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1.
Immunity ; 49(6): 1077-1089.e5, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30552020

RESUMO

Inflammatory bowel disease (IBD) results from a dysregulated interaction between the microbiota and a genetically susceptible host. Genetic studies have linked TNFSF15 polymorphisms and its protein TNF-like ligand 1A (TL1A) with IBD, but the functional role of TL1A is not known. Here, we found that adherent IBD-associated microbiota induced TL1A release from CX3CR1+ mononuclear phagocytes (MNPs). Using cell-specific genetic deletion models, we identified an essential role for CX3CR1+MNP-derived TL1A in driving group 3 innate lymphoid cell (ILC3) production of interleukin-22 and mucosal healing during acute colitis. In contrast to this protective role in acute colitis, TL1A-dependent expression of co-stimulatory molecule OX40L in MHCII+ ILC3s during colitis led to co-stimulation of antigen-specific T cells that was required for chronic T cell colitis. These results identify a role for ILC3s in activating intestinal T cells and reveal a central role for TL1A in promoting ILC3 barrier immunity during colitis.


Assuntos
Colite/imunologia , Imunidade Inata/imunologia , Linfócitos/imunologia , Microbiota/imunologia , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/imunologia , Adulto , Idoso , Animais , Colite/genética , Colite/metabolismo , Feminino , Humanos , Imunidade Inata/genética , Interleucinas/genética , Interleucinas/imunologia , Interleucinas/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Linfócitos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Microbiota/fisiologia , Pessoa de Meia-Idade , Fagócitos/citologia , Fagócitos/imunologia , Fagócitos/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Adulto Jovem , Interleucina 22
2.
Proc Natl Acad Sci U S A ; 120(34): e2120771120, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37579137

RESUMO

The binding of tumor necrosis factor-like cytokine 1A (TL1A) to death receptor 3 (DR3) plays an important role in the interaction between dendritic cells (DCs) and T cells and contributes to intestinal inflammation development. However, the mechanism by which DCs expressing TL1A mediate helper T (Th) cell differentiation in the intestinal lamina propria (LP) during the pathogenesis of inflammatory bowel disease remains unclear. In this study, we found that TL1A/DR3 promoted Th1 and Th17 cell differentiation in T-T and DC-T cell interaction-dependent manners. TL1A-deficient CD4+ T cells failed to polarize into Th1/Th17 cells and did not cause colonic inflammation in a T cell transfer colitis model. Notably, TL1A was located in the cytoplasm and nuclei of DCs, positively regulated the DC-specific ICAM-grabbing nonintegrin/RAF1/nuclear factor κB signaling pathway, enhanced the antigen uptake ability of DCs, and promoted TLR4-mediated DC activation, inducing naive CD4+ T cell differentiation into Th1 and Th17 cells. Our work reveals that TL1A plays a regulatory role in inflammatory bowel disease pathogenesis.


Assuntos
Doenças Inflamatórias Intestinais , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral , Humanos , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Membro 25 de Receptores de Fatores de Necrose Tumoral/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Inflamação/metabolismo , Fator de Necrose Tumoral alfa
3.
Biochem Biophys Res Commun ; 697: 149544, 2024 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-38245927

RESUMO

T-cell immunoglobulin and mucin protein 3 (Tim-3), also known as Hepatitis A virus cellular receptor 2, has been discovered to have a negative regulatory effect on murine T-cell responses. Galectin-9 exhibits various biological effects, including cell aggregation, eosinophil chemoattraction, activation, and apoptosis, observed in murine thymocytes, T-cells, and human melanoma cells. Such approach demonstrated that Galectin-9 acts as a binding partner on Tim-3 and mediates the T-cell inhibitory effects. Tl-gal is a homologous protein to galectin-9, isolated from the adult stage of the canine gastrointestinal nematode parasite Toxascaris leonina. However, molecular mechanism between Tim-3 and galectin-9 is still remain unknown. Here, we describe the cryo-electron microscopy and X-ray structures and interactions of the Tim-3 and Tl-gal complex as well as their biochemical and biophysical characterization. In the structure, Ser46 residue of Tl-gal NCRD was bound to Asp25 residue of hTim-3. Compared to our previous study, the binding site of the complex is the same as the sugar binding site (the Ser46 residue) of Tl-gal. In addition, analysis of the complex structure revealed that the four Tl-gal molecules were in an open form packing and one mTim-3 peptide was bound to one Tl-gal molecule. These observations suggest that how Tl-gal binds hTim3 is essential to understanding the molecular mechanism for the Tim-3-galectin 9 interaction that regulates immune responses. This could potentially serve as a therapeutic target for inflammatory diseases.


