Collectively, the results indicated potential roles of OfWRKY139 and OfWRKYs with plant zinc cluster domain in regulating synthesis of aromatic compounds in sweet osmanthus, laying the foundation for use of OfWRKYs to improve aroma of ornamental plants.

2.
J Hazard Mater ; 380: 120904, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31336270

RESUMO

A hierarchical porous composite of Pt@MIL-101/ployvinylidene fluoride (Pt@MIL-101/PVDF) was successfully prepared through a solution-processed method. This composite possesses advanced superhydrophobic and superaerophilic performance which makes it a promising catalyst facilitating liquid phase catalytic exchange techniques (LPCE) in hydrogen-water isotope exchange process. Its superhydrophobic property results in the repellence of water drops from flooding the catalytic surface with a relatively large contact angle in the exchange reaction, and its superaerophilic surface broke hydrogen bubbles into thin film so as to reach higher catalytic reactive efficiency. High reactivity and long-term stability in the reaction process can also be achieved by the configuration of mesoporous cages of MIL-101 confining Pt nanoparticles and preventing them from sintering.

4.
Mol Diagn Ther ; 23(3): 395-405, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30840206

RESUMO

BACKGROUND: The clinicopathological features and genomic rearrangements of anaplastic lymphoma kinase (ALK) fusion cases have not been fully identified. OBJECTIVE: Our objective was to explore the status of ALK in non-small-cell lung cancer (NSCLC) specimens, to explore the relationships between ALK status and clinicopathological features and to identify genomic rearrangements via capture-based next-generation sequencing (NGS). METHODS: We tested 9889 NSCLC specimens for ALK status using the Ventana anti-ALK (D5F3) antibody. Clinicopathological features were analyzed and genomic rearrangements identified using capture-based NGS in 76 ALK-positive cases. RESULTS: In total, 485 specimens (4.90%) tested positive for ALK. The positivity rate was higher for adenocarcinoma samples than for non-adenocarcinoma samples (6.03 vs. 1.47%; p < 0.001) and for biopsies/cell blocks than for surgical specimens (7.00 vs. 4.16%; p < 0.001). Patient age, patient sex, specimen type, specimen histotype, and patient smoking history were all significantly correlated with ALK status. Genomic rearrangements were detected in 98.68% (75/76) of the ALK-positive samples; 89.33% (67/75) carried the canonical EML4-ALK, and the remaining samples carried only noncanonical ALK rearrangements. Four of these noncanonical ALK fusion samples were identified as carrying EML4-ALK transcripts at the RNA level. A novel fusion variant, SRD5A2-ALK, was revealed. CONCLUSIONS: Younger patients with NSCLC, especially those aged < 30 years, were more likely to test positive for ALK. Positive ALK test results were more common in patients with invasive mucinous adenocarcinoma and solid-predominant invasive adenocarcinoma than in patients with other histotypes. Samples that carried only noncanonical ALK rearrangements may also have carried the canonical EML4-ALK, which was not detected by capture-based NGS. EML4-ALK transcripts might result from rare splicing mechanisms without genomic rearrangements.

5.
BMC Cancer ; 19(1): 235, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30876389

RESUMO

BACKGROUND: Perivascular Epithelioid Cell Tumors (PEComa) is an extraordinarily rare mesenchymal neoplasm especially the malignant type originating from the lung. To date, only 8 cases of malignant or malignant potential pulmonary PEComa had been documented. Firm diagnostic criteria for malignant pulmonary PEComa need urgently to be established. CASE PRESENTATION: We report a challenging case of malignant pulmonary PEComa combined with a primary adenocarcinoma in a 54-year-old man. The PEComa-like tumor showed strong Melan-A and weak transcription factor E3 (TFE3) protein expression but no TFE3 gene rearrangement. The carcinoma-like nodule was recognized as a poorly differentiated primary lung adenocarcinoma. DISCUSSION AND CONCLUSIONS: Our case report was the first case of malignant pulmonary PEComa synchronous with a primary adenocarcinoma and studied the dilemma of diagnosing benign versus malignant criteria for this uncommon tumor.


