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1.
Environ Res ; 260: 119618, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39009211

RESUMO

Lignites are widely available and cost-effective in many countries. Sustainable methods for their utilization drive innovation, potentially advancing environmental sustainability and resource efficiency. In the present study, Fe3O4 (∼25.1 nm) supported on KOH-activated lignite (A-L) displayed 8 times higher phosphate removal than pristine A-L (67.6 mg/g vs. 8.5 mg/g at pH 5, 50 mg of absorbent in 25 mL of 1500 ppm [phosphate]), owing to its abundant Fe3O4 (10 wt% of Fe) nanoparticle content. The removal occurred within ∼2 h, following a pseudo-second-order kinetic model. Across pH levels ranging from 5.0 to 9.0, Fe3O4-A-L's phosphate removal occurs via both chemisorption and precipitation, as evident by kinetic, pH, and XPS analyses. The phosphate adsorption fits better with the Freundlich isotherm. The combined benefits of facile recovery, rapid phosphate uptake, straightforward regeneration, and attractive post-adsorption benefits (e.g., possibly use as a Fe, P-rich fertilizer) make magnetic Fe3O4-A-L a promising candidate for real-world applications. Artificial Neural Network (ANN) modeling indicates an excellent accuracy (R2 = 0.99) in predicting the amount of phosphate removed by Fe3O4-A-L. Sensitivity analysis revealed both temperature and initial concentration as the most influencing factors. Leveraging lignite in environmentally friendly applications not only addresses immediate challenges but also aligns with sustainability goals. The study clearly articulates the potential benefits of utilizing lignite for sustainable phosphate removal and recovery, offering avenues for mitigating environmental concerns while utilizing resources efficiently.


Assuntos
Redes Neurais de Computação , Fosfatos , Poluentes Químicos da Água , Fosfatos/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Adsorção , Carvão Mineral , Compostos Férricos/química , Cinética , Concentração de Íons de Hidrogênio , Purificação da Água/métodos
2.
J Family Med Prim Care ; 12(10): 2507-2509, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38074223

RESUMO

We report a very rare case of 35-year-old female with a giant mandibular osteoma in the angle of the mandible. We highlight the importance of CT in diagnosing as well as defining the extent of this rare case so that proper management can be undertaken. We also showcase the importance of angiography to show relationship of this mass with the surrounding vessels.

3.
Int J Mol Sci ; 24(5)2023 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36902011

RESUMO

Astrocytes are critical players in brain health and disease. Sphingosine-1-phosphate (S1P), a bioactive signaling lipid, is involved in several vital processes, including cellular proliferation, survival, and migration. It was shown to be crucial for brain development. Its absence is embryonically lethal, affecting, inter alia, the anterior neural tube closure. However, an excess of S1P due to mutations in S1P-lyase (SGPL1), the enzyme responsible for its constitutive removal, is also harmful. Of note, the gene SGPL1 maps to a region prone to mutations in several human cancers and also in S1P-lyase insufficiency syndrome (SPLIS) characterized by several symptoms, including peripheral and central neurological defects. Here, we investigated the impact of S1P on astrocytes in a mouse model with the neural-targeted ablation of SGPL1. We found that SGPL1 deficiency, and hence the accumulation of its substrate, S1P, causes the elevated expression of glycolytic enzymes and preferentially directs pyruvate into the tricarboxylic acid (TCA) cycle through its receptors (S1PR2,4). In addition, the activity of TCA regulatory enzymes was increased, and consequently, so was the cellular ATP content. The high energy load activates the mammalian target of rapamycin (mTOR), thus keeping astrocytic autophagy in check. Possible consequences for the viability of neurons are discussed.


Assuntos
Astrócitos , Esfingosina , Camundongos , Animais , Humanos , Astrócitos/metabolismo , Esfingosina/metabolismo , Encéfalo/metabolismo , Lisofosfolipídeos/metabolismo , Aldeído Liases/genética , Autofagia/fisiologia , Trifosfato de Adenosina/metabolismo , Mamíferos/metabolismo
4.
Mol Oncol ; 16(20): 3642-3653, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35973936

RESUMO

Sphingosine-1-phosphate (S1P), a bioactive signaling lipid, is involved in several vital processes, including cellular proliferation, survival and migration, as well as neovascularization and inflammation. Its critical role in the development and progression of cancer is well documented. The metabolism of S1P, which exerts its effect mainly via five G protein-coupled receptors (S1PR1-5 ), is tightly regulated. S1P-lyase (SGPL1) irreversibly cleaves S1P in the final step of sphingolipid catabolism and exhibits remarkably decreased enzymatic activity in tumor samples. In this study, we used SGPL1-deficient (Sgpl1-/- ) mouse embryonic fibroblasts (MEFs) and investigated the impact of S1P on glucose metabolism. Accumulated S1P activates, via its receptors (S1PR1-3 ), hypoxia-inducible factor 1 and stimulates the expression of proteins involved in glucose uptake and breakdown, indicating that Sgpl1-/- cells, like cancer cells, prefer to convert glucose to lactate even in the presence of oxygen. Accordingly, their rate of proliferation is significantly increased. Activation of the Akt/mTOR pathway and hence down-regulation of autophagy indicate that these changes do not negatively affect the cellular energy status. In summary, we report on a newly identified role of the S1P/S1PR1-3 axis in glucose metabolism in SGPL1-deficient MEFs.


