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1.
Talanta ; 261: 124664, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37209586

RESUMO

Bacillus anthracis spores can make humans infected with vicious anthrax, so it is significant to detect their biomarker 2,6-pyridinedicarboxylic acid (DPA). The development of dual-modal methods for DPA detection that are more flexible in practical applications remains a challenge. Herein, colorimetric xylenol orange (XO) was modified on fluorescent CdTe quantum dots (QDs) for dual-modal detection of DPA through competitive coordination. After the binding of XO on CdTe QDs via coordination with Cd2+, CdTe QDs displayed quenched red fluorescence and the bound XO was presented as red color. The competitive coordination of DPA with Cd2+ made XO released from CdTe QDs, causing the enhanced red fluorescence of CdTe QDs and the yellow color of free XO. On this basis, DPA was rapidly (1 min) quantified through fluorescent and colorimetric modes within the ranges of 0.1-5 µM and 0.5-40 µM, respectively. The detection limits for DPA were calculated as low as 42 nM and 240 nM, respectively assigned to fluorescent and colorimetric modes. The level of urinary DPA was further measured. Satisfactory relative standard deviations (fluorescent mode: 0.1%-10.2%, colorimetric mode: 0.8%-1.8%) and spiked recoveries (fluorescent mode: 100.0%-115.0%, colorimetric mode: 86.0%-96.6%) were obtained.


Assuntos
Antraz , Compostos de Cádmio , Pontos Quânticos , Humanos , Antraz/diagnóstico , Corantes Fluorescentes , Cádmio , Colorimetria , Telúrio , Espectrometria de Fluorescência/métodos , Biomarcadores
2.
J Environ Manage ; 339: 117899, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37054592

RESUMO

Foundry dust is the main refractory solid waste in the foundry industry, and its resource utilization is a top priority for realizing green and cleaner production. The massive amount of coal dust in foundry dust is a potential impediment to the recycling of foundry dust, and the efficient separation of coal dust is crucial to solving the above problems. In this paper, the flotation separation of coal dust from foundry dust enhanced by pre-soaking assisted mechanical stirring was reported. The influence of pre-soaking, stirring speed, and stirring time on the flotation results of foundry dust was systematically studied, and the enhancement mechanism was analyzed based on the microstructure and hydrophobicity of foundry dust. Flotation kinetics experiments with different stirring time were conducted to clarify the flotation process of foundry dust. The results indicate that the pre-soaking of foundry dust is beneficial for the water-absorbing swelling of clay minerals coated on the surface of coal dust, and the subsequent mechanical stirring pretreatment promotes the monomer dissociation of foundry dust, which increases the contact angle of foundry dust and considerably improves the flotation results. The optimal stirring speed and stirring time were 2400 rpm and 30 min, respectively. The classical first-order model presented the highest degree of fitting with the flotation data among the five flotation kinetics models. Therefore, the pre-soaking assisted mechanical stirring is a promising method for promoting flotation separation and the complete recycling of foundry dust.


Assuntos
Carvão Mineral , Poeira , Resíduos Sólidos/análise , Minerais , Reciclagem/métodos
3.
Vaccines (Basel) ; 11(3)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36992262

RESUMO

Candida parapsilosis poses huge treatment challenges in the clinical settings of South Africa, and often causes infections among immunocompromised patients and underweight neonates. Cell wall proteins have been known to play vital roles in fungal pathogenesis, as these are the first points of contact toward environments, the host, and the immune system. This study characterized the cell wall immunodominant proteins of pathogenic yeast C. parapsilosis and evaluated their protective effects in mice, which could add value in vaccine development against the rising C. parapsilosis infections. Among different clinical strains, the most pathogenic and multidrug-resistant C. parapsilosis isolate was selected based on their susceptibility towards antifungal drugs, proteinase, and phospholipase secretions. Cell wall antigens were prepared by ß-mercaptoethanol/ammonium bicarbonate extraction from selected C. parapsilosis strains. Antigenic proteins were identified using LC-MS/MS, where 933 proteins were found, with 34 being immunodominant. The protective effect of the cell wall immunodominant proteins was observed by immunizing BALB/c mice with cell wall protein extracts. After the immunization and booster, the BALC/c mice were challenged with a lethal dose of C. parapsilosis. In vivo results demonstrated increased survival rates and lower fungal burden in vital organs in the immunized mice compared to the unimmunized mice, thereby confirming the immunogenic property of cell wall-associated proteins of C. parapsilosis. Therefore, these results advocated the potential of these cell wall proteins to act as biomarkers for the development of diagnostic assays and/or vaccines against infections caused by C. parapsilosis.