Assuntos
Adenocarcinoma de Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Antígeno MART-1/metabolismo , Neoplasias Primárias Múltiplas/diagnóstico por imagem , Neoplasias de Células Epitelioides Perivasculares/diagnóstico por imagem , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/cirurgia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Regulação para Baixo , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/genética , Neoplasias Primárias Múltiplas/metabolismo , Neoplasias Primárias Múltiplas/cirurgia , Neoplasias de Células Epitelioides Perivasculares/genética , Neoplasias de Células Epitelioides Perivasculares/metabolismo , Neoplasias de Células Epitelioides Perivasculares/cirurgia , Procedimentos Cirúrgicos Pulmonares , Tomografia Computadorizada por Raios X , Resultado do Tratamento
6.
Hortic Res ; 5: 72, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30479779

RESUMO

Sweet osmanthus (Osmanthus fragrans) is a very popular ornamental tree species throughout Southeast Asia and USA particularly for its extremely fragrant aroma. We constructed a chromosome-level reference genome of O. fragrans to assist in studies of the evolution, genetic diversity, and molecular mechanism of aroma development. A total of over 118 Gb of polished reads was produced from HiSeq (45.1 Gb) and PacBio Sequel (73.35 Gb), giving 100× depth coverage for long reads. The combination of Illumina-short reads, PacBio-long reads, and Hi-C data produced the final chromosome quality genome of O. fragrans with a genome size of 727 Mb and a heterozygosity of 1.45 %. The genome was annotated using de novo and homology comparison and further refined with transcriptome data. The genome of O. fragrans was predicted to have 45,542 genes, of which 95.68 % were functionally annotated. Genome annotation found 49.35 % as the repetitive sequences, with long terminal repeats (LTR) being the richest (28.94 %). Genome evolution analysis indicated the evidence of whole-genome duplication 15 million years ago, which contributed to the current content of 45,242 genes. Metabolic analysis revealed that linalool, a monoterpene is the main aroma compound. Based on the genome and transcriptome, we further demonstrated the direct connection between terpene synthases (TPSs) and the rich aromatic molecules in O. fragrans. We identified three new flower-specific TPS genes, of which the expression coincided with the production of linalool. Our results suggest that the high number of TPS genes and the flower tissue- and stage-specific TPS genes expressions might drive the strong unique aroma production of O. fragrans.

7.
Pathol Res Pract ; 214(11): 1885-1891, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30268596

RESUMO

BACKGROUND: Solitary pulmonary capillary hemangioma (SPCH) is an extraordinarily rare capillary derived mesenchymal neoplasm. Although routine morphology and immunohistochemistry are adequate for the diagnosis of classical SPCH in surgical specimens, true gross appearance identification of most tumor themselves and diagnosis for some exceptional cases are still very difficult. Furthermore, preoperative imaging and frozen diagnosis remain a challenge. METHODS: We reported nine original cases of solitary pulmonary capillary hemangioma and summarized the clinical characteristics of twenty-one reported lesions. Imaging materials were reviewed by the image experts of our hospital. Quick hematoxylin-eosin stained intraoperative frozen sections and routine histological diagnosis were re-confirmed by 3 specialist pathologists with at least 10 years of diagnostic experience in our department. Immunohistochemistry analysis was performed on formalin fixed archival tissue. The surgical methods, following up information and prognosis were retrospectively analyzed. RESULTS: In imaging, three tumors showed solid nodules, three cases displayed mix ground glass nodules, two nodules were pure ground glass density, and one case was a cystic-solid mass. Macroscopically, solitary pulmonary capillary hemangiomas were ill-defined soft hemorrhagic lesion with pale yellow or dark brownish cut surface. Two cases had a clear boundary and seven lesions were poorly demarcated. Typical morphological features were densely proliferating thin-walled capillaries composing of single layer of flatten or cuboidal endothelial cells within the thickened alveolar septa. One case was mistaken for a histiocytogenic lesion during freezing. The cystic-solid lesion showed a hyperplasia capillary network along the submucosal interstitium of bronchioles. Immunohistochemically, tumor endothelial cells were positive for ERG, Fli-1, CD31, CD34 and Vimentin and negative for CK, α-SMA, TTF-1, HMB45, S-100 and CD68. Lobectomy was performed on seven cases, wedge resection and segmentectomy were proceeded in two patients respectively. Follow up information showed no evidence of complication or recurrence. CONCLUSIONS: Solitary pulmonary capillary hemangioma has special imaging and various histological features and must be distinguished from small benign lung lesions and preinvasive cancer. Although the prognosis of this tumor is good after surgical resection, the correct interpretation of the gross appearance and radiographic findings are still important. Choosing appropriate resection mode depends on accurate evaluation preoperative and intraoperative.