Assuntos
Aldeído Liases , Fibroblastos , Proteínas Proto-Oncogênicas c-akt , Animais , Camundongos , Carcinogênese/metabolismo , Transformação Celular Neoplásica/metabolismo , Fibroblastos/metabolismo , Glucose/metabolismo , Fator 1 Induzível por Hipóxia/metabolismo , Lactatos/metabolismo , Lisofosfolipídeos/metabolismo , Oxigênio , Proteínas Proto-Oncogênicas c-akt/metabolismo , Esfingolipídeos/metabolismo , Esfingosina/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Aldeído Liases/genética , Camundongos Knockout
5.
Ann Med Surg (Lond) ; 74: 103249, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35039779

RESUMO

Vasculitis is one of the complications of COVID-19. We conducted a systematic review analysing the association of COVID-19 with vasculitis. We searched Google Scholar and PubMed from December 1, 2019, to October 11, 2021. The review included 8 studies (7 case reports and 1 case series) reporting 9 cases of vasculitis secondary to COVID-19. The mean age was 29.17 ± 28.2 years, ranging from 6 months to 83 years. The male to female ratio was 4:5. Maculopapular, violaceous, papular and erythematous rash were common. Heparin(n = 2), corticosteroids (n = 6) (methylprednisolone) and intravenous immunoglobulin (n = 4) were prescribed in these patients. Significant clinical improvement was observed in 8 out of 9 patients. One person died during treatment. Our study discusses vasculitis as one of the complications of COVID-19. Furthermore, the pathophysiology, clinical presentation, and management of COVID-19 associated vasculitis is discussed.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32283310

RESUMO

Sphingosine-1-phosphate (S1P) is not only a catabolic intermediate of all sphingolipids but also an evolutionary conserved bioactive lipid with critical functions in cell survival, differentiation, and migration as well as in immunity and angiogenesis. S1P-lyase (SGPL1) irreversibly cleaves S1P in the final step of sphingolipid catabolism. As sphingoid bases and their 1-phosphates are not only metabolic intermediates but also highly bioactive lipids that modulate a wide range of physiological processes, it would be predicted that their elevation might induce adjustments in other facets of sphingolipid metabolism and/or alter cell behavior. We actually found in a previous study that in terminally differentiated neurons SGPL1 deficiency increases sphingolipid formation via recycling at the expense of de novo synthesis. We now investigated whether and how SGPL1 deficiency affects the metabolism of (glyco)sphingolipids in mouse embryonic fibroblasts (MEFs). According to our previous experiments in neurons, we found a strong accumulation of S1P in SGPL1-deficient MEFs. Surprisingly, a completely different situation arose as we analyzed sphingolipid metabolism in this non-differentiated cell type. The production of biosynthetic precursors of complex glycosphingolipids including ceramide, glucosylceramide and also ganglioside GM3 via de novo synthesis and recycling pathway was substantially increased whereas the amount of more complex gangliosides dropped significantly.


Assuntos
Aldeído Liases/deficiência , Aldeído Liases/metabolismo , Carcinogênese , Gangliosídeos/biossíntese , Animais , Células Cultivadas , Gangliosídeos/análise , Camundongos , Camundongos Knockout
7.
Glia ; 67(10): 1859-1872, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31231866

