Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 78
Filtrar
1.
Emerg Microbes Infect ; 13(1): 2332670, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38646911

RESUMO

This study aimed to provide data for the clinical features of invasive pneumococcal disease (IPD) and the molecular characteristics of Streptococcus pneumoniae isolates from paediatric patients in China. We conducted a multi-centre prospective study for IPD in 19 hospitals across China from January 2019 to December 2021. Data of demographic characteristics, risk factors for IPD, death, and disability was collected and analysed. Serotypes, antibiotic susceptibility, and multi-locus sequence typing (MLST) of pneumococcal isolates were also detected. A total of 478 IPD cases and 355 pneumococcal isolates were enrolled. Among the patients, 260 were male, and the median age was 35 months (interquartile range, 12-46 months). Septicaemia (37.7%), meningitis (32.4%), and pneumonia (27.8%) were common disease types, and 46 (9.6%) patients died from IPD. Thirty-four serotypes were detected, 19F (24.2%), 14 (17.7%), 23F (14.9%), 6B (10.4%) and 19A (9.6%) were common serotypes. Pneumococcal isolates were highly resistant to macrolides (98.3%), tetracycline (94.1%), and trimethoprim/sulfamethoxazole (70.7%). Non-sensitive rates of penicillin were 6.2% and 83.3% in non-meningitis and meningitis isolates. 19F-ST271, 19A-ST320 and 14-ST876 showed high resistance to antibiotics. This multi-centre study reports the clinical features of IPD and demonstrates serotype distribution and antibiotic resistance of pneumococcal isolates in Chinese children. There exists the potential to reduce IPD by improved uptake of pneumococcal vaccination, and continued surveillance is warranted.


Assuntos
Antibacterianos , Tipagem de Sequências Multilocus , Infecções Pneumocócicas , Sorogrupo , Streptococcus pneumoniae , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Antibacterianos/farmacologia , China/epidemiologia , População do Leste Asiático , Hospitais/estatística & dados numéricos , Testes de Sensibilidade Microbiana , Infecções Pneumocócicas/microbiologia , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/mortalidade , Estudos Prospectivos , Fatores de Risco , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/isolamento & purificação
2.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(2): 131-138, 2024 Feb 15.
Artigo em Chinês | MEDLINE | ID: mdl-38436309

RESUMO

OBJECTIVES: To investigate the clinical characteristics and prognosis of pneumococcal meningitis (PM), and drug sensitivity of Streptococcus pneumoniae (SP) isolates in Chinese children. METHODS: A retrospective analysis was conducted on clinical information, laboratory data, and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country. RESULTS: Among the 160 children with PM, there were 103 males and 57 females. The age ranged from 15 days to 15 years, with 109 cases (68.1%) aged 3 months to under 3 years. SP strains were isolated from 95 cases (59.4%) in cerebrospinal fluid cultures and from 57 cases (35.6%) in blood cultures. The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87) and 27% (21/78), respectively. Fifty-five cases (34.4%) had one or more risk factors for purulent meningitis, 113 cases (70.6%) had one or more extra-cranial infectious foci, and 18 cases (11.3%) had underlying diseases. The most common clinical symptoms were fever (147 cases, 91.9%), followed by lethargy (98 cases, 61.3%) and vomiting (61 cases, 38.1%). Sixty-nine cases (43.1%) experienced intracranial complications during hospitalization, with subdural effusion and/or empyema being the most common complication [43 cases (26.9%)], followed by hydrocephalus in 24 cases (15.0%), brain abscess in 23 cases (14.4%), and cerebral hemorrhage in 8 cases (5.0%). Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old, with rates of 91% (39/43) and 83% (20/24), respectively. SP strains exhibited complete sensitivity to vancomycin (100%, 75/75), linezolid (100%, 56/56), and meropenem (100%, 6/6). High sensitivity rates were also observed for levofloxacin (81%, 22/27), moxifloxacin (82%, 14/17), rifampicin (96%, 25/26), and chloramphenicol (91%, 21/23). However, low sensitivity rates were found for penicillin (16%, 11/68) and clindamycin (6%, 1/17), and SP strains were completely resistant to erythromycin (100%, 31/31). The rates of discharge with cure and improvement were 22.5% (36/160) and 66.2% (106/160), respectively, while 18 cases (11.3%) had adverse outcomes. CONCLUSIONS: Pediatric PM is more common in children aged 3 months to under 3 years. Intracranial complications are more frequently observed in children under 1 year old. Fever is the most common clinical manifestation of PM, and subdural effusion/emphysema and hydrocephalus are the most frequent complications. Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates. Adverse outcomes can be noted in more than 10% of PM cases. SP strains are high sensitivity to vancomycin, linezolid, meropenem, levofloxacin, moxifloxacin, rifampicin, and chloramphenicol.