Assuntos
Receptor Celular 2 do Vírus da Hepatite A , Toxascaris , Adulto , Camundongos , Animais , Humanos , Cães , Toxascaris/química , Toxascaris/metabolismo , Microscopia Crioeletrônica , Galectinas/metabolismo , Imunoglobulinas , Mucinas
4.
J Transl Med ; 22(1): 503, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802941

RESUMO

BACKGROUND: Prion diseases are transmissible and fatal neurodegenerative diseases characterized by accumulation of misfolded prion protein isoform (PrPSc), astrocytosis, microgliosis, spongiosis, and neurodegeneration. Elevated levels of cell membrane associated PrPSc protein and inflammatory cytokines hint towards the activation of death receptor (DR) pathway/s in prion diseases. Activation of DRs regulate, either cell survival or apoptosis, autophagy and necroptosis based on the adaptors they interact. Very little is known about the DR pathways activation in prion disease. DR3 and DR5 that are expressed in normal mouse brain were never studied in prion disease, so also their ligands and any DR adaptors. This research gap is notable and investigated in the present study. METHODS: C57BL/6J mice were infected with Rocky Mountain Laboratory scrapie mouse prion strain. The progression of prion disease was examined by observing morphological and behavioural abnormalities. The levels of PrP isoforms and GFAP were measured as the marker of PrPSc accumulation and astrocytosis respectively using antibody-based techniques that detect proteins on blot and brain section. The levels of DRs, their glycosylation and ectodomain shedding, and associated factors warrant their examination at protein level, hence western blot analysis was employed in this study. RESULTS: Prion-infected mice developed motor deficits and neuropathology like PrPSc accumulation and astrocytosis similar to other prion diseases. Results from this research show higher expression of all DR ligands, TNFR1, Fas and p75NTR but decreased levels DR3 and DR5. The levels of DR adaptor proteins like TRADD and TRAF2 (primarily regulate pro-survival pathways) are reduced. FADD, which primarily regulate cell death, its level remains unchanged. RIPK1, which regulate pro-survival, apoptosis and necroptosis, its expression and proteolysis (inhibits necroptosis but activates apoptosis) are increased. CONCLUSIONS: The findings from the present study provide evidence towards the involvement of DR3, DR5, DR6, TL1A, TRAIL, TRADD, TRAF2, FADD and RIPK1 for the first time in prion diseases. The knowledge obtained from this research discuss the possible impacts of these 16 differentially expressed DR factors on our understanding towards the multifaceted neuropathology of prion diseases and towards future explorations into potential targeted therapeutic interventions for prion disease specific neuropathology.


Assuntos
Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Doenças Priônicas , Animais , Doenças Priônicas/metabolismo , Doenças Priônicas/patologia , Receptores de Morte Celular/metabolismo , Transdução de Sinais , Encéfalo/metabolismo , Encéfalo/patologia , Camundongos , Proteínas PrPSc/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo
5.
Cytokine ; 176: 156540, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38359559

