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1.
Cell Mol Life Sci ; 81(1): 205, 2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38703204

RESUMEN

BACKGROUND: Exposure to chronic psychological stress (CPS) is a risk factor for thrombotic cardiocerebrovascular diseases (CCVDs). The expression and activity of the cysteine cathepsin K (CTSK) are upregulated in stressed cardiovascular tissues, and we investigated whether CTSK is involved in chronic stress-related thrombosis, focusing on stress serum-induced endothelial apoptosis. METHODS AND RESULTS: Eight-week-old wild-type male mice (CTSK+/+) randomly divided to non-stress and 3-week restraint stress groups received a left carotid artery iron chloride3 (FeCl3)-induced thrombosis injury for biological and morphological evaluations at specific timepoints. On day 21 post-stress/injury, the stress had enhanced the arterial thrombi weights and lengths, in addition to harmful alterations of plasma ADAMTS13, von Willebrand factor, and plasminogen activation inhibitor-1, plus injured-artery endothelial loss and CTSK protein/mRNA expression. The stressed CTSK+/+ mice had increased levels of injured arterial cleaved Notch1, Hes1, cleaved caspase8, matrix metalloproteinase-9/-2, angiotensin type 1 receptor, galactin3, p16IN4A, p22phox, gp91phox, intracellular adhesion molecule-1, TNF-α, MCP-1, and TLR-4 proteins and/or genes. Pharmacological and genetic inhibitions of CTSK ameliorated the stress-induced thrombus formation and the observed molecular and morphological changes. In cultured HUVECs, CTSK overexpression and silencing respectively increased and mitigated stressed-serum- and H2O2-induced apoptosis associated with apoptosis-related protein changes. Recombinant human CTSK degraded γ-secretase substrate in a dose-dependent manor and activated Notch1 and Hes1 expression upregulation. CONCLUSIONS: CTSK appeared to contribute to stress-related thrombosis in mice subjected to FeCl3 stress, possibly via the modulation of vascular inflammation, oxidative production and apoptosis, suggesting that CTSK could be an effective therapeutic target for CPS-related thrombotic events in patients with CCVDs.


Asunto(s)
Apoptosis , Catepsina K , Cloruros , Modelos Animales de Enfermedad , Compuestos Férricos , Trombosis , Animales , Humanos , Masculino , Ratones , Proteína ADAMTS13/metabolismo , Proteína ADAMTS13/genética , Catepsina K/metabolismo , Catepsina K/genética , Cloruros/metabolismo , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Inhibidor 1 de Activador Plasminogénico/metabolismo , Inhibidor 1 de Activador Plasminogénico/genética , Estrés Psicológico/complicaciones , Estrés Psicológico/metabolismo , Trombosis/metabolismo , Trombosis/patología , Factor de Transcripción HES-1/metabolismo , Factor de Transcripción HES-1/genética
2.
Int J Mol Sci ; 25(8)2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38673775

RESUMEN

Solute carrier family 26 member 4 (SLC26A4) is a member of the SLC26A transporter family and is expressed in various tissues, including the airway epithelium, kidney, thyroid, and tumors. It transports various ions, including bicarbonate, chloride, iodine, and oxalate. As a multiple-ion transporter, SLC26A4 is involved in the maintenance of hearing function, renal function, blood pressure, and hormone and pH regulation. In this review, we have summarized the various functions of SLC26A4 in multiple tissues and organs. Moreover, the relationships between SLC26A4 and other channels, such as cystic fibrosis transmembrane conductance regulator, epithelial sodium channel, and sodium chloride cotransporter, are highlighted. Although the modulation of SLC26A4 is critical for recovery from malfunctions of various organs, development of specific inducers or agonists of SLC26A4 remains challenging. This review contributes to providing a better understanding of the role of SLC26A4 and development of therapeutic approaches for the SLC26A4-associated hearing loss and SLC26A4-related dysfunction of various organs.


Asunto(s)
Transportadores de Sulfato , Humanos , Transportadores de Sulfato/metabolismo , Transportadores de Sulfato/genética , Animales , Riñón/metabolismo , Antiportadores de Cloruro-Bicarbonato/metabolismo , Antiportadores de Cloruro-Bicarbonato/genética , Especificidad de Órganos , Cloruros/metabolismo , Transporte Iónico
3.
Water Res ; 256: 121539, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38583335