Assuntos
Empiema , Hidrocefalia , Meningite Pneumocócica , Derrame Subdural , Lactente , Feminino , Masculino , Humanos , Criança , Recém-Nascido , Adolescente , Meningite Pneumocócica/tratamento farmacológico , Meningite Pneumocócica/epidemiologia , Meropeném , Vancomicina , Levofloxacino , Linezolida , Moxifloxacina , Estudos Retrospectivos , Rifampina , Streptococcus pneumoniae , Cloranfenicol
3.
Int J Biol Macromol ; 260(Pt 2): 129690, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38266855

RESUMO

Radioactive iodine is considered one of the most dangerous radioactive elements in nuclear waste. Therefore, effective capture of radioactive iodine is essential for developing and using nuclear energy to solve the energy crisis. Some materials that have been developed for removing radioactive iodine still suffer from complex synthesis, low removal capacity, and non-reusability. Herein, covalent organic framework (COF)/chitosan (CS) aerogels were prepared using vacuum freeze-drying, and the COF nanoparticles were tightly attached on the green biomass material CS networks. Due to the synergistic effect of both COF and CS, the composite aerogel shows a three-dimensional porous and stable structure in the recycle usage. The COF/CS aerogel exhibits excellent iodine adsorption capacity of 2211.58 mg g-1 and 5.62 g g-1 for static iodine solution and iodine vapor, respectively, better than some common adsorbents. Furthermore, COF/CS aerogel demonstrated good recyclability performance with 87 % of the initial adsorption capacity after 5 cycles. In addition, the interaction between iodine and imine groups, amino groups, and benzene rings of aerogel are the possible adsorption mechanisms. COF/CS aerogel has excellent adsorption properties, good chemical stability, and reusable performance, which is a potential and efficient adsorbent for industrial radioactive iodine adsorption from nuclear waste.


Assuntos
Quitosana , Iodo , Estruturas Metalorgânicas , Resíduos Radioativos , Neoplasias da Glândula Tireoide , Humanos , Adsorção , Radioisótopos do Iodo
4.
Int J Biol Macromol ; 256(Pt 1): 128433, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38008141

RESUMO

With the exponentially increase of dye pollutants, the purification of dye wastewater has been an urgent ecological problem. As a novel type of porous adsorbent, metal-organic frameworks still face challenges in recyclability, agglomeration, and environmentally unfriendly synthesis. Herein, MOF-525 was in-situ growth onto the surface of the chitosan (CS) beads to fabricate MOF-525@CS aerogel. CS was utilized as substrate to uniformly disperse MOF-525, thereby significantly mitigating agglomeration and improving recyclability of MOF-525. The characterization results shown that MOF-525@CS aerogel had a high specific surface area of 103.0 m2·g-1, and MOF-525 was uniformly distributed in the 3D porous structure of CS, and the presence of benzoic acid was detected. The MOF-525@CS aerogel had a remarkable adsorption capacity of 1947 mg·g-1 for Congo red, which is greater than the sum of its parts. MOF-525@CS aerogel also inherited the rapid adsorption ability of MOF-525, removing 80 % of Congo red within 600 min. Such excellent adsorption performance can be attributed to the benzoic acid trapped by CS via CN band to enhance the π-π stacking interactions. Additionally, the utilization of benzoic acid makes the synthesis process of MOF-525@CS aerogel more environmentally friendly. The high-efficient MOF-525@CS aerogel is a competitive candidate for dye pollution adsorption.


