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1.
Future Oncol ; 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36651355

RESUMO

Background: To investigate the expression status of estrogen receptor (ER), progesterone receptor (PR) and HER2 in patients with breast cancer brain metastases (BM). Methods: Patients who underwent craniotomy for BM were included. The status of ER, PR and HER2 (including HER2-low expression) in primary breast tumors (PT), BM and extra-BM (EM) was determined. Results: Between PT and BM, conversion of hormone receptor and HER2 occurred in 28% (30/107) and 12% (10/86) of cases. When considering three-tiered categorization of HER2, the conversion rate reached 31%. In the paired EM and BM (n = 39), the discordance rates were 18%, 3% and 22%, respectively. Conclusion: Receptor discordance was dynamic and relevant, especially using new HER2 categorization.

2.
Environ Res ; 227: 115695, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-36958381

RESUMO

OBJECTIVE: Epidemiological studies have linked ambient pollutants with tuberculosis (TB) risk, but the association has not been fully understood. Here, for the first time, we applied whole-genome sequencing (WGS) to assess the reproductive state of Mycobacterium tuberculosis (MTB) by profiling the mutation rate of MTB (MTBMR) during within-host endogenous reactivated progression, intending to dissect the actual effects of ambient pollutants on the endogenous reactivation. METHODS: We conducted a retrospective cohort study on bacteriologically confirmed TB patients and followed them for relapse in Jiangsu and Sichuan Province, China. Endogenous and exogenous activation were distinguished by WGS of the pathogen. The average concentration of air pollution was estimated by considering a lag of 0-1 to 0-12 months. We applied a generalized additive model with a Poisson function to evaluate the relationships between ambient pollutants exposure and MTBMR. RESULTS: In the single-pollutant adjusted models, the maximum effect for PM10 (MTBMR increase: 81.87%, 95% CI: 38.38, 139.03) and PM2.5 (MTBMR increase: 73.91%, 95% CI: 22.17, 147.55) was observed at a lag of 0-12 months for every 10 µg/m³ increase. For SO2, the maximum effect was observed at lag 0-8 months, with MTBMR increasing by 128.06% (95% CI: 45.92, 256.44); and for NO2, the maximum effect was observed at lag 0-9 months, with MTBMR increasing by 124.02% (95% CI: 34.5, 273.14). In contrast, the O3 concentration was inversely associated with MTBMR, and the maximum reduction of MTBMR was 6.18% (95% CI: -9.24, -3.02) at a lag of 0-9 months. Similar results were observed for multi-pollutant models. CONCLUSIONS: Increased exposure to ambient pollutants (PM10, PM2.5, SO2, and NO2) contributed to a faster MTBMR, indicating that MTB exhibits increased reproductive activity, thus accelerating within-host endogenous reactivation. O3 exposure could decrease the MTBMR, suggesting that MTB exerts low reproductive activity by inhibiting within-host endogenous activation.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Mycobacterium tuberculosis , Tuberculose , Humanos , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Poluentes Ambientais/toxicidade , Material Particulado/toxicidade , Material Particulado/análise , Dióxido de Nitrogênio/análise , Estudos Retrospectivos , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Exposição Ambiental/análise , Tuberculose/epidemiologia , China/epidemiologia
3.
Chemistry ; 28(64): e202202019, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-35971905

RESUMO

Cocatalyst plays an important role in efficient charge transfer and separation for photocatalysis. Herein, a MoS2 /CdS photocatalyst with MoS2 as cocatalyst was designed by using Mo-MOF and Cd-MOF as precursors. Due to the existence of rich sulfur vacancies and 1T phase, MoS2 shows strong charge capture and transport ability. The photo-generated electrons on conduction band (CB) can be bound by the sulfur vacancy of CdS and effectively transported to MoS2 through the compact interface between the CdS nanoparticles and 2D large-scale MoS2 . The optimal photocatalyst 1 %MoS2 /CdS exhibited dramatically improved photocatalytic hydrogen production activity, which is 28 times that of pristine CdS and even about 2 times that of 1 %Pt/CdS with same loading amount of noble metal Pt. This work highlights the role of Mo-MOF derived MoS2 with 1T-2H phases as a sustainable and prospective candidate of cocatalyst for improving charge separation and photocatalytic stability of MoS2 /CdS composites.

