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1.
PeerJ ; 12: e17328, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38770094

RESUMO

Nanotechnology and nanoparticles have gained massive attention in the scientific community in recent years due to their valuable properties. Among various AgNPs synthesis methods, microbial approaches offer distinct advantages in terms of cost-effectiveness, biocompatibility, and eco-friendliness. In the present research work, investigators have synthesized three different types of silver nanoparticles (AgNPs), namely AgNPs-K, AgNPs-M, and AgNPs-E, by using Klebsiella pneumoniae (MBC34), Micrococcus luteus (MBC23), and Enterobacter aerogenes (MBX6), respectively. The morphological, chemical, and elemental features of the synthesized AgNPs were analyzed by using UV-Vis spectroscopy (UV-Vis), Fourier transform-infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and energy-dispersive spectroscopy (EDX). UV-Vis absorbance peaks were obtained at 475, 428, and 503 nm for AgNPs-K, AgNPs-M, and AgNPs-E, respectively. The XRD analysis confirmed the crystalline nature of the synthesized AgNPs, having peaks at 26.2°, 32.1°, and 47.2°. At the same time, the FTIR showed bands at 599, 963, 1,693, 2,299, 2,891, and 3,780 cm-1 for all the types of AgNPs indicating the presence of bacterial biomolecules with the developed AgNPs. The size and morphology of the AgNPs varied from 10 nm to several microns and exhibited spherical to porous sheets-like structures. The percentage of Ag varied from 37.8% (wt.%) to 61.6%, i.e., highest in AgNPs-K and lowest in AgNPs-M. Furthermore, the synthesized AgNPs exhibited potential for environmental remediation, with AgNPs-M exhibiting the highest removal efficiency (19.24% at 120 min) for methyl orange dye in simulated wastewater. Further, all three types of AgNPs were evaluated for the removal of methyl orange dye from the simulated wastewater, where the highest dye removal percentage was 19.24% at 120 min by AgNPs-M. Antibacterial potential of the synthesized AgNPs assessment against both Gram-positive (GPB) Bacillus subtilis (MBC23), B. cereus (MBC24), and Gram-negative bacteria Enterococcus faecalis (MBP13) revealed promising results, with AgNPs-M, exhibiting the largest zone of inhibition (12 mm) against GPB B. megaterium. Such investigation exhibits the potential of the bacteria for the synthesis of AgNPs with diverse morphology and potential applications in environmental remediation and antibacterial therapy-based synthesis of AgNPs.


Assuntos
Compostos Azo , Nanopartículas Metálicas , Micrococcus luteus , Prata , Prata/química , Prata/farmacologia , Prata/metabolismo , Nanopartículas Metálicas/química , Compostos Azo/química , Compostos Azo/farmacologia , Compostos Azo/metabolismo , Micrococcus luteus/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/metabolismo , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/química , Enterobacter aerogenes/efeitos dos fármacos , Enterobacter aerogenes/metabolismo , Difração de Raios X , Poluentes Químicos da Água/metabolismo , Corantes/química , Corantes/farmacologia
4.
Sci Rep ; 14(1): 970, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38200095

RESUMO

The treatment of methylene blue (MB) dye wastewater through the adsorption process has been a subject of extensive research. However, a comprehensive understanding of the thermodynamic aspects of dye solution adsorption is lacking. Previous studies have primarily focused on enhancing the adsorption capacity of methylene blue dye. This study aimed to develop an environmentally friendly and cost-effective method for treating methylene blue dye wastewater and to gain insights into the thermodynamics and kinetics of the adsorption process for optimization. An adsorbent with selective methylene blue dye adsorption capabilities was synthesized using rice straw as the precursor. Experimental studies were conducted to investigate the adsorption isotherms and models under various process conditions, aiming to bridge gaps in previous research and enhance the understanding of adsorption mechanisms. Several adsorption isotherm models, including Langmuir, Temkin, Freundlich, and Langmuir-Freundlich, were applied to theoretically describe the adsorption mechanism. Equilibrium thermodynamic results demonstrated that the calculated equilibrium adsorption capacity (qe) aligned well with the experimentally obtained data. These findings of the study provide valuable insights into the thermodynamics and kinetics of methylene blue dye adsorption, with potential applications beyond this specific dye type. The utilization of rice straw as an adsorbent material presents a novel and cost-effective approach for MB dye removal from wastewater.