Assuntos
Quitosana , Estruturas Metalorgânicas , Poluentes Químicos da Água , Vermelho Congo/química , Quitosana/química , Benzeno , Poluentes Químicos da Água/química , Cinética , Água , Adsorção , Ácido Benzoico
5.
J Colloid Interface Sci ; 656: 58-67, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37984171

RESUMO

Selective oxidations are important reactions in organic synthesis for fine chemical industry and conventional methods are expensive and produce a lot of toxic wastes. Herein, we demonstrate a facile and environmentally benign technique for liquid phase selective oxidation based on graphene-supported Mn single-atom-catalyst (SAMn-G) for efficient peroxymonosulfate (PMS) activation. The active Mn component in the developed SAMn-G catalyst reached single-atomic dispersion on graphene substrate via the coordination of individual Mn atoms with the doped N from the graphene framework. SAMn-G activated PMS via a nonradical-dominated pathway, which could convert aromatic alcohols into aldehydes or ketones at a mild temperature. The SAMn-G catalyst exhibited superior conversion and aldehyde selectivity in alcohol oxidation in comparison with their counterpart catalysts possessing either homogeneous Mn ions or oxide particles. The high activation efficiency of SAMn-G is due to the synergistic effect between Mn atoms and graphene substrate, as well as the dominated reaction pathway from nonradical oxidation, which is more selective than these free radicals to oxidize the alcohols. Concerted experimental evidence indicates that the non-radical oxidation process was highly possible to follow the electron transfer mechanism by PMS/organic adsorption on the surface of the catalyst. This study provides a fundamental understanding of PMS activation mediated by single atom catalyst for organic synthesis and the achieved insights can also help the catalyst design for other liquid phase selective oxidation processes.

6.
Int J Biol Macromol ; 253(Pt 5): 127155, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37783255

RESUMO

Micro- and nano-metal-organic frameworks with different adsorption properties were prepared by a time-modulation hydrothermal method. By comparing the adsorption properties, the most effective MIL-68(Fe)-12 was selected to be mixed with chitosan (CS), and porous metal-organic framework-acrylamide-chitosan composite aerogel (PMACA) was prepared by introducing acrylamide prior to glutaraldehyde crosslinking. The adsorption capacity of PMACA doped with acrylamide was as high as 2086.44 mg·g-1. The adsorption performance of PMACA was 1.48 times higher compared to the porous metal-organic framework-chitosan composite aerogel (PMCA) undoped with acrylamide. With the introduction of acrylamide, the stability of PMACA was improved, making it less prone to dispersion and decomposition. Structural characterization and adsorption properties were analyzed using methods such as XRD, FTIR, TGA, SEM, BET, and Zeta potential. The adsorption performance of PMACA was investigated further through batch tests with variables such as adsorbent dosage, pH, contact time, initial CR solution concentration, and temperature. The model fitting of PMACA was consistent with the pseudo-second-order model and the Sips model. The adsorption thermodynamics showed that high temperature promoted spontaneous adsorption behavior. PMACA showed a recovery rate of approximately 86 % after six cyclic adsorption tests. PMACA maintained a recovery rate of roughly 86 % after six cyclic adsorption tests. The combined effects of electrostatic attraction, hydrogen bonding, and π-π conjugation resulted in excellent adsorption performance, while pore filling also contributed to the efficient adsorption of Congo red (CR).


Assuntos
Quitosana , Estruturas Metalorgânicas , Poluentes Químicos da Água , Água , Quitosana/química , Adsorção , Compostos Azo , Porosidade , Concentração de Íons de Hidrogênio , Corantes , Acrilamidas , Poluentes Químicos da Água/química , Cinética
7.
BMC Pediatr ; 23(1): 496, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37784062