RESUMO

Death Receptor 3 (DR3) is a cytokine receptor of the Tumor Necrosis Factor receptor superfamily that plays a multifaceted role in both innate and adaptive immunity. Based on the death domain motif in its cytosolic tail, DR3 had been proposed and functionally affirmed as a trigger of apoptosis. Further studies, however, also revealed roles of DR3 in other cellular pathways, including inflammation, survival, and proliferation. DR3 is expressed in various cell types, including T cells, B cells, innate lymphocytes, myeloid cells, fibroblasts, and even outside the immune system. Because DR3 is mainly expressed on T cells, DR3-mediated immune perturbations leading to autoimmunity and other diseases were mostly attributed to DR3 activation of T cells. However, which T cell subset and what T effector functions are controlled by DR3 to drive these processes remain incompletely understood. DR3 engagement was previously found to alter CD4 T helper subset differentiation, expand the Foxp3+ Treg cell pool, and maintain intraepithelial γδ T cells in the gut. Recent studies further unveiled a previously unacknowledged aspect of DR3 in regulating innate-like invariant NKT (iNKT) cell activation, expanding the scope of DR3-mediated immunity in T lineage cells. Importantly, in the context of iNKT cells, DR3 ligation exerted costimulatory effects in agonistic TCR signaling, unveiling a new regulatory framework in T cell activation and proliferation. The current review is aimed at summarizing such recent findings on the role of DR3 on conventional T cells and innate-like T cells and discussing them in the context of immunopathogenesis.


Assuntos
Receptores de Citocinas , Membro 25 de Receptores de Fatores de Necrose Tumoral , Humanos , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral , Inflamação/metabolismo , Subpopulações de Linfócitos T/metabolismo
6.
Respir Res ; 25(1): 271, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987753

RESUMO

BACKGROUND: Airway epithelial cell (AEC) necroptosis contributes to airway allergic inflammation and asthma exacerbation. Targeting the tumor necrosis factor-like ligand 1 A (TL1A)/death receptor 3 (DR3) axis has a therapeutic effect on asthmatic airway inflammation. The role of TL1A in mediating necroptosis of AECs challenged with ovalbumin (OVA) and its contribution to airway inflammation remains unclear. METHODS: We evaluated the expression of the receptor-interacting serine/threonine-protein kinase 3(RIPK3) and the mixed lineage kinase domain-like protein (MLKL) in human serum and lung, and histologically verified the level of MLKL phosphorylation in lung tissue from asthmatics and OVA-induced mice. Next, using MLKL knockout mice and the RIPK3 inhibitor GSK872, we investigated the effects of TL1A on airway inflammation and airway barrier function through the activation of necroptosis in experimental asthma. RESULTS: High expression of necroptosis marker proteins was observed in the serum of asthmatics, and necroptosis was activated in the airway epithelium of both asthmatics and OVA-induced mice. Blocking necroptosis through MLKL knockout or RIPK3 inhibition effectively attenuated parabronchial inflammation, mucus hypersecretion, and airway collagen fiber accumulation, while also suppressing type 2 inflammatory factors secretion. In addition, TL1A/ DR3 was shown to act as a death trigger for necroptosis in the absence of caspases by silencing or overexpressing TL1A in HBE cells. Furthermore, the recombinant TL1A protein was found to induce necroptosis in vivo, and knockout of MLKL partially reversed the pathological changes induced by TL1A. The necroptosis induced by TL1A disrupted the airway barrier function by decreasing the expression of tight junction proteins zonula occludens-1 (ZO-1) and occludin, possibly through the activation of the NF-κB signaling pathway. CONCLUSIONS: TL1A-induced airway epithelial necroptosis plays a significant role in promoting airway inflammation and barrier dysfunction in asthma. Inhibition of the TL1A-induced necroptosis pathway could be a promising therapeutic strategy.


Assuntos
Asma , Camundongos Knockout , Necroptose , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral , Animais , Asma/metabolismo , Asma/patologia , Necroptose/fisiologia , Humanos , Camundongos , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Masculino , Feminino , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Camundongos Endogâmicos C57BL , Proteínas Quinases/metabolismo , Inflamação/metabolismo , Inflamação/patologia , Ovalbumina/toxicidade
7.
Exp Eye Res ; 243: 109908, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38657787