4.
Nanotechnology ; 33(34)2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35576909

RESUMO

To improve the shortcomings of narrow therapeutic range and low bioavailability of traditional preparations, a composite drug carrier that combines the advantages of biological carriers and synthetic carriers was prepared in this project. The biomimetic nano-delivery system outer membrane vesicles-polydopamine-mesoporous silica nanoparticle (OMVs-PDA-MSN-DOX) for oral administration is composed of OMVs ofEscherichia colias shell and doxorubicin-loaded MSN modified by PDA as core. Several characterization techniques thoroughly examined the nano-drug delivery system to confirm its surface morphology and chemical property. OMVs-PDA-MSN-DOX with a particle size of 150 nm showed significant cell selectivity and safety. We demonstrated that OMVs are capable of protecting pH-sensitive nanostructure from the oral route of administration in the short term. Importantly, OMVs-PDA-MSN-DOX could facilitate intestinal adhesion and improve DOX bioavailability. Overall, the OMVs-cloaked nanocarrier provides an efficient delivery platform for the oral targeting treatment of cancer with pH-sensitive nano-formulations.


Assuntos
Nanopartículas , Neoplasias , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Concentração de Íons de Hidrogênio , Indóis , Nanopartículas/química , Neoplasias/tratamento farmacológico , Polímeros , Porosidade , Dióxido de Silício/química
5.
J Microencapsul ; 37(7): 481-491, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32700606

RESUMO

AIM: In this study, 5-fluorouracil (5-FU) is delivered to target colon without the interference of mononuclear phagocyte system (MPS). METHODS: Outer membrane vesicles (OMVs) were used as the biological shield to disguise mesoporous silica (MSN) and 5-FU. OMVs-MSN-5-FU were prepared by high pressure co-extrusion, and characterised on the basis of size, drug loading, transmission electron microscope, infra-red spectroscopy, differential scanning calorimetry, thermal gravity analysis, % in vitro release, MTT assay, cell uptake and in vivo imaging. RESULTS: OMVs-MSN-5-FU with -18.22 ± 0.17 mV zeta potential and 90.4 ± 9.1 nm size were used for oral treatment of colon cancer. Drug loading of the drug was 50.22%±0.17 (w/w). The cumulative release of OMVs-MSN-5-FU reached 75.07%±0.94 in tumour microenvironment. The percentage of cell viability of OMVs-MSN-5-FU was 33.75%±2.73. In vivo experiments results confirmed that OMVs-MSN-5-FU could be taken up by colon cancer cells. CONCLUSIONS: The study provided a promising nano platform for the targeting treatment of colon cancer.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Membrana Externa Bacteriana/química , Neoplasias do Colo/tratamento farmacológico , Portadores de Fármacos/química , Escherichia coli/química , Fluoruracila/administração & dosagem , Animais , Antimetabólitos Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Fluoruracila/uso terapêutico , Humanos , Camundongos Endogâmicos BALB C , Dióxido de Silício/química
6.
Fish Shellfish Immunol ; 77: 438-444, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29625245