RESUMEN

Inorganic coagulants such as poly aluminum ferric chloride (Al/Fe) are applied conventionally to sewage sludge dewatering and can be retained in the sludge cake, causing its conductivity to increase and generate secondary pollution. To reduce these disadvantages, there is a need to develop alternative, more sustainable chemicals as substitutes for conventional inorganic coagulants. In the present investigation, the application of a polymeric chitosan quaternary ammonium salt (CQAS) is explored as a complete, or partial, replacement for Al/Fe in the context of sludge dewatering processes. Laboratory experiments using digested sewage sludge showed that CQAS could effectively substitute for over 80 % of the Al/Fe inorganic coagulant in the sludge dewatering process. This substitution resulted in a reduction of sludge cake conductivity by more than 50 %. Simulation of sludge dewatering curves and imaging of the sludge surface indicated that the addition of CQAS led to an increase in nanosized pores, and a decrease in the specific resistance of the sludge filter cake as the dosage of Al/Fe decreased to around 30 %. The variations of fluorescence emission, quantum yield and carboxylic and amino groups, suggested that the chelating of Al/Fe decreased due to the bridging effects of CQAS. The CQAS had different flocculation bridging effects on various EPS fractions, which varied the amount of protein chelated with Al/Fe in each fraction. This study provides new information about the benefits of replacing conventional inorganic coagulants with natural organic polymers for sewage sludge dewatering, in terms of reduced sludge cake conductivity and greater dry solids content.


Asunto(s)
Quitosano , Compuestos Férricos , Aguas del Alcantarillado , Aguas del Alcantarillado/química , Quitosano/química , Compuestos Férricos/química , Compuestos de Amonio Cuaternario/química , Floculación , Cloruros/química , Eliminación de Residuos Líquidos/métodos , Aluminio/química
4.
Chemistry ; 30(31): e202304375, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38563634

RESUMEN

The clinical translation of polysarcosine (pSar) as polyethylene glycol (PEG) replacement in the development of novel nanomedicines creates a broad demand of polymeric material in high-quality making high-purity sarcosine N-carboxyanhydride (Sar-NCA) as monomer for its production inevitable. Within this report, we present the use of triethyloxonium tetrafluoroborate in Sar-NCA synthesis with focus on amino acid and chloride impurities to avoid the sublimation of Sar-NCAs. With a view towards upscaling into kilogram or ton scale, a new methodology of monomer purification is introduced by utilizing the Meerwein's Salt triethyloxonium tetrafluoroborate to remove chloride impurities by covalent binding and converting chloride ions into volatile products within a single step. The novel straightforward technique enables access to monomers with significantly reduced chloride content (<100 ppm) compared to Sar-NCA derived by synthesis or sublimation. The derived monomers enable the controlled-living polymerization in DMF and provide access to pSar polymers with Poisson-like molecular weight distribution within a high range of chain lengths (Xn 25-200). In conclusion, the reported method can be easily applied to Sar-NCA synthesis or purification of commercially available pSar-NCAs and eases access to well-defined hetero-telechelic pSar polymers.


Asunto(s)
Cloruros , Polimerizacion , Sarcosina , Sarcosina/química , Sarcosina/análogos & derivados , Cloruros/química , Polietilenglicoles/química , Polímeros/química , Boratos/química , Anhídridos/química , Péptidos
5.
Talanta ; 273: 125899, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38484502

RESUMEN

Sensing and characterizing water-soluble polypeptides are essential in various biological applications. However, detecting polypeptides using Surface-Enhanced Raman Scattering (SERS) remains a challenge due to the dominance of aromatic amino acid residues and backbones in the signal, which hinders the detection of non-aromatic amino acid residues. Herein, intra-nanoparticle plasmonic nanogap were designed by etching the Ag shell in Au@AgNPs (i.e., obtaining AuAg cores) with chlorauric acid under mild conditions, at the same time forming the outermost Au shell and the void between the AuAg cores and the Au shell (AuAg@void@Au). By varying the Ag to added chloroauric acid molar ratios, we pioneered a simple, controllable, and general synthetic strategy to form interlayer-free nanoparticles with tunable Au shell thickness, achieving precise regulation of electric field enhancement within the intra-nanogap. As validation, two polypeptide molecules, bacitracin and insulin B, were successfully synchronously encapsulated and spatial-confined in the intra-nanogap for sensing. Compared with concentrated 50 nm AuNPs and Au@AgNPs as SERS substrates, our simultaneous detection method improved the sensitivity of the assay while benefiting to obtain more comprehensive characteristic peaks of polypeptides. The synthetic strategy of confining analytes while fabricating plasmonic nanostructures enables the diffusion of target molecules into the nanogap in a highly specific and sensitive manner, providing the majority of the functionality required to achieve peptide detection or sequencing without the hassle of labeling.


