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1.
J Nanosci Nanotechnol ; 20(3): 1613-1621, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492323

RESUMO

Nano-composite films were developed between silver nanoparticles (Ag NPs) and a low-density polyethylene (LDPE) using master batches by melt extruding and melt compounding. The Ag/PE composite film showed decreased gas permeability, moisture permeability coefficient, the tear strength, the longitudinal and transverse elongation to that of commercial LDPE. Although stiffness increased at high Ag (40 ppm) concentration, but the longitudinal and transverse tensile strength enhance comparing with commercial PE. Light transmittance and haze were comparable. Both Nano-silver and composite films are effective against Escherichia coli (E. coli). Antibacterial activity of nano-silver for E. coli was determined by diameter of the inhibition zone and the minimum inhibitory concentration of nano-silver is detected by tube double dilution method reaching 15.63 ppm. The composite films are effective inhibition of E. coli at concentrations of 40 ppm Ag nanoparticles. Moreover, Nano-silver migration occurs in composite film. One-side migration was conducted to detect under three food simulants (3% acetic acid, 50% ethanol and distilled water) at three degree of temperature (25 °C, 40 °C and 70 °C) on different period of time (2, 4, 6, 8, 10 and 12 hours). These results indicated that the highest migration amount was obtained with 3% acetic acid following distilled water and finally 50% ethanol under same conditions. The migration level is dependent upon time and temperature and high migration time and temperature can enhance migration level. These findings demonstrate that nano-silver-containing polyethylene composite film may have a great potential for developing antibacterial and acid food packaging system.

2.
J Nanosci Nanotechnol ; 20(2): 673-679, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383062

RESUMO

A proper soft tissue seal between implants and gingiva is critical for success of dental implants. Implant surface modification is an important approach for achieving ideal host-implant integration. In this study, we used a new and simple oxidation method to generate a rough surface on implants at the nano scale, which oxidized titanium nano-foveolae (TiNF) surface. We further analyzed the surface topography and tested its effects on biological activities of human gingival fibroblasts. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) examination demonstrated that TiNF disks displayed uniform rough surfaces, with average TiNF diameters of approximately 60 nm and 100 nm respectively. However, the surfaces of smooth samples were highly irregular, and cell adhesion and proliferation rates on TiNF surfaces were significantly higher than those of the smooth surfaces. Extracellular matrix synthesis was also increased in the cells that interacted with oxidized TiNF surfaces. Altogether, these results suggest that the TiNF implant surfaces perform better for human gingival fibroblast biological activities compared to traditional smooth surfaces. Therefore, the TiNF implant surfaces may serve as ideal interface to facilitate implant-host integration.

3.
RNA Biol ; : 1-12, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31402756

RESUMO

One key to malignant progression of pancreatic cancer (PC) is the acquired ability of tumour cells to escape immune-mediated lysis. Hypoxic microenvironment plays a causal role in PC metastasis. According to previous studies, hypoxia could induce the upregulation of HIF1A, ADAM10 and sMICA, leading to decreased NKG2D in NK cells and tumour cells escape from immune surveillance and NK cell-mediated lysis. In the present study, in NK cells derived from high-HIF1A expression patients, the levels of internalization of MICA/B and NKG2D were obviously higher than those in low-HIF1A expression group; hypoxia dramatically upregulated the levels of sMICA culture supernatant of Panc-1 cells. Regarding the molecular mechanism, dysregulated circRNAs and miRNAs that might modulate HIF1A-mediated immune escape were selected and examined for detailed functions. The expression of circ_0000977 could be induced by hypoxia, and circ_0000977 knockdown enhanced the killing effect of NK cells on PC cells under hypoxia through HIF1A and ADAM10. HIF1 and ADAM10 were direct downstream targets of miR-153; circ_0000977 served as a sponge for miR-153 to counteract miR-153-mediated repression of HIF1 and ADAM10 mRNA through direct targeting in both 293T cells and Panc-1 cells. miR-153 inhibition exerted an opposing effect on HIF1A-mediated immune escape of PC cells to circ_0000977 knockdown; the effect of circ_0000977 knockdown were partially attenuated by miR-153 inhibition. In summary, circ_0000977/miR-153 axis modulates HIF1A-mediated immune escape of PC cells through miR-153 downstream targets HIF1A and ADAM10. We provided a novel mechanism of HIF1A-mediated immune escape of PC cells from the perspective of circRNAs-miRNA-mRNA axis. Abbreviations: Pancreatic cancer (PC); peripheral blood lymphocytes (PBLs); A Disintegrin and Metalloproteinase Domain 10 (ADAM10); MHC class I-related molecule A (MICA); soluble MICA (sMICA); membrane MICA (mMICA); Hypoxia-inducible factor 1-alpha (HI1FA); long non-coding RNAs (lncRNAs); non-coding RNAs (ncRNAs); natural killer (NK); Haematoxylin and eosin (H&E); Immunohistochemistry (IHC); natural killer group 2 member D (NKG2D).