RESUMO

BACKGROUND: The presence of Staphylococcus aureus in the bloodstream can lead to the development of sepsis; however, the severity and risk factors of the systemic inflammatory response to Staphylococcus aureus bloodstream infections were unclear. This study is aimed to build a model to predict the risk of sepsis in children with Staphylococcus aureus bloodstream infections. METHODS: A retrospective analysis of hospitalized pediatric patients diagnosed with Staphylococcus aureus bloodstream infections was performed between January 2013 and December 2019. Each patient was assessed using the pediatric version of the Sequential Organ Failure Assessment score (pSOFA) within 24 h of blood culture collection. A nomogram based on logistic regression models was constructed to predict the risk factors for sepsis in children with Staphylococcus aureus bloodstream infections. It was validated using the area under the receiver-operating characteristic curve (AUC). RESULTS: Of the 94 patients included in the study, 35 cases (37.2%) developed sepsis. The pSOFA scores ranged from 0 to 8, with 35 patients having a pSOFA score of ≥ 2. Six children (6.4%) died within 30 days, who were all from the sepsis group and had different pSOFA scores. The most common organs involved in sepsis in children with staphylococcal bloodstream infections were the neurologic system (68.6%), respiratory system (48.6%), and coagulation system (45.7%). Hospital-acquired infections (adjusted odds ratio [aOR], 3.0; 95% confidence interval [CI], 1.3-7.2), implanted catheters (aOR, 10.4; 95% CI, 3.8-28.4), procalcitonin level ≥ 1.7 ng/mL (aOR, 15.4; 95% CI, 2.7-87.1), and underlying diseases, especially gastrointestinal malformations (aOR, 14.0; 95% CI, 2.9-66.7) were associated with Staphylococcus aureus sepsis. However, methicillin-resistant Staphylococcus aureus infection was not a risk factor for sepsis. The nomogram had high predictive accuracy for the estimation of sepsis risk, with an AUC of 0.85. CONCLUSIONS: We developed a predictive model for sepsis in children with Staphylococcus aureus infection.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Sepse , Infecções Estafilocócicas , Humanos , Criança , Staphylococcus aureus , Estudos Retrospectivos , Sepse/complicações , Sepse/diagnóstico , Infecções Estafilocócicas/complicações , Infecções Estafilocócicas/diagnóstico
8.
Int J Biol Macromol ; 253(Pt 3): 126967, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37722644

RESUMO

In this paper, a kind of magnetic ferric oxide/polyvinyl alcohol/calcium alginate/UiO-67 (Fe3O4/PVA/CA/UiO-67) nanospheres with homogeneous surface interconnecting structures was prepared by using macromolecular polymer polyvinyl alcohol and sodium alginate as carriers and zirconium organic skeleton as nanocrystals. The properties of magnetic nanospheres were studied by SEM, FT-IR, TGA, XRD, BET, VSM and Zeta potential. The impression of diverse temperatures, MB concentrations, interaction time, pH, and magnetic aerogel sphere dose on MB removal was studied. The optimum adsorption temperature and pH of magnetic nanospheres for MB were 298 K, and 10, respectively. Langmuir simulated that the maximum removal of MB by magnetic nanospheres at room temperature (298 K) was 1371.8 mg/g. The removal of MB by magnetic nanospheres complied with the pseudo-first-order kinetic model. The isotherm simulation can infer that the Langmuir model was more comply with MB adsorption on magnetic aerogel spheres. Thermodynamic studies have confirmed that the removal of MB by magnetic nanospheres was exothermic and spontaneous. The interaction mechanism of MB on magnetic nanospheres can be deduced by FT-IR and BET, including hydrogen bond, π-π bond, electrostatic interaction, and mesoporous pore flow. The removal rate of nanospheres for MB still reached 70.06 % after six cycles.


Assuntos
Nanosferas , Poluentes Químicos da Água , Óxidos , Adsorção , Azul de Metileno/química , Álcool de Polivinil , Alginatos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Fenômenos Magnéticos , Poluentes Químicos da Água/química , Cinética
9.
Int J Biol Macromol ; 253(Pt 1): 126458, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37619681

RESUMO

This paper presents the first investigation of the adsorption performance of methylene blue by the nitro-functionalized metal-organic framework (MIL-88B-NO2). MIL-88B-NO2 has a specific surface area of 836.0 m2/g, which is 109.8 % higher than MIL-88B. The maximum adsorption capacity of methylene blue is 383.6 mg/g, which is 68.2 % higher than that of MIL-88B. This phenomenon can be attributed to the great increase in specific surface area and the introduction of nitro-functional groups. However, its microcrystalline nature makes it difficult to remove in practical applications and quickly causes secondary pollution. Therefore, the composite of MIL-88B-NO2 and calcium alginate (CA) to form aerogel maintains the inherent properties of the two materials and makes it easy to recycle. The utmost adsorption capability of MIL-88B-NO2/CA-2 aerogel is 721.0 mg/g. Compared with MIL-88B-NO2, the adsorption performance of MIL-88B-NO2/CA-2 aerogel is further improved by 88.0 %. The higher adsorption capacity of the adsorbent may be due to the synergistic interplay of electrostatic attraction, π-π conjugation, hydrogen bonding, metal coordination effect, and physicochemical properties. Also, MIL-88B-NO2/CA-2 aerogel has good recyclability, indicating that it has broad application prospects in the removal of positive dyes in contaminated water.