RESUMO

As a new-found aquaculture pathogen, Spiroplasma eriocheiris, has resulted in inconceivable economic losses in aquaculture. In the infection of S. eriocheiris, the Procambarus clakii hemocytes have indicated to be major target cells. What was designed to examine in our study is the hemocytes' immune response at the protein levels. Before the pathogen was injected and after 192 h of post-injection, the differential proteomes of the crayfish hemocytes were analyzed immediately by isobaric tags for relative and absolute quantization (iTRAQ) labeling, followed by liquid chromatogramphytandem mass spectrometry (LC-MS/MS). This research had identified a total of 285 differentially expressed proteins. Eighty-three and 202 proteins were up-regulated and down-regulated, respectively, caused by the S. eriocheiris infection. Up-regulated proteins included alpha-2-macroglobulin (α2M), vitellogenin, ferritin, etc. Down-regulated proteins, involved with serine protease, peroxiredoxin 6, 14-3-3-like protein, C-type lectin, cdc42 homolog precursor, etc. The prophenoloxidase-activating system, antimicrobial action involved in the immune responses of P. clarkii is considered to be damaged due to S. eriocheiris infection. The present work could lay the foundation for future research on the proteins related to the susceptibility/resistance of P. clarkii to S. eriocheiris. In addition, it is helpful for our understanding molecular mechanism of disease processes in crayfishes.


Assuntos
Astacoidea/genética , Hemócitos/imunologia , Imunidade Inata/genética , Proteoma/imunologia , Spiroplasma/fisiologia , Animais , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/metabolismo , Astacoidea/imunologia , Astacoidea/microbiologia , Proteômica
7.
J Clin Microbiol ; 53(1): 131-5, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25355771

RESUMO

The increasing burden of drug-resistant tuberculosis (TB) poses an escalating threat to national TB control programs. To assist appropriate treatment for TB patients, accurate and rapid detection of drug resistance is critical. The GeneChip test is a novel molecular tool for the diagnosis of TB drug resistance. Performance-related data on GeneChip are limited, and evaluation in new and previously treated TB cases has never been performed. We evaluated the diagnostic performance of GeneChip in detecting resistance to rifampin (RMP) and isoniazid (INH) and in detecting multidrug-resistant tuberculosis (MDR-TB) in comparison with standard drug susceptibility testing (DST) and compared the results in a group of previously treated and newly detected TB patients in an urban area in southeastern China. One thousand one hundred seventy-three (83.8%) new cases and 227 (16.2%) previously treated cases were collected between January 2011 and September 2013. The GeneChip showed a specificity of 97.8% and a sensitivity of 94.8% for detection of RMP resistance and 97.3% and 70.9%, respectively, for INH resistance in new cases. For previously treated cases, the overall sensitivity, specificity, and agreement rate are 94.6%, 91.3%, and 92.1%, respectively, for detection of RMP resistance and 69.7%, 95.4%, and 86.8%, respectively, for INH resistance. The sensitivity and specificity of MDR-TB were 81.8% and 99.0% in new cases and 77.8% and 93.4% in previously treated cases, respectively. The GeneChip system provides a simple, rapid, reliable, and accurate clinical assay for the detection of TB drug resistance, and it is a potentially important diagnostic tool in a high-prevalence area.


Assuntos
Mycobacterium tuberculosis/genética , Análise de Sequência com Séries de Oligonucleotídeos/normas , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antituberculosos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Adulto Jovem
8.
Sci Total Environ ; 924: 171416, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38447715

RESUMO

Textile sludge is a by-product produced during the wastewater treatment process in the textile printing and dyeing industry. Textile sludge is rich in heavy metal elements, which makes it a potential risk to the surrounding environment. This study designs a magnesium oxychloride cement (MOC) components to solidify harmful substances in textile sludge and studies the influence of textile sludge ash (TSA) on the mechanical properties and microstructure of MOC samples. The results indicated that adding 5 %-20 % TSA is beneficial for increasing the compressive strength of air-cured MOC paste and improving its water resistance. Meanwhile, the MOC sample shows volume expansion in 168 h, which is related to the further hydration of residual MgO. Incorporating 10 %-20 % TSA substantially increased the volume expansion ratio of the mixture compared to plain MOC sample. In addition, the porosity of TSA-modified MOC after water curing did not change significantly compared to the sample before water curing, while the pore structure of plain MOC after water curing significantly coarsened. This is mainly because TSA reacts with MOC and generates Mg-Al-Cl-Si-H and Mg-Cl-Si-H gels, consequently improving the water stability of MOC sample. At the nanoscale, the 3/5-phase crystal and unreacted MgO content in the 15 % TSA-modified MOC sample is relatively reduced by 7.79 % and 25 %, respectively, compared to the plain sample, but the 13 % gel phase is detected. In addition, the MOC component can effectively solidify heavy metal elements in textile sludge. For the leachate of 20 % TSA-modified MOC paste, the Ni element is not detected, and its solidifying effect on heavy elements such as Zn and Mn exceeded 99 %.