Asunto(s)
Cloruros , Compuestos de Oro , Nanopartículas del Metal , Nanoestructuras , Nanopartículas del Metal/química , Oro/química , Nanoestructuras/química , Espectrometría Raman/métodos
6.
Inflammopharmacology ; 32(2): 1371-1386, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38448794

RESUMEN

Alzheimer's disease (AD) is a neurodegenerative disorder that impairs mental ability and interrupts cognitive function. Heavy metal exposure like aluminum chloride is associated with neurotoxicity linked to neuro-inflammation, oxidative stress, accumulation of amyloid plaques, phosphorylation of tau proteins associated with AD like symptoms. The objective of the present investigation was to assess the effect 3-acetyl coumarin (3AC) in a rat model of AD. Preliminary screening was performed with SWISS ADME to check for the bioavailability of 3-AC and likeness score which proved favorable. 3-AC docked against Caspase 3, NF-κß and tau protein kinase I exhibited good binding energies. Male rats were divided into six groups (n = 5). AlCl3 (100 mg/kg BW) was administered for 28 days before starting treatment to induce AD. Normal control rats received vehicle. Treatment groups received 10, 20 and 30 mg/kg 3-AC for 28 days. Rivastigmine (2 mg/kg) was the standard. Behavioral tests (EPM, MWM) were performed at 7-day intervals throughout study period. Rats showed improved spatial memory and learning in treatment groups during behavioral tests. Rats were euthanized on day 28. Inflammatory markers (IL-1ß, IL-16 and TNFα) exhibited significant improvement (p < 0.001) in treated rats. Oxidative stress enzymes (SOD, CAT, GSH, MDA) were restored. Caspase3 and NF-κß quantified through qRT-PCR also decreased significantly (p < 0.001) when compared to disease control group. Levels of acetyl cholinesterase, dopamine and noradrenaline were also restored in treated rats significantly (p < 0.001). 3-AC treatment restored neuroprotection probably because of anti-inflammatory, anti-oxidant and anti-cholinesterase potential; hence, this can be considered a promising therapeutic potential alternative.


Asunto(s)
Enfermedad de Alzheimer , Fármacos Neuroprotectores , Ratas , Masculino , Animales , Cloruro de Aluminio/efectos adversos , Enfermedad de Alzheimer/inducido químicamente , Enfermedad de Alzheimer/tratamiento farmacológico , Compuestos de Aluminio/uso terapéutico , Compuestos de Aluminio/toxicidad , Cloruros/toxicidad , Cloruros/uso terapéutico , Ratas Wistar , Estrés Oxidativo , Antioxidantes/farmacología , Inflamación/tratamiento farmacológico , Inflamación/complicaciones , Cumarinas/farmacología , Cumarinas/uso terapéutico , Modelos Animales de Enfermedad
7.
eNeuro ; 11(3)2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38471777

RESUMEN

Synchronization in the gamma band (25-150 Hz) is mediated by PV+ inhibitory interneurons, and evidence is accumulating for the essential role of gamma oscillations in cognition. Oscillations can arise in inhibitory networks via synaptic interactions between individual oscillatory neurons (mean-driven) or via strong recurrent inhibition that destabilizes the stationary background firing rate in the fluctuation-driven balanced state, causing an oscillation in the population firing rate. Previous theoretical work focused on model neurons with Hodgkin's Type 1 excitability (integrators) connected by current-based synapses. Here we show that networks comprised of simple Type 2 oscillators (resonators) exhibit a supercritical Hopf bifurcation between synchrony and asynchrony and a gradual transition via cycle skipping from coupled oscillators to stochastic population oscillator (SPO), as previously shown for Type 1. We extended our analysis to homogeneous networks with conductance rather than current based synapses and found that networks with hyperpolarizing inhibitory synapses were more robust to noise than those with shunting synapses, both in the coupled oscillator and SPO regime. Assuming that reversal potentials are uniformly distributed between shunting and hyperpolarized values, as observed in one experimental study, converting synapses to purely hyperpolarizing favored synchrony in all cases, whereas conversion to purely shunting synapses made synchrony less robust except at very high conductance strengths. In mature neurons the synaptic reversal potential is controlled by chloride cotransporters that control the intracellular concentrations of chloride and bicarbonate ions, suggesting these transporters as a potential therapeutic target to enhance gamma synchrony and cognition.


Asunto(s)
Cloruros , Transmisión Sináptica , Transmisión Sináptica/fisiología , Simulación por Computador , Interneuronas/fisiología , Sinapsis/fisiología , Potenciales de Acción/fisiología , Modelos Neurológicos
8.
Methods Mol Biol ; 2791: 35-43, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38532090

RESUMEN

The study of the localization of secondary metabolites in both plants and the cell cultures on the intravital sections is hampered by the difficulty of obtaining thin, correctly oriented sections. Techniques for fixing tissues in resins allow these difficulties to be overcome. Properly selected tissue fixation techniques allow using different dyes to identify the compound of interest. In addition, some components of tissue fixation can act as fixatives and as a dye for identifying secondary metabolites. For example, osmium tetroxide, which fixes lipids in tissues, stains phenolic compounds black. This paper describes methods for the detection of phenolic compounds in morphogenic callus culture of buckwheat using osmium tetroxide, Toluidine Blue O dye, and ferric chloride as dyes in epoxy resin-embedded cell culture with double fixation of the material and when material fixed in Karnovsky's fixative.