4.
J Craniofac Surg ; 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31449217

RESUMO

Maxillary hypoplasia is a common developmental deformity affecting patients with cleft lip and palate. Various surgical techniques including conventional orthognathic surgery, total maxillary distraction osteogenesis, and anterior maxillary segmental distraction have been applied to address the deformity. With the evolution of 3D computed tomography imaging, the visualization of skeletal complexities in different perspectives is greatly enhanced and comprehensive surgical planning is achieved. Intraoperative efficiency is also improved with the fabrication of 3D-printed templates. The study aims to present different surgical techniques with virtual surgical planning (VSP) and 3D-printed surgical templates and the solution of representative cases. From January 2014 to January 2019, VSP was transferred to actual surgery or distraction precisely in 80 adult patients with cleft-related maxillary hypoplasia. The accuracy was analyzed and the relapse was also estimated and observed in 18 patients after 1-year follow-up. Based on our experience, VSP provides a more reliable and effective option to conventional model surgery. It facilitates the preoperative planning and accurately transfers the virtual plan to correct the cleft-related maxillary hypoplasia.

5.
Ying Yong Sheng Tai Xue Bao ; 30(8): 2682-2690, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418193

RESUMO

Based on the field investigation data and the integration GIS spatial methods and geographical detector model, we analyzed the main and interactive effects of geographical and social environmental factors on the distribution of invasive plants in Fujian Province, China. The results showed that a total of 82 invasive plant species were recorded, with Compositae as the dominant family. Conyza canadensis, Ageratum conyzoides, and Alternanthera philoxeroides had the highest frequencies. There were more invasive species in coastal areas than in inland areas. Fuzhou and Xiamen were the hot areas for plant invaision. The invasive plants widely distributed at different altitudes, and the invasion reduced with the increasing altitude. The geographical detector analysis showed that rainfall as a natural environment factor and road density and people density as socio-economy factors were the major driving factors for the distribution of invasive plant species. The multi-factor interaction had a positive effect on the spatial distribution of invasive plants, implying the complexity of impact factors on the distribution of invasive plant species. In conclusion, the geographical detector could be used in the studies of invasive plants, and environmental factors could be also applied for monitoring the suitable establishment areas of invasive plants in Fujian Province. Our results provide a scientific basis for effective management of invasive plants.


Assuntos
Espécies Introduzidas , Plantas , Altitude , China , Geografia
6.
Medicine (Baltimore) ; 98(26): e16146, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31261541

