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1.
Pathol Res Pract ; 263: 155624, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39357190

RESUMEN

INTRODUCTION: Benign fibro-osseous lesions have long been an area of diagnostic difficulty due to overlapping of histological and radiological features. Differentiating between these lesions is crucial because of their unique pathogenesis and biological behavior. Ossifying fibroma (OF) and fibrous dysplasia (FD) are the most prevalent lesions. However, not all FD or OF exhibit the typical radiological and histopathological features. In such situations, molecular-level investigations could be essential for precise identification and differentiation. AIM: To evaluate the screening of GNAS and CDC73 mutations in blood and formalin fixed tumor tissues (FFTT) of FD and OF cases. MATERIAL AND METHODS: Six blood samples (three cases of FD and JOF each) and thirteen FFTT (six cases of FD and seven cases of JOF) were included in the study. DNA was extracted from peripheral blood samples using salting out method followed by whole exome sequencing. Multiple efforts were made to extract DNA from tumor tissues using various protocols, but no measurable yield was obtained. RESULTS: DNA derived from blood samples gave successful DNA library preparation and subsequent exome sequencing data generation. We report a pathogenic GNAS mutation (exon8:c.G602A:p.R201H) associated with McCune-Albright syndrome and a novel benign mutation identified in a case of FD (GNAS(NM_000516.7):c.257+687_257+688del) whereas none of the subjects of JOF displayed GNAS and/or CDC73 mutation. CONCLUSION: Study observed mutations in GNAS gene in blood samples from FD cases. However, a limitation is that only DNA extracted from blood underwent successful exome sequencing. Potential reason for low-quality DNA extraction from tissue may be attributed to prior fixation procedures conducted on bone specimens.

2.
bioRxiv ; 2024 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-39229147

RESUMEN

Palladin is an actin binding protein that accelerates actin polymerization and is linked to metastasis of several types of cancer. Previously, three lysine residues in an immunoglobulin-like domain of palladin have been identified as essential for actin binding. However, it is still unknown where palladin binds to F-actin. Evidence that palladin binds to the sides of actin filaments to facilitate branching is supported by our previous study showing that palladin was able to compensate for Arp2/3 in the formation of Listeria actin comet tails. Here, we used chemical crosslinking to covalently link palladin and F-actin residues based on spatial proximity. Samples were then enzymatically digested, separated by liquid chromatography, and analyzed by tandem mass spectrometry. Peptides containing the crosslinks and specific residues involved were then identified for input to HADDOCK docking server to model the most likely binding conformation. Small angle X-ray scattering was used to provide further insight into palladin flexibility and the binding interface, and NMR spectra identified potential interactions between palladin's Ig domains. Our final structural model of the F-actin:palladin complex revealed how palladin interacts with and stabilizes F-actin at the interface between two actin monomers. Three actin residues that were identified in this study also appear commonly in the actin binding interface with other proteins such as myotilin, myosin, and tropomodulin. An accurate structural representation of the complex between palladin and actin extends our understanding of palladin's role in promoting cancer metastasis through regulation of actin dynamics. Significance: In this study we have combined various advanced structural biology techniques to provide the first comprehensive model of the palladin-actin complex. Considering palladin's role in cancer cell metastasis, this structure could be useful in screening and developing chemotherapeutic agents that target this interaction and prevent cancer cell metastasis.