Asunto(s)
Colorantes , Fagopyrum , Compuestos Férricos , Tetróxido de Osmio , Cloruros , Cloruro de Tolonio , Fijadores , Fijación del Tejido , Técnicas de Cultivo de Célula , Hierro , Osmio
9.
Support Care Cancer ; 32(4): 256, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38546900

RESUMEN

BACKGROUND: For patients with nasopharyngeal carcinoma (NPC), the incidence of malnutrition is quite high, and malnutrition has severe effects on NPC patients. However, there is currently no recognized gold standard or specific nutritional assessment tool available to assess malnutrition in NPC patients. Our objective was to develop and verify a new nomogram model for NPC patients. METHODS: Data were collected from NPC patients. To evaluate risk factors for malnutrition, univariate and multivariate logistic regression analyses were used. Based on the risk factors, a new nomogram model was developed. The efficacy of the model was evaluated and validated. RESULTS: Logistic regression analysis showed that age ≥ 65 years, the number of chemotherapy cycles completed ≥ 1, a high total radiation dose received, low body mass index (BMI), low albumin, and low chloride were the risk factors. The assessment effect of the new model was good by evaluation and validation; it can be used as an assessment tool for malnutrition in NPC patients. CONCLUSIONS: Age ≥ 65 years, completing ≥ 1 chemotherapy cycles, a high total radiation dose received, low BMI, low albumin, and low chloride levels are risk factors for malnutrition in NPC patients. The assessment effect of the new model, developed based on these risk factors, is good, and it can be used as an assessment tool for malnutrition in NPC patients.


Asunto(s)
Desnutrición , Neoplasias Nasofaríngeas , Humanos , Anciano , Carcinoma Nasofaríngeo/patología , Nomogramas , Neoplasias Nasofaríngeas/radioterapia , Cloruros/uso terapéutico , Factores de Riesgo , Desnutrición/epidemiología , Desnutrición/etiología , Albúminas
10.
Sci Total Environ ; 926: 172046, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38552983

RESUMEN

Cadmium (Cd) contamination in rice ecosystems posed a critical challenge to global food security and environmental health. This study aimed to unveil the key mechanisms trough hydroponic experiments by which chloride (Cl-) promoted the absorption and accumulation of cadmium (Cd) in rice plants. The findings elucidated that the addition of Cl- increased Cd uptake by rice roots (5.1 % âˆ¼ 61 %), acting both directly by enhancing root morphology and indirectly through regulating of the main transporter genes of Cd. The study unveiled that Cl- addition significantly improves Cd bioavailability in roots, which was discernible through the augmentation of Cd concentration and proportion in subcellular fractions, coupled with elevated energy values in key cellular components. Moreover, Cl- addition further augmented the intricate process of Cd transport from roots to shoots (16.1- 86.7 %), which was mainly attributed to the underexpression of OsHMA3 and the decrease in the formation of sulfuhydryl substances. This research provides a comprehensive understanding of the complex mechanisms governing Cd dynamics in rice plants in the presence of Cl-. By elucidating these processes, our findings not only contribute to fundamental knowledge in plant metal uptake but also hold promising implications for mitigating Cd contamination in rice cultivation systems.


Asunto(s)
Oryza , Contaminantes del Suelo , Cadmio , Oryza/fisiología , Cloruros , Ecosistema , Transporte Biológico , Raíces de Plantas
11.
J Inorg Biochem ; 255: 112541, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38554578