5.
Cureus ; 15(7): e41421, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37546146

RESUMO

Myeloid sarcoma, also known as granulocytic sarcoma or chloroma, is an extra-medullary accumulation of malignant myeloid blast cells, leading to a solid tumor formation. Herein, we report a rare presentation of a case with acute myeloid leukemia (AML), whose disease relapse was clinically evident as acute flaccid paraplegia with a certain sensory level. On thoracic spine magnetic resonance imaging (MRI), an epidural mass compressing the spinal cord at the level of the thoracic spine segment 4 (T4) was found. The mass histology confirmed the diagnosis of myeloid sarcoma.

6.
Environ Sci Pollut Res Int ; 30(28): 72641-72651, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37178290

RESUMO

Industrial effluents carrying dyes are considered a major environmental threat in the present era. Methylene blue (MB) dye is one of the key dyes of the thiazine group of dyes. It is broadly used in medical, textile, and various fields and is well known for its carcinogenicity and methemoglobin nature. Bacterial and other microbes-mediated bioremediation is becoming an emerging and significant section for the treatment of wastewater. Isolated bacteria were used for the bioremediation and nanobioremediation of methylene blue dye under varying conditions and parameters. A comparative study was conducted for the remediation of methylene blue dye using bacterial consortium, potential bacteria (isolated by scale-up method), and potential bacteria within zinc oxide nanoparticles. The decolorizing ability of bacteria was analyzed by UV visible spectrophotometer after stirring and static incubation in different time intervals of the isolates. Growth parameters and environmental parameters which include pH, initial dye concentration, and dose of nanoparticles were optimized with the minimal salt medium. An enzyme assay study was also done to check the effect of dye and nanoparticles on bacterial growth and the mode of action of degradation. The authors found that potential bacteria within ZnO nanoparticles showed enhanced decolorization efficiency (95.46% at pH 8) due to the properties of nanoparticles. On the other hand, the decolorization of MB dye by potential bacteria and the bacterial consortium was about 89.08 and 76.3%, respectively, for a 10-ppm dye concentration. During the enzyme assays study, the highest activity was observed for phenol oxidase, nicotinamide adenine dinucleotide (NADH), 2,6-Dichloroindophenol(DCIP), and laccase for nutrient broth having MB dye, MB dye, and ZnO NPs, while no such change was observed for manganese peroxidase enzyme activity. Nanobioremediation is a promising approach to removing such pollutants from the environment.


Assuntos
Nanopartículas , Óxido de Zinco , Águas Residuárias , Corantes/metabolismo , Óxido de Zinco/metabolismo , Azul de Metileno , Compostos Azo/metabolismo , Biodegradação Ambiental , Bactérias/metabolismo
7.
Molecules ; 28(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36615655

RESUMO

The unique biological and physicochemical characteristics of biogenic (green-synthesized) nanomaterials (NMs) have attracted significant interest in different fields, with applications in the agrochemical, food, medication delivery, cosmetics, cellular imaging, and biomedical industries. To synthesize biogenic nanomaterials, green synthesis techniques use microorganisms, plant extracts, or proteins as bio-capping and bio-reducing agents and their role as bio-nanofactories for material synthesis at the nanoscale size. Green chemistry is environmentally benign, biocompatible, nontoxic, and economically effective. By taking into account the findings from recent investigations, we shed light on the most recent developments in the green synthesis of nanomaterials using different types of microbes and plants. Additionally, we cover different applications of green-synthesized nanomaterials in the food and textile industries, water treatment, and biomedical applications. Furthermore, we discuss the future perspectives of the green synthesis of nanomaterials to advance their production and applications.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Química Verde/métodos , Plantas/química , Nanoestruturas/química , Alimentos , Extratos Vegetais/química , Nanopartículas Metálicas/química
8.
Front Microbiol ; 14: 1330071, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38239735

RESUMO

The primary goal of this experiment is to examine the effectiveness of Pseudomonas aeruginosa strain PAR as a rhizobacterium that promotes plant growth in mitigating the negative effects of fluoride-induced stress in tomato (Lycopersicon esculentum Mill.) plants. A total of 16 rhizobacterial strains were tested for plant growth-promoting (PGP) attributes, with isolates S1, S2, and S3 exhibiting different characteristics. Furthermore, growth kinetics studies revealed that these isolates were resilient to fluoride stress (10, 20, 40, and 80 ppm), with isolate S2 exhibiting notable resilience compared to the other two strains. Phylogenetic analysis revealed isolate S2 as P. aeruginosa strain PAR. Physiological analyses demonstrated that P. aeruginosa strain PAR had a beneficial impact on plant properties under fluoride stress, comprising seed germination, root length, shoot height, relative water content, and leaf area, the strain also impacted the buildup of glycine betaine, soluble sugar, and proline, demonstrating its significance in enhancing plant stress tolerance. In P. aeruginosa strain PAR-treated plants, chlorophyll content increased while malondialdehyde (MDA) levels decreased, indicating enhanced photosynthetic efficiency and less oxidative stress. The strain modified antioxidant enzyme action (catalase, ascorbate, glutathione reductase, peroxidase, and superoxide dismutase), which contributed to improved stress resilience. Mineral analysis revealed a decrease in sodium and fluoride concentrations while increasing magnesium, potassium, phosphorus, and iron levels, emphasizing the strain's significance in nutrient management. Correlation and principal component analysis revealed extensive correlations between physiological and biochemical parameters, underscoring P. aeruginosa strain PAR's multifaceted impact on plant growth and stress response. This study offers valuable information on effectively utilizing PGPR, particularly P. aeruginosa strain PAR, in fluoride-contaminated soils for sustainable agriculture. It presents a promising biological strategy to enhance crop resilience and productivity.