Assuntos
Azul de Metileno , Água , Adsorção , Água/química , Dióxido de Nitrogênio , Metais , Compostos Radiofarmacêuticos , Esqueleto
10.
Nat Commun ; 14(1): 4670, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37537180

RESUMO

Electrochemical conversion of CO2 to formic acid using Bismuth catalysts is one the most promising pathways for industrialization. However, it is still difficult to achieve high formic acid production at wide voltage intervals and industrial current densities because the Bi catalysts are often poisoned by oxygenated species. Herein, we report a Bi3S2 nanowire-ascorbic acid hybrid catalyst that simultaneously improves formic acid selectivity, activity, and stability at high applied voltages. Specifically, a more than 95% faraday efficiency was achieved for the formate formation over a wide potential range above 1.0 V and at ampere-level current densities. The observed excellent catalytic performance was attributable to a unique reconstruction mechanism to form more defective sites while the ascorbic acid layer further stabilized the defective sites by trapping the poisoning hydroxyl groups. When used in an all-solid-state reactor system, the newly developed catalyst achieved efficient production of pure formic acid over 120 hours at 50 mA cm-2 (200 mA cell current).

11.
Int J Biol Macromol ; 252: 126198, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37586626

RESUMO

Micro-nano metal-organic framework (MIL-68(Fe)) for efficient adsorption of azo anionic dye Congo red (CR) was successfully prepared by one-step hydrothermal method under acidic environment. And a MIL-68(Fe)/chitosan composite sponge (MIL-68(Fe)/CS) was prepared under the coating of chitosan (CS). After comparing the performance of MIL-68(Fe) and MIL-68(Fe)/CS, we focus on exploring MIL-68(Fe)/CS. It ensured the CR removal efficiency while reaching the adsorption equilibrium faster than MIL-68(Fe), and solved the defect that the powder was difficult to be stripped by water after adsorption. The physicochemical properties and surface morphology of the adsorbent were characterized by SEM, FTIR, XRD, TGA, BET, and Zeta potential. The effects of pH, contact time, adsorbent dosage, initial solution concentration and temperature on the adsorption performance of the adsorbent were systematically analyzed. The pseudo-second-order model and the Sips model were most consistent for the adsorption process, indicating that the adsorption process of MIL-68(Fe)/chitosan composite sponge on CR is a complex physicochemical process. The removal rates of CR by MIL-68(Fe) and MIL-68(Fe)/chitosan composite sponge reached the maximum values of 99.55 % and 99.51 % at 318 K, respectively. And the maximum adsorption capacity of CR by MIL-68(Fe)/chitosan composite sponge at 318 K was 1184.16 mg·g-1. After six cycles of adsorption and desorption, the removal rate of CR was still higher than 80 %. The synergistic effects of π-π stacking, electrostatic interactions, hydrogen bonding and pore filling have important effects on CR removal.


Assuntos
Quitosana , Estruturas Metalorgânicas , Poluentes Químicos da Água , Vermelho Congo , Quitosana/química , Adsorção , Compostos Azo , Poluentes Químicos da Água/química , Cinética , Concentração de Íons de Hidrogênio
12.
Langmuir ; 39(30): 10611-10624, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37470723