RESUMO

Foreign bodies impaction in the esophagus is a common clinical emergency. The aim of this study was to investigate the clinical features of foreign body ingestion, and to analyze the risk factors of complications during the endoscopic procedure.From 18 general hospitals in Zhejiang Province in China, 595 patients who underwent gastroscopic removal of ingested foreign bodies were prospectively recruited. Patient characteristics, clinical features, foreign body features, clinical outcomes, and complications were documented.The most common types of foreign body in the esophagus were sharp objects (75.9%), including fish bones (34.0%), chicken bones (22.1%), and fruit nuclei (17.1%). The remaining types were non-sharp objects (24.1%), including food bolus (14.6%). Most objects were lodged in the proximal esophagus (75.9%). Foreign body-related complications occurred in 63 patients (10.5%), including hemorrhage (5.0%), perforation and infection (5.5%). The complication rate was increased by 4.04- and 8.48- fold when endoscopic retrieval was performed after impacted for over 24 and 48 hours, respectively, after impaction, as compared with within 12 hours. Logistic regression analysis revealed that the patients with sharp objects developed more complications than those with non-sharp ones (odds ratio, 2.85; 95% confidence interval, 1.08-7.50; P = .034). However, complications were unrelated with the location in the esophagus or length of foreign bodies (P > .05).Sharp objects were the most frequently ingested foreign bodies in the esophagus in China. The prevalence of complications was increased in the patients with long foreign body retention time (>24 hours) and sharp objects. Sharp foreign bodies in the esophagus are recommended to be removed within 24 hours.


Assuntos
Esofagoscopia , Esôfago/cirurgia , Corpos Estranhos/cirurgia , Complicações Pós-Operatórias/epidemiologia , Adolescente , Adulto , China , Esôfago/diagnóstico por imagem , Esôfago/lesões , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Tempo para o Tratamento , Adulto Jovem
7.
J Integr Plant Biol ; 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31305005

RESUMO

Rejuvenation refers to the process enabling plants to regain physiological and molecular characteristics lost after entering the adult phase. The underlying molecular mechanism is poorly understood. Previous studies have revealed that microRNA156 (miR156) is highly accumulated at juvenile stage and maintains juvenile traits by repressing a group of SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors. Here, we found that induction of miR156 expression in adult leaves can only restore some aspects of juvenile traits, such as loss of epidermal leaf hairs on the lower side of leaves and absence of serration at the leaf edges, but is incapable of delaying flowering and promoting adventitious root production.

8.
Microb Cell Fact ; 18(1): 111, 2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31200722

RESUMO

BACKGROUND: Bacillus subtilis is developed to be an attractive expression host to produce both secreted and cytoplasmic proteins owing to its prominent biological characteristics. Chromosomal integration is a stable expression strategy while the expression level is not ideal compared with plasmid expression. Thus, to meet the requirement of protein overexpression, promoter, as one of the key elements, is important. It is necessary to obtain an ideal promoter for overproduction of foreign proteins from a single copy expression cassette. RESULTS: The activity of promoter Pylb was further enhanced by optimizing the - 35, - 10 core region and upstream sequence (UP) by substituting both sequences with consensus sequences. The final engineered promoter exhibited almost 26-fold in ß-galactosidase (BgaB) activity and 195-fold in super-folded green fluorescent protein (sfGFP) intensity than that of WT. The two proteins account for 43% and 30% of intracellular proteins, respectively. The promoter was eventually tested by successful extracellular overproduction of Methyl Parathion Hydrolase (MPH) and Chlorothalonil hydrolytic dehalogenase (Chd) to a level of 0.3 g/L (144 U/mL) and 0.27 g/L (4.4 U/mL) on shake-flask culture condition. CONCLUSIONS: A strong promoter was engineered for efficient chromosomally integrated expression of heterologous proteins.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31087229

RESUMO

An effective and powerful regulation is indispensable for the development and smooth operation of a cap-and-trade emission trading scheme (ETS). Seven regional pilot ETSs have been established and gradually improved in China, from which the experiences and lessons learned may provide useful references to facilitate China's national ETS regulation. This article systematically reviews and compares the practices and policies of carbon trading regulation in China's seven pilot schemes from three major aspects of regulatory institutions and subjects, regulatory objects and content, and regulatory means and techniques, and covering both internal and external regulatory architectures. The comparative analysis has demonstrated that the regional pilot schemes have made notable achievements in developing ETS regulatory systems with Chinese characteristics, but they still have considerable deficiencies. Referencing both international and domestic pilot experiences, this study recommends that China's national ETS improve regulatory institutional basis, foster an extensive participation of pluralistic regulatory subjects with a clear division of powers and responsibilities, establish effective regulatory systems on carbon finance, and continuously enrich regulatory techniques and platforms.