9.
Cureus ; 14(3): e23177, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35444918

RESUMO

Kikuchi-Fujimoto disease (KFD), also called histiocytic necrotizing lymphadenitis, is a benign self-limited disease involving lymph node enlargement with unclear causes and high fever. It was first seen in Japan and has wide array of differentials, and thus it can be confused with other causes of lymphadenitis leading to an incorrect treatment. We describe a case of a 34-year-old man with prolonged painless cervical lymphadenopathy and fever, in whom KFD, that is histiocytic necrotizing lymphadenitis, was diagnosed after the gold standard test of lymph node biopsy. Physical examination, history, and other relevant investigations were performed to rule out infectious and autoimmune causes. For management, prednisone 80mg and hydroxychloroquine were given, which lead to an uneventful full recovery. Our findings were compared to other similar studies conducted in the past. KFD is a self-limited condition that usually resolves by itself. KFD should be considered in the differential diagnosis of lymphadenopathy. An accurate diagnosis requires close collaboration between clinicians and pathologists. Early diagnosis of KFD allows reducing stress caused by alarming symptoms and avoiding unnecessary treatment.

10.
J Air Waste Manag Assoc ; 72(1): 76-84, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34618661

RESUMO

The effects of pH, particle size, adsorbent mass and stirring time on the adsorption efficiency were investigated. The univariate linear regression algorithm was applied on experimental data to rank the most effective parameters on the Ni(II) removal percentage. Response surface method (RSM) was then applied to model and optimize the operating conditions of the removal process. Results revealed that the most effective operation parameters on Ni(II) removal is the solution's pH. It has been concluded that the highest removal of 94.13% is obtained with stirring time of 29.15 min, particle size 137.81 µm, added mass absorbent of 0.346 g and pH of 12.04. Experimental verification showed removal percentage of 93.5% concluding agreement with that obtained by model prediction.Implications: The removal of Ni(II) ions from wastewater utilizing the agricultural waste of date seed powder is dominated by many parameters; solution pH, initial Ni(II) concentration, adsorbent mass, particle size, operational temperature and contact time. This research classifies these parameters to define the ones that significantly impacts the removal process. Modeling of these parameters was then conducted to study the impact of every set on the removal efficiency thus defining the optimum operating conditions. The findings of this study can be used to create optimal operating conditions that are capable of achieving higher removal percentages than are currently available.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Pós , Águas Residuárias
11.
Polymers (Basel) ; 13(21)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34771248

RESUMO

Heavy metals are toxic substances that pose a real danger to humans and organisms, even at low concentration. Therefore, there is an urgent need to remove heavy metals. Herein, the nanocellulose (NC) was synthesized by the hydrolysis of cellulose using sulfuric acid, and then functionalized using polypyrrole (ppy) through a polymerization reaction to produce polypyrrole/nanocellulose (ppy/NC) nanocomposite. The synthesized nanocomposite was characterized using familiar techniques including XRD, FT-IR, SEM, TEM, and TGA. The obtained results showed a well-constructed nanocomposite with excellent thermal stability in the nano-sized scale. The adsorption experiments showed that the ppy/NC nanocomposite was able to adsorb hexavalent chromium (Cr(VI)). The optimum pH for the removal of the heavy metal was pH 2. The interfering ions showed minor effect on the adsorption of Cr(VI) resulted from the competition between ions for the adsorption sites. The adsorption kinetics were studied using pseudo 1st order and pseudo 2nd order models indicating that the pseudo second order model showed the best fit to the experimental data, signifying that the adsorption process is controlled by the chemisorption mechanism. Additionally, the nanocomposite showed a maximum adsorption capacity of 560 mg/g according to Langmuir isotherm. The study of the removal mechanism showed that Cr(VI) ions were removed via the reduction of high toxic Cr(VI) to lower toxic Cr(III) and the electrostatic attraction between protonated ppy and Cr(VI). Interestingly, the ppy/NC nanocomposite was reused for Cr(VI) uptake up to six cycles showing excellent regeneration results. Subsequently, Cr(VI) ions can be effectively removed from aqueous solution using the synthesized nanocomposite as reusable and cost-effective adsorbent.