RESUMO

Zebrafish are an outstanding model for assessing the involvement of genes in paediatric cataracts. Gene discovery for cataracts is enhanced by manipulation of the genome of zebrafish embryos and comparing the phenotypes of mutant progeny with the wildtype embryos. However, wildtype laboratory fish can also develop cataracts, potentially confounding the results. In this study, we compared the baseline cataract rate between two commonly used wildtype laboratory strains, AB and TL, and also an outbred transgenic line with mCherry reporter. We assessed a total of 805 lens images of fish at 4 days post-fertilisation for cataracts and scored each cataract observed as mild, moderate or severe. We found that the AB strain had a cataract rate of 16.2%, TL had 8.9%, and mCherry had 0.7% and these rates were significantly different. We found that TL strain had a lower rate of mild cataracts than AB fish, however, the rate of moderate and severe phenotypes in the AB and the TL strain was similar. Overall, we showed that the baseline cataract rate varies significantly between the strains housed in a single facility and conclude that baseline rates of cataracts should be assessed when planning experiments to assess the genetic causes of cataracts.


Assuntos
Animais Geneticamente Modificados , Catarata , Modelos Animais de Doenças , Cristalino , Fenótipo , Peixe-Zebra , Animais , Peixe-Zebra/genética , Catarata/genética , Cristalino/patologia
8.
Am J Med Genet A ; 194(3): e63461, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37953071

RESUMO

The MT-TL2 m.12315G>A pathogenic variant has previously been reported in five individuals with mild clinical phenotypes. Herein we report the case of a 5-year-old child with heteroplasmy for this variant who developed neurological regression and stroke-like episodes similar to those observed in mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS). Biochemical evaluation revealed depletion of arginine on plasma amino acid analysis and low z-scores for citrulline on untargeted plasma metabolomics analysis. These findings suggested that decreased availability of nitric oxide may have contributed to the stroke-like episodes. The use of intravenous arginine during stroke-like episodes and daily enteral L-citrulline supplementation normalized her biochemical values of arginine and citrulline. Untargeted plasma metabolomics showed the absence of nicotinamide and 1-methylnicotinamide, and plasma total glutathione levels were low; thus, nicotinamide riboside and N-acetylcysteine therapies were initiated. This report expands the phenotype associated with the rare mitochondrial variant MT-TL2 m.12315G>A to include neurological regression and a MELAS-like phenotype. Individuals with this variant should undergo in-depth biochemical analysis to include untargeted plasma metabolomics, plasma amino acids, and glutathione levels to help guide a targeted approach to treatment.


Assuntos
Acidose Láctica , Síndrome MELAS , Encefalomiopatias Mitocondriais , Acidente Vascular Cerebral , Pré-Escolar , Feminino , Humanos , Arginina/genética , Citrulina , Glutationa/metabolismo , Síndrome MELAS/diagnóstico , Síndrome MELAS/genética , Síndrome MELAS/complicações , Doadores de Óxido Nítrico/metabolismo , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico
9.
Luminescence ; 39(3): e4723, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38516725

RESUMO

The investigation of thermoluminescence (TL) glow curves in liquid crystalline side chain N-phenyl-substituted phenyl polysiloxane hydroxamic acids (PHAs) has yielded significant insights. These polymers demonstrated TL behavior when exposed to ß-radiation between 0 and 220°C, indicating inherent luminescent properties when irradiated. Notably, a dose-dependent relationship was observed in reported derivatized polymers; this study elucidates the diverse TL characteristics exhibited by various liquid crystalline side chain N-phenyl-substituted phenyl PHAs when exposed to ß-radiation. Understanding these dose-dependent and dose-independent behaviors enhances the knowledge of their luminescent properties and potential applications in radiation detection.


Assuntos
Luminescência , Siloxanas , Dosimetria Termoluminescente
10.
Luminescence ; 39(5): e4755, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38689564

RESUMO

The ultimate goal of this work is the study of the effect of luminescence stimulations and signals reading modes combinations on the thermoluminescence intensity and glow curve behaviour for the same X-ray irradiation dose. Three interesting stimulating and reading modes are considered, namely, infrared stimulated luminescence (IRSL), blue light-emitting diode stimulated luminescence (BLSL) and thermally stimulated luminescence (TSL). The studied stimulation and reading modes combination protocols are (Protocol 1) IRSL-TSL, (Protocol 2) IRSL-BLSL-TSL and (Protocol 3) BLSL-IRSL-TSL. Experiments are performed on beryllium oxide (BeO) dosimeter. Results demonstrate well that the combination of reading modes have direct impact on the TL signal in terms of intensity and glow curve shape. It was also found that when reading modes are correctly combined, particularly when IRSL is applied first, then BLSL and TL, it is possible to collect two or more exploitable signals of different stimulation types for the same irradiation that can be used for different purposes and final applications.