RESUMEN

Our prior studies have illustrated that the uracil ruthenium(II) diimino complex, [Ru(H3ucp)Cl(PPh3)] (1) (H4ucp = 2,6-bis-((6-amino-1,3-dimethyluracilimino)methylene)pyridine) displayed high hypoglycemic effects in diet-induced diabetic rats. To rationalize the anti-diabetic effects of 1, three new derivatives have been prepared, cis-[Ru(bpy)2(urdp)]Cl2 (2) (urdp = 2,6-bis-((uracilimino)methylene)pyridine), trans-[RuCl2(PPh3)(urdp)] (3), and cis-[Ru(bpy)2(H4ucp)](PF6)2 (4). Various physicochemical techniques were utilized to characterize the structures of the novel ruthenium compounds. Prior to biomolecular interactions or in vitro studies, the stabilities of 1-4 were monitored in anhydrous DMSO, aqueous phosphate buffer containing 2% DMSO, and dichloromethane (DCM) via UV-Vis spectrophotometry. Time-dependent stability studies showed ligand exchange between DMSO nucleophiles and chloride co-ligands of 1 and 3, which was suppressed in the presence of an excess amount of chloride ions. In addition, the metal complexes 1 and 3 are stable in both DCM and an aqueous phosphate buffer containing 2% DMSO. In the case of compounds 2 and 4 with no chloride co-ligands within their coordination spheres, high stability in aqueous phosphate buffer containing 2% DMSO was observed. Fluorescence emission titrations of the individual ruthenium compounds with bovine serum albumin (BSA) showed that the metal compounds interact non-discriminately within the protein's hydrophobic cavities as moderate to strong binders. The metal complexes were capable of disintegrating mature amylin amyloid fibrils. In vivo glucose metabolism studies in liver (Chang) cell lines confirmed enhanced glucose metabolism as evidenced by the increased glucose utilization and glycogen synthesis in liver cell lines in the presence of complexes 2-4.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Diabetes Mellitus Experimental , Rutenio , Ratas , Animales , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Albúmina Sérica Bovina/química , Rutenio/química , Dimetilsulfóxido , Hipoglucemiantes/farmacología , Cloruros , Diabetes Mellitus Experimental/tratamiento farmacológico , Piridinas/química , Péptidos , Compuestos de Rutenio , Glucosa , Fosfatos , Antineoplásicos/farmacología , Ligandos
12.
Kidney360 ; 5(3): 471-480, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38433340

RESUMEN

Pictured, described, and speculated on, for close to 400 years, the function of the rectal gland of elasmobranchs remained unknown. In the late 1950s, Burger discovered that the rectal gland of Squalus acanthias secreted an almost pure solution of sodium chloride, isosmotic with blood, which could be stimulated by volume expansion of the fish. Twenty five years later, Stoff discovered that the secretion of the gland was mediated by adenyl cyclase. Studies since then have shown that vasoactive intestinal peptide (VIP) is the neurotransmitter responsible for activating adenyl cyclase; however, the amount of circulating VIP does not change in response to volume expansion. The humoral factor involved in activating the secretion of the gland is C-type natriuretic peptide, secreted from the heart in response to volume expansion. C-type natriuretic peptide circulates to the gland where it stimulates the release of VIP from nerves within the gland, but it also has a direct effect, independent of VIP. Sodium, potassium, and chloride are required for the gland to secrete, and the secretion of the gland is inhibited by ouabain or furosemide. The current model for the secretion of chloride was developed from this information. Basolateral NaKATPase maintains a low intracellular concentration of sodium, which establishes the large electrochemical gradient for sodium directed into the cell. Sodium moves from the blood into the cell (together with potassium and chloride) down this electrochemical gradient, through a coupled sodium, potassium, and two chloride cotransporter (NKCC1). On activation, chloride moves from the cell into the gland lumen, down its electrical gradient through apical cystic fibrosis transmembrane regulator. The fall in intracellular chloride leads to the phosphorylation and activation of NKCC1 that allows more chloride into the cell. Transepithelial sodium secretion into the lumen is driven by an electrical gradient through a paracellular pathway. The aim of this review was to examine the history of the origin of this model for the transport of chloride and suggest that it is applicable to many epithelia that transport chloride, both in resorptive and secretory directions.


Asunto(s)
Tiburones , Animales , Tiburones/metabolismo , Glándula de Sal/metabolismo , Cloruros/metabolismo , Cloruros/farmacología , Cazón/metabolismo , Adenilil Ciclasas/metabolismo , Adenilil Ciclasas/farmacología , Péptido Natriurético Tipo-C/metabolismo , Péptido Natriurético Tipo-C/farmacología , Péptido Intestinal Vasoactivo/metabolismo , Péptido Intestinal Vasoactivo/farmacología , Sodio/metabolismo , Sodio/farmacología , Potasio/metabolismo , Potasio/farmacología
13.
Water Res ; 254: 121440, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38479170