RESUMO

In this paper, the physicochemical properties, surface charge, and crystal defects of MIL-88A (Al) were controlled by adjusting the ratio of metal ligands and temperature in the synthetic system without the addition of surfactants. The adsorption properties of different crystals for Congo red (CR) were studied. Among them, MIL-88A (Al)-130 and MIL-88A (Al)-d have the best adsorption properties. The maximum adsorption capacities are 600.8 and 1167 mg · g-1, respectively. Compared with MIL-88A (Al)-130, the adsorption performance of MIL-88A (Al)-d was increased by 94.2%, and the adsorption rate was increased by about 4 times. It can be seen that increasing the proportion of metal ligands within a certain range will improve the adsorption capacity. The structure and morphology of the adsorbent were characterized by XRD, FTIR, SEM, EDS, TGA, BET, and zeta potential. The effects of time, temperature, pH, initial solution concentration, and dosage on CR adsorption properties were systematically discussed. The pseudo-second-order kinetic model and Langmuir isothermal model can well describe the adsorption process, which indicates that the adsorption process is a single-layer chemisorption occurring on a uniform surface. According to thermodynamics, this adsorption is an endothermic process. The mechanism of CR removal is proposed as the electrostatic attraction, hydrogen bond, metal coordination effect, π-π conjugation, crystal defect, and pore-filling effect. In addition, MIL-88A (Al)-d has good repeatability, indicating that it is a good material for treating anionic dye wastewater.

13.
J Biophotonics ; 16(10): e202200366, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37289020

RESUMO

Optical coherence tomography angiography (OCTA) in dermatology usually suffers from low image quality due to the highly scattering property of the skin, the complexity of cutaneous vasculature, and limited acquisition time. Deep-learning methods have achieved great success in many applications. However, the deep learning approach to improve dermatological OCTA images has not been investigated due to the requirement of high-performance OCTA systems and difficulty of obtaining high-quality images as ground truth. This study aims to generate proper datasets and develop a robust deep learning method to enhance the skin OCTA images. A swept-source skin OCTA system was employed to create low-quality and high-quality OCTA images with different scanning protocols. We propose a model named vascular visualization enhancement generative adversarial network and adopt an optimized data augmentation strategy and perceptual content loss function to achieve better image enhancement effect with small amount of training data. We demonstrate the superiority of the proposed method in skin OCTA image enhancement by quantitative and qualitative comparisons.


Assuntos
Aprendizado Profundo , Dermatologia , Tomografia de Coerência Óptica/métodos , Angiografia , Pele/diagnóstico por imagem
14.
Int J Biol Macromol ; 242(Pt 1): 124683, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37141973

RESUMO

A chitosan/alginate/graphene oxide/UiO-67 (CS/SA/GO/UiO-67) amphoteric aerogel was synthesized successfully. A series of characterization experiments of CS/SA/GO/UiO-67 amphoteric aerogel was performed by SEM, EDS, FT-IR, TGA, XRD, BET, and zeta potential. The competitive adsorption properties of different adsorbents for complex dyes wastewater (MB and CR) at room temperature (298 K) were compared. Langmuir isotherm model predicted that the maximum adsorption quantity of CS/SA/GO/UiO-67 for CR and MB was 1091.61 and 1313.95 mg/g, respectively. The optimum pH values of CS/SA/GO/UiO-67 for the adsorption of CR and MB were 5 and 10, respectively. The kinetic analysis showed that the adsorption of MB and CR on CS/SA/GO/UiO-67 was more suitable for the pseudo-second-order and pseudo-first-order kinetic model, respectively. The isotherm study revealed that the adsorption of MB and CR was consistent with the Langmuir isotherm model. The thermodynamic study demonstrated that the adsorption process of MB and CR was exothermic and spontaneous. FT-IR analysis and zeta potential characterization experiments revealed that the adsorption mechanism of MB and CR on CS/SA/GO/UiO-67 depended on π-π bond, hydrogen bond, and electrostatic attraction. Repeatable experiments showed that the removal rates of MB and CR of CS/SA/GO/UiO-67 after six cycles of adsorption were 67.19 and 60.82 %, respectively.