3.
Microbiol Spectr ; : e0110624, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39315783

RESUMEN

For bacteria, an intricate coordination between sensing and regulating iron levels and managing oxidative stress is required as their levels are tightly interlinked. While various oxidative stress and heme-based redox sensors have been reported for both pathogenic and non-pathogenic bacteria, the mechanisms governing the modulation of intracellular iron levels in response to changes in redox status remain unclear. In this study, a gene-inactivated strain of mycobacterial sensor kinase PdtaS showed dysregulated expression of genes associated with iron metabolism, including Fe-S clusters, NADH dehydrogenases, and iron uptake. The strain showed poor growth in nutrient-limiting conditions, a defect rescuable by heme but not by Fe3+ supplementation. This observation was associated with the PAS domain of the PdtaS sensor kinase. Biochemical and biophysical experiments established heme-binding to the PAS domain and its inhibitory effect on PdtaS auto-kinase activity, suggesting that the absence of heme induces activation of this sensor kinase. Interestingly, despite having an endogenous heme biosynthetic pathway or even external heme supplementation, the ∆pdtaS mutant exhibited persistent low intracellular iron levels concomitant with elevated oxidative stress. Antioxidant supplementation mitigated growth defects, emphasizing the link between oxidative stress, intracellular iron levels, and PdtaS activity. RNA-IP identified key targets associated with redox homeostasis and iron metabolism as targets of the PdtaR response regulator. The study proposes a novel role for the PdtaS-PdtaR TCS in sensing heme, regulation of intracellular iron levels, and redox balance.IMPORTANCEThe research article investigates the intricate interplay between bacteria's ability to take and utilize iron without inducing excess iron's toxic effects, including oxidative stress. The study shows that bacteria achieve this by sensing intracellular iron available as heme through a sensory protein PdtaS, which turns off when heme is in excess and prevents iron uptake and iron efflux. The process shields bacteria from generating Fe-dependent free radicals and allows it to maintain viability. The absence of sensor kinase abrogates all these processes, increasing bacteria susceptibility to ROS and thereby slowing growth. This feature of the sensor kinase PdtaS makes it an attractive co-therapeutic target for tuberculosis therapy, where its inhibition will prevent iron uptake, even in the presence of low iron, thereby halting bacterial proliferation.

4.
J Clin Lipidol ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-39278778

RESUMEN

Rapid reduction of low-density lipoprotein cholesterol (LDL-C) to target levels immediately following acute coronary syndrome (ACS) event is critical to prevent future events. High-dose statins alone often fail to achieve LDL-C goals. Proprotein convertase subtilisin/kexin type-9 inhibitors (PCSK9i) combined with high-dose statins improves LDL-C goal attainment, but is unaffordable for many patients in India and worldwide. In a real-world open-label study, we demonstrated in a cohort of 122 patients with ACS, concurrent triple therapy with rosuvastatin 40 mg/d, ezetimibe 10 mg/d, and bempedoic acid 180 mg/d (REB) started at the time of hospital admission was associated with 57.7%, 61.7%, 61.9% and 60.6% reductions in LDL-C from 115.6 mg/dL at baseline to 48.9 mg/dL at week 1, 44.3 mg/dL at week 2, 44.1 mg/dL at week 4, and 45.6 mg/dL at week 6, respectively (each p < 0.001 compared to baseline; p < 0.001 across repeated measures). REB provided significant reductions in LDL-C within as early as one week and enabled 76.3% and 92.2% of patients to achieve the Lipid Association of India and American College of Cardiology recommended LDL-C targets of <50 mg/dl and <70 mg/dl within 2-weeks, respectively, which were sustained at 4-6 weeks. REB was generally well tolerated. Our study demonstrates the capacity to rapidly achieve LDL-C goals after ACS with triple REB therapy, an affordable regimen in India.

5.
Dalton Trans ; 53(34): 14139-14143, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39145492

RESUMEN

A series of boron difluoro bis(diiminate) complexes have been prepared and used to obtain triflate substituted fluoroborane complexes. The corresponding well-defined bis(borenium) cations were subsequently synthesized and structurally authenticated. We are also presenting the first experimental and theoretical study of bis(borenium) cations that are derivative of cationic borinic acid.