Assuntos
Berílio , Dosimetria Termoluminescente , Berílio/química , Luminescência , Raios Infravermelhos , Medições Luminescentes , Temperatura
11.
Luminescence ; 39(1): e4681, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38286608

RESUMO

In this work, different ion co-doped Mg1-x Al2 O4 nanophosphors, coded as M5Cr-5La A, M5Cr-5Cu A, M0.07Si-0.03Ce A, and M0.05Ti-0.05La A, where 5Cr-5La, 5Cr-5Cu, 0.07Si-0.03Ce, and 0.05Ti-0.05La representing the added ions (mol%), were prepared using the sol-gel method. Phase structure, transmission electron microscope (TEM) images, and element feasibility were checked using X-ray diffraction, TEM analysis, and energy dispersive X-ray (EDX) spectroscopy. Their thermoluminescence (TL) response was checked using a 5 Gy γ-test dose. The M0.05Ti-0.05La A sample was found to be best for the TL response with an ~1.1 times response compared with that of the MTS-700 commercial detector. A wide range of dose-responses for the M0.05Ti-0.05La A sample was found up to a 20 Gy γ-dose with the lowest detectable dose of ⁓23 µGy. Photon attenuation parameter results were Zeff ⁓10, which mean that the M0.05Ti-0.05La A sample could be considered as a near tissue equivalent material. Due to this study, the M0.05Ti-0.05La A sample can be considered as a promising detector for application in personal and medical dosimetric monitoring.


Assuntos
Íons , Luminescência , Íons/química
12.
Am J Otolaryngol ; 45(1): 104026, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37634302

RESUMO

OBJECTIVE: Tracheoesophageal puncture with voice prosthesis (TEP) is considered the gold standard for voice rehabilitation after total laryngectomy; however, there is debate as to whether it should be inserted concurrently with removal of the larynx (primary TEP), or as a separate, additional procedure at a later date (secondary TEP). We utilized the National Surgical Quality Improvement Program Database (NSQIP) to compare postoperative complications, readmission rates, and reoperation rates among individuals who underwent total laryngectomy with or without concurrent TEP placement. METHODS: We conducted a retrospective study using the American College of Surgeons National Surgical Quality Improvement Program database (ACS-NSQIP) from 2012 to 2019. Patients were categorized into primary and non-primary TEP groups using a variation of CPT codes for total laryngectomy, tracheoesophageal prosthesis, and type of reconstruction. Univariate analyses were performed and significance was determined at p < 0.05. RESULTS: A total of 1974 patients who underwent total laryngectomy were identified from the database: 1505 (77.3 %) in the non-primary TEP group and 442 (22.7 %) in the primary TEP group. Patients in the non-primary TEP group were more likely to have an ASA class greater than or equal to three (91.2 % primary vs. 84.6 % non-primary, p < 0.001). Patients in the non-primary TEP group were also more likely to require intraoperative or postoperative blood transfusions within the first 72 h of surgery (20.5 % non-primary vs. 15.3 % primary, p = 0.016). Both groups had similar rates of wound breakdown and dehiscence. There remained no significant difference based on type of reconstruction. CONCLUSIONS: This study suggests that patients receiving primary TEPs are not at a greater risk of developing wound complications such as pharyngocutaneous fistulas in the 30-day postoperative period. This remained true when patients were stratified by type of flap reconstruction. Patients in the non-primary TEP group were more likely to have an ASA category of 3 or greater, which may explain why they experienced higher rates of complications such as blood transfusions intra-operatively or post-operatively.