Assuntos
Quitosana , Corantes , Corantes/química , Quitosana/química , Espectroscopia de Infravermelho com Transformada de Fourier , Adsorção , Alginatos , Cinética
15.
Int J Biol Macromol ; 238: 124044, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-36933588

RESUMO

Zirconium alginate/graphene oxide (ZA/GO) hydrogel spheres were prepared by crosslinking sodium alginate and GO with Zr4+. Then Zr4+ on the surface of the ZA/GO substrate acted as the metal nucleation site of the UiO-67 crystal and interacted with the organic ligand biphenyl 4-4'-dicarboxylic acid (BPDC) to make UiO-67 grow in situ on the surface of the ZA/GO hydrogel sphere by the hydrothermal method. The BET surface areas of ZA/GO, ZA/UiO-67, and ZA/GO/UiO-67 aerogel spheres were 1.29, 47.71, and 89.33 m2/g respectively. The maximum adsorption capacities of ZA/GO, ZA/UiO-67, and ZA/GO/UiO-67 aerogel spheres for methylene blue (MB) at room temperature (298 K) were 145.08, 307.49, and 1105.23 mg/g respectively. The kinetic analysis showed that the adsorption process of MB on the ZA/GO/UiO-67 aerogel sphere was consistent with the pseudo-first-order kinetic model. Isotherm analysis showed that MB was adsorbed on ZA/GO/UiO-67 aerogel spheres as a single layer. Thermodynamic analysis showed that the adsorption process of MB on the ZA/GO/UiO-67 aerogel sphere was exothermic and spontaneous. Adsorption of MB on ZA/GO/UiO-67 aerogel spheres is mainly dependent on π-π bond, electrostatic interaction, and hydrogen bond. After 8 cycles, ZA/GO/UiO-67 aerogel spheres still showed high adsorption performance and good reuse ability.


Assuntos
Grafite , Poluentes Químicos da Água , Azul de Metileno/química , Cinética , Adsorção , Alginatos/química , Poluentes Químicos da Água/química , Grafite/química , Hidrogéis
17.
Int J Biol Macromol ; 239: 124157, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36965569

RESUMO

MIL-88A crystals with three different metal ligands (Fe, Al, FeAl) were prepared by hydrothermal method for the first time. The three materials' crystal structure and surface morphology are different, leading to different adsorption properties of Congo red (CR). The maximum adsorption capacities of MIL-88A (Fe), MIL-88A (FeAl), and MIL-88A (Al) are 607.7 mg · g-1, 536.4 mg · g-1, and 512.1 mg · g-1 respectively. In addition, MIL-88A was combined with chitosan (CS) respectively, and MIL-88A/CS composite sponge was prepared by the freeze-drying method, which not only solved the defect that MIL-88A powder was difficult to recover but also further improved the removal ability of CR by the adsorbent. The maximum adsorption capacities of MIL-88A (FeAl)/CS, MIL-88A (Fe)/CS, MIL-88A (Al)/CS, and CS are 1312 mg · g-1, 1056 mg · g-1, 996.7 mg · g-1, and 769.6 mg · g-1, respectively. The structure and physicochemical properties of the materials were analyzed by SEM, FTIR, XRD, TGA, BET, and Zeta. The adsorption process of CR follows pseudo-second-order kinetics and Langmuir, Sips isotherm model. Combined with thermodynamic parameters, the adsorption behavior was described as endothermic monomolecular chemical adsorption. The removal of CR is attributed to electrostatic interactions, hydrogen bonding, metal coordination effects, and size-matching effects.


Assuntos
Quitosana , Poluentes Químicos da Água , Vermelho Congo , Quitosana/química , Adsorção , Termodinâmica , Poluentes Químicos da Água/química , Cinética
18.
J Inflamm Res ; 16: 321-331, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36726792