6.
Food Res Int ; 186: 114344, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38729696

RESUMEN

The research aimed to evaluate the effect of ultrasonication and succinylation on the functional, iron binding, physiochemical, and cellular mineral uptake efficacy of chickpea protein concentrate. Succinylation resulted in significant improvements in the water-holding capacity (WHC) (25.47 %), oil-holding capacity (OHC) (31.38 %), and solubility (5.80 %) of the chickpea protein-iron complex. Mineral bioavailability significantly increased by 4.41 %, and there was a significant increase in cellular mineral uptake (64.64 %), retention (36.68 %), and transport (27.96 %). The ferritin content of the succinylated chickpea protein-iron complex showed a substantial increase of 66.31%. Furthermore, the dual modification approach combining ultrasonication and succinylation reduced the particle size of the protein-iron complex with a substantial reduction of 83.25 %. It also resulted in a significant enhancement of 51.5 % in the SH (sulfhydryl) content and 48.92 % in the surface hydrophobicity. Mineral bioavailability and cellular mineral uptake, retention, and transport were further enhanced through dual modification. In terms of application, the addition of single and dual-modified chickpea protein-iron complex to a fruit-based smoothie demonstrated positive acceptance in sensory attributes. Overall, the combined approach of succinylation and ultrasonication to the chickpea protein-iron complex shows a promising strategy for enhancing the physiochemical and techno-functional characteristics, cellular mineral uptake, and the development of vegan food products.


Asunto(s)
Disponibilidad Biológica , Cicer , Hierro , Cicer/química , Hierro/química , Hierro/metabolismo , Humanos , Alimentos Fortificados , Proteínas de Plantas/química , Digestión , Minerales/química , Células CACO-2 , Ácido Succínico/química , Tamaño de la Partícula , Manipulación de Alimentos/métodos , Solubilidad , Ferritinas/química , Ferritinas/metabolismo
7.
Sci Rep ; 14(1): 11898, 2024 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-38789479

RESUMEN

We have previously reported the transcriptomic and lipidomic profile of the first-generation, hygromycin-resistant (HygR) version of the BCGΔBCG1419c vaccine candidate, under biofilm conditions. We recently constructed and characterized the efficacy, safety, whole genome sequence, and proteomic profile of a second-generation version of BCGΔBCG1419c, a strain lacking the BCG1419c gene and devoid of antibiotic markers. Here, we compared the antibiotic-less BCGΔBCG1419c with BCG. We assessed their colonial and ultrastructural morphology, biofilm, c-di-GMP production in vitro, as well as their transcriptomic and lipidomic profiles, including their capacity to activate macrophages via Mincle and Myd88. Our results show that BCGΔBCG1419c colonial and ultrastructural morphology, c-di-GMP, and biofilm production differed from parental BCG, whereas we found no significant changes in its lipidomic profile either in biofilm or planktonic growth conditions. Transcriptomic profiling suggests changes in BCGΔBCG1419c cell wall and showed reduced transcription of some members of the DosR, MtrA, and ArgR regulons. Finally, induction of TNF-α, IL-6 or G-CSF by bone-marrow derived macrophages infected with either BCGΔBCG1419c or BCG required Mincle and Myd88. Our results confirm that some differences already found to occur in HygR BCGΔBCG1419c compared with BCG are maintained in the antibiotic-less version of this vaccine candidate except changes in production of PDIM. Comparison with previous characterizations conducted by OMICs show that some differences observed in BCGΔBCG1419c compared with BCG are maintained whereas others are dependent on the growth condition employed to culture them.


Asunto(s)
Vacuna BCG , Biopelículas , GMP Cíclico , Lipidómica , Macrófagos , Mycobacterium bovis , Factor 88 de Diferenciación Mieloide , Transcriptoma , Animales , Factor 88 de Diferenciación Mieloide/metabolismo , Factor 88 de Diferenciación Mieloide/genética , Ratones , Macrófagos/metabolismo , Macrófagos/inmunología , Vacuna BCG/inmunología , GMP Cíclico/metabolismo , GMP Cíclico/análogos & derivados , Mycobacterium bovis/genética , Mycobacterium bovis/inmunología , Biopelículas/crecimiento & desarrollo , Citocinas/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Perfilación de la Expresión Génica , Lectinas Tipo C
8.
Adv Sci (Weinh) ; 11(25): e2308561, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38590131