9.
Sci Total Environ ; 926: 171513, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38460695

RESUMO

Drinking water treatment sludge (DWTS) is a by-product of water treatment, and it is difficult to recycle to high value and poses potential environmental risks. Recycling DWTS into cement-based materials is an effective measure to achieve its high-volume utilization and reduce its environmental load. DWTS is rich in silica-alumina phases and has potential pozzolanic activity after drying, grinding and calcination, giving it similar properties to traditional supplementary cementitious materials. Adjusting the sludge production process and coagulant type will change its physical and chemical properties. Adding a small amount of DWTS can generate additional hydration products and refine the pore structure of the cement sample, thus improving the mechanical properties and durability of the sample. However, adding high-volume DWTS to concrete causes microstructural deterioration, but it is feasible to use high-volume DWTS to produce artificial aggregates, lightweight concrete, and sintered bricks. Meanwhile, calcined DWTS has similar compositions to clay, which makes it a potential raw material for cement clinker production. Cement-based materials can effectively solidify heavy metal ions in DWTS, and alkali-activated binders, magnesium-based cement, and carbon curing technology can further reduce the risk of heavy metal leaching. This review provides support for the high-value utilization of DWTS in cement-based materials and the reduction of its potential environmental risks.

10.
BMC Public Health ; 13: 1171, 2013 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-24330553

RESUMO

BACKGROUND: Drug-resistant tuberculosis (TB) has emerged as a major challenge toward TB control and prevention. In Lianyungang city, the extent and trend of drug resistant TB is not well known. The objective of the survey was to assess drug resistance pattern of MTB and risk factors for drug resistant TB, including multidrug resistance tuberculosis (MDR-TB) in this area. METHODS: We performed drug susceptibility testing on Mycobacterium tuberculosis (MTB) isolates with first- and second-line anti-tuberculosis drugs of 1012 culture positive TB cases by using the proportion method, who were consecutively enrolled from January 2011 to December 2012 in Lianyungang city, China. The patterns of drug resistance in MTB were investigated and multiple logistic regression analysis was performed to assess the risk factors for drug resistant TB. RESULTS: Among the 1012 strains tested, 308 (30.4%) strains were resistant to at least one first-line drug; the prevalence of MDR-TB was 88 (8.7%), 5 (0.5%) strains were found to be extensively drug-resistant tuberculosis (XDR-TB). Female gender was a risk factor for MDR-TB (adjusted odds ratio (aOR) 1.763, 95% CI (1.060-2.934). The aged 28-54 years was significantly associated with the risk of MDR-TB with an aOR: 2.224, 95% CI (1.158-4.273) when compared with those 65 years or older. Patients with previous treatment history had a more than 7-fold increased risk of MDR-TB, compared with those never previously treated. CONCLUSIONS: The burden of drug resistant TB cases is sizeable, which highlights an urgent need to reinforce control, detection and treatment strategies for drug resistant TB.


Assuntos
Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Adulto , Fatores Etários , Idoso , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , China/epidemiologia , Farmacorresistência Bacteriana Múltipla , Tuberculose Extensivamente Resistente a Medicamentos/tratamento farmacológico , Tuberculose Extensivamente Resistente a Medicamentos/epidemiologia , Tuberculose Extensivamente Resistente a Medicamentos/etiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Recidiva , Fatores de Risco , Fatores Sexuais , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/etiologia
11.
Front Genet ; 14: 1139087, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36926586