Assuntos
Hemangioma Capilar/diagnóstico por imagem , Hemangioma Capilar/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Adulto , Biomarcadores Tumorais/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Molecules ; 23(7)2018 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-30004428

RESUMO

Osmanthus fragrans, or "RiXiangGui", is an ornamental, woody, evergreen plant that is cultivated widely because it blooms recurrently and emits a strong fragrance. Recently, the germplasm resources, classification, and aroma compositions of O. fragrans have been investigated. However, the molecular mechanisms of the floral scent formation and regulation have remained largely unknown. To obtain a global perspective on the molecular mechanism of the aroma formation during blooming, nine RNA Sequencing (RNA-Seq) libraries were constructed from three flowering stages: The initial, full, and final flowering stage. In short, a total of 523,961,310 high-quality clean reads were assembled into 136,611unigenes, with an average sequence length of 792 bp. About 47.43% of the unigenes (64,795) could be annotated in the NCBI non-redundant protein database. A number of candidate genes were identified in the terpenoid metabolic pathways and 1327 transcription factors (TFs), which showed differential expression patterns among the floral scent formation stages, were also identified, especially OfMYB1, OfMYB6, OfWRKY1, and OfWRKY3, which could play critical roles in the floral scent formation. These results indicated that the floral scent formation of O. fragrans was a very complex process which involved a large number of TFs. This study provides reliable resources for further studies of the O.fragrans floral scent formation.


Assuntos
Oleaceae/genética , Transcriptoma/genética , Flores/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Anotação de Sequência Molecular/métodos , Proteínas de Plantas/genética , Análise de Sequência de RNA/métodos , Fatores de Transcrição/genética
9.
J Environ Sci (China) ; 69: 41-51, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29941267

RESUMO

Sulfur dioxide (SO2) and benzene homologs are frequently present in the off-gas during the process of sewage sludge drying. A laboratory scale biofilter was set up to co-treat SO2 and o-xylene in the present study. SO2 and o-xylene could be removed simultaneously in a single biofilter. Their concentration ratio in the inlet stream influenced the removal efficiencies. It is worth noting that the removal of SO2 could be enhanced when low concentrations of o-xylene were introduced into the biofilter. Pseudomonas sp., Paenibacillus sp., and Bacillus sp. were the main functional bacteria groups in the biofilter. Sulfur-oxidizing bacteria (SOB) and o-xylene-degrading bacteria (XB) thrived in the biofilter and their counts as well as their growth rate increased with the increase in amount of SO2 and o-xylene supplied. The microbial populations differed in counts and species due to the properties and components of the compounds being treated in the biofilter. The presence of mixed substrates enhanced the diversity of the microbial population. During the treatment process, bioaerosols including potentially pathogenic bacteria, e.g., Acinetobacter lwoffii and Aeromonas sp., were emitted from the biofilter. Further investigation is needed to focus on the potential hazards caused by the bioaerosols emitted from waste gas treatment bioreactors.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/metabolismo , Reatores Biológicos/microbiologia , Dióxido de Enxofre/metabolismo , Eliminação de Resíduos Líquidos/métodos , Xilenos/metabolismo , Poluentes Atmosféricos/química , Poluição do Ar/prevenção & controle , Bactérias/metabolismo , Filtração/métodos , Dióxido de Enxofre/química , Xilenos/química
10.
Inflammation ; 40(5): 1606-1621, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28634844

