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1.
Anal Biochem ; 682: 115336, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37806509

RESUMEN

The use of growth hormone-releasing hormones (GHRHs) is prohibited in sports according to the regulations of the World Anti-Doping Agency (WADA). Considering the complexity of urine samples and the low concentrations at which these analytes should be detected, analyzing GHRHs is a challenging task. In most of the studies, GHRHs are analyzed using UHPLC-HRMS with an orbitrap. The present developed and validated method for some GHRHs (tesamorelin, CJC-1295, sermorelin (GRF 1-29), sermorelin (3-29)-NH2, somatorelin) is based on the triple quadrupole UHPLC/MS-MS method with solid phase extraction (SPE) with weak cation exchange and is able to detect concentrations as low as 0.2 ng/mL (LOD), a limit of quantification (LOQ) at 0.6 ng/mL, and linearity across the range of 0.1 ng/mL to 1.2 ng/mL. The present method developed by our doping control laboratory was validated according to WADA technical documents for selectivity, limit of detection (LOD), carryover, reliability of detection, stability and recovery. The results show that the method has adequate recoveries and sensitivity, hence, it can be employed for routine screening in anti-doping laboratories.


Asunto(s)
Sermorelina , Espectrometría de Masas en Tándem , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Reproducibilidad de los Resultados , Extracción en Fase Sólida/métodos
2.
Int J Mol Sci ; 24(3)2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36768325

RESUMEN

A short antimicrobial peptide (AMP), rich in tryptophan and arginine (P6-HRWWRWWRR-NH2), was used in molecular dynamics (MD) simulations to investigate the interaction between AMPs and lipopolysaccharides (LPS) from two E. coli outer membrane (OM) membrane models. The OM of Gram-negative bacteria is an asymmetric bilayer, with the outer layer consisting exclusively of lipopolysaccharide molecules and the lower leaflet made up of phospholipids. The mechanisms by which short AMPs permeate the OM of Gram-negative bacteria are not well understood at the moment. For this study, two types of E. coli OM membrane models were built with (i) smooth LPS composed of lipid A, K12 core and O21 O-antigen, and (ii) rough type LPS composed of lipid A and R1 core. An OmpF monomer from E. coli was embedded in both membrane models. MD trajectories revealed that AMP insertion in the LPS layer was facilitated by the OmpF-created gap and allowed AMPs to form hydrogen bonds with the phosphate groups of inner core oligosaccharides. OM proteins such as OmpF may be essential for the permeation of short AMPs such as P6 by exposing the LPS binding site or even by direct translocation of AMPs across the OM.


Asunto(s)
Escherichia coli , Lipopolisacáridos , Escherichia coli/metabolismo , Lipopolisacáridos/metabolismo , Triptófano/metabolismo , Lípido A/metabolismo , Membrana Celular/metabolismo , Bacterias Gramnegativas/metabolismo , Péptidos Antimicrobianos
3.
J Struct Biol ; 214(4): 107919, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36356881

RESUMEN

The increased use of proton therapy has led to the need of better understanding the cellular mechanisms involved. The aim of this study was to investigate the effects induced by the accelerated proton beam in hepatocarcinoma cells. An existing facility in IFIN-HH, a 3 MV Tandetron™ accelerator, was used to irradiate HepG2 human hepatocarcinoma cells with doses between 0 and 3 Gy. Colony formation was used to assess the influence of radiation on cell long-term replication. Also, the changes induced at the mitochondrial level were shown by increased ROS and ATP levels as well as a decrease in the mitochondrial membrane potential. An increased dose has induced DNA damages and G2/M cell cycle arrest which leads to caspase 3/7 mediated apoptosis and senescence induction. Finally, the morphological and ultrastructural changes were observed at the membrane level and the nucleus of the irradiated cells. Thus, proton irradiation induces both morphological and functional changes in HepG2 cells.


