Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
BMC Psychiatry ; 23(1): 862, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37990311

RESUMO

BACKGROUND: Obsessive Compulsive Disorder (OCD) symptoms, are among the serious mental health challenges that Health Care Workers (HCWs) faced during the COVID-19 pandemic. As these symptoms reduce the mental well-being and effectiveness of HCWs which are followed by poor health outcomes for patients, the aim of this systematic review and meta-analysis was to determine the prevalence of OCD symptoms among HCWs worldwide. METHODS: PubMed, Google Scholar, Cochrane, Scopus, Web of Science, ProQuest, Emerald, and ERIC databases were searched using related keywords till the end of October 2021. Observational studies about the prevalence of OCD symptoms among healthcare workers during the COVID-19 pandemic were screened and evaluated. In order to assess the quality of studies, the Newcastle-Ottawa scale (NOS) checklist was used. The effect measure was the prevalence rate with a 95% confidence interval (CI). RESULTS: A total of 7864 individuals from 11 studies were included. The range of OCD symptoms prevalence across these studies was from 0.07 to 0.47. Due to the high heterogeneity between the studies (I2 = 98.6%, P < 0.01), the random effects model was used. The pooled prevalence was 0.29 (95% CI: 0.22-0.38) based on logit transformed CI. CONCLUSIONS: The pooled prevalence of OCD symptoms was 29% among the HCWs during the COVID-19 pandemic. This prevalence was higher than the general population according to the pre-pandemic literature, but lower than the recent reports amid the pandemic. Psychosocial interventions are suggested to be designed and implemented in such conditions.


Assuntos
COVID-19 , Transtorno Obsessivo-Compulsivo , Humanos , COVID-19/epidemiologia , Pandemias , Prevalência , Transtorno Obsessivo-Compulsivo/diagnóstico , Transtorno Obsessivo-Compulsivo/epidemiologia , Transtorno Obsessivo-Compulsivo/psicologia , Pessoal de Saúde
2.
Environ Technol ; 44(21): 3215-3228, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35298360

RESUMO

Production of concentrated polyaluminum chloride (PACl) with the proper distribution of Al species (Ala, Alb, and Alc) is still a challenging issue on both industrial and laboratory scale. Hence, the effects of total aluminum concentration (AlT) at high levels, regular basicity values, and low base injection rates on the distribution of Al species in PACl solutions were investigated using quadratic models. The results confirmed the possibility to synthesize tailor-made PACl solutions with a specified value of either Ala, Alb, or Alc within the range of 22-51%, 4-51%, or 0.5-74%, respectively. For instance, in agreement with the predicted value, a PACl sample rich in both Alb (42,200 ppm) and AlT was produced by applying the basicity of 1.7, AlT of 9.07% as Al2O3, and basification rate of 0.48 ml/h. In addition, the maximum Alc could be acquired by exploiting the highest C, B, and Q values. This condition also minimized both Ala and Alb. The trends of Ala and Alc changes by the increment of basicity were concave and convex, respectively, while Alb showed either a decreasing trend or a concave pattern based on the values of injection rate and AlT. The Alb-rich PACl sample was effectively applied for turbidity removal from synthetic wastewater at various pHs and initial turbidities. At best, residual turbidity of about 1% was observed after the coagulation process. These findings can be constructive for the production and application of tailor-made PACl.


Assuntos
Hidróxido de Alumínio , Purificação da Água , Alumínio , Águas Residuárias , Floculação
3.
Reprod Sci ; 30(6): 1823-1833, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36512189