RESUMO

Thrombospondin-1 (TSP-1) is upregulated in several inflammatory diseases. Recent data have shown that macrophages from TSP-1-deficient mice have a reduced inflammatory phenotype, suggesting that TSP-1 plays a part in macrophage activation. DNA microarray approach revealed that Porphyromonas gingivalis lipopolysaccharide (P. gingivalis LPS) may induce the enhanced TSP-1 expression in human monocytes, suggesting a role of TSP-1-mediated pathogenesis in periodontitis. Until recently, the function of TSP-1 has been a matter of debate. In this study, we explored the role of TSP-1 in inflammatory cytokine secretions and its putative mechanism in pathogenesis of periodontitis. We demonstrated that TSP-1 expression was significantly upregulated in gingival tissues with periodontitis and in P. gingivalis LPS-stimulated THP-1 cells. Deficiency of TSP-1 by transfecting siRNAs decreased IL-6, IL-1ß, and TNF-α secretions in THP-1 cells, whereas overexpression of TSP-1 resulted in an upregulation of IL-6, IL-1ß, and TNF-α productions. Additional experiments showed that Pyrrolidine dithiocarbamate (PDTC) inhibited IL-6, IL-1ß, and TNF-α expression induced by overexpression of TSP-1, accompanying with downregulation of phosphorylated p65 and IκBα protein levels in response to P. gingivalis LPS. These results indicated that TSP-1 played a significant role in P. gingivalis LPS-initiated inflammatory cytokines (IL-6, IL-1ß, and TNF-α) secretions of THP-1 cells, and the NF-κB signaling is involved in its induction of expression. Thus, TSP-1 effectively elevated P. gingivalis LPS-induced inflammation mediated by the NF-κB pathway and may be critical for pathology of periodontitis.


Assuntos
Citocinas/metabolismo , Inflamação/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Trombospondina 1/fisiologia , Humanos , Inflamação/induzido quimicamente , Lipopolissacarídeos , Periodontite/etiologia , Periodontite/microbiologia , Periodontite/patologia , Porphyromonas gingivalis/patogenicidade , Células THP-1 , Trombospondina 1/biossíntese , Trombospondina 1/farmacologia
11.
Huan Jing Ke Xue ; 37(2): 782-8, 2016 Feb 15.
Artigo em Chinês | MEDLINE | ID: mdl-27363173

RESUMO

Co-processing of sewage sludge using the cement kiln can realize sludge harmless treatment, quantity reduction, stabilization and reutilization. The moisture content should be reduced to below 30% to meet the requirement of combustion. Thermal drying is an effective way for sludge desiccation. Odors and volatile organic compounds are generated and released during the sludge drying process, which could lead to odor pollution. The main odor pollutants were selected by the multi-index integrated assessment method. The concentration, olfactory threshold, threshold limit value, smell security level and saturated vapor pressure were considered as indexes based on the related regulations in China and foreign countries. Taking the pollution potential as the evaluation target, and the risk index and odor emission intensity as evaluation indexes, the odor pollution potential rated evaluation model of the pollutants was built according to the Weber-Fechner law. The aim of the present study is to form the rating evaluation method of odor potential pollution capacity suitable for the directly drying process of sludge.


