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1.
Cell ; 166(6): 1411-1422.e16, 2016 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-27610567

RESUMEN

A complete, 52-protein, 2.5 million dalton, Mediator-RNA polymerase II pre-initiation complex (Med-PIC) was assembled and analyzed by cryo-electron microscopy and by chemical cross-linking and mass spectrometry. The resulting complete Med-PIC structure reveals two components of functional significance, absent from previous structures, a protein kinase complex and the Mediator-activator interaction region. It thereby shows how the kinase and its target, the C-terminal domain of the polymerase, control Med-PIC interaction and transcription.


Asunto(s)
Complejo Mediador/química , Complejo Mediador/metabolismo , Modelos Moleculares , ARN Polimerasa II/química , ARN Polimerasa II/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/enzimología , Saccharomyces cerevisiae/genética , Microscopía por Crioelectrón , Regulación de la Expresión Génica , Espectrometría de Masas , Fosforilación , Estructura Terciaria de Proteína , Subunidades de Proteína/química , Subunidades de Proteína/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
2.
RNA ; 29(2): 188-199, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36400447

RESUMEN

Parasitic protozoans of the Trypanosoma and Leishmania species have a uniquely organized mitochondrial genome, the kinetoplast. Most kinetoplast-transcribed mRNAs are cryptic and encode multiple subunits for the electron transport chain following maturation through a uridine insertion/deletion process called RNA editing. This process is achieved through an enzyme cascade by an RNA editing catalytic complex (RECC), where the final ligation step is catalyzed by the kinetoplastid RNA editing ligases, KREL1 and KREL2. While the amino-terminal domain (NTD) of these proteins is highly conserved with other DNA ligases and mRNA capping enzymes, with five recognizable motifs, the functional role of their diverged carboxy-terminal domain (CTD) has remained elusive. In this manuscript, we assayed recombinant KREL1 in vitro to unveil critical residues from its CTD to be involved in protein-protein interaction and dsRNA ligation activity. Our data show that the α-helix (H)3 of KREL1 CTD interacts with the αH1 of its editosome protein partner KREPA2. Intriguingly, the OB-fold domain and the zinc fingers on KREPA2 do not appear to influence the RNA ligation activity of KREL1. Moreover, a specific KWKE motif on the αH4 of KREL1 CTD is found to be implicated in ligase auto-adenylylation analogous to motif VI in DNA ligases. In summary, we present in the KREL1 CTD a motif VI for auto-adenylylation and a KREPA2 binding motif for RECC integration.


Asunto(s)
Trypanosoma brucei brucei , Trypanosoma , Ligasas , Edición de ARN , Trypanosoma brucei brucei/metabolismo , Trypanosoma/metabolismo , Proteínas/genética , ARN Polimerasa Dependiente del ARN/genética , ADN Ligasas/metabolismo , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo
3.
EMBO Rep ; 24(9): e56150, 2023 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-37424514

RESUMEN

The largest subunit of RNA polymerase (Pol) II harbors an evolutionarily conserved C-terminal domain (CTD), composed of heptapeptide repeats, central to the transcriptional process. Here, we analyze the transcriptional phenotypes of a CTD-Δ5 mutant that carries a large CTD truncation in human cells. Our data show that this mutant can transcribe genes in living cells but displays a pervasive phenotype with impaired termination, similar to but more severe than previously characterized mutations of CTD tyrosine residues. The CTD-Δ5 mutant does not interact with the Mediator and Integrator complexes involved in the activation of transcription and processing of RNAs. Examination of long-distance interactions and CTCF-binding patterns in CTD-Δ5 mutant cells reveals no changes in TAD domains or borders. Our data demonstrate that the CTD is largely dispensable for the act of transcription in living cells. We propose a model in which CTD-depleted Pol II has a lower entry rate onto DNA but becomes pervasive once engaged in transcription, resulting in a defect in termination.