RESUMEN

The ultraviolet/monochloramine (UV/NH2Cl) process is an emerging advanced oxidation process with promising prospects in water treatment. Previous studies developed kinetic models of UV/NH2Cl for simulating radical concentrations and pollutant degradation. However, the reaction rate constants of Cl2•- with bicarbonate and carbonate (kCl2•-, HCO3- and kCl2•-, CO32-) were overestimated in literature. Consequently, when dosing 1 mM chloride and 1 mM bicarbonate, the current models of UV/NH2Cl severely under-predicted the experimental concentrations of three important radicals (i.e., hydroxyl radical (HO•), chlorine radical (Cl•), and dichloride radical (Cl2•-)) with great deviations (> 90 %). To investigate this issue, the transformation reactions among these three radicals in UV/NH2Cl were systematically studied. For the first time, it was found that in addition to Cl•, Cl2•- was also an important parent radical of HO• in the presence of chloride, and chloride could effectively compensate the inhibitory effect of bicarbonate on HO• generation in the system. Moreover, reactions and rate constants in current models were scrutinized from corresponding literature, and the reaction rate constants of Cl2•- with bicarbonate and carbonate (kCl2•-, HCO3- and kCl2•-, CO32-) were reevaluated to be 1.47 × 105 and 3.78 × 106 M-1s-1, respectively, by laser flash photolysis. With the newly obtained rate constants, the refined model could accurately simulate concentrations of all three radicals under different chloride and bicarbonate dosages with satisfactory deviations (< 30 %). Meanwhile, the refined model performed much better in predicting pollutant degradation and radical contribution compared with the unrefined model (with the previously estimated kCl2•-, HCO3- and kCl2•-, CO32-). The results of this study enhanced the accuracy and applicability of the kinetic model of UV/NH2Cl, and deepened the understanding of radical transformation in the process.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Bicarbonatos , Cloruros , Rayos Ultravioleta , Contaminantes Químicos del Agua/análisis , Cloro , Carbonatos , Cinética , Oxidación-Reducción
14.
Sci Transl Med ; 16(739): eadk9109, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38507469

RESUMEN

Myasthenia gravis (MG) is a neuromuscular disease that results in compromised transmission of electrical signals at the neuromuscular junction (NMJ) from motor neurons to skeletal muscle fibers. As a result, patients with MG have reduced skeletal muscle function and present with symptoms of severe muscle weakness and fatigue. ClC-1 is a skeletal muscle specific chloride (Cl-) ion channel that plays important roles in regulating neuromuscular transmission and muscle fiber excitability during intense exercise. Here, we show that partial inhibition of ClC-1 with an orally bioavailable small molecule (NMD670) can restore muscle function in rat models of MG and in patients with MG. In severely affected MG rats, ClC-1 inhibition enhanced neuromuscular transmission, restored muscle function, and improved mobility after both single and prolonged administrations of NMD670. On this basis, NMD670 was progressed through nonclinical safety pharmacology and toxicology studies, leading to approval for testing in clinical studies. After successfully completing phase 1 single ascending dose in healthy volunteers, NMD670 was tested in patients with MG in a randomized, placebo-controlled, single-dose, three-way crossover clinical trial. The clinical trial evaluated safety, pharmacokinetics, and pharmacodynamics of NMD670 in 12 patients with mild MG. NMD670 had a favorable safety profile and led to clinically relevant improvements in the quantitative myasthenia gravis (QMG) total score. This translational study spanning from single muscle fiber recordings to patients provides proof of mechanism for ClC-1 inhibition as a potential therapeutic approach in MG and supports further development of NMD670.


Asunto(s)
Cloruros , Miastenia Gravis , Humanos , Ratas , Animales , Cloruros/uso terapéutico , Miastenia Gravis/tratamiento farmacológico , Músculo Esquelético/fisiología , Unión Neuromuscular , Canales de Cloruro
15.
Biosens Bioelectron ; 253: 116166, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38428069

RESUMEN

Eccrine sweat can serve as a source of biomarkers for assessing physiological health and nutritional balance, for tracking loss of essential species from the body and for evaluating exposure to hazardous substances. The growing interest in this relatively underexplored class of biofluid arises in part from its non-invasive ability for capture and analysis. The simplest devices, and the only ones that are commercially available, exploit soft microfluidic constructs and colorimetric assays with purely passive modes of operation. The most sophisticated platforms exploit batteries, electronic components and radio hardware for inducing sweat, for electrochemical evaluation of its content and for wireless transmission of this information. The work reported here introduces a technology that combines the advantages of these two different approaches, in the form of a cost-effective, easy-to-use device that supports on-demand evaluation of multiple biomarkers in sweat. This flexible, skin-interfaced, miniaturized system incorporates a hydrogel that contains an approved drug to activate eccrine sweat glands, electrodes and a simple circuit and battery to delivery this drug by iontophoresis through the surface of the skin, microfluidic channels and microreservoirs to capture the induced sweat, and multiple colorimetric assays to evaluate the concentrations of chloride, zinc, and iron. As demonstrated in healthy human participants monitored before and after a meal, such devices yield results that match those of traditional laboratory analysis techniques. Clinical studies that involve cystic fibrosis pediatric patients illustrate the use of this technology as a simple, painless, and reliable alternative to traditional hospital systems for measurements of sweat chloride.