RESUMO

Background: Drought stress can limit the growth and development of tomato seedlings and cause considerable loss of tomato yield. Exogenous abscisic acid (ABA) and calcium (Ca2+) can effectively alleviate the damage of drought stress to plants in part because Ca2+ acts as a second messenger in the drought resistance pathway. Although cyclic nucleotide-gated ion channels (CNGCs) are common non-specific Ca2+ osmotic channels in cell membranes, a thorough understanding of the transcriptome characteristics of tomato treated with exogenous ABA and Ca2+ under drought stress is necessary to characterize the molecular mechanism of CNGC involved in tomato drought resistance. Results: There were 12,896 differentially expressed genes in tomato under drought stress, as well as 11,406 and 12,502 differentially expressed genes after exogenous ABA and Ca2+ application, respectively. According to functional annotations and reports, the 19 SlCNGC genes related to Ca2+ transport were initially screened, with 11 SlCNGC genes that were upregulated under drought stress and downregulated after exogenous ABA application. After exogenous Ca2+ application, the data showed that two of these genes were upregulated, while nine genes were downregulated. Based on these expression patterns, we predicted the role of SlCNGC genes in the drought resistance pathway and their regulation by exogenous ABA and Ca2+ in tomato. Conclusion: The results of this study provide foundational data for further study of the function of SlCNGC genes and a more comprehensive understanding of drought resistance mechanisms in tomato.

12.
Environ Pollut ; 317: 120839, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36493937

RESUMO

Stabilizing/solidificating municipal solid waste incineration fly ash (MIFA) with cement is a common strategy, and it is critical to study the high-value utilization of MIFA in ordinary Portland cement (OPC) components. With this aim, binary-binding-system mortar was produced by partially replacing OPC (∼50%) with MIFA, and the effects of different curing regimes (steam curing and carbonation curing) on the properties of the cement mortar were studied. The results showed that the setting time of the cement paste was shorten with the increase of MIFA content, and steam curing accelerated the hardening of the mixture. Although the incorporation of MIFA reduced the strength of the mortar, compared to conventional curing method, steam curing and carbonation curing increased the 3-d strength of the mortar. For high-volume MIFA mortars, the CO2-cured samples had the highest long-term strength and lowest permeability. The incorporation of MIFA increased the initial porosity of the mortar, thereby significantly increasing the carbonation degree and crystallinity of the reaction product - CaCO3. Steam curing also further narrowed the difference in the hydration degree between MIFA-modified sample and plain paste, which may be due to the enhanced hydraulic reactivity of MIFA at high temperatures. Although the incorporation of MIFA increased the porosity of the mortar, this waste-derived SCM refined the bulk pore structure and decreased the interconnected porosity. Additionally, the heavy metal leaching contents of MIFA-modified mortars were all below 1%, which meet the requirements of Chinese standards. Compared with standard curing, steam curing and carbonation curing made the early-age and long-term performance of MIFA-modified mortar better, which can promote the efficient application of MIFA in OPC products.


Assuntos
Cinza de Carvão , Metais Pesados , Cinza de Carvão/análise , Incineração/métodos , Resíduos Sólidos/análise , Vapor , Metais Pesados/análise
13.
Sci Total Environ ; 876: 162804, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-36914134

RESUMO

Recycling waste materials (WMs) is a cost-effective method for saving natural resources, protecting the environment, and reducing the use of high-carbon raw materials. This review aims to illustrate the impact of solid waste on the durability and microstructure of ultra-high performance concrete (UHPC) and to provide guidance for the research of eco-friendly UHPC. The results show that the proper use of solid waste to replace part of the binder or aggregate has a positive effect on the performance development of UHPC, but further enhancement techniques should be developed. When solid waste is prepared as a binder, the durability of waste based UHPC can be effectively improved by grinding and activation. When solid waste is used as an aggregate, its rough surface, potential reactivity and internal curing effect are also beneficial to the improvement of UHPC performance. Since UHPC has a dense microstructure, it can effectively prevent the leaching of harmful elements (heavy metal ions) in solid waste. However, the effect of waste modification on the reaction products of UHPC needs to be further studied, and design methods and testing standards suitable for eco-friendly UHPCs should be developed. The use of solid waste in UHPC effectively reduces the carbon footprint of the mixture, which is beneficial to the development of cleaner production technologies.