RESUMEN

Underwater organisms exhibit sophisticated propulsion mechanisms, enabling them to navigate fluid environments with exceptional dexterity. Recently, substantial efforts have focused on integrating these movements into soft robots using smart shape-changing materials, particularly by using light for their propulsion and control. Nonetheless, challenges persist, including slow response times and the need of powerful light beams to actuate the robot. This last can result in unintended sample heating and potentially necessitate tracking specific actuation spots on the swimmer. To tackle these challenges, new azobenzene-containing photopolymerizable inks are introduced, which can be processed by extrusion printing into liquid crystalline elastomer (LCE) elements of precise shape and morphology. These LCEs exhibit rapid and significant photomechanical response underwater, driven by moderate-intensity ultraviolet (UV) and green light, being the actuation mechanism predominantly photochemical. Inspired by nature, a biomimetic four-lapped ephyra-like LCE swimmer is printed. The periodically illumination of the entire swimmer with moderate-intensity UV and green light, induces synchronous lappet bending toward the light source and swimmer propulsion away from the light. The platform eliminates the need of localized laser beams and tracking systems to monitor the swimmer's motion through the fluid, making it a versatile tool for creating light-fueled robotic LCE free-swimmers.

9.
Langmuir ; 40(12): 6172-6186, 2024 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-38467540

RESUMEN

Conformational changes play a seminal role in modulating the activity of proteins. This concept becomes all the more relevant in the context of metalloproteins, owing to the formation of specific conformation(s) induced by internal perturbations (like a change in pH, ligand binding, or receptor binding), which may carry out the binding and release of the metal ion/ions from the metal binding center of the protein. Herein, we investigated the conformational changes of an iron-binding protein, monoferric human serum transferrin (Fe-hTF), using several spectroscopic approaches. We could reversibly tune the cetyltrimethylammonium bromide (CTAB)-induced conformation of the protein, exploiting the concept of mixed micelles formed by three sequestrating agents: (3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate) hydrate (CHAPS) and two bile salts, namely, sodium cholate (NaC) and sodium deoxycholate (NaDC). The formation of mixed micelles between CTAB and these reagents (CHAPS/NaC/NaDC) results in the sequestration of CTAB molecules from the protein environment and aids the protein in reattaining its native-like structure. However, the guanidinium hydrochloride-induced denatured Fe-hTF did not acquire its native-like structure using these sequestrating agents, which substantiates the exclusive role of mixed micelles in the present study. Apart from this, we found that the conformation of transferrin (adopted in the presence of CTAB) displays pronounced esterase-like activity toward the para-nitrophenyl acetate (PNPA) substrate as compared to native transferrin. We also outlined the impact of the iron center and amino acids surrounding the iron center on the effective catalytic activity in the CTAB medium. We estimated ∼3 times higher specific catalytic efficiency for the iron-depleted Apo-hTF compared to the fully iron-saturated Fe2-hTF in the presence of CTAB.


Asunto(s)
Hierro , Micelas , Humanos , Hierro/química , Cetrimonio , Transferrina/química , Unión Proteica
10.
Diagn Microbiol Infect Dis ; 109(2): 116281, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38537507

RESUMEN

These diverse outcomes of Covid-19 are influenced by various factors including age, gender, underlying health conditions, immune responses, viral variants, external factors, and overall quality of life. Demographic analysis of patients aged 0-18 years experienced mild to moderate cases, above 55 years with co-morbidities, were more severely affected.COVID-19 incidence was higher in males (58 %) & (42 %) in females. The reduced expression of Toll-like receptors (TLR) in severe and critical patients is a crucial determinant. This reduced TLR expression is primarily attributed to the dominance of the PLpro viral protein of COVID-19. Disease enrichment analysis highlights the long-term impact of COVID-19, which can lead to post-recovery complications such as hypertension, diabetes, cardiac diseases, and brain ischemia in Covid-19 patients. In conclusion, a comprehensive strategy targeting key factors like PLpro, TLR, and inflammatory cytokines such as IL-1 and IL-6 could offer an effective approach to mitigate the devastating effects of COVID-19.