4.
J Infect Public Health ; 16(2): 233-249, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36603376

RESUMO

Over the last few years, the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) unleashed a global public health catastrophe that had a substantial influence on human physical and mental health, the global economy, and socio-political dynamics. SARS-CoV-2 is a respiratory pathogen and the cause of ongoing COVID-19 pandemic, which testified how unprepared humans are for pandemics. Scientists and policymakers continue to face challenges in developing ideal therapeutic agents and vaccines, while at the same time deciphering the pathology and immunology of SARS-CoV-2. Challenges in the early part of the pandemic included the rapid development of diagnostic assays, vaccines, and therapeutic agents. The ongoing transmission of COVID-19 is coupled with the emergence of viral variants that differ in their transmission efficiency, virulence, and vaccine susceptibility, thus complicating the spread of the pandemic. Our understanding of how the human immune system responds to these viruses as well as the patient groups (such as the elderly and immunocompromised individuals) who are often more susceptible to serious illness have both been aided by this epidemic. COVID-19 causes different symptoms to occur at different stages of infection, making it difficult to determine distinct treatment regimens employed for the various clinical phases of the disease. Unsurprisingly, determining the efficacy of currently available medications and developing novel therapeutic strategies have been a process of trial and error. The global scientific community collaborated to research and develop vaccines at a neck-breaking speed. This review summarises the overall picture of the COVID-19 pandemic, different mutations in SARS-CoV-2, immune response, and the treatment modalities against SARS-CoV-2.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , COVID-19/imunologia , COVID-19/terapia , Mutação , Pandemias/prevenção & controle , SARS-CoV-2/genética
5.
J Hazard Mater ; 402: 124124, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33077269

RESUMO

Clay sand casting generates a large amount of foundry dust (FD), and the presence of coal powder in the FD makes it difficult to recycle and utilize. The landfill of the FD creates a serious environmental pollution and wastes a valuable resource. To improve the above situation, the FD was analyzed and characterized by X-ray fluorescence spectrometer (XRF), X-ray diffraction (XRD) and electron probe microanalyzer (EPMA). An ultrasonic-assisted flotation process was developed for the comprehensive utilization of the FD, and the effects of ultrasonic time on the flotation performance and flotation kinetics were investigated. In addition, the two-stage flotation of the FD was conducted. Obtained results showed that the FD mainly consisted of coal powder and clay minerals, and the coal powder was covered by clay minerals. The separation efficiency of the coal powder and clay minerals can be significantly enhanced by ultrasonic pretreatment, and the optimal ultrasonic time was 30 min. The flotation kinetics analysis results indicated that the first-order model with rectangular distribution was more reasonable for the data fitting of the ultrasonic-assisted flotation. Furthermore, the concentrate and tailings obtained by the two-stage flotation had achieved an acceptable result, favoring the comprehensive utilization of the FD.