14.
Sci Total Environ ; 873: 162456, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36842600

RESUMO

For eutrophic water bodies, potassium permanganate is an effective pre-oxidant to remove algae and its residue in water treatment sludge. Recycling water treatment sludge in concrete is an environmentally friendly and high-value utilization measure. However, little research has been done on the effect of manganese-rich drinking water sludge ash (DWSA) on concrete. The effect of water-binder ratio (w/b) on strength, shrinkage and microstructural characteristics of concrete containing DWSA was investigated, and the structural behavior was explained from a nanoscale perspective. The results show that recycling 10 % DWSA in concrete improved the strength and shrinkage resistance of the samples. Reducing the w/b effectively increased the strength of DWSA-modified concrete and reduced the shrinkage deformation. The paste with high w/b had higher contents of non-evaporated water and calcium hydroxide, as well as higher reaction degree of DWSA. Nanoscale characterization shows that reducing the w/b reduced the volume fraction of pore and unhydrated phases in the matrix and increased the proportion of high-density C-S-H. Meanwhile, reducing the w/b also reduced the interfacial transition zone width of DWSA-modified concrete. Recycling DWSA in concrete effectively reduced the total carbon footprint and cost of the mixture. The combined application of reducing the w/b and incorporating DWSA effectively improved the economic and environmental benefits of concrete material. For the concrete modified with 10 % DWSA (w/b = 0.3), its cost and carbon emissions are reduced by 14 %-21 % and 19 %-25 % compared with the reference sample, respectively. Overall, this study reveals the action mechanism of DWSA in cement system at different w/b from nanoscale perspective, and gives a new insight on determining the optimal w/b in full-scale application of DWSA concrete.

15.
Sci Total Environ ; 836: 155424, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-35504383

RESUMO

On islands far away from the mainland, the raw materials for concrete production are often more difficult to obtain. Converting the coral waste generated during the island construction process into a marine ultra-high performance concrete (UHPC) mixture is an eco-friendly strategy. Coral powder (CP) is used to partially replace cement and silica fume (SF), and its mechanical strength, microstructure and environmental benefits are evaluated. Results show that using a small amount of CP (5%) to replace cement can improve the mechanical properties of UHPC, but the strength of UHPC decreases with the further increase of CP content. From the perspective of nanoindentation test, an appropriate amount of CP refines the pore structure of the UHPC matrix and increases the content of C-S-H, especially the proportion of high-density C-S-H. When 15% of SF is replaced by CP (SF15), the strength of UHPC decreases due to the decrease of C-S-H phase and the deterioration of microstructure. In terms of the width of the interface transition zone, the width of the C5 sample (CP replace 5% cement) is decreased by 16.7% compared with the control group, while the width of the SF15 group is increased by 38.9%. Compared with conventional UHPC, CP-based UHPC has lower carbon emission and non-renewable energy consumption, which effectively utilizes waste and promotes sustainability.


Assuntos
Antozoários , Materiais de Construção , Animais , Pós , Reciclagem , Dióxido de Silício
16.
Dalton Trans ; 51(15): 5841-5858, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35343533