Assuntos
Neoplasias Laríngeas , Laringe Artificial , Humanos , Laringectomia/métodos , Estudos Retrospectivos , Melhoria de Qualidade , Traqueia/cirurgia , Resultado do Tratamento , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Neoplasias Laríngeas/cirurgia
13.
Sensors (Basel) ; 24(8)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38676236

RESUMO

The overall gain of a scintillation detector is temperature-dependent, leading to a drift in the measured gamma energy spectrum with changes in temperature. To mitigate this effect, a temperature drift correction is essential prior to conducting gamma spectrum analysis. In this study, the detector gain ratio is determined by comparing the positions of the same background peak across different spectra. Subsequently, the original spectrum is adjusted accordingly to obtain a gamma spectrum free from temperature drift. Experimental results demonstrate that after implementing this correction, the relative deviation of the 57Co characteristic peak positions in the gamma spectrum measured by the NaI(Tl) detector is reduced from 18.64% to 0.91%. Furthermore, by performing energy calibration beforehand, the characteristic peak position can be utilized for secondary correction, further minimizing temperature drift. Our findings indicate that the relative deviation of the 22Na characteristic peak positions was reduced, respectively, to 0.51% and 0.46% through secondary correction. This approach, which utilizes the background peak for correction, avoids the need for additional radioactivity or circuitry and effectively mitigates peak drift. Overall, this method holds significant implications for enhancing the accuracy of gamma spectrum analysis.

14.
Sensors (Basel) ; 24(15)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39123888

RESUMO

The efficient fault detection (FD) of traction control systems (TCSs) is crucial for ensuring the safe operation of high-speed trains. Transient faults (TFs) can arise due to prolonged operation and harsh environmental conditions, often being masked by background noise, particularly during dynamic operating conditions. Moreover, acquiring a sufficient number of samples across the entire scenario presents a challenging task, resulting in imbalanced data for FD. To address these limitations, an unsupervised transfer learning (TL) method via federated Cycle-Flow adversarial networks (CFANs) is proposed to effectively detect TFs under various operating conditions. Firstly, a CFAN is specifically designed for extracting latent features and reconstructing data in the source domain. Subsequently, a transfer learning framework employing federated CFANs collectively adjusts the modified knowledge resulting from domain alterations. Finally, the designed federated CFANs execute transient FD by constructing residuals in the target domain. The efficacy of the proposed methodology is demonstrated through comparative experiments.

15.
J Environ Manage ; 353: 120147, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38325278

RESUMO

Aqueous thallium has posed an increasing threat to environment as human's intensified activities in mining, refining, process and discharge. Remediation on thallium pollution has been of up-most importance to water treatment. In present work, MnO2 and magnetic Fe3O4 have been implanted to sodium alginate (SA) in presence of carboxyl methyl cellulose (CMC), and the resultant beads consisted of SA/CMC/MnO2/Fe3O4 were characterized. The materials were applied to treatment of Tl-contaminated water as adsorbent in lab. The removal results revealed that the adsorption capacity reached 38.8 mg (Tl)·g (beads)-1 and almost 100 % removal efficiency was achieved. The residual Tl was below 0.1 µg·L-1, meeting the discharge standard regulated in China. The kinetic adsorption was better described as a pseudo-second-order and three-step intra-particle diffusion model. Freundlich isotherm was well fitted the experimental data. The absorbent shown an excellent competitive specificity (KTl/M: ∼104!) over common hazardous ions Cu2+, Cd2+, Co2+, Pb2+ and Cr3+, as well as naturally abundant K+ and Na+ (KTl/M: 10-102) in mimic environmental conditions. Regeneration and reusability of the absorbent was also verified by five absorption-desorpotion cycles. XPS results revealed that a redox reaction between Mn4+ with Tl+, and an ion exchange of H+ (-O-Fe) and Tl+ were assumed to be main process for the specific capturing. This study provided an efficient SA/CMC/MnO2/Fe3O4 composite beads that could be a promising adsorbent for Tl-polluted water treatment.