RESUMO

Polycystic ovary syndrome (PCOS) is a common condition in reproductive-aged women that induces reproductive and metabolic derangements. Women with PCOS seem to have disturbances in lipid metabolism in the adipose tissue. Nevertheless, gene expression in adipose tissue of PCOS women and its relation to other disturbances have been fragmentarily investigated. We utilized microarray data to identify the most important up- and down-regulated candidate genes in adipose tissue of PCOS women in contrast to healthy women using the meta-analysis technique. Microarray data produced from three independent experiments (n = 3) conducted on adipose tissue in women with PCOS were retrieved from ArrayExpress. Then, the datasets were merged using the metaSeq package in Rstudio and differentially expressed genes (DEGs) were selected in the studies. The integrative bioinformatics analyses of candidate genes were performed by gene ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, and protein-protein interaction (PPI) network construction. Of these, 12 up-regulated genes and 12 down-regulated genes were identified and assessed as the most highly up-regulated and down-regulated genes in adipose tissue of women with PCOS. These DEGs that were annotated by KEGG analysis were mainly involved in PI3K-Akt, MAPK, Rap1, and Ras signaling pathways, and pathways in cancer such as hepatocellular carcinoma and gastric cancer, as well as metabolic pathways, and brain disorder pathways such as Alzheimer's disease and Huntington disease pathways. In the PPI networks, PRDM10, FGFR2, IGF1R, and FLT1 were the key nodes in the up-regulated networks, while the NDUFAB1 and NME2 proteins were key in the down-regulated networks. Overall, these findings provide insight into the gene expression in adipose tissue of PCOS women and its relation to other disturbances.


Assuntos
Síndrome do Ovário Policístico , Transcriptoma , Humanos , Feminino , Adulto , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Redes Reguladoras de Genes , Perfilação da Expressão Gênica , Tecido Adiposo/metabolismo , Biologia Computacional/métodos
4.
Prep Biochem Biotechnol ; 52(4): 375-382, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34319847

RESUMO

In the present study, the production of cellulase by Trichoderma reesei under solid-state fermentation of nettle biomass was promoted through supplementation of the culture media using carbonaceous additives and comprehensive optimization of the cultivation via the Taguchi method. CMCase activities about 5.5-6.1 U/gds were obtained by fermentation of the autoclave-pretreated biomass, among various chemical and physical pretreatments. Then, several additives including Tween 80, betaine, carboxymethyl cellulose, and lactose were individually or in combination added to the culture media to induce the enzyme production. The results proved that such additives could act as either inducers or inhibitors. Furthermore, CMCase activity surprisingly increased to 14.0 U/gds by supplementing the fermentation medium with the optimal mixture of additives including 0.08 mg/gds Tween 80, 0.4 mg/gds betaine, and 0.2 mg/gds carboxymethyl cellulose. Factor screening according to Plackett-Burman design confirmed that the levels of Urea and MgSO4 among basal medium constituents as well as pH of the medium were significantly affected CMCase production. By optimizing the levels of these factors, CMCase activity of 18.8 U/gds was obtained, which was noticeably higher than that of fermentation of the raw nettle. The applied procedure can be promisingly used to convert the nettle biomass into valuable products.


Assuntos
Celulase , Trichoderma , Betaína , Biomassa , Carboximetilcelulose Sódica , Meios de Cultura , Suplementos Nutricionais , Fermentação , Hypocreales , Polissorbatos
5.
Biomedicine (Taipei) ; 11(3): 5-14, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35223405

RESUMO

INTRODUCTION: As the COVID-19 pandemic ravages the world, nursing resources, and capacities play an essential role in disease management. This literature review focuses on the central issues related to the nursing care of patients affected by COVID-19. MATERIAL AND METHODS: This literature review was conducted with an extensive search of databases, including PubMed, Web of Science (WOS), and Scopus, using the keywords "COVID19", "2019-nCoV disease", "2019 novel coronavirus infection", "Nurse", "NursingCare", and" Nursing management." The span of the literature search was between December 01, 2020, and January 12, 2021. A total of 28 original and English-language articles were selected for inclusion in the review. RESULTS: Nursing interventions such as monitoring, oxygen therapy, and the use of Extra Corporeal Membrane Oxygenation (ECMO) in the care of COVID-19 patients, caring for ICU patients with COVID-19, rehabilitation of COVID-19 patients, nurses' experiences and barriers in the care of patients with COVID-19, and also the ethical challenges in the care of patients with COVID-19, were found to be valuable in managing COVID-19 patients. CONCLUSION: Nurses have a pivotal role to play in the care of patients with COVID-19. Therefore, providing comprehensive and quality nursing care supported by experience and research is necessary to successfully reduce the length of hospital stay and decrease the morbidity and mortality rates of COVID-19.