Asunto(s)
ARN Polimerasa II , Transcripción Genética , Humanos , ARN Polimerasa II/metabolismo , Núcleo Celular/metabolismo , Mutación , Fosforilación
4.
J Biol Chem ; 299(7): 104912, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37307916

RESUMEN

α-synuclein (αS) is an abundant, neuronal protein that assembles into fibrillar pathological inclusions in a spectrum of neurodegenerative diseases that include Lewy body diseases (LBD) and Multiple System Atrophy (MSA). The cellular and regional distributions of pathological inclusions vary widely between different synucleinopathies contributing to the spectrum of clinical presentations. Extensive cleavage within the carboxy (C)-terminal region of αS is associated with inclusion formation, although the events leading to these modifications and the implications for pathobiology are of ongoing study. αS preformed fibrils can induce prion-like spread of αS pathology in both in vitro and animal models of disease. Using C truncation-specific antibodies, we demonstrated here that prion-like cellular uptake and processing of αS preformed fibrils resulted in two major cleavages at residues 103 and 114. A third cleavage product (122 αS) accumulated upon application of lysosomal protease inhibitors. In vitro, both 1-103 and 1-114 αS polymerized rapidly and extensively in isolation and in the presence of full-length αS. 1-103 αS also demonstrated more extensive aggregation when expressed in cultured cells. Furthermore, we used novel antibodies to αS cleaved at residue Glu114, to assess x-114 αS pathology in postmortem brain tissue from patients with LBD and MSA, as well as three different transgenic αS mouse models of prion-like induction. The distribution of x-114 αS pathology was distinct from that of overall αS pathology. These studies reveal the cellular formation and behavior of αS C-truncated at residues 114 and 103 as well as the disease dependent distribution of x-114 αS pathology.


Asunto(s)
Enfermedad por Cuerpos de Lewy , Atrofia de Múltiples Sistemas , alfa-Sinucleína , Animales , Ratones , alfa-Sinucleína/química , alfa-Sinucleína/metabolismo , Ratones Transgénicos , Atrofia de Múltiples Sistemas/metabolismo , Atrofia de Múltiples Sistemas/patología , Priones/química , Priones/metabolismo , Humanos , Lisosomas/enzimología , Inhibidores de Proteasas , Enfermedad por Cuerpos de Lewy/metabolismo , Enfermedad por Cuerpos de Lewy/patología , Autopsia , Ácido Glutámico/metabolismo
5.
Antimicrob Agents Chemother ; 68(5): e0009324, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38597636

RESUMEN

Capillary samples offer practical benefits compared with venous samples for the measurement of drug concentrations, but the relationship between the two measures varies between different drugs. We measured the concentrations of lumefantrine, mefloquine, piperaquine in 270 pairs of venous plasma and concurrent capillary plasma samples collected from 270 pregnant women with uncomplicated falciparum or vivax malaria. The median and range of venous plasma concentrations included in this study were 447.5 ng/mL (8.81-3,370) for lumefantrine (day 7, n = 76, median total dose received 96.0 mg/kg), 17.9 ng/mL (1.72-181) for desbutyl-lumefantrine, 1,885 ng/mL (762-4,830) for mefloquine (days 3-21, n = 90, median total dose 24.9 mg/kg), 641 ng/mL (79.9-1,950) for carboxy-mefloquine, and 51.8 ng/mL (3.57-851) for piperaquine (days 3-21, n = 89, median total dose 52.2 mg/kg). Although venous and capillary plasma concentrations showed a high correlation (Pearson's correlation coefficient: 0.90-0.99) for all antimalarials and their primary metabolites, they were not directly interchangeable. Using the concurrent capillary plasma concentrations and other variables, the proportions of venous plasma samples predicted within a ±10% precision range was 34% (26/76) for lumefantrine, 36% (32/89) for desbutyl-lumefantrine, 74% (67/90) for mefloquine, 82% (74/90) for carboxy-mefloquine, and 24% (21/89) for piperaquine. Venous plasma concentrations of mefloquine, but not lumefantrine and piperaquine, could be predicted by capillary plasma samples with an acceptable level of agreement. Capillary plasma samples can be utilized for pharmacokinetic and clinical studies, but caution surrounding cut-off values is required at the individual level.CLINICAL TRIALSThis study is registered with ClinicalTrials.gov as NCT01054248.