Assuntos
Tálio , Poluentes Químicos da Água , Humanos , Compostos de Manganês , Óxidos , Oxirredução , Adsorção , Fenômenos Magnéticos , Poluentes Químicos da Água/análise , Cinética , Concentração de Íons de Hidrogênio
16.
Molecules ; 29(17)2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39274915

RESUMO

Phenylpropanoid sucrose esters are a large and important group of natural substances with significant therapeutic potential. This work describes a pilot study of the enzymatic hydroxycinnamoylation of sucrose and its derivatives which was carried out with the aim of obtaining precursors of natural phenylpropanoid sucrose esters, e.g., vanicoside B. In addition to sucrose, some chemically prepared sucrose acetonides and substituted 3'-O-cinnamates were subjected to enzymatic transesterification with vinyl esters of coumaric, ferulic and 3,4,5-trimethoxycinnamic acid. Commercial enzyme preparations of Lipozyme TL IM lipase and Pentopan 500 BG exhibiting feruloyl esterase activity were tested as biocatalysts in these reactions. The substrate specificity of the used biocatalysts for the donor and acceptor as well as the regioselectivity of the reactions were evaluated and discussed. Surprisingly, Lipozyme TL IM catalyzed the cinnamoylation of sucrose derivatives more to the 1'-OH and 4'-OH positions than to the 6'-OH when the 3'-OH was free and the 6-OH was blocked by isopropylidene. In this case, Pentopan reacted comparably to 1'-OH and 6'-OH positions. If sucrose 3'-O-coumarate was used as an acceptor, in the case of feruloylation with Lipozyme in CH3CN, 6-O-ferulate was the main product (63%). Pentopan feruloylated sucrose 3'-O-coumarate comparably well at the 6-OH and 6'-OH positions (77%). When a proton-donor solvent was used, migration of the 3'-O-cinnamoyl group from fructose to the 2-OH position of glucose was observed. The enzyme hydroxycinnamoylations studied can shorten the targeted syntheses of various phenylpropanoid sucrose esters.


Assuntos
Ácidos Cumáricos , Sacarose , Sacarose/química , Sacarose/metabolismo , Ácidos Cumáricos/química , Ácidos Cumáricos/metabolismo , Lipase/metabolismo , Lipase/química , Cinamatos/química , Cinamatos/metabolismo , Especificidade por Substrato , Esterificação , Hidrolases de Éster Carboxílico/metabolismo , Hidrolases de Éster Carboxílico/química , Ésteres/química , Ésteres/metabolismo , Biocatálise
17.
Environ Monit Assess ; 196(2): 190, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38261087

RESUMO

Soil samples from vegetable farmland in densely populated wards of Nepal were analyzed for natural radionuclide levels, employing a NaI(Tl) 3" [Formula: see text] 3" gamma detector. The study aimed to evaluate the causes of radiation risk, attributing it to soil contamination resulting from the rapid urbanization and concretization that followed the earthquake in 2015. The activity concentration of radium-226, thorium-232, and potassium-40 and the ranges observed are 2.080±0.084-33.675±1.356 Bq kg[Formula: see text], 17.222±0.198-119.949±1.379 Bq kg[Formula: see text], and 11.203 ± 0.325-748.828±21.716 Bq kg[Formula: see text], respectively. The average values obtained for hazard indices are as follows: radium equivalent activity (82.779 Bq kg[Formula: see text]), absorbed dose rate (36.394 nGy h[Formula: see text]), annual effective dose equivalent (0.045 mSv yearr[Formula: see text]), gamma index (0.291), external hazard index (0.224), internal hazard index (0.253), excess lifetime cancer risk (0.159), annual gonadal dose equivalent (243.278 mSv year[Formula: see text]), alpha index (0.054), and activity utilization index (0.716). However, in most places, thorium-232 concentration is greater than those of the world average and recommended values. In specific locations such as Ward 4 in Baluwatar, the soil was found to have concentrations of Ra[Formula: see text] and K[Formula: see text] exceeding recommended limits. Despite this localized concern, the overall analysis of hazard indices across the studied areas revealed that most values were within permissible limits. This suggests that, on a broader scale, radiation exposure may not be a significant concern in the investigated regions. Nonetheless, the study recommends regular monitoring in additional locations to ensure a comprehensive and ongoing assessment of radiation levels.