Assuntos
Dessecação , Odorantes/análise , Eliminação de Resíduos/métodos , Esgotos/análise , China , Compostos Orgânicos Voláteis/análise
12.
J Environ Sci (China) ; 37: 130-8, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26574096

RESUMO

Sulfide dioxide (SO2) is often released during the combustion processes of fossil fuels. An integrated bioreactor with two sections, namely, a suspended zone (SZ) and immobilized zone (IZ), was applied to treat SO2 for 6months. Sampling ports were set in both sections to investigate the performance and microbial characteristics of the integrated bioreactor. SO2 was effectively removed by the synergistic effect of the SZ and IZ, and more than 85% removal efficiency was achieved at steady state. The average elimination capacity of SO2 in the bioreactor was 2.80g/(m(3)·hr) for the SZ and 1.50g/(m(3)·hr) for the IZ. Most SO2 was eliminated in the SZ. The liquid level of the SZ and the water content ratio of the packing material in the IZ affected SO2 removal efficiency. The SZ served a key function not only in SO2 elimination, but also in moisture maintenance for the IZ. The desired water content in IZ could be feasibly maintained without any additional pre-humidification facilities. Clone libraries of 16S rDNA directly amplified from the DNA of each sample were constructed and sequenced to analyze the community composition and diversity in the individual zones. The desulfurization bacteria dominated both zones. Paenibacillus sp. was present in both zones, whereas Ralstonia sp. existed only in the SZ. The transfer of SO2 to the SZ involved dissolution in the nutrient solution and biodegradation by the sulfur-oxidizing bacteria. This work presents a potential biological treatment method for waste gases containing hydrophilic compounds.


Assuntos
Poluentes Atmosféricos/isolamento & purificação , Poluentes Atmosféricos/metabolismo , Bactérias/metabolismo , Reatores Biológicos/microbiologia , Dióxido de Enxofre/isolamento & purificação , Dióxido de Enxofre/metabolismo , Poluentes Atmosféricos/química , Bactérias/classificação , Biomassa , Interações Hidrofóbicas e Hidrofílicas , Dióxido de Enxofre/química , Água/química
13.
Water Sci Technol ; 72(4): 543-52, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26247752

RESUMO

Sludge drying is a necessary step for sludge disposal. In this study, sludge was collected from two wastewater treatment plants, and dried at different temperatures in the laboratory. The emission of odor and total volatile organic compounds (TVOCs) during the sludge drying process were determined by an online odor monitoring system. The volatile organic compounds (VOCs) in off-gas were analyzed by gas chromatography-mass spectrometry. Results showed that sludge with 30% moisture content could be obtained in 51 minutes under drying temperature 100 °C but only within 27 minutes under 150 °C. Concentration of odor, TVOCs, sulfur-containing compounds (SCCs), and amines were changed with drying temperature and sludge sources. The maximum concentration of odor, TVOCs, SCCs, and amines were 503.13 ppm, 3.01 ppm, 8.15 ppm, and 11.27 ppm, respectively, at drying temperature 100 °C. These values reached 1,250.79, 8.10, 53.51, and 37.80 ppm when sludge dried at 150 °C. Odor concentration had a close relationship with emission of SCCs, amines, and TVOCs. The main VOCs released were benzene series and organic acid. Potential migration of substances in sludge was examined via analysis of off-gas and condensate, aiming to provide scientific data for effective sludge treatment and off-gas control.


Assuntos
Poluentes Atmosféricos/análise , Aminas/análise , Odorantes/análise , Esgotos/análise , Compostos de Enxofre/análise , Compostos Orgânicos Voláteis/análise , Dessecação , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Ambiente , Eliminação de Resíduos Líquidos , Águas Residuárias/análise
14.
J Anal Methods Chem ; 2015: 163163, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26167333