Asunto(s)
Técnicas Biosensibles , Sudor , Humanos , Niño , Cloruros , Colorimetría , Biomarcadores
16.
Environ Sci Pollut Res Int ; 31(19): 27935-27948, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38523212

RESUMEN

Herein, microwave-assisted activated carbon (MW-AC) was fabricated from peanut shells using a ZnCl2 activator and utilized for the first time to eliminate benzene vapor as a volatile organic compound (VOC). During the MW-AC production process, which involved two steps-microwave treatment and muffle furnace heating-we investigated the effects of various factors and achieved the highest iodine number of 1250 mg/g. This was achieved under optimal operating conditions, which included a 100% impregnation ratio, CO2 as the gas in the microwave environment, a microwave power set at 500 W, a microwave duration of 10 min, an activation temperature of 500 °C and an activation time of 45 min. The structural and morphological properties of the optimized MW-AC were assessed through SEM, FTIR, and BET analysis. The dynamic adsorption process of benzene on the optimized MW-AC adsorbent, which has a significant BET surface area of 1204.90 m2/g, was designed using the Box-Behnken approach within the response surface methodology. Under optimal experimental conditions, including a contact duration of 80 min, an inlet concentration of 18 ppm, and a temperature of 26 °C, the maximum adsorption capacity reached was 568.34 mg/g. The experimental data are better described by the pseudo-second-order kinetic model, while it is concluded that the equilibrium data are better described by the Langmuir isotherm model. MW-AC exhibited a reuse efficiency of 86.54% for benzene vapor after five consecutive recycling processes. The motivation of the study highlights the high adsorption capacity and superior reuse efficiency of MW-AC adsorbent with high BET surface area against benzene pollutant. According to our results, the developed MW-AC presents itself as a promising adsorbent candidate for the treatment of VOCs in various industrial applications.


Asunto(s)
Arachis , Benceno , Carbón Orgánico , Microondas , Compuestos de Zinc , Adsorción , Benceno/química , Carbón Orgánico/química , Compuestos de Zinc/química , Arachis/química , Compuestos Orgánicos Volátiles/química , Cloruros/química , Cinética , Contaminantes Atmosféricos/química
17.
Pancreatology ; 24(3): 394-403, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38493004

RESUMEN

BACKGROUND: Many affected by pancreatitis harbor rare variants of the cystic fibrosis (CF) gene, CFTR, which encodes an epithelial chloride/bicarbonate channel. We investigated CFTR function and the effect of CFTR modulator drugs in pancreatitis patients carrying CFTR variants. METHODS: Next-generation sequencing was performed to identify CFTR variants. Sweat tests and nasal potential difference (NPD) assays were performed to assess CFTR function in vivo. Intestinal current measurement (ICM) was performed on rectal biopsies. Patient-derived intestinal epithelial monolayers were used to evaluate chloride and bicarbonate transport and the effects of a CFTR modulator combination: elexacaftor, tezacaftor and ivacaftor (ETI). RESULTS: Of 32 pancreatitis patients carrying CFTR variants, three had CF-causing mutations on both alleles and yielded CF-typical sweat test, NPD and ICM results. Fourteen subjects showed a more modest elevation in sweat chloride levels, including three that were provisionally diagnosed with CF. ICM indicated impaired CFTR function in nine out of 17 non-CF subjects tested. This group of nine included five carrying a wild type CFTR allele. In epithelial monolayers, a reduction in CFTR-dependent chloride transport was found in six out of 14 subjects tested, whereas bicarbonate secretion was reduced in only one individual. In epithelial monolayers of four of these six subjects, ETI improved CFTR function. CONCLUSIONS: CFTR function is impaired in a subset of pancreatitis patients carrying CFTR variants. Mutations outside the CFTR locus may contribute to the anion transport defect. Bioassays on patient-derived intestinal tissue and organoids can be used to detect such defects and to assess the effect of CFTR modulators.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística , Fibrosis Quística , Pancreatitis , Humanos , Bicarbonatos/metabolismo , Cloruros , Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Mutación , Pancreatitis/genética , Pancreatitis/metabolismo , Quinolonas
18.
Int J Biol Macromol ; 266(Pt 1): 131208, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38552695

RESUMEN

In this study, three activators and two activation methods were employed to activate sesame lignin-based biochar. The biochar samples were comprehensively characterized, their abilities to adsorb benzo[a]pyrene (BaP) from sesame oil were assessed, and the mechanism was analyzed. The results showed that the biochar obtained by one-step activation was more effective in removing BaP from sesame oil than the biochar produced by two-step activation. Among them, the biochar generated by one-step activation with ZnCl2 as the activator had the largest specific surface area (1068.8776 m3/g), and the richest mesoporous structure (0.7891 m3/g); it removed 90.53 % of BaP from sesame oil. BaP was mainly adsorbed by the mesopores of biochar. Mechanistically, pore-filling, π-π conjugations, hydrogen bonding, and n-π interactions were involved. The adsorption was spontaneous and heat-absorbing. In conclusion, the preparation of sesame lignin biochar using one-step activation with ZnCl2 as the activator was found to be the best for removing BaP from sesame oil. This biochar may be an economical adsorbent for the industrial removal of BaP from sesame oil.