Asunto(s)
Antimaláricos , Lumefantrina , Malaria Falciparum , Malaria Vivax , Mefloquina , Piperazinas , Quinolinas , Humanos , Femenino , Mefloquina/sangre , Mefloquina/uso terapéutico , Mefloquina/farmacocinética , Antimaláricos/sangre , Antimaláricos/uso terapéutico , Antimaláricos/farmacocinética , Embarazo , Quinolinas/sangre , Quinolinas/farmacocinética , Quinolinas/uso terapéutico , Lumefantrina/uso terapéutico , Lumefantrina/sangre , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/sangre , Adulto , Malaria Vivax/tratamiento farmacológico , Malaria Vivax/sangre , Adulto Joven , Etanolaminas/sangre , Etanolaminas/farmacocinética , Etanolaminas/uso terapéutico , Fluorenos/sangre , Fluorenos/uso terapéutico , Fluorenos/farmacocinética , Adolescente
6.
Chemistry ; 30(55): e202402285, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38987225

RESUMEN

The photoinduced regioselective HAT reactions of acetals, ethers, and alcohols using benzoic acids in a two-molecule photoredox system led to the formation of new C-C bonds with alkenes under mild conditions. Aryl carboxy radicals generated from benzoic acids in a two-molecule photoredox system can function as catalytic HAT reagents, even though an excess amount of a hydrogen donor substrate is required. Various acetals, ethers, alcohols, and alkenes can be employed in the photoreaction to provide both high yields of adducts and high recoveries of benzoic acids.

7.
Mol Pharm ; 21(9): 4589-4602, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39088435

RESUMEN

Amorphous solid dispersion (ASD) in a polymer matrix is a powerful method for enhancing the solubility and bioavailability of otherwise crystalline, poorly water-soluble drugs. 6-Carboxycellulose acetate butyrate (CCAB) is a relatively new commercial cellulose derivative that was introduced for use in waterborne coating applications. As CCAB is an amphiphilic, carboxyl-containing, high glass transition temperature (Tg) polymer, characteristics essential to excellent ASD polymer performance, we chose to explore its ASD potential. Structurally diverse drugs quercetin, ibuprofen, ritonavir, loratadine, and clarithromycin were dispersed in CCAB matrices. We evaluated the ability of CCAB to create ASDs with these drugs and its ability to provide solubility enhancement and effective drug release. CCAB/drug dispersions prepared by spray drying were amorphous up to 25 wt % drug, with loratadine remaining amorphous up to 50% drug. CCAB formulations with 10% drug proved effective at providing in vitro solubility enhancement for the crystalline flavonoid drug quercetin as well as ritonavir, but not for the more soluble APIs ibuprofen and clarithromycin and the more hydrophobic loratadine. CCAB did provide slow and controlled release of ibuprofen, offering a simple and promising Long-duration ibuprofen formulation. Formulation with clarithromycin showed the ability of the polymer to protect against degradation of the drug at stomach pH. Furthermore, CCAB ASDs with both loratadine and ibuprofen could be improved by the addition of the water-soluble polymer poly(vinylpyrrolidone) (PVP), with which CCAB shows good miscibility. CCAB provided solubility enhancement in some cases, and the slower drug release exhibited by CCAB, especially in the stomach, could be especially beneficial, for example, in formulations containing known stomach irritants like ibuprofen.


Asunto(s)
Celulosa , Ibuprofeno , Loratadina , Polímeros , Solubilidad , Polímeros/química , Celulosa/química , Celulosa/análogos & derivados , Ibuprofeno/química , Ibuprofeno/farmacocinética , Loratadina/química , Loratadina/análogos & derivados , Loratadina/farmacocinética , Liberación de Fármacos , Quercetina/química , Claritromicina/química , Ritonavir/química , Química Farmacéutica/métodos , Composición de Medicamentos/métodos
8.
Malar J ; 23(1): 159, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773528