RESUMO

In order to reveal the influence of the metals of soil-water interface in a manganese mine (Xiangtan, China), on local water environment, there are six kinds of metals (Mn, Ni, Cu, Zn, Cd, and Pb) characterized by measuring their concentration, correlation, source, and special distribution using principal component analysis, single factor, and Nemero comprehensive pollution index. The results showed that the corresponding average concentration was 0.3358, 0.045, 0.0105, 0.0148, 0.0067, and 0.0389 mg/L. The logarithmic concentration of Mn, Zn, and Pb was normal distribution. The correlation coefficients (between Mn and Pb, Mn and Zn, Mn and Ni, Cu and Zn, Cu and Pb, and Zn and Cd) were found to range from 0.5 to 0.6, and those between Cu and Ni and Cu and Cd were below 0.3. It was found that Zn and Mn pollution were caused primarily by ore mining, mineral waste transportation, tailing slag, and smelting plants, while Cu and Ni mainly originate from the mining industry activities and the traffic transportation in the mining area. In addition, the Cd was considered to be produced primarily from the agricultural or anthropogenic activities. The pollution indexes indicated that metal pollution degree was different in soil-water interface streams as listed in increasing order of pollution level as Zn > Ni > Cu > Pb > Mn > Cd. For all of the pollution of the soil-water interface streams, there was moderate metal pollution but along the eastern mine area the pollution seemed to get more serious. There was only a small amount of soil-water interface streams not contaminated by the metals.

15.
Huan Jing Ke Xue ; 35(8): 2897-902, 2014 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-25338358

RESUMO

Co-processing sewage sludge by using the high-temperature feature of cement kiln can realize harmless disposal and energy recycling. In this paper, investigation on characteristics of the flue gas from sludge drying process was carried out in Guangzhou Heidelberg Yuexiu Cement Co., LTD. The composition and the main source of odors and volatile organic compounds (VOCs) emitted during the drying process were analyzed, aimed to provide scientific basis for the treatment of sewage sludge. Results showed that there were a large number of malodorous substances and VOCs in the flue gas. Sulfur dioxide and other sulfur-containing compounds were the main components in the malodorous substances, while benzene derivatives were predominant in VOCs. The compositions of odors and VOCs were influenced by the characteristics of the sludge and the heat medium (kiln tail gas). Total organic compounds in the sludge were significantly decreased after drying. Other organic substances such as volatile fatty acid, protein, and polysaccharide were also obviously reduced. The organic matter in sludge was the main source of VOCs in the flue gas. Part of sulfurous substances, such as sulfur dioxide, carbon disulfide, were from sulfur-containing substances in the sludge, and the rest were from the kiln tail gas itself.


Assuntos
Odorantes/análise , Esgotos/análise , Compostos Orgânicos Voláteis/análise , Eliminação de Resíduos Líquidos/métodos , Dessecação , Ácidos Graxos Voláteis/análise , Compostos de Enxofre/análise , Dióxido de Enxofre/análise
16.
J Environ Sci (China) ; 26(8): 1575-83, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25108713

RESUMO

Bioaerosols from wastewater treatment processes are a significant subgroup of atmospheric aerosols. In the present study, airborne microorganisms generated from a wastewater treatment station (WWTS) that uses an oxidation ditch process were diminished by ventilation. Conventional sampling and detection methods combined with cloning/sequencing techniques were applied to determine the groups, concentrations, size distributions, and species diversity of airborne microorganisms before and after ventilation. There were 3021 ± 537 CFU/m³ of airborne bacteria and 926 ± 132 CFU/m³ of airborne fungi present in the WWTS bioaerosol. Results showed that the ventilation reduced airborne microorganisms significantly compared to the air in the WWTS. Over 60% of airborne bacteria and airborne fungi could be reduced after 4 hr of air exchange. The highest removal (92.1% for airborne bacteria and 89.1% for fungi) was achieved for 0.65-1.1 µm sized particles. The bioaerosol particles over 4.7 µm were also reduced effectively. Large particles tended to be lost by gravitational settling and small particles were generally carried away, which led to the relatively easy reduction of bioaerosol particles 0.65-1.1 µm and over 4.7 µm in size. An obvious variation occurred in the structure of the bacterial communities when ventilation was applied to control the airborne microorganisms in enclosed spaces.


Assuntos
Microbiologia do Ar , Bactérias/isolamento & purificação , Ventilação , Eliminação de Resíduos Líquidos/métodos , Aerossóis/química , Bactérias/classificação , Bactérias/genética , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Filogeografia , Fatores de Tempo , Instalações de Eliminação de Resíduos
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