12.
Saudi J Biol Sci ; 28(7): 4010-4015, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33867805

RESUMO

By the beginning of 2021, the battle against coronavirus disease 2019 (COVID-19) remains ongoing. Investigating the adaptive immune response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes COVID-19, in patients who have recovered from this disease could contribute to our understanding of the natural host immune response. We enrolled 38 participants in this study. 7 healthy participants and 31 COVID-19 patients who had recovered from COVID-19 and categorized them into 3 groups according to their previous clinical presentations: 10 moderate, 9 mild, and 12 asymptomatic. Flow cytometry analysis of peripheral lymphocyte counts in recovered patients showed significantly increased levels of CD4+ T cells in patients with a history of mild and moderate COVID-19 symptoms compared with those healthy individuals (p < 0.05 and p < 0.0001 respectively). whereas no significant difference was observed in the CD8+ T cell percentage in COVID-19-recovered patients compared with healthy individuals. Our study demonstrated that antibodies against the SARS-CoV-2 spike protein (anti-S) IgG antibody production could be observed in all recovered COVID-19 patients, regardless of whether they were asymptomatic (p < 0.05)or presented with mild (p < 0.0001) or moderate symptoms (p < 0.01). Anti-S IgG antibodies could be detected in participants up to 90 days post-infection. In conclusion, the lymphocyte levels in recovered patients were associated with the clinical presentation of the disease, and further analysis is required to investigate relationships between different clinical presentations and lymphocyte activation and function.

13.
Cureus ; 13(1): e13033, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33665054

RESUMO

Multiple autoimmune syndrome (MAS) is a condition characterized by three or more autoimmune disorders in the same individual. The development of MAS involves genetic, immunological, and infectious factors. Here we report a case of a 40-year-old man who presented with four autoimmune diseases, namely autoimmune hypothyroidism, alopecia universalis, celiac disease, and immune thrombocytopenic purpura (ITP), which leads to a diagnosis of MAS. However, the patient does not fit in any category of MAS classification. In addition to the need for continued surveillance for the development of new autoimmune disease in predisposed patients, this case report suggests an additional fourth category of the classification of MAS that includes autoimmune hypothyroidism, alopecia universalis, celiac disease, and ITP.

14.
Cureus ; 13(1): e12600, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-33585090

RESUMO

Vitamin B12 has essential roles in DNA synthesis, red blood cell development, and neurologic functions. Vitamin B12 deficiency is relatively common, particularly in people aged over 60 years. Among hematological disturbances, microangiopathic hemolytic anemia with thrombocytopenia or so-called pseudo-thrombotic microangiopathy (pseudo-TMA) is a particularly rare but significant clinical complication in patients with vitamin B12 deficiency. We herein describe a case of an elderly patient with pseudo-TMA whose lack of vitamin B12 was misdiagnosed as thrombotic thrombocytopenic purpura (TTP). The patient was admitted as a case of pancytopenia with a hemolytic picture. The initial impression was TTP versus acute promyelocytic leukemia M3. After examination of laboratory tests and bone marrow examination, we deduced that the patient had a B12 deficiency. The condition of the patient improved with B12 replacement. This report should remind physicians to widen their differential diagnoses when patients present with microangiopathic hemolysis or in patients who are not responsive to standard treatments for TTP.

15.
Foods ; 8(4)2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31027260

RESUMO

This paper compares four different modeling techniques: Response Surface Method (RSM), Linear Radial Basis Functions (LRBF), Quadratic Radial Basis Functions (QRBF), and Artificial Neural Network (ANN). The models were tested by monitoring their performance in predicting the optimum operating conditions for Sesame seed oil extraction yields. Experimental data using three different solvents-hexane, chloroform, and acetone-with varying ratios of solvents to seeds, all under different temperatures, rotational speeds, and mixing times, were modeled by the three proposed techniques. Efficiency for model predictions was examined by monitoring error value performance indicators (R2, R2adj, and RMSE). Results showed that the applied modeling techniques gave good agreements with experimental data regardless of the efficiency of the solvents in oil extraction. On the other hand, the ANN model consistently performed more accurate predictions with all tested solvents under all different operating conditions. This consistency is demonstrated by the higher values of R2 and R2adj ratio equals to one and the very low value of error of RMSE (2.23 × 10-3 to 3.70 × 10-7), thus concluding that ANN possesses a universal ability to approximate nonlinear systems in comparison to other models.

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