10.
J Nanosci Nanotechnol ; 19(10): 6328-6333, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31026956

RESUMO

We investigated the optical and electrical properties of a ß-Ga2O3/Ag/ß-Ga2O3 multilayer transparent conductive electrode deposited on an α-Al2O3 (0001) substrate. For the deposition of a continuous Ag layer, we preliminarily performed anultraviolet-ozone pretreatment of the Ga2O3 bottom layer. To obtain a stable ß-phase of Ga2O3, the ß-Ga2O3/Ag/ß-Ga2O3 multilayer was annealed at 700 °C under N2 atmosphere. The transmittance and sheet resistance of the ß-Ga2O3/Ag/ß-Ga2O3 multilayer were critically affected by the surface morphology and thickness of the Ag interlayer. The multilayer with optimized thicknesses (ß-Ga2O3 top layer: 30 nm; Ag interlayer: 12 nm; ß-Ga2O3 bottom layer: 60 nm) exhibited a resistance of 8.48 Ωsq-1, an average optical transmittance of 87.16% in the ultraviolet wavelength range from 300 to 350 nm, and a figure of merit of 29.81 × 10-3 Ω-1.

11.
Sci Rep ; 9(1): 6223, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30996240

RESUMO

Phylogenetic incongruence has frequently been encountered among different molecular markers. Recent progress in molecular phylogenomics has provided detailed and important information for evolutionary biology and taxonomy. Here we focused on the freshwater viviparid snails (Cipangopaludina chinensis chinensis and C. c. laeta) of East Asia. We conducted phylogenetic analyses and divergence time estimation using two mitochondrial markers. We also performed population genetic analyses using genome-wide SNPs. We investigated how and which phylogenetic patterns reflect shell morphology. The results showed these two species could be separated into four major mitochondrial clades, whereas the nuclear clusters supported two groups. The phylogenetic patterns of both mtDNA and nDNA largely reflected the geographical distribution. Shell morphology reflected the phylogenetic clusters based on nDNA. The findings also showed these two species diversified in the Pliocene to early Pleistocene era, and occurred introgressive hybridisation. The results also raise the taxonomic issue of the two species.

12.
Biotechnol Bioeng ; 116(8): 2052-2060, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30989640

RESUMO

Although one of the major factors limiting the application of Bacillus subtilis as an expression host has been its production of at least eight extracellular proteases, researchers have also noticed that some proteases benefited the secretion of foreign proteins at times. Therefore, to maximize the yield of a foreign protein, the proteases should be selectively inactivated. This raises a new question that how to identify the favorable and unfavorable proteases for a target protein. Here, an evaluation system containing nine mutant strains of B. subtilis 168 was developed to address this question. The mutant strain PD8 has all the eight proteases inactivated whereas each of the other eight mutant strains expresses only one kind of these eight proteases. The target protein is secreted in these nine mutant strains; if the production of target protein in a mutant strain is higher than that in strain PD8, the corresponding protease is regarded as favorable. Accordingly, the optimal protease-deficient host is constructed through inactivating the unfavorable proteases. The effectiveness of this system was confirmed by expressing three foreign proteins. This study provides a strategy for improving the secretion of a foreign protein in B. subtilis through tailoring a personalized protease-deficient host.