RESUMO

In heterojunction photocatalytic materials, the size of the nanoparticles and electron-hole separation efficiency have a great influence on the photocatalytic hydrogen production activity. In this work, for the first time, a strategy of combining sulfur vacancy engineering and quantum size control for constructing CdS (MOF)/PI heterojunctions was reported. Sulfur-deficient CdS (MOF) nanoparticles with a size of 5-10 nm were derived from in situ sulfurization of Cd-MOF precursors and highly dispersed on the surface of 2D polyimide (PI). The experimental and characterization results demonstrated that CdS (MOF)/PI heterojunctions possess broader and stronger light absorption towards the visible region than pristine PI. More importantly, a considerable amount of sulfur vacancies were introduced into CdS (MOF) nanoparticles. The presence of abundant surface and bulk sulfur vacancies created more unsaturated coordinated Cd 3c atoms, which increased the proportion of the (002) crystal planes that act as highly active crystal planes of CdS (MOF), providing more active reaction sites. The surface sulfur vacancy level located near the Fermi level serves as the photogenerated electron trap level, thereby increasing the efficiency of electron-hole separation and further prolonging the lifetime of photogenerated electrons. As a result, the 18%CdS(MOF)/PI heterojunction exhibited a higher hydrogen evolution rate of 8640 µmol g-o after 4 hours of illumination, which was 20 times higher than that of 18%CdS/PI under visible light irradiation. This work highlights the role of sulfur defects in the modification of the CdS (MOF)/PI heterojunction as a feasible strategy for improving charge separation and photocatalytic performance.

17.
Sci Total Environ ; 829: 154546, 2022 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-35302022

RESUMO

The development of magnesium oxychloride cement can effectively utilize the waste of potash industry and reduce its harm to the environment. Although magnesium oxychloride cement paste (MOCP) has excellent performance in dry environment, its performance is greatly deteriorated in water or humid environment, which severely limits its practical application. In order to improve the water resistance of MOCP, MOCP was modified by various gypsum in this study, and the intrinsic mechanism was explored. Results showed that replacing MgO with gypsum delayed the setting time of MOCP and effectively improved its volume stability. Although the incorporation of gypsum reduced the 14-d air-cured compressive strength of MOCP, waste gypsum was able to significantly improve the water resistance of MOCP compared to natural gypsum. When 80% flue gas desulfurization gypsum and phosphogypsum (weight of magnesium oxide) were incorporated into MOCP, the 14-d air-cured compressive strength of MOCP was only decreased by 14.49% and 15.94% compared with the control group, but its 28-d water immersion strength retention coefficient (SRC) could still reach 61.02% and 46.55%, respectively. However, for the control group and MOCP with 80% natural gypsum, the 28-d SRC were only 28.99% and 8.41%. The incorporation of high-volume waste gypsum to MOCP not only reduced the relative content of MgO, but also improved the stability of the 5-phase in water, which was beneficial to improve the water resistance of MOCP. In addition, high-volume waste gypsum-modified MOCP had lower cost and carbon emissions, and exhibited superior water resistance and sustainability compared to existing MOCP compositions.


Assuntos
Sulfato de Cálcio , Magnésio , Força Compressiva , Materiais Dentários , Óxido de Magnésio , Água
18.
J Glob Antimicrob Resist ; 30: 335-339, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35817264

RESUMO

OBJECTIVES: Isoniazid resistance might be overlooked because of the priority of detection of rifampicin-resistant tuberculosis. It was urgent to reveal the current situation of isoniazid-resistant tuberculosis (HR-TB), including unfavorable outcomes and bacterial factors. METHODS: A retrospective cohort study was undertaken including 120 patients with HR-TB and 193 patients with drug-sensitive tuberculosis (DS-TB). 24-loci MIRU-VNTR and Spoligotyping were adopted for genotyping. RESULTS: We found 106 cases (88.3%) of HR-TB and 165 cases (85.5%) of DS-TB were treated with the first-line drugs. Meanwhile, 12 (10.0%) patients of the HR-TB group and 7 (3.63%) patients of the DS-TB group involved adverse treatment outcomes (χ2 = 5.271, P = 0.028). Seventy-eight DNA from HR Mycobacterium tuberculosis and 114 DNA from DS M. tuberculosis were available for MIRU-VNTR and Spoligotyping. The clustering rate was 17.9% (14/78) for HR-TB and 16.7% (19/114) for DS-TB, and reached no significant difference (χ2 = 0.05, P = 0.8171). The Beijing family strains accounted for 83.7% (65/78) of HR-TB and 80.0% (91/114) of DS-TB (χ2 = 0.37, P = 0.5407). The adverse treatment outcomes for HR-TB all occurred in patients infected with Beijing family strains (13.8%), but no difference was found between Beijing and non-Beijing genotypes (P = 0.342). CONCLUSION: Adverse outcomes were significantly more frequent in patients with HR-TB than in those with DS-TB, and most of the patients with HR-TB were receiving a standard first-line regimen. Although the clustering rate and Beijing genotype distribution amongst HR-TB and DS-TB showed no significant difference, the Beijing genotype was the dominant genotype and its proportion was slightly higher amongst HR-TB than amongst DS-TB.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , China , Genótipo , Humanos , Isoniazida/farmacologia , Isoniazida/uso terapêutico , Mycobacterium tuberculosis/genética , Estudos Retrospectivos , Resultado do Tratamento , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
19.
Sci Total Environ ; 849: 157871, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-35952880