6.
Bioresour Bioprocess ; 8(1): 69, 2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-38656091

RESUMO

Development of cationic flocculants from lignocellulosic wastes not only eliminates the health and environmental concerns associated with the use of conventional chemicals, but also is the way of waste valorization. In the present study, cellulose fibers extracted from rice husk were cationized through an optimization method based on response surface methodology. The fibers cationized at the optimal conditions had a zeta-potential of 15.2 ± 1.0 mV, while the highest potential was + 8.76 mV, for the samples developed before optimization. FTIR analysis proved the presence of the corresponding functional groups. The functionalized fibers were biodegradable and had absolutely positive surface charges at a broad pH range. The cationized fibers were employed as a flocculant to remove turbidity from the synthetic wastewaters at various pHs and initial turbidities. The cationic fibers showed the excellent turbidity removals up to 98.5% from the synthetic wastewater without the need for conventional coagulants. In contrast to traditionally cationized fibers, the synthesized flocculants did not affect the effluent color during coagulation-flocculation. The charge neutralization and bridging through adsorption were the governing mechanisms of flocculation. The procedure can be applied on lignocellulosic wastes to develop cationic fibers with the excellent flocculation ability and suitable operational characteristics.

7.
J Environ Manage ; 255: 109939, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31790872

RESUMO

Conventional flocculants bear environmental and health concerns which could be avoided by applying natural materials, particularly polysaccharide and glycoprotein-containing ones. In the present study, yeast cell wall (YCW), a natural polymer matrix, was used as natural flocculant. To prepare YCW, Saccharomyces cerevisiae was cultivated in bench scale fermenter. After characterization, YCW was employed as anionic flocculant in jar tests to remove turbidity from kaolin suspensions at different conditions where either alum or poly aluminum chloride (PAC) was coagulant. Generally, the lower coagulant consumption, higher turbidity removal or faster sedimentation was observed by using YCW as flocculant. The developed flocculant was more effective in the presence of PAC compared to alum. At best, by applying 300 mg/L YCW, the highest turbidity removals of 98 and 97% were achieved using 10 ppm PAC at pH 6.5 and 50 ppm alum at pH 7.5, respectively. The presence of the flocculant in the structure of the flocs was proved by FTIR analysis. The final pH of the treated suspensions was suitable for discharge purpose without the need for neutralization. The excess positive charge neutralization and bridging were the governing mechanism in coagulation-flocculation process. YCW with proper performance, GRAS designation and readily availability can be considered as natural alternative to chemical anionic flocculants where the process needs safe compounds.


Assuntos
Caulim , Purificação da Água , Ânions , Floculação , Polímeros , Suspensões
8.
J Biol Inorg Chem ; 24(7): 943-959, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31359184

RESUMO

Immobilized tyrosinase onto the functionalized nanoparticles with the ability to be reused easily in different reaction cycles to degrade phenolic compounds is known as a substantial challenge, which can be overcome through surface modification of the particles via proper chemical groups. Herein, the synthesis and silica coating of superparamagnetic nanoparticles using a simple procedure as well as their potential for tyrosinase immobilization were demonstrated. Therefore, N-[3-(trimethoxysilyl)propyl]ethylenediamine was used to functionalize the silica-coated nanoparticles with amine groups. Then, the ethylenediamine functionalized magnetic nanoparticles (EMNPs) were suspended in a solution containing tetrahydrofuran and cyanuric chloride (as an activating agent) to modify nanocarriers. To immobilize enzyme, a mixture of tyrosinase and cyanuric chloride functionalized magnetic nanoparticle (Cyc/EMNPs) was shaken at room temperature. The particles were characterized by EDX, TGA, SEM, FTIR, and TEM. As a result, the successful functionalization of the magnetic nanoparticles and covalent attachment of tyrosinase onto the Cyc/EMNPs were confirmed. The fabricated nano-biocatalyst particles were semi-spherical in shape. The immobilized tyrosinase (Ty-Cyc/EMNPs) exhibited remarkable reusability of six consecutive reaction cycles while no considerable loss of activity was observed for the first three cycles. Moreover, the excellent stability of the biocatalyst at different temperatures and pHs was proved. The Ty-Cyc/EMNPs with interesting features are promising for practical applications in biosensor development and wastewater treatment.