Asunto(s)
COVID-19 , SARS-CoV-2 , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Adulto Joven , COVID-19/inmunología , Citocinas/inmunología , Citocinas/sangre , SARS-CoV-2/inmunología , Receptores Toll-Like/inmunología , Estudios Retrospectivos
11.
JNMA J Nepal Med Assoc ; 62(270): 155-157, 2024 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-38409970

RESUMEN

Zellweger syndrome is an autosomal recessive disease within the spectrum of peroxisome biogenesis disorder manifesting in the neonatal period with profound dysfunction of the central nervous system, liver and kidney. Common clinical presentations include hypotonia, seizure, hepatomegaly, craniofacial dysmorphism and early death. Mutation in one of the PEX genes coding for a peroxisome assembly protein creates a functionally incompetent organelle causing accumulation of very long chain fatty acids in various organs. Here we report the case of a 5-month-old male presented at birth with hypotonia, poor feeding, gross congenital anomalies and later during early infancy with failure to thrive, several episodes of seizures, aspiration due to feeding difficulties and recurrent severe pneumonia. A whole genomic sequencing brought us to the final diagnosis of Zellweger syndrome. Despite an absence of treatment options, prompt diagnosis of Zellweger syndrome is important for providing appropriate symptomatic care, definitive genetic testing and prenatal counselling. Keywords: case reports; mutation; neonate; Zellweger syndrome.


Asunto(s)
Trastorno Peroxisomal , Síndrome de Zellweger , Recién Nacido , Humanos , Masculino , Lactante , Síndrome de Zellweger/diagnóstico , Síndrome de Zellweger/genética , Hipotonía Muscular/genética , Trastorno Peroxisomal/genética , Pruebas Genéticas , Mutación
12.
Br J Oral Maxillofac Surg ; 62(2): 164-170, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38310027

RESUMEN

Temporomandibular joint (TMJ) ankylosis leads to mandibular micrognathia that severely collapses the upper airway causing obstructive sleep apnoea (OSA), resulting in deterioration and compromise in the quality of life (QoL) of patients. In this study, we aimed to calculate airway volume changes, apnoea-hypopnoea index (AHI), and improvement in quality of life before and after distraction osteogenesis (DO). Fourteen Patients with OSA secondary to TMJ ankylosis at a mean (SD) age of 17.5 (5.43) years were enrolled in this prospective study. Multivector mandibular distractors were used in all patients following the standard Ilizarov distraction protocol with a mean (SD) anteroposterior distraction of 16.21 (4.37) mm and a consolidation period of 116.92 (14.35) days. The patients were followed up for six months. A polysomnography test (PSG) was done to quantify AHI and a low-dose computed tomographic scan was done to calculate airway volume using Dolphin medical imaging software pre and post-DO. The QoL of the patients was calculated using the OSA-18 questionnaire. Results analysis depicted that the mean (SD) preoperative AHI was 51.44 (37.99)/h which was improved to 9.57 (9.74)/h (p = 0.001) after DO. Airway volume was calculated on Dolphin software before and after DO showed a significant improvement in airway volume by 121.12% (98.30)%. Similarly, the OSA-18 questionnaire showed significant improvement in QoL from severe to normal. This study suggested that DO increases the corpus length of the mandible, leading to an increment in airway volume, which improves the QoL.