Asunto(s)
Protones , Humanos , Células Hep G2 , Especies Reactivas de Oxígeno
4.
Int J Mol Sci ; 23(3)2022 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-35163769

RESUMEN

The inflammatory protease caspase-1 is associated with the release of cytokines. An excessive number of cytokines (a "cytokine storm") is a dangerous consequence of COVID-19 infection and has been indicated as being among the causes of death by COVID-19. The anti-inflammatory drug colchicine (which is reported in the literature to be a caspase-1 inhibitor) and the corticosteroid drugs, dexamethasone and methylprednisolone, are among the most effective active compounds for COVID-19 treatment. The SERM raloxifene has also been used as a repurposed drug in COVID-19 therapy. In this study, inhibition of caspase-1 by these four compounds was analyzed using computational methods. Our aim was to see if the inhibition of caspase-1, an important biomolecule in the inflammatory response that triggers cytokine release, could shed light on how these drugs help to alleviate excessive cytokine production. We also measured the antioxidant activities of dexamethasone and colchicine when scavenging the superoxide radical using cyclic voltammetry methods. The experimental findings are associated with caspase-1 active site affinity towards these compounds. In evaluating our computational and experimental results, we here formulate a mechanism for caspase-1 inhibition by these drugs, which involves the active site amino acid Cys285 residue and is mediated by a transfer of protons, involving His237 and Ser339. It is proposed that the molecular moiety targeted by all of these drugs is a carbonyl group which establishes a S(Cys285)-C(carbonyl) covalent bond.


Asunto(s)
Antiinflamatorios/farmacología , Tratamiento Farmacológico de COVID-19 , Caspasa 1/efectos de los fármacos , Inhibidores de Caspasas/farmacología , Proteasas 3C de Coronavirus/efectos de los fármacos , Antiinflamatorios/química , COVID-19/metabolismo , Caspasa 1/química , Caspasa 1/metabolismo , Inhibidores de Caspasas/química , Colchicina/química , Colchicina/farmacología , Proteasas 3C de Coronavirus/antagonistas & inhibidores , Proteasas 3C de Coronavirus/química , Proteasas 3C de Coronavirus/metabolismo , Dexametasona/farmacología , Humanos , Modelos Moleculares , Simulación del Acoplamiento Molecular , Triterpenos Pentacíclicos/farmacología , Dominios y Motivos de Interacción de Proteínas , Clorhidrato de Raloxifeno/química , Clorhidrato de Raloxifeno/farmacología , Inhibidores de Proteasa Viral/química , Inhibidores de Proteasa Viral/farmacología
5.
Int J Mol Sci ; 21(19)2020 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-33007844

RESUMEN

This study aims to investigate whether ionizing radiation combined with doxorubicin-conjugated iron oxide nanoparticles (NP-DOX) improves the internalization and cytotoxic effects of the nano-carrier-mediated drug delivery in MG-63 human osteosarcoma cells. NP-DOX was designed and synthesized using the co-precipitation method. Highly stable and crystalline nanoparticles conjugated with DOX were internalized in MG-63 cells through macropinocytosis and located in the perinuclear area. Higher nanoparticles internalization in MG-63 cells previously exposed to 1 Gy X-rays was correlated with an early accumulation of cells in G2/M, starting at 12 h after treatment. After 48 h, the application of the combined treatment led to higher cytotoxic effects compared to the individual treatment, with a reduction in the metabolic capacity and unrepaired DNA breaks, whilst a low percent of arrested cells, contributing to the commitment of mitotic catastrophe. NP-DOX showed hemocompatibility and no systemic cytotoxicity, nor histopathological alteration of the main organs.