Assuntos
Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Enzimas , Etilenodiaminas/química , Nanopartículas de Magnetita/química , Monofenol Mono-Oxigenase/química , Monofenol Mono-Oxigenase/metabolismo , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Fenol/isolamento & purificação , Fenol/metabolismo , Temperatura
9.
Biodegradation ; 30(1): 59-69, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30600422

RESUMO

Rhamnolipids are one of the most well-known classes of biosurfactants having wide applications in various industries due to low toxicity, high biodegradability, and environmentally friendly. Dissolved oxygen (DO) concentration has the crucial effect on rhamnolipids production, particularly through fed-batch cultivation. In this study, the effect of different levels of DO concentrations on rhamnolipid production by Pseudomonas aeruginosa in both batch and fed-batch fermentation was investigated in a lab-scale fermenter under precise DO control. A maximal rhamnolipid production of 22.5 g/l was obtained at a DO concentration of 40% in batch fermentation. In order to achieve the high rhamnolipid production, a fed-batch operation under tight DO control of 40% was conducted. As a result, the overall rhamnolipid production and productivity reached to 240 g/l and 0.9 (g/l h), corresponding to a 10.7 and 4.8-fold improvement compared to the batch experiments. The high level of rhamnolipid production via the fed-batch cultivation can be attributed to both DO concentration and the feeding strategy. This achievement is promising for the production of rhamnolipid in industrial scale.


Assuntos
Técnicas de Cultura Celular por Lotes/instrumentação , Técnicas de Cultura Celular por Lotes/métodos , Reatores Biológicos/microbiologia , Glicolipídeos/biossíntese , Oxigênio/farmacologia , Pseudomonas aeruginosa/metabolismo , Biodegradação Ambiental , Biomassa , Fermentação , Glicolipídeos/química , Concentração de Íons de Hidrogênio , Pseudomonas aeruginosa/efeitos dos fármacos , Solubilidade
10.
3 Biotech ; 8(10): 419, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30305990

RESUMO

Low conversion efficiency and long-processing time are some of the major problems associated with the use of biocatalysts in industrial processes. In this study, modified magnetic iron oxide nanoparticles bearing tyrosinase (tyrosinase-MNPs) were employed as a magnetic nano-biocatalyst to treat phenol-containing wastewater. Different factors affecting the phenol removal efficiency of the fabricated nano-biocatalyst such as catalyst dosage, pH, temperature, initial phenol concentration, and reusability were investigated. The results proved that the precise dosage of nano-biocatalyst was able to degrade phenol at the wide range of pHs and temperatures. The immobilized tyrosinase showed proper phenol degradation more than 70%, where the substrate with a high concentration of 2500 mg/L was subjected to phenol removal. The nano-biocatalyst was highly efficient and reusable, since it displayed phenol degradation yields of 100% after the third reuse cycle and about 58% after the seventh cycle. Moreover, the immobilized tyrosinase was able to degrade phenol dissolved in real water samples up to 78% after incubation for 60 min. It was also reusable at least seven cycles in the real water sample. The results proved the effectiveness and applicability of the fabricated nano-biocatalyst to treat phenol-containing wastewaters in a shorter time and higher efficiency even at high phenol concentration. The developed nano-biocatalyst can be promising for the micropollutants removal and an alternative for the catalysts used in traditional treatment processes.