Asunto(s)
Anquilosis , Delfines , Osteogénesis por Distracción , Apnea Obstructiva del Sueño , Trastornos de la Articulación Temporomandibular , Humanos , Animales , Adolescente , Calidad de Vida , Estudios Prospectivos , Apnea Obstructiva del Sueño/etiología , Apnea Obstructiva del Sueño/cirugía , Anquilosis/complicaciones , Anquilosis/cirugía , Articulación Temporomandibular
14.
Food Chem ; 445: 138671, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38367556

RESUMEN

Chickpea protein, a valuable plant-based source, offers versatile applications, yet the impact of modifications like succinylation and ultrasonication on its properties remains unclear. This study explored dual succinylation and ultrasonication modification to enhance its functionality and application. Modified chickpea protein with a degree of succinylation of 96.75 %, showed enhanced water holding capacity 39.83 %, oil holding capacity 54.02 %, solubility 7.20 %, and emulsifying capacity 23.17 %, compared to native protein. Despite reduced amino acid content (64.50 %), particularly lysine, succinylation increased sulfhydryl by 1.74 %, reducing hydrophobicity (Ho) by 41.87 % and causing structural changes. Ultrasonication further reduced particle size by 82.57 % and increased zeta potential and amino acid content (57.47 %). The dual-modified protein exhibited a non-significant increase in antimicrobial activity against Staphylococcus aureus (25.93 ± 1.36 mm) compared to the native protein (25.28 ± 1.05 mm). In conclusion, succinylation combined with ultrasonication offers a promising strategy to enhance chickpea protein's physicochemical properties for diverse applications.


Asunto(s)
Aminoácidos , Cicer , Aminoácidos/metabolismo , Cicer/química , Proteínas/metabolismo , Solubilidad , Agua/metabolismo
16.
Artículo en Inglés | MEDLINE | ID: mdl-38176095

RESUMEN

Isolation of Extracellular Vesicles (EVs) has been done extensively in the past using ultracentrifugation, a recent shift has been observed towards precipitation, and exosome isolation kits. These methods often co-elute contaminants of similar size and density which makes their detection and downstream applications quite challenging. As well as the EV yield is also compromised in some methodologies due to aggregate formation. In recent reports, size-exclusion chromatography (SEC) is replacing density gradient-based ultracentrifugation as the gold standard of exosome isolation. It outperforms in yield, purity and does not account for any physical damage to the EVs. We have standardized the methodology for an efficient pure yield of homogenous exosomes of size even smaller than 75 nm in Caenorhabditis elegans homogenate. The paper entails the application and optimization of EV isolation by SEC based on previous studies by optimizing bed size and type of sepharose column employed. We propose that this method is economically feasible in comparison with currently available approaches. A comparative study was conducted to investigate the performance of CL-6B in relation to CL-2B and further, this was combined with ultracentrifugation for higher efficacy. The methodology could be introduced in a clinical setting due to its therapeutic potential and scope. The eluted EVs were studied by flow cytometry, nanotracking and characterized for size and morphology.


Asunto(s)
Exosomas , Vesículas Extracelulares , Animales , Caenorhabditis elegans , Vesículas Extracelulares/química , Ultracentrifugación/métodos , Cromatografía en Gel
17.
Biogerontology ; 25(4): 627-647, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38240923

RESUMEN

The influence of chronic diseases on various facets of macrophage cellular senescence is poorly understood. This study evaluated the impact of chronic hyperglycemia on the induction of cellular senescence and subsequent immunosurveillance functions in RAW264.7 macrophages. Macrophages were cultured under normal glucose (NG; 5 mM), high glucose (HG; 20 mM), and very high glucose (VHG; 40 mM) conditions and assessed for markers of cellular senescence. Hyperglycemia induced strong upregulation of SA-ß-gal activity, and loss of PCNA and Lamin B1 gene expression while markers of cell cycle arrest generally decreased. Non-significant changes in SASP-related proteins were observed while ROS levels slightly decreased and mitochondrial membrane potential increased. Protein concentration on the exosome membrane surface and their stability appeared to increase under hyperglycemic conditions. However, when macrophages were exposed to the secretory media (SM) of senescent preadipocytes, a dramatic increase in the levels of all inflammatory proteins was recorded especially in the VHG group that was also accompanied by upregulation of NF-κB and NLRP3 gene expression. SM treatment to hyperglycemic macrophages activated the TLR-2/Myd88 pathway but decreased the expression of scavenger receptors RAGE, CD36, and Olr-1 while CD44 and CXCL16 expression increased. On exposure to LPS, a strong upregulation in NO, ROS, and inflammatory cytokines was observed. Together, these results suggest that primary markers of cellular senescence are aberrantly expressed under chronic hyperglycemic conditions in macrophages with no significant SASP activation. Nonetheless, hyperglycemia strongly deregulates macrophage functions leading to impaired immunosurveillance of senescent cells and aggravation of inflamm-aging. This work provides novel insights into how hyperglycemia-induced dysfunctions can impact the potency of macrophages to manage senescent cell burden in aging tissues.