Asunto(s)
Benzo(a)pireno , Carbón Orgánico , Lignina , Aceite de Sésamo , Sesamum , Carbón Orgánico/química , Lignina/química , Benzo(a)pireno/química , Adsorción , Aceite de Sésamo/química , Sesamum/química , Compuestos de Zinc/química , Cloruros/química
19.
Toxicol Appl Pharmacol ; 485: 116904, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38503349

RESUMEN

Manganese (Mn)-induced pulmonary toxicity and the underlying molecular mechanisms remain largely enigmatic. Further, in recent years, microRNAs (miRNAs) have emerged as regulators of several pollutants-mediated toxicity. In this context, our study aimed at elucidating whether miRNAs are involved in manganese (II) chloride (MnCl2) (Mn2+)-induced cytotoxicity in lung epithelial cells. Growth inhibition of Mn2+ towards normal human bronchial epithelial (BEAS-2B) and adenocarcinomic human alveolar basal epithelial (A549) cells was analyzed by MTT assay following 24 or 48 h treatment. Reactive oxygen species (ROS) generation, mitochondrial membrane potential (ΔΨm), cell cycle arrest, and apoptosis were evaluated by flow cytometry. RT-qPCR and Western blot were performed to analyze the expression of cyclins, anti-oxidant genes, and miRNAs. We used small RNA sequencing to investigate Mn2+-induced changes in miRNA expression patterns. In both cell lines, Mn2+ treatment inhibited growth in a dose-dependent manner. Further, compared with vehicle-treated cells, Mn2+ (250 µM) treatment induced ROS generation, cell cycle arrest, apoptosis, and decreased ΔΨm as well as altered the expression of cyclins and anti-oxidant genes. Sequencing data revealed that totally 296 miRNAs were differentially expressed in Mn2+-treated cells. Among them, miR-221-3p was one of the topmost down-regulated miRNAs in Mn2+-treated cells. We further confirmed this association in A549 cells. In addition, transient transfection was performed to study gain-of-function experiments. Forced expression of miR-221-3p significantly improved cell viability and reduced Mn2+-induced cell cycle arrest and apoptosis in BEAS-2B cells. In conclusion, miR-221-3p may be the most likely target that accounts for the cytotoxicity of Mn2+-exposed lung epithelial cells.


Asunto(s)
Apoptosis , Células Epiteliales , Pulmón , MicroARNs , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Células A549 , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Apoptosis/efectos de los fármacos , Pulmón/efectos de los fármacos , Pulmón/patología , Pulmón/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Compuestos de Manganeso , Manganeso/toxicidad , Línea Celular , Cloruros/toxicidad , Puntos de Control del Ciclo Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga
20.
Dalton Trans ; 53(13): 5993-6005, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38469684

RESUMEN

Recently, achieving selective cancer therapy with trifling side effects has been a great challenge in the eradication of cancer. Thus, to amplify the cytoselective approach of complexes, herein, we developed a series of Re(I)[2-aryl-1H-imidazo[4,5-f][1,10]phenanthroline] tricarbonyl chloride complexes and screened their potency against HeLa and MCF-7 cell lines together with the evaluation of their toxicity towards a normal kidney cell line (HEK-293). On meticulous investigation, complex [ReI(CO)3Cl(K2-N,N-(2c))] (3c) was found to be the most potent anticancer entity among other complexes. Complex 3c also showed competency to induce apoptosis in MCF-7 cells through G2/M phase cell-cycle arrest in association with the generation of ample reactive oxygen species (ROS), eventually leading to DNA intercalation and internucleosomal cleavage. The order of the cytotoxicity of these complexes depended on their lipophilic character and the electron-withdrawing halogen substitution at the para-position of the phenyl ring in the imidazophenanthroline ligand.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Neoplasias , Humanos , Fenantrolinas/farmacología , Cloruros , Células HEK293 , Antineoplásicos/farmacología , Antineoplásicos/metabolismo , ADN/metabolismo , Daño del ADN , Complejos de Coordinación/farmacología , Complejos de Coordinación/metabolismo , Apoptosis , Línea Celular Tumoral , Neoplasias/tratamiento farmacológico
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