RESUMO

Purpose: Heparin-binding protein (HBP) is a novel biomarker for inflammatory diseases. This study aimed to investigate the role of serum HBP in community-acquired pneumonia (CAP) in children and the association of HBP with the severity and prognosis. Patients and Methods: A total of 125 children with CAP admitted to the hospital were enrolled in this retrospective study. We analyzed the differences in clinical characteristics and examination findings between patients with different levels of HBP. The severe or complicated CAP was defined as having severe radiographic findings and/or systemic manifestations. Receiver operator characteristic (ROC) curves detected the performance of biomarkers in identifying patients with severe or complicated pneumonia. The multivariate logistic regression models assessed the association between HBP levels and the severity and prognosis. Finally, we constructed a predictive model based on HBP. Results: The rate of severe or complicated CAP for patients with upper-quartile HBP concentration (≥60 ng/mL) was 54.8%, significantly higher than that of patients with lower HBP concentration (26.6%). The level of HBP is substantially correlated with neutrophil counts, C-reactive protein, erythrocyte sedimentation rate, and serum amyloid A protein (r = 0.31, 0.26, 0.36, and 0.26, respectively). HBP achieved the highest level of discrimination for severe or complicated CAP among the biomarkers. Higher HBP concentration (≥60 ng/mL) was associated with a three-fold higher risk of severe or complicated CAP (adjusted odds ratio = 3.11, p < 0.05). A predictive model including four characteristics (HBP, lactate dehydrogenase, age and non-viral infection) for predicting severe or complicated CAP (with area under the ROC curve = 0.75) was built to create a nomogram. Conclusion: Substantially elevated serum HBP is significantly associated with severe or complicated CAP and poor prognosis in children. This finding warrants further investigation of the function of HBP in the pathogenesis of CAP.

19.
ACS Omega ; 8(1): 857-867, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36643493

RESUMO

In this study, composite hydrogels were prepared using a simple synthetic technique to adsorb methylene blue (MB) from water. The hydrogel comprised potassium persulfate (KPS) as the initiator, N,N'-methylene bisacrylamide as the crosslinking agent, and sodium hydroxide (NaOH) as the activator. It was employed to adsorb MB at different concentrations from water. The morphology and properties of PUL/PAM/GO composites were characterized through thermogravimetric analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. Moreover, the adsorption properties, adsorption isotherms, adsorption kinetics, adsorption thermodynamics, and swelling properties of the hydrogel for MB were investigated. The optimal ratio of PUL to AC was obtained as 6:1 by fixing the amount of PUL and loading AC of different masses. The maximum adsorption capacity was obtained as 591.4 mg/g. It also exhibited certain mechanical strength. The adsorption of MB conforms to pseudo-first-order kinetics and Langmuir isotherms. In this study, an environment-friendly, cheap, simple, and efficient way was presented for the composite hydrogel in the direction of water treatment.

20.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(10): 1092-1097, 2022 Oct 15.
Artigo em Chinês | MEDLINE | ID: mdl-36305108

RESUMO

OBJECTIVES: To study the clinical features of children infected with the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: The medical data of 19 children who were diagnosed with SARS-CoV-2 Omicron variant infection from January 28 to March 3, 2022 in Hangzhou were retrospectively reviewed. RESULTS: Among the 19 children, there were 7 boys (37%) and 12 girls (63%), and their age ranged from 6 months to 16 years, with a median age of 2 years and 1 month. Most of these children were infants and young children (aged ≤3 years, accounting for 53%). Among these children, 11 (58%) were unvaccinated with SARS-CoV-2 vaccine and 8 (42%) were vaccinated with SARS-CoV-2 vaccine, and 3 children (16%) had a history of underlying diseases. All 19 children had a clear history of close contact with persons infected with SARS-CoV-2, and 10 children (53%) were involved in the cluster outbreak in a maternal and infant care center. In terms of clinical classification, 13 children (68%) had mild coronavirus disease 2019 (COVID-19) and 6 (32%) had common COVID-19, with no severe cases of COVID-19. The most common clinical symptoms were cough (100%) and fever (63%). The children with a normal peripheral white blood cell count accounted for 84%, and those with a normal lymphocyte count accounted for 68%. There were no significant abnormalities in platelet count, procalcitonin, liver function parameters (alanine aminotransferase and aspartate aminotransferase), and renal function parameters (creatinine and urea). Six children (32%) had obvious signs of pneumonia on chest CT. All 19 children were given symptomatic treatment, and 12 children (63%) were given aerosol inhalation of interferon α. All children were cured and discharged. CONCLUSIONS: Children infected with Omicron variant strains are more common in infants and young children, with mild symptoms and good prognosis. Most of the children have a history of close contact with persons infected with SARS-CoV-2, and epidemic prevention and control should be strengthened in places with many infants and children, such as maternal and infant care centers.


Assuntos
COVID-19 , SARS-CoV-2 , Criança , Lactente , Masculino , Feminino , Humanos , Pré-Escolar , Estudos Retrospectivos , Vacinas contra COVID-19 , China/epidemiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...