13.
BMC Cancer ; 19(1): 279, 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30922248

RESUMO

BACKGROUND: With poor prognosis and limited treatment options for advanced hepatocellular carcinoma (HCC), development of novel therapeutic agents is urgently needed. This single-arm phase I study sought to assess the safety and preliminary efficacy of icaritin in human as a potential oral immunotherapy in addition to the immune-checkpoint inhibitors. METHODS: Eligible advanced HCC patients with Child-Pugh Class A or B were administered with a fixed oral dose of icaritin at either 600 or 800 mg b.i.d. The primary endpoint was safety, and the secondary endpoints included time-to-progression (TTP), overall survival (OS) and the clinical benefit rate (CBR). Icaritin treatment induced immune biomarkers and immune-modulating activities in myeloid cells were also explored. RESULTS: No drug-related adverse events ≥ Grade 3 were observed in all 20 enrolled HCC patients. Among the 15 evaluable patients, 7 (46.7%) achieved clinical benefit, representing one partial response (PR, 6.7%) and 6 stable disease (SD, 40%). The median TTP was 141 days (range: 20-343 days), and the median OS was 192 days (range: 33-1036 days). Durable survival was observed in PR/SD patients with a median OS of 488 days (range: 72-773). TTP was significantly associated with the dynamic changes of peripheral neutrophils (p = 0.0067) and lymphocytes (p = 0.0337). Icaritin treatment induced changes in immune biomarkers-and immune-suppressive myeloid cells were observed. CONCLUSIONS: Icaritin demonstrated safety profiles and preliminary durable survival benefits in advanced HCC patients, which were correlated with its immune-modulation activities and immune biomarkers. These results suggested the potential of icaritin as a novel oral immunotherapy for advanced HCC in addition to antibody-based PD-1/PD-L1 blockade therapies. TRIAL REGISTRATION: Clinicaltrial.gov identifier. NCT02496949 (retrospectively registered, July 14, 2015).


Assuntos
Biomarcadores Tumorais/imunologia , Carcinoma Hepatocelular/tratamento farmacológico , Flavonoides/administração & dosagem , Neoplasias Hepáticas/tratamento farmacológico , Administração Oral , Adulto , Idoso , Carcinoma Hepatocelular/imunologia , Esquema de Medicação , Feminino , Flavonoides/efeitos adversos , Flavonoides/farmacologia , Humanos , Neoplasias Hepáticas/imunologia , Linfócitos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Neutrófilos/efeitos dos fármacos , Análise de Sobrevida , Resultado do Tratamento
14.
Artigo em Inglês | MEDLINE | ID: mdl-30761418

RESUMO

The questions of how to mitigate climate change and its impact on human health are currently high on the Chinese agenda for future development. The emission trading scheme (ETS) has become one of China's most important instruments to address climate change through a market mechanism. In the wake of the evolution from regional pilots to a nationwide scheme, it is inevitable to be confronted with tremendous political-economic-institutional challenges. To facilitate a smooth start-up of the upcoming nationwide ETS, this study provides a systematic overview of seven ETS pilots, involving the detailed comparison of ETS design and the in-depth evaluation of market performance, both internal and external performance, based on trading data. Then, the achievements and deficiencies of seven ETS pilots are summarized, several challenges for the current time are discussed, and policy proposals for China's national-level ETS are navigated further coupled with international experience. This study finds that China's ETS pilots, from the short-term perspective, are successful, especially in the reinforcement of China's capacity to develop a market-based scheme in an economy that still cherishes many non-market endowments. However, deficiencies lie in both the internal and external market performance, such as the carbon price lacking a signal function, insufficient incentives for compliance, too low market liquidity, and much too high market fragmentation. Moreover, the retrospective examination of China's ETS pilots suggests that a nationwide ETS should at least be based on an extension of the cap duration from single year to several years, uniform rules on monitoring/reporting/verification and allowance allocation, and the improvement of institutional foundation.