Assuntos
Terremotos , Monitoramento Ambiental , Tório , Solo , Medição de Risco
18.
Beilstein J Org Chem ; 20: 2242-2253, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39286794

RESUMO

Biocatalysis has established itself as a successful tool in organic synthesis. A particularly fast technique for screening enzymes is the in vitro expression or cell-free protein synthesis (CFPS). The system is based on the transcription and translation machinery of an extract-donating organism to which substrates such as nucleotides and amino acids, as well as energy molecules, salts, buffer, etc., are added. After successful protein synthesis, further substrates can be added for an enzyme activity assay. Although mimicking of cell-like conditions is an approach for optimization, the physical and chemical properties of CFPS are not well described yet. To date, standard conditions have mainly been used for CFPS, with little systematic testing of whether conditions closer to intracellular conditions in terms of viscosity, macromolecules, inorganic ions, osmolarity, or water content are advantageous. Also, very few non-physiological conditions have been tested to date that would expand the parameter space in which CFPS can be performed. In this study, the properties of an Escherichia coli extract-based CFPS system are evaluated, and the parameter space is extended to high viscosities, concentrations of inorganic ion and osmolarity using ten different technical additives including organic solvents, polymers, and salts. It is shown that the synthesis of two model proteins, namely superfolder GFP (sfGFP) and the enzyme truncated human cyclic GMP-AMP synthase fused to sfGFP (thscGAS-sfGFP), is very robust against most of the tested additives.

19.
J Comput Chem ; 44(25): 2016-2029, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37367222

RESUMO

We have investigated the NMR chemical shift of 205 Tl in several thallium compounds, ranging from small covalent Tl(I) and Tl(III) molecules to supramolecular complexes with large organic ligands and some thallium halides. NMR calculations were run at the ZORA relativistic level, with and without spin-orbit coupling using few selected GGA and hybrid functionals, namely BP86, PBE, B3LYP, and PBE0. We also tested solvent effects both at the optimization level and at the NMR calculation step. At the ZORA-SO-PBE0 (COSMO) level of theory we find a very good performance of the computational protocol that allows to discard or retain possible structures/conformations based on the agreement between the calculated chemical shift and the experimental value.

20.
Respir Res ; 24(1): 182, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37434162

RESUMO

Alveolar epithelial barrier is a potential therapeutic target for acute respiratory distress syndrome (ARDS). However, an effective intervention against alveolar epithelial barrier has not been developed. Here, based on single-cell RNA and mRNA sequencing results, death receptor 3 (DR3) and its only known ligand tumor necrosis factor ligand-associated molecule 1A (TL1A) were significantly reduced in epithelium from an ARDS mice and cell models. The apparent reduction in the TL1A/DR3 axis in lungs from septic-ARDS patients was correlated with the severity of the disease. The examination of knockout (KO) and alveolar epithelium conditional KO (CKO) mice showed that TL1A deficiency exacerbated alveolar inflammation and permeability in lipopolysaccharide (LPS)-induced ARDS. Mechanistically, TL1A deficiency decreased glycocalyx syndecan-1 and tight junction-associated zonula occludens 3 by increasing cathepsin E level for strengthening cell-to-cell permeability. Additionally, DR3 deletion aggravated barrier dysfunction and pulmonary edema in LPS-induced ARDS through the above mechanisms based on the analyses of DR3 CKO mice and DR3 overexpression cells. Therefore, the TL1A/DR3 axis has a potential value as a key therapeutic signaling for the protection of alveolar epithelial barrier.


Assuntos
Membro 25 de Receptores de Fatores de Necrose Tumoral , Síndrome do Desconforto Respiratório , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral , Animais , Camundongos , Epitélio , Ligantes , Síndrome do Desconforto Respiratório/induzido quimicamente , Síndrome do Desconforto Respiratório/genética , Fator de Necrose Tumoral alfa , Membro 25 de Receptores de Fatores de Necrose Tumoral/genética , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética
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