RESUMO

Microglia mediated responses to neuronal damage in the form of neuroinflammation is a common thread propagating neuropathology. In this study, we investigated the microglial alterations occurring as a result of sphingosine 1-phosphate (S1P) accumulation in neural cells. We evidenced increased microglial activation in the brains of neural S1P-lyase (SGPL1) ablated mice (SGPL1fl/fl/Nes ) as shown by an activated and deramified morphology and increased activation markers on microglia. In addition, an increase of pro-inflammatory cytokines in sorted and primary cultured microglia generated from SGPL1 deficient mice was noticed. Further, we assessed autophagy, one of the major mechanisms in the brain that keeps inflammation in check. Indeed, microglial inflammation was accompanied by defective microglial autophagy in SGPL1 ablated mice. Rescuing autophagy by treatment with rapamycin was sufficient to decrease interleukin 6 (IL-6) but not tumor necrosis factor (TNF) secretion in cultured microglia. Rapamycin mediated decrease of IL-6 secretion suggests a particular mechanistic target of rapamycin (mTOR)-IL-6 link and appeared to be microglia specific. Using pharmacological inhibitors of the major receptors of S1P expressed in the microglia, we identified S1P receptor 2 (S1PR2) as the mediator of both impaired autophagy and proinflammatory effects. In line with these results, the addition of exogenous S1P to BV2 microglial cells showed similar effects as those observed in the genetic knock out of SGPL1 in the neural cells. In summary, we show a novel role of the S1P-S1PR2 axis in the microglia of mice with neural-targeted SGPL1 ablation and in BV2 microglial cell line exogenously treated with S1P.


Assuntos
Aldeído Liases/metabolismo , Autofagia/fisiologia , Inflamação/metabolismo , Microglia/metabolismo , Aldeído Liases/antagonistas & inibidores , Aldeído Liases/genética , Animais , Células Cultivadas , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Inflamação/patologia , Interleucina-6/metabolismo , Camundongos Transgênicos , Microglia/patologia , Receptores de Esfingosina-1-Fosfato/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
8.
Drug Discov Ther ; 12(6): 374-378, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30674773

RESUMO

Mucormycosis is an uncommon aggressive fungal infection usually seen in immunocompromised hosts or patients with burns and trauma. The common presentations include rhino-orbital-cerebral and pulmonary involvement. Osteoarticular involvement is a rare presentation of this disease. We present two cases of osteoarticular mucormycosis of pelvis and long bones of the lower limb, one in a patient with burn injury and other one in a patient with chronic granulomatous disease, hitherto a rarely reported association. Delayed diagnosis in a setting where tuberculosis is a common cause of chronic osteomyelitis, challenges in medical and surgical management of these patients are discussed in this report.


Assuntos
Doença Granulomatosa Crônica/microbiologia , Extremidade Inferior/microbiologia , Mucormicose/diagnóstico , Mucormicose/terapia , Ossos Pélvicos/microbiologia , Adulto , Amputação Cirúrgica , Antifúngicos/uso terapêutico , Queimaduras/microbiologia , Queimaduras/cirurgia , Desbridamento/efeitos adversos , Gerenciamento Clínico , Humanos , Extremidade Inferior/cirurgia , Masculino , Mucormicose/etiologia , Ossos Pélvicos/cirurgia , Adulto Jovem
9.
Pak J Biol Sci ; 10(1): 117-21, 2007 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19069996

RESUMO

The extra-cellular export of the HR-eliciting protein, Harpin(Es) of the maize pathogen Erwinia stewartii was studied to find out if the protein needs any species-specific signal for its export and to determine if the export of the protein to the medium is affected in any way by the growth temperature. Based upon the experimental evidence, it was proved that the protein (i.e., Harpin(Es)) does require its own export system (species-specific) to get out of the bacterial cell and can not be exported by the export system of even the very closely related bacterium, Erwinia amylovora. It was also found that the export of Harpin(Es) is, unlike the case of Harpin(Ea) (HR-eliciting protein of Erwinia amylovora), independent of the growth temperature.


Assuntos
Proteínas da Membrana Bacteriana Externa/metabolismo , Erwinia/metabolismo , Temperatura , Zea mays/crescimento & desenvolvimento , Zea mays/microbiologia , Proteínas da Membrana Bacteriana Externa/genética , Erwinia/genética , Erwinia/patogenicidade , Praguicidas/metabolismo , Especificidade da Espécie , Nicotiana/metabolismo , Nicotiana/microbiologia , Zea mays/genética
10.
Skeletal Radiol ; 36 Suppl 1: S101-4, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16988800

RESUMO

Osteomyelitis may pose as a diagnostic dilemma on various imaging modalities and may be confused with neoplasms and other pathology. Although a rare finding, extra-osseous fat fluid level, especially when associated with spongy bone destruction, can be considered a specific sign of osteomyelitis. Previously, only two cases of extra-osseous fat fluid level in osteomyelitis have been reported, one on computed tomography (CT) and the other on magnetic resonance imaging (MRI). The former was a case of septic arthritis with intra-articular fat fluid level. A case of osteomyelitis is presented with the demonstration of extra-osseous fat fluid level. Our case is unique in providing exquisite CT and MRI correlation.


Assuntos
Tecido Adiposo/patologia , Osteomielite/diagnóstico , Adolescente , Biópsia , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Osteomielite/diagnóstico por imagem , Osteomielite/patologia , Tomografia Computadorizada por Raios X
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