RESUMEN

BACKGROUND: Primaquine (PQ) is the prototype 8-aminoquinoline drug, a class which targets gametocytes and hypnozoites. The World Health Organization (WHO) recommends adding a single low dose of primaquine to the standard artemisinin-based combination therapy (ACT) in order to block malaria transmission in regions with low malaria transmission. However, the haemolytic toxicity is a major adverse outcome of primaquine in glucose-6-phosphate dehydrogenase (G6PD)-deficient subjects. This study aimed to characterize the pharmacokinetic properties of primaquine and its major metabolites in G6PD-deficient subjects. METHODS: A single low-dose of primaquine (0.4-0.5 mg/kg) was administered in twenty-eight African males. Venous and capillary plasma were sampled up to 24 h after the drug administration. Haemoglobin levels were observed up to 28 days after drug administration. Only PQ, carboxy-primaquine (CPQ), and primaquine carbamoyl-glucuronide (PQCG) were present in plasma samples and measured using liquid chromatography mass spectrometry. Drug and metabolites' pharmacokinetic properties were investigated using nonlinear mixed-effects modelling. RESULTS: Population pharmacokinetic properties of PQ, CPQ, and PQCG can be described by one-compartment disposition kinetics with a transit-absorption model. Body weight was implemented as an allometric function on the clearance and volume parameters for all compounds. None of the covariates significantly affected the pharmacokinetic parameters. No significant correlations were detected between the exposures of the measured compounds and the change in haemoglobin or methaemoglobin levels. There was no significant haemoglobin drop in the G6PD-deficient patients after administration of a single low dose of PQ. CONCLUSIONS: A single low-dose of PQ was haematologically safe in this population of G6PD-normal and G6PD-deficient African males without malaria. Trial registration NCT02535767.


Asunto(s)
Antimaláricos , Deficiencia de Glucosafosfato Deshidrogenasa , Primaquina , Adolescente , Adulto , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Antimaláricos/farmacocinética , Antimaláricos/sangre , Antimaláricos/administración & dosificación , Primaquina/farmacocinética , Primaquina/sangre , Primaquina/administración & dosificación
9.
Endocr Pract ; 30(7): 616-623, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38692490

RESUMEN

OBJECTIVE: To evaluate the association of serum 25-hydroxyvitamin D (25(OH) D) levels with bone mineral density (BMD), fracture risk, and bone metabolism. METHODS: This multicenter cross-sectional study recruited menopausal females and males greater than or equal to 50 year old with osteoporosis/fractures between September 2016 and September 2021. Assessment included clinical data, 25(OH)D, intact parathyroid hormone (iPTH), procollagen type 1 amino-terminal propeptide (P1NP), carboxy-terminal collagen crosslinks (CTX), lateral thoracolumbar spine x-rays, and BMD. RESULTS: A total of 3003 individuals were stratified by 25(OH) D levels: 720 individuals (24%) <20 ng/mL, 1338 individuals (44.5%) 20 to 29 ng/mL, and 945 individuals (31.5%) ≥30 ng/mL. In unadjusted and multivariable models, BMD T-score, except spine, was significantly and positively associated with 25(OH)D levels. 25(OH) D levels were inversely associated with Fracture Risk Assessment Tool scores. Patients with 25(OH)D <20 ng/mL had significantly higher iPTH and bone turnover markers (P1NP and CTX) than patients with 25(OH)D â‰§20 ng/mL in all models. When analyzing bone-related markers and BMD, total hip and femoral neck BMD T-scores were positively correlated with 25(OH)D concentrations and BMI but negatively correlated with iPTH, P1NP, CTX, and age. In multivariate models with all bone-related markers, only 25(OH)D levels were significantly associated with total hip and femoral neck BMD. CONCLUSION: Vitamin D deficiency is significantly associated with decreased total hip and femoral neck BMD and increased fracture risk as assessed by Fracture Risk Assessment Tool. In those with osteoporosis/fractures, vitamin D is implicated in the causal relationship between bone remodeling and BMD. Assessing vitamin D status is imperative for those at risk for osteoporosis/fractures.


Asunto(s)
Densidad Ósea , Osteoporosis , Fracturas Osteoporóticas , Vitamina D , Humanos , Densidad Ósea/fisiología , Persona de Mediana Edad , Femenino , Vitamina D/análogos & derivados , Vitamina D/sangre , Masculino , Estudios Transversales , Anciano , Osteoporosis/sangre , Osteoporosis/epidemiología , Fracturas Osteoporóticas/sangre , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/etiología , Huesos/metabolismo , Hormona Paratiroidea/sangre , Remodelación Ósea/fisiología
10.
Arch Toxicol ; 98(8): 2677-2693, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38630283