RESUMO

Magnesium oxychloride cement (MOC) has received extensive attention as an eco-friendly cement, but its poor water resistance limits its engineering applications. In this study, MOC mixture (MOCM) was modified with 10-50 % rice husk ash (RHA) (wt% of MgO), and the development of their fresh properties, mechanical strength and microstructure was investigated. The results show that the incorporation of RHA to MOCM increases the setting time of the mixture and reduces its flowability. Due to the fine particle size and high reactivity of RHA, the incorporation of an appropriate amount of RHA to MOCM improves the matrix compactness, thereby enhancing the compressive strength of the samples. Although the microstructure of MOCM deteriorates and the strength decreases after immersion in water, the strength retention coefficient of MOCM with 50 % RHA increases by 24.57 % compared with that of plain MOCM. The incorporation of RHA not only reduces the relative content of magnesium oxide in MOCM, but also generates Mg-Cl-Si-H gel, which is beneficial to improve the water resistance of MOCM. Meanwhile, with the increase of RHA content, the carbon emission of MOCM also decreases. Compared with other modification methods, RHA-modified MOCM performs better in terms of water resistance, environmental benefits and strength enhancement.


Assuntos
Oryza , Carbono , Magnésio , Óxido de Magnésio , Oryza/química , Água/química
20.
Sci Rep ; 11(1): 17951, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34504243

RESUMO

Most Mycobacterium tuberculosis (Mtb) resistant to rifampicin (RIF) has mutations in the rpoB gene, while most Mtb resistant to isoniazid (INH) has mutations in the katG gene or inhA promoter. We used gene chip technology to detect mutations in these genes to determine the resistance of Mtb to RIF and INH. A total of 4148 clinical specimens with sputum smear positivity for acid-fast bacilli (AFB) were detected. Then, taking the results of the drug sensitivity test (DST) as the reference standard, the detection efficiency of sputum samples from different grades of positive smears was compared in detail. We found that the sensitivity of the gene chip method for detecting sputum samples with a grade ≥ AFB 2 + was higher than that of sputum samples with a grade ≤ AFB 1 + (P < 0.05). When the grade of the sample was ≤ AFB 1 +, the sensitivity of the gene chip method was 72.6% for RIF, 67.3% for INH, and 60.0% for MDR-TB. When the grade of the sample was ≥ AFB 2 +, the sensitivity of the gene chip method was 84.5% for RIF, 78.2% for INH, and 73.9% for MDR-TB. The results show that gene chip technology can be directly used to diagnose drug-resistant tuberculosis in clinical specimens, and the diagnostic efficiency for the detection of sputum specimens with a grade ≥ AFB 2 + is better than that of other sputum specimens.


Assuntos
Antibióticos Antituberculose/uso terapêutico , Farmacorresistência Bacteriana Múltipla/genética , Isoniazida/uso terapêutico , Mutação , Mycobacterium tuberculosis/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Rifampina/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Proteínas de Bactérias/genética , Catalase/genética , Códon/genética , RNA Polimerases Dirigidas por DNA/genética , Humanos , Testes de Sensibilidade Microbiana , Oxirredutases/genética , Estudos Retrospectivos , Sensibilidade e Especificidade , Escarro/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
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