Asunto(s)
Senescencia Celular , Glucosa , Macrófagos , Animales , Senescencia Celular/efectos de los fármacos , Ratones , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Glucosa/metabolismo , Células RAW 264.7 , Hiperglucemia/metabolismo , Hiperglucemia/inmunología , Biomarcadores/metabolismo , Vigilancia Inmunológica , Especies Reactivas de Oxígeno/metabolismo
18.
Med J Armed Forces India ; 80(1): 1-3, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38239599
19.
Chem Commun (Camb) ; 60(13): 1663-1673, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38260953

RESUMEN

Beryllium possesses a unique amalgamation of characteristics, its electronegativity included, that not only make it a vital component in a wide range of technical sectors and consumer industries, but also make it an interesting candidate for forming covalently bonded compounds. However, the extremely toxic nature of beryllium, which can cause chronic beryllium disease, has limited the exploration of its chemistry, making beryllium one of the least studied (non-radioactive) elements. The development of selective chelating ligands, sterically encumbered substituents and, moreover, the boom of N-heterocyclic carbenes in organometallic chemistry and main group chemistry has revived the interest in beryllium chemistry. Therefore, some quite remarkable progress in the coordination and organometallic chemistry of beryllium has been made in the last two decades. For example, low oxidation state beryllium compounds, antiaromatic/aromatic beryllium compounds, where beryllium is involved in π-electron delocalization, and the isolation of beryllium-beryllium bonded species have all been achieved. This article provides an oversight over the recent developments in the organometallic chemistry of beryllium.

20.
Nanoscale ; 16(2): 806-820, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38090989

RESUMEN

The core and the ligand shell of metal nanoclusters (MNCs) have an influential role in modulating their spectroscopic signatures and catalytic properties. The aspect of electrostatic interactions to regulate the catalytic properties of MNCs has not been comprehensively addressed to date. Our present work conclusively delineates the role of the metal core and the electrostatic surface of MNCs involved in the reduction of nitroarenes. A facile surface modification of mercaptosuccinic acid (MSA)-templated AgNCs has been selectively achieved through Mg2+ ions (Mg-AgNCs). Microscopic studies suggest that the size of Mg-AgNCs is ∼3.3 nm, which is considerably higher than that of MSA-templated AgNCs (∼1.75 nm), confirming the formation of a nano-assembled structure. Our spectroscopic and microscopic experiments revealed that the negatively charged AgNCs efficiently catalyze the reduction of 4-nitrophenol (4-NP) with a rate constant of 0.23 ± 0.01 min-1. However, upon surface modification, the catalytic efficiency almost doubles due to the formation of Mg-AgNCs. Catalysis through AgNCs and Mg-AgNCs collectively portrays the role of the core and electrostatic surfaces. Furthermore, the role of electrostatic interaction has been substantiated by varying the ionic strength of the medium, as well as employing different molecular systems. A quantitative assessment of the Debye screening length asserts the correlation between the ionic strength of the medium and the role of electrostatic interactions involved herein. This highly enhanced catalytic aspect has been utilized for the real sample analysis, wherein AgNCs unexpectedly outperform Mg-AgNCs. This approach of real sample analysis also emanates the role of electrostatics involved. This comprehensive investigation represents the influential role of the core and ligand shell of MNCs as well as the role of electrostatics on its catalytic activities, which is relevant for the rational design of highly efficient catalysts.

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