RESUMEN

Cannabidiol (CBD), one of the major components extracted from the plant Cannabis sativa L., has been used as a prescription drug to treat seizures in many countries. CBD-induced male reproductive toxicity has been reported in animal models; however, the underlying mechanisms remain unclear. We previously reported that CBD induced apoptosis in primary human Leydig cells, which constitute the primary steroidogenic cell population in the testicular interstitium. In this study, we investigated the effects of CBD and its metabolites on TM3 mouse Leydig cells. CBD, at concentrations below 30 µM, reduced cell viability, induced G1 cell cycle arrest, and inhibited DNA synthesis. CBD induced apoptosis after exposure to high concentrations (≥ 50 µM) for 24 h or a low concentration (20 µM) for 6 days. 7-Hydroxy-CBD and 7-carboxy-CBD, the main CBD metabolites of CBD, exhibited the similar toxic effects as CBD. In addition, we conducted a time-course mRNA-sequencing analysis in both primary human Leydig cells and TM3 mouse Leydig cells to understand and compare the mechanisms underlying CBD-induced cytotoxicity. mRNA-sequencing analysis of CBD-treated human and mouse Leydig cells over a 5-day time-course indicated similar responses in both cell types. Mitochondria and lysosome dysfunction, oxidative stress, and autophagy were the major enriched pathways in both cell types. Taken together, these findings demonstrate comparable toxic effects and underlying mechanisms in CBD-treated mouse and primary human Leydig cells.


Asunto(s)
Apoptosis , Cannabidiol , Supervivencia Celular , Células Intersticiales del Testículo , Cannabidiol/toxicidad , Células Intersticiales del Testículo/efectos de los fármacos , Células Intersticiales del Testículo/metabolismo , Masculino , Animales , Humanos , Ratones , Supervivencia Celular/efectos de los fármacos , Apoptosis/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Línea Celular , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Células Cultivadas
11.
Int J Mol Sci ; 25(8)2024 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-38674124

RESUMEN

The measurement of blood glial fibrillary acidic protein (GFAP) and ubiquitin carboxy-terminal hydrolase L1 (UCH-L1) may assist in the management of mild traumatic brain injury (mTBI). This study aims to compare GFAP and UCH-L1 values measured using a handheld device with those measured using a core laboratory platform. We enrolled 230 mTBI patients at intermediate risk of complications. Following French guidelines, a negative S100B value permits the patient to be discharged without a computed tomography scan. Plasma GFAP and UCH-L1 levels were retrospectively measured using i-STAT® and Alinity® i analyzers in patients managed within 12 h post-trauma. Our analysis indicates a strong correlation of biomarker measurements between the two analyzers. Cohen's kappa coefficients and Lin's concordance coefficients were both ≥0.7, while Spearman's correlation coefficient was 0.94 for GFAP and 0.90 for UCH-L1. Additionally, the diagnostic performance in identifying an intracranial lesion was not significantly different between the two analyzers, with a sensitivity of 100% and specificity of approximately 30%. GFAP and UCH-L1 levels measured using Abbott's i-STAT® and Alinity® i platform assays are highly correlated both analytically and clinically in a cohort of 230 patients managed for mTBI according to French guidelines.


Asunto(s)
Biomarcadores , Proteína Ácida Fibrilar de la Glía , Ubiquitina Tiolesterasa , Humanos , Ubiquitina Tiolesterasa/sangre , Proteína Ácida Fibrilar de la Glía/sangre , Femenino , Masculino , Adulto , Persona de Mediana Edad , Inmunoensayo/métodos , Biomarcadores/sangre , Anciano , Conmoción Encefálica/sangre , Conmoción Encefálica/diagnóstico , Estudios Retrospectivos , Adulto Joven , Francia
12.
Calcif Tissue Int ; 112(2): 126-147, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35305134

RESUMEN

There exists a marked circadian variation for several bone markers (BM), which is influenced by endogenous as well as exogenous factors including hormones, physical activity, and fasting. Consequently, was the aim of this review to provide an overview of the knowledge of the circadian variation of BM and which factors influence this rhythmicity. A systematic search of PubMed was performed for studies evaluating the circadian variation of BM and which factors influence this rhythmicity. The studies were screened for eligibility by a set of predetermined criteria including a list of relevant BM and a minimum study duration of 24 h with at least 3 blood samples of which two should be at least 6 h apart. In total were 29 papers included. There exists a marked circadian variation for most BM including Carboxy-terminal Cross-Linked Telopeptide of Type I Collagen (CTX) and osteocalcin (OC) with nighttime or early morning peak. Pro-collagen Type I N-terminal Propeptide (PINP) and PTH also showed circadian rhythm but with less amplitude. The inter-osteoblast-osteoclast regulatory markers such as OPG, RANKL, FGF23, and sclerostin showed no circadian rhythm. The markers were differently affected by exogenous factors like fasting, which greatly reduced the circadian variation of CTX but did not affect PINP or OC. The marked circadian variation and the factors which influence the rhythmicity, e.g., fasting are of great consequence when measuring BM. To reduce variation and heighten validity should circadian variation and fasting be kept in mind when measuring BM.