11.
Int J Biol Macromol ; 94(Pt A): 396-405, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27771406

RESUMO

Magnetic nanoparticles (MNPs) were synthesized using the chemical co-precipitation method. Then the nanoparticles were coated with silica via hydrolysis of tetraethyl orthosilicate using the sol-gel process. The silica coated magnetic nanoparticles were amine-functionalized with 3-aminopropyltriethoxysilane/ethanol solution. Subsequently, the nanoparticles were added to a solution of cyanuric chloride in tetrahydrofuran to synthesize cyanuric chloride-functionalized magnetic nanoparticles (Cy-MNPs). For covalent immobilization of tyrosinase, Cy-MNPs were added to a freshly prepared tyrosinase solution and the mixture was shaken. The FTIR spectra, as well as EDX, analysis proved the covalent immobilization of tyrosinase on the nanoparticles. The magnetic properties of tyrosinase-immobilized magnetic nanoparticles (tyrosinase-MNPs) were specified by VSM analysis. TEM images indicated that the most of the tyrosinase-MNPs had a semi-spherical shape with an average size of 17nm. The synthesized nanoparticles had a high loading capacity of 194mg tyrosinase/g nanoparticles with an immobilization yield of 69%. The optimum condition for both free and immobilized tyrosinase was found at pH 7.0 and 35°C. The immobilized enzyme was active after treatment of the particles at various pHs and temperatures for 100min. In addition, reusability of the immobilized enzyme was investigated and it was proved its suitability to be used for more than 7 cycles. Also, tyrosinase-MNPs remained about 70% of its initial activity after storing at 4°C for 40days. This nanobiocatalyst with interesting properties is promising for practical application in wastewater treatment and biosensor development.


Assuntos
Enzimas Imobilizadas/química , Proteínas Fúngicas/química , Nanopartículas de Magnetita/química , Triazinas/química , Agaricus/enzimologia , Biocatálise , Estabilidade Enzimática , Química Verde , Concentração de Íons de Hidrogênio , Cinética , Levodopa/química , Oxirredução , Ligação Proteica
12.
Data Brief ; 9: 1098-1104, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27924296

RESUMO

Preparation and characterization of cross linked amine-functionalized magnetic nanoparticles as an appropriate support for covalent immobilization on tyrosinase was presented in the study "Covalent immobilization of tyrosinase onto cyanuric chloride crosslinked amine-functionalized superparamagnetic nanoparticles: synthesis and characterization of the recyclable nanobiocatalyst" (Abdollahi et al., 2016 ) [1]. Herein, complementary data regarding X-ray powder diffraction (XRD) to characterize the synthesized magnetic nanoparticles, and transmission electron microscopy (TEM) to determine the size and morphology of tyrosinase immobilized magnetic nanoparticles (tyrosinase-MNPs) were reported. The purification results of the extracted tyrosinase from mushroom Agaricus bisporus were provided in a purification table. The covalent immobilization of tyrosinase onto cyanuric chloride functionalized magnetic nanoparticles was proved by performing thermo-gravimetric and energy-dispersive X-ray spectroscopy analyses. The operational stability of immobilized tyrosinase was investigated by incubating tyrosinase-MNPs at different pH and temperatures.

13.
Appl Biochem Biotechnol ; 158(3): 736-46, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19015825

RESUMO

In the present study, biosorption of stable cobalt was studied in an up-flow fixed-bed column using the brown alga Sargassum glaucescens treated with formaldehyde (FA) or MgCl2. Notable increase in cobalt removal was observed for FA-treated biosorbent with 2.7 and 1.4 times higher dynamic capacity (DC) and uptake capacity (UC) than native alga, respectively. Consequently, FA-treated S. glaucescens was selected for further investigations. In particle size experiments, the DCs of 0.5-1 and 1-2 mm particles were both equal to 27.6 mg/g, and corresponding UCs were 34 and 38 mg/g, respectively. The maximum DC was obtained at residence time of 2.5 min. Studying the effect of additional ions indicated partial effect of Na+ and K+ ions on DC and UC, Mg2+ reduced highly the DC and slightly the UC while heavy metal ions (Ni2+, Cd2+, Cu2+, Zn2+, Pb2+ and Cr3+) caused decrease in both DC and UC about 1.5-4.7 and 1.8-3.2 times, respectively. Moreover, the column regeneration studies were carried out for four sorption-desorption cycles. The DC and the UC highly decreased in the second cycle, partially decreased or remained constant in the third and in the fourth one.


Assuntos
Cobalto/química , Sargassum/química , Purificação da Água/métodos , Adsorção , Biodegradação Ambiental , Biomassa , Reatores Biológicos , Cobalto/isolamento & purificação , Formaldeído/química , Sargassum/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...