6.
Cureus ; 10(5): e2651, 2018 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-30034973

RESUMO

This study explores the effect of diuretics use on metabolic markers (i.e., the lipid profile) since thiazide diuretics are extensively used to treat cardiac patients with hypertension (HTN) and other comorbidities. The Embase and PubMed databases were searched for relevant English-language peer-reviewed articles. Different search terms and medical subject headings (MesH) terms were used to find the relevant articles. Our study included randomized controlled trials with hypertensive adult patients in the intervention group receiving thiazide diuretics; controls receiving any other diuretic or any other intervention for HTN where an intention to treat analysis was performed. We collected the demographic details, baseline lipid profile values, and end-of-study lipid profile values of all the participants in the studies along with the standard deviation of each value to calculate the net change effect. Five studies were included. We used the Q-test and I2 index for heterogeneity and the inverse variance method for weighting. We used the fixed effects model for total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) because TC and LDL-C had no heterogeneity (I2 was 0%). We used a random-effects model for triglycerides (TG) and high-density lipoprotein cholesterol (HDL-C), which showed moderate heterogeneity (I2 was 57.2% and 59.5%, respectively). We used the Cochrane quality assessment to assess the quality level of the included studies. We used a funnel plot to avoid publication bias. Diuretics have a significant effect on lipid profiles. However, because this conclusion is supported by a low number of studies, further research is needed, and physicians are advised to use their best clinical judgment until the relationship between diuretics and lipid profiles seen in this study can be further supported by additional studies.

7.
Front Chem ; 6: 648, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30687695

RESUMO

Nickel-rich ternary layered oxide (LiNi0.80Co0.15Al0.05O2, LNCA) cathodes are favored in many fields such as electric vehicles due to its high specific capacity, low cost, and stable structure. However, LNCA cathode material still has the disadvantages of low initial coulombic efficiency, rate capability and poor cycle performance, which greatly restricts its commercial application. To overcome this barrier, a polypyrrole (PPy) layer with high electrical conductivity is designed to coat on the surface of LNCA cathode material. PPy coating layer on the surface of LNCA successfully is realized by means of liquid-phase chemical oxidation polymerization method, and which has been verified by the scanning electron microscopy (SEM), transmission electron microscope (TEM) and fourier transform infrared spectroscopy (FTIR). PPy-coated LNCA (PL-2) exhibits satisfactory electrochemical performances including high reversible capacity and excellent rate capability. Furthermore, the capability is superior to pristine LNCA. So, it provides a new structure of conductive polymer modified cathode materials with good property through a mild modification method.

8.
Front Chem ; 6: 643, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30671428

RESUMO

The high energy density lithium ion batteries are being pursued because of their extensive application in electric vehicles with a large mileage and storage energy station with a long life. So, increasing the charge voltage becomes a strategy to improve the energy density. But it brings some harmful to the structural stability. In order to find the equilibrium between capacity and structure stability, the K and Cl co-doped LiNi0.5Co0.2Mn0.3O2 (NCM) cathode materials are designed based on defect theory, and prepared by solid state reaction. The structure is investigated by means of X-ray diffraction (XRD), rietveld refinements, scanning electron microscope (SEM), XPS, EDS mapping and transmission electron microscope (TEM). Electrochemical properties are measured through electrochemical impedance spectroscopy (EIS), cyclic voltammogram curves (CV), charge/discharge tests. The results of XRD, EDS mapping, and XPS show that K and Cl are successfully incorporated into the lattice of NCM cathode materials. Rietveld refinements along with TEM analysis manifest K and Cl co-doping can effectively reduce cation mixing and make the layered structure more complete. After 100 cycles at 1 C, the K and Cl co-doped NCM retains a more integrated layered structure compared to the pristine NCM. It indicates the co-doping can effectively strengthen the layer structure and suppress the phase transition to some degree during repeated charge and discharge process. Through CV curves, it can be found that K and Cl co-doping can weaken the electrode polarization and improve the electrochemical performance. Electrochemical tests show that the discharge capacity of Li0.99K0.01(Ni0.5Co0.3Mn0.2)O1.99Cl0.01 (KCl-NCM) are far higher than NCM at 5 C, and capacity retention reaches 78.1% after 100 cycles at 1 C. EIS measurement indicates that doping K and Cl contributes to the better lithium ion diffusion and the lower charge transfer resistance.