Asunto(s)
Huesos , Ritmo Circadiano , Colágeno Tipo I , Biomarcadores , Osteocalcina
13.
Br J Clin Pharmacol ; 89(5): 1672-1681, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36517987

RESUMEN

AIMS: Cyclosporin A (CyA) has potent inhibitory activity on organic anion transporting polypeptide 1B (OATP1B), causing drug-drug interactions with its substrate drugs. 3-carboxy-4-methyl-5-propyl-2-furanpropionate (CMPF), a uraemic toxin, has also been suggested to inhibit OATP1B activity. Recent study has identified coproporphyrin-I (CP-I) as a specific endogenous substrate for OATP1B, which is useful to indicate OATP1B activity. We investigated the relationship of CP-I with CyA and CMPF concentrations in patients taking CyA. METHODS: In total, 121 blood samples from 74 patients who took CyA and underwent routine therapeutic drug monitoring were divided into trough and peak samples. RESULTS: CyA and CP-I concentrations were significantly higher in peak samples than in trough samples. A positive correlation between CP-I and CyA concentrations was found in all samples and in trough and peak samples, while no correlation was observed between CP-I and CMPF concentrations. Multiple regression analysis identified CyA and C-reactive protein concentrations as independent factors affecting CP-I concentration, with blood CyA concentration having markedly greater contribution to plasma CP-I concentration. CONCLUSION: The present study suggests that CyA inhibits OATP1B activity in a concentration-dependent manner in clinical setting, and that dose adjustment of OATP1B substrate drugs coadministered with CyA according to plasma CMPF concentration may not be necessary.


Asunto(s)
Transportadores de Anión Orgánico , Humanos , Transportadores de Anión Orgánico/metabolismo , Ciclosporina , Coproporfirinas/metabolismo , Coproporfirinas/farmacología , Transportador 1 de Anión Orgánico Específico del Hígado , Biomarcadores
14.
J Fluoresc ; 33(1): 209-221, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36399249

RESUMEN

In the present study, we have successfully synthesized and characterized carboxy methyl cashew gum modified gold nanoparticles (CMCG-AuNPs) via a microwave-assisted method and used as a calorimetric probe for selective detection of Hg2+ ions as well as catalytic reduction of methyl red in an aqueous medium. The effect of different parameters including concentration and irradiation time on the formation of CMCG-AuNPs was also investigated. The presence of strong surface plasmon resonance (SPR) peak in the visible region indicated the formation of AuNPs. The characterization techniques were identified the interaction between the CMCG and AuNPs with estimation of size and morphology. The face centred cubic (FCC) crystal structure was identified by using XRD and supporting with SAED pattern. TEM images of CMCG-AuNPs were exhibited as polydispersed with spherical in shape and the average particle size was 12 ± 3 nm. The synthesized CMCG-AuNPs were utilized to sensing Hg2+ ions in an aqueous medium, the presence of Hg2+ ions selectively among other metal ions, the CMCG-AuNPs were aggregated by changing the color from wine red to purple blue accompanied by change in the position of SPR peak and intensity. It was observed as a strong linear relationship based on the change in intensity, the limit of detection was determined to be 0.277 nM. The catalytic activity was also examined for the reduction of methyl red (MR) in the presence of CMCG-AuNPs was completed within 12 min and followed pseudo-first order kinetics with a rate constant of 0.261 min-1. From the obtained results, the synthesized CMCG-AuNPs were useful for detection of heavy metal ions as well as toxic pollutants degradation via a green method, and utilized sensing, environmental, and biomedical application in future.