15.
Autophagy ; 15(6): 998-1016, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30706760

RESUMO

Macroautophagy/autophagy dysfunction is associated with many neurodegenerative diseases. TFEB (transcription factor EB), an important molecule that regulates lysosomal and autophagy function, is regarded as a potential target for treating some neurodegenerative diseases. However, the relationship between autophagy dysfunction and spiral ganglion neuron (SGN) degeneration and the role of TFEB in SGN degeneration has not yet been established. Here, we showed that in degenerated SGNs, induced by sensory epithelial cell loss in the cochlea of mice following kanamycin and furosemide administration, the lipofuscin area and oxidative stress level were increased, the nuclear-to-cytoplasmic TFEB ratio was decreased, and the late stage of autophagic flux was impaired. After autophagy dysfunction was partially ameliorated with an MTOR inhibitor, which promoted TFEB translocation into the nucleus from the cytoplasm, we found that the lysosomal deficits were significantly relieved, the oxidative stress level was reduced, and the density of surviving SGNs and auditory nerve fibers was increased. The results in the present study reveal that autophagy dysfunction is an important component of SGN degeneration, and TFEB may be a potential target for attenuating SGN degeneration following sensory epithelial cell loss in the cochlea of mice. Abbreviations: 3-NT: 3-nitrotyrosine; 4-HNE: 4-hydroxynonenal; 8-OHdG: 8-hydroxy-2'-deoxyguanosine; ABR: auditory brainstem response; APP: amyloid beta (A4) precursor protein; CLEAR: coordinated lysosomal expression and regulation; CTSB: cathespin B; CTSD: cathespin D; SAMR1: senescence-accelerated mouse/resistance 1; SAMP8: senescence-accelerated mouse/prone 8; MAPK1/ERK2: mitogen-activated protein kinase 1; MTOR: mechanistic target of rapamycin kinase; SGN: spiral ganglion neuron; SQSTM1/p62: sequestosome 1; TEM: transmission electron microscope; TFEB: transcription factor EB.

16.
Cryobiology ; 86: 47-51, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30597125

RESUMO

Devitrification has been determined to be one of the major causes of cell death in cryopreservation by vitrification method. Reliable quantification of the nucleation and growth of ice crystals of devitrification is of great importance for the optimization of the vitrification solutions. In the present study, cryomicroscopy was used to investigate the nucleation and growth of ice crystals in concentrated glycerol aqueous solution (60 wt%) in the presence of sucrose, trehalose, maltose and lactose. Results showed that sucrose rather than trehalose seems to be the most effective one to inhibit the nucleation and ice growth, despite the excellent inhibitory ability of trehalose on ice growth that has been confirmed in many researches. Hence, for ice inhibition, sucrose was a more effective disaccharide additive to suppress nucleation and growth of ice crystals that occurred during devitrification in concentrated glycerol solutions.

17.
J Cell Physiol ; 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30693518

RESUMO

Nowadays, pancreatic cancer (PC) remains the most lethal tumor, partially due to the invasive and treatment-resistant phenotype induced by the extent of hypoxic stress within the tumor tissue. According to previous studies, miR-142/HIF-1α and miR-133a/EGFR could modulate PC cell proliferation under hypoxic and normoxic conditions, respectively. In the present study, FEZF1-AS1, a recently described oncogenic long noncoding RNA, was predicted to target both miR-142 and miR-133a; thus, we hypothesized that FEZF1-AS1 might affect PC cell proliferation through these two axes under hypoxic or normoxic conditions. In PC cell lines, FEZF1-AS1 acted as an oncogene via promoting PC cell proliferation and invasion through miR-142/HIF-1α axis under hypoxic condition; however, FEZF1-AS1 failed to affect the protein levels of HIF-1α and VEGF under the normoxic condition, suggesting the existence of another signaling pathway under normoxic condition. As predicted by an online tool, FEZF1-AS1 could target miR-133a to inhibit its expression; under the normoxic condition, FEZF1-AS1 exerted its effect on PC cell lines through miR-133a/EGFR axis. Taken together, FEZF1-AS1 might be a promising target in controlling the aberrant proliferation and invasion of PC cell lines.