9.
Chin Med J (Engl) ; 116(7): 972-5, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12890364

RESUMO

OBJECTIVE: To investigate the chest X-ray manifestations of SARS cases. METHODS: A retrospective study was conducted among 52 clinically confirmed SARS patients from February 9 to May 10, 2003. Chest X-ray scanning was performed at a interval of 1 - 3 days according to the requirements. The manifestations and special features of SARS in X-ray were analyzed. RESULTS: Small or large patchy shadows with intensive density in both lungs were observed in 31 cases, ground-glass like opacification in 16, small patchy shadows in one lung lobe or one lung segment in 18, nodular shadows in one lung segment in 1, and increased lung marking in lung interstitial tissues in 2. Rapidly changing consolidations revealed in chest X-ray images were found to be associated with SARS infections, and they were not affected by treatment with antibiotics. CONCLUSION: Chest X-ray provides a sensitive and specific method for the diagnosis and treatment of SARS, and those present with symptoms and signs should undergo chest X-ray scanning every 1 - 3 days.


Assuntos
Radiografia Torácica , Síndrome Respiratória Aguda Grave/diagnóstico por imagem , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
10.
Zhonghua Er Ke Za Zhi ; 41(9): 645-7, 2003 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-14733797

RESUMO

OBJECTIVE: To explore clinical and chest X-ray features of SARS in children to facilitate correct diagnosis. METHODS: Clinical manifestations and chest X-ray findings in five children suffering from SARS admitted for treatment in the hospital between February and May, 2003 in Shenzhen area were analyzed. The diagnosis was confirmed by epidemiological, clinical, laboratory and radiological examinations. Among the 5 cases, 1 was a boy and the others were girls at the age of 4 to 13 years. RESULTS: Of the 5 SARS children, 3 presented a history of close contact with SARS patients. Fever was the initiative symptom, 4 had a body temperature of over 38 degrees C with the highest being 40 degrees C; fever sustained from 4 to 7 days with an average of 5.6 days. All the 5 cases developed nonproductive cough; on auscultation, both moist and dry rales could be heard in 3 out of the 5 cases. Mean total white count of peripheral blood was (2.96 - 6.9) x 10(9)/L, and was < 5.0 x 10(9)/L in 4 cases. SARS associated coronavirus specific RNA fragment was found positive by RT-PCR in 1 case; 1 case was positive for both IgM and IgG antibodies to the virus; 1 case was positive for only IgM antibody and another 2 cases were positive for only IgG antibody. IgG and IgM antibodies to Mycoplasma pneumoniae and Chlamydia pneumoniae as well as blood culture for bacteria were all negative. Findings on chest X-ray examination: 4 cases showed presence of patchy or macular opacities with cord-like shadows in unilateral lung plates while 1 case each showed ground-glass-like opacity and migratory changes; 1 case showed interstitial changes in the lungs in the form of irregular reticular lattice and cord-like shadows. Two cases received CT scanning and macular-patchy or spotty shadows were seen all over the lung. The shortest time for absorption of foci in the lungs was 7 days while the longest was 33 days with a mean of 15 +/- 6 days. None of the cases had any signs of fibrosis in the lungs. All the 5 cases were completely cured and discharged 7 to 40 days (mean 18 +/- 11 days) after admission. CONCLUSION: Compared with adult cases with SARS, children with SARS had milder symptoms and signs. Presence of unilateral patchy shadow in lungs represented the main chest X-ray findings.


Assuntos
Síndrome Respiratória Aguda Grave/virologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Adolescente , Anticorpos Antivirais/análise , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulina G/análise , Imunoglobulina M/análise , Masculino , Radiografia Torácica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia , Síndrome Respiratória Aguda Grave/diagnóstico por imagem , Síndrome Respiratória Aguda Grave/patologia
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