15.
J Fluoresc ; 33(6): 2257-2272, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37014521

RESUMEN

Humans are exposed to excessive nanoplastics (NPs) which have ample affinity for globular proteins. We investigated the interaction of functionalized polystyrene nanoplastics (plain: PS, carboxy: PS-COOH, and amine: PS-NH2) with human hemoglobin (Hb) utilizing multi-spectroscopic and docking approaches to acquire insights into molecular aspects of binding mechanism, which will be helpful in assessing the toxicokinetics or toxicodynamics of nanoplastics NPs. Hypsochromicity and hypochromicity were observed invariably in all the spectra (steady-state fluorescence emission, synchronous and three-dimensional) for all complexes, among which PS-NH2 binds effectively and changes the Hb's conformation by enhancing hydrophobicity around aromatic residues, notably tryptophan. All the NPs bind with the hydrophobic pocket of B-chain in Hb, where PS and PS-NH2 bind via hydrophobic force while PS-COOH binds via hydrogen bonding (predominantly) and van der Waals force, consistent validated with docking results. The minimal shift in absorbance peak also indicates enhanced hydrophobicity by PS-NH2 with larger aggregation as demonstrated in resonance light scattering. The amide band's shift, secondary structural analysis, and presence of characteristic functional group peaks in complexes in Infra-Red spectra confirm the structural changes in the protein. As seen in field emission scanning microscopy images, NPs penetrate the surface of proteins. These findings conclude that polystyrene NPs interact with Hb, causing structural alterations that may affect functional characteristics as well, with the greatest effect being in the order: PS-NH2>PS-COOH>PS.


Asunto(s)
Nanopartículas , Contaminantes Químicos del Agua , Humanos , Poliestirenos/química , Microplásticos , Nanopartículas/química , Contaminantes Químicos del Agua/química , Hemoglobinas
16.
Arch Toxicol ; 97(12): 3227-3241, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37794255

RESUMEN

Cannabidiol (CBD) is one of the most prevalent and abundant cannabinoids extracted from the plant Cannabis sativa. CBD has been reported to induce male reproductive toxicity in animal models. In this study, we examined the effects of CBD and its main metabolites, 7-carboxy-CBD and 7-hydroxy-CBD, on primary human Leydig cells, which play a crucial role in male reproductive health. Our results showed that CBD, at concentrations below the Bayesian benchmark dose (BMD)50, inhibited the growth of human Leydig cells by arresting the cell cycle at G1/S transition, disrupting cell cycle regulators, and decreasing DNA synthesis. Concentration-response transcriptomic profiling identified that apoptosis was one of the top biological processes significantly affected by treatment with CBD for 24 h. The occurrence of apoptosis was confirmed by increased activation of caspase-3/7 and an increased proportion of annexin V and propidium iodide (PI)-positive cells. Similar to CBD, both 7-carboxy-CBD and 7-hydroxy-CBD decreased cell viability and induced apoptosis after treatment for 24 h. 7-Hydroxy-CBD and 7-carboxy-CBD showed lower cytotoxicity than CBD, and 7-carboxy-CBD had the lowest cytotoxicity among the three compounds. Our findings revealed that CBD and its main metabolites can cause adverse effects on primary human Leydig cells.


Asunto(s)
Cannabidiol , Cannabinoides , Masculino , Animales , Humanos , Cannabidiol/toxicidad , Teorema de Bayes , Células Intersticiales del Testículo , Apoptosis
17.
Eur Heart J Suppl ; 25(Suppl C): C306-C308, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37125305

RESUMEN

Iron is an essential micronutrient for several physiological processes in the body beyond erythropoiesis. Iron deficiency (ID) is a common comorbidity observed in about 50% of patients with stable heart failure (HF) irrespective of the left ventricular function. The presence of ID is often as a multi-factorial condition, and it is associated with exercise intolerance, reduced quality of life, increased hospitalization rate, and mortality risk regardless of anaemia. The intravenous administration of iron to correct ID has emerged as a promising treatment in HF with reduced ejection fraction as it has been shown to alleviate symptoms, improve quality of life and exercise capacity, and reduce hospitalizations.