18.
Environ Geochem Health ; 41(3): 1545-1557, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30604306

RESUMO

Chlorine dioxide (ClO2) has been widely used in the process of preoxidation and disinfection as an excellent water treatment reagent. However, the inorganic by-products produced by ClO2, such as chlorite (ClO2-) and chlorate (ClO3-) are harmful to human health, and this has become a potential problem when using ClO2 in drinking water treatment. In this study, ClO2 alone and a ClO2/NaClO combination process were carried out to evaluate the algae removal efficiency of the treatment and the formation of disinfection by-products (DBPs: chlorite, chlorate, trihalomethanes and haloacetic acids) for high algae-laden water with 124.16 µg L-1 chlorophyll a (Chl.a) content. The results show that disinfection with 1.5 mg L-1 ClO2 alone results in a ClO2- concentration exceeding 0.7 mg L-1. ClO2 preoxidation/ClO2 disinfection is applicable for the control of effluent quality, but the ClO2- concentration still has an excessive risk when using 0.8 mg L-1 and 0.6 mg L-1 ClO2 for the two process, respectively. In the ClO2/NaClO combination process, the ClO2- concentration is below 0.6 mg L-1, and trihalomethane (THM) and haloacetic acid (HAA) concentrations are lower than 60% of the maximum contaminant levels (MCLs) set by the World Health Organization (WHO). Further, the formation of ClO2- is more effectively controlled by NaClO preoxidation/ClO2 disinfection than ClO2 preoxidation/NaClO disinfection.

19.
Environ Geochem Health ; 41(3): 1459-1472, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30542780

RESUMO

With the change in global climate and environment, water scarcity has been of great concern around the word and exacerbated by serious pollution in water resources. Pollutants accumulated in sediments are threatening water safety and ecological security. Different from others focusing on prevalent heavy metals (Cu, Pb, Zn, As, Cd, Cr, Hg, etc.), in this study, some unheeded metal pollutants Tl, Sb, Mo, Sr, Co, V, Ti, Ca, Mg, Be and Li were monitored in sediments of the Xiangjiang River, China. It was found that there was no remarkable vertical variation with depth, but the seasonal characteristics of Tl, Sb, Mo, Be and Li. The enrichment, pollution and potential ecological risk of Tl, Sb and Mo were revealed by the enrichment factor (EF), geoaccumulation index (Igeo), pollution load index (PLIsite and PLIzone) and potential ecological risk index (RI). It is noticed that the pollution of Tl mainly occurred in summer at midstream and downstream and Mo pollution was much higher than Sb in summer and the reverse in other seasons. Additionally, sediment quality on east side was worse than on west side in Songbai section of the Xiangjiang River. For the first time, the toxic-response factor was figured out as Mo = 18, Tl = 17, Sb = 13, Sr = 6, Co = Be = 1, V = Li = 0, and importantly, the high potential ecological risk of Tl, Sb and Mo needs to be taken seriously for the comprehensive assessment on watershed environmental quality.

20.
Medicine (Baltimore) ; 97(48): e13422, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30508951

RESUMO

RATIONALE: Most of esophageal rupture is a very serious life-threatening benign gastrointestinal tract disease with high mortality. However, there are a few cases of spontaneous esophageal rupture during gastroscopy. PATIENT CONCERNS: A 57-year-old man who underwent a routine diagnostic gastroscopy due to food obstruction was reported. During the gastroscopy, he vomited severely, which was followed by severe left chest pain radiating into the back and upper abdomen. The diagnosis was made by computed tomography (CT) scan without delay. Enhanced CT showed extensive mediastinal emphysema, a small amount of left pleural effusion, and a 6 cm tear was confirmed in the lower esophagus posteriorly. DIAGNOSES: The patient was diagnosed with an intrathoracic rupture type of spontaneous esophageal rupture. INTERVENTIONS: The patient received endoscopic suturing techniques under endotracheal intubation, titanium clip clamping, and over the scope clip (OTSC) sealing. OUTCOMES: The procedure was smooth and the patient recovered well after operation. LESSONS: During gastroscopy, the risk of esophageal rupture should be considered due to sudden pain caused by severe nausea and vomiting. Esophageal rupture can rapidly lead to severe life-threatening infections such as empyema and mediastinitis. Therefore, awareness of this condition is important so that appropriate treatment can rapidly be implemented to increase the likelihood of a good outcome.

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