18.
Int J Mol Sci ; 24(5)2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36901717

RESUMEN

The most common primary liver cancer is hepatocellular carcinoma (HCC), and its mortality rate is increasing globally. The overall 5-year survival of patients with liver cancer is currently 10-20%. Moreover, because early diagnosis can significantly improve prognosis, which is highly correlated with tumor stage, early detection of HCC is critical. International guidelines advise using α-FP biomarker with/without ultrasonography for HCC surveillance in patients with advanced liver disease. However, traditional biomarkers are sub-optimal for risk stratification of HCC development in high-risk populations, early diagnosis, prognostication, and treatment response prediction. Since about 20% of HCCs do not produce α-FP due to its biological diversity, combining α-FP with novel biomarkers can enhance HCC detection sensitivity. There is a chance to offer promising cancer management methods in high-risk populations by utilizing HCC screening strategies derived from new tumor biomarkers and prognostic scores created by combining biomarkers with distinct clinical parameters. Despite numerous efforts to identify molecules as potential biomarkers, there is no single ideal marker in HCC. When combined with other clinical parameters, the detection of some biomarkers has higher sensitivity and specificity in comparison with a single biomarker. Therefore, newer biomarkers and models, such as the Lens culinaris agglutinin-reactive fraction of Alpha-fetoprotein (α-FP), α-FP-L3, Des-γ-carboxy-prothrombin (DCP or PIVKA-II), and the GALAD score, are being used more frequently in the diagnosis and prognosis of HCC. Notably, the GALAD algorithm was effective in HCC prevention, particularly for cirrhotic patients, regardless of the cause of their liver disease. Although the role of these biomarkers in surveillance is still being researched, they may provide a more practical alternative to traditional imaging-based surveillance. Finally, looking for new diagnostic/surveillance tools may help improve patients' survival. This review discusses the current roles of the most used biomarkers and prognostic scores that may aid in the clinical management of HCC patients.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Detección Precoz del Cáncer , Biomarcadores , Biomarcadores de Tumor , alfa-Fetoproteínas , Sensibilidad y Especificidad , Protrombina , Algoritmos
19.
Int J Mol Sci ; 24(24)2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38139093

RESUMEN

The multifunctionality of an A3B mixed-substituted porphyrin, namely 5-(4-carboxyphenyl)-10,15,20-tris(4-methylphenyl)porphyrin (5-COOH-3MPP), was proven due to its capacity to detect procaine by different methods, depending on the polymer matrix in which it is incorporated. The hybrid nanomaterial containing k-carrageenan and AuNPs (5-COOH-3MPP-k-carrageenan-AuNPs) was able to optically detect procaine in the concentration range from 5.76 × 10-6 M to 2.75 × 10-7 M, with a limit of detection (LOD) of 1.33 × 10-7 M. This method for the detection of procaine gave complementary results to the potentiometric one, which uses 5-COOH-3MPP as an electroactive material incorporated in a polyvinylchloride (PVC) membrane plasticized with o-NPOE. The detected concentration range by this ion-selective membrane electrode is wider (enlarged in the field of higher concentrations from 10-2 to 10-6 M), linearly dependent with a 53.88 mV/decade slope, possesses a detection limit of 7 × 10-7 M, a response time of 60 s, and has a certified stability for a working period of six weeks.


Asunto(s)
Nanopartículas del Metal , Porfirinas , Procaína , Carragenina , Oro , Electrodos de Iones Selectos
20.
Int J Mol Sci ; 24(21)2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37958792

RESUMEN

In this review, the structure, isoform, and physiological role of the carboxy-terminal PDZ ligand of neuronal nitric oxide synthase (CAPON) are summarized. There are three isoforms of CAPON in humans, including long CAPON protein (CAPON-L), short CAPON protein (CAPON-S), and CAPON-S' protein. CAPON-L includes three functional regions: a C-terminal PDZ-binding motif, carboxypeptidase (CPE)-binding region, and N-terminal phosphotyrosine (PTB) structural domain. Both CAPON-S and CAPON-S' only contain the C-terminal PDZ-binding motif. The C-terminal PDZ-binding motif of CAPON can bind with neuronal nitric oxide synthase (nNOS) and participates in regulating NO production and neuronal development. An overview is given on the relationship between CAPON and heart diseases, diabetes, psychiatric disorders, and tumors. This review will clarify future research directions on the signal pathways related to CAPON, which will be helpful for studying the regulatory mechanism of CAPON. CAPON may be used as a drug target, which will provide new ideas and solutions for treating human diseases.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Transducción de Señal , Humanos , Óxido Nítrico Sintasa de Tipo I/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo
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