Asunto(s)
Doxorrubicina/farmacología , Sistemas de Liberación de Medicamentos , Nanopartículas/química , Osteosarcoma/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proliferación Celular/efectos de la radiación , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Terapia Combinada , Doxorrubicina/química , Endocitosis/efectos de los fármacos , Endocitosis/efectos de la radiación , Compuestos Férricos/química , Compuestos Férricos/farmacología , Humanos , Mitosis/efectos de los fármacos , Mitosis/efectos de la radiación , Osteosarcoma/patología , Osteosarcoma/radioterapia , Radiación Ionizante
6.
J Am Chem Soc ; 141(32): 12448-12452, 2019 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-31368708

RESUMEN

Protein and peptide interactions are characterized in the liquid state by multidimensional NMR spectroscopy experiments, which can take hours to record. We show that starting from hyperpolarized HDO, two-dimensional (2D) proton correlation maps of a peptide, either free in solution or interacting with liposomes, can be acquired in less than 60 s. In standard 2D NMR spectroscopy without hyperpolarization, the acquisition time required for similar spectral correlations is on the order of hours. This hyperpolarized experiment enables the identification of amino acids featuring solvent-interacting hydrogens and provides fast spectroscopic analysis of peptide conformers. Sensitivity-enhanced 2D proton correlation spectroscopy is a useful and straightforward tool for biochemistry and structural biology, as it does not recur to nitrogen-15 or carbon-13 isotope enrichment.

7.
Future Oncol ; 15(22): 2619-2634, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31290342

RESUMEN

Aim: To identify prognostic factors of survival in patients with brain metastases (BM) and to devise a prognostic score. Patients & methods: In this single-institution retrospective study, we analyzed potential clinical prognostic factors in 1363 patients with BM. Based on the Cox proportional hazard model, we devised a BM score with three classes (score <5, 5-6 and >6). Results: The 1-year overall survival (OS) was 26%. Independent prognostic factors of OS were: age, gender, Karnofski performance status, number of BM, control of primary, presence of extracerebral metastases and type of primary tumor. The 1-year OS was 56% for score <5; 21% for score 5-6 and 4% for score >6 (p < 0.01). Conclusion: The BM score we propose is effective in grouping patients according to their prognosis and can help decision making regarding treatment adjustments.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Irradiación Craneana/métodos , Neoplasias/radioterapia , Pronóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/epidemiología , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/secundario , Niño , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/epidemiología , Neoplasias/patología , Modelos de Riesgos Proporcionales , Factores de Riesgo , Adulto Joven
8.
Int J Mol Sci ; 20(8)2019 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-31013625

RESUMEN

The neuron-specific Elav-like Hu RNA-binding proteins were described to play an important role in neuronal differentiation and plasticity by ensuring the post-transcriptional control of RNAs encoding for various proteins. Although Elav-like Hu proteins alterations were reported in diabetes or neuropathy, little is known about the regulation of neuron-specific Elav-like Hu RNA-binding proteins in sensory neurons of dorsal root ganglia (DRG) due to the diabetic condition. The goal of our study was to analyze the gene and protein expression of HuB, HuC, and HuD in DRG sensory neurons in diabetes. The diabetic condition was induced in CD-1 adult male mice with single-intraperitoneal injection of streptozotocin (STZ, 150 mg/kg), and 8-weeks (advanced diabetes) after induction was quantified the Elav-like proteins expression. Based on the glycemia values, we identified two types of responses to STZ, and mice were classified in STZ-resistant (diabetic resistant, glycemia < 260 mg/dL) and STZ-sensitive (diabetic, glycemia > 260 mg/dL). Body weight measurements indicated that 8-weeks after STZ-induction of diabetes, control mice have a higher increase in body weight compared to the diabetic and diabetic resistant mice. Moreover, after 8-weeks, diabetic mice (19.52 ± 3.52 s) have longer paw withdrawal latencies in the hot-plate test than diabetic resistant (11.36 ± 1.92 s) and control (11.03 ± 1.97 s) mice, that correlates with the installation of warm hypoalgesia due to the diabetic condition. Further on, we evidenced the decrease of Elav-like gene expression in DRG neurons of diabetic mice (Elavl2, 0.68 ± 0.05 fold; Elavl3, 0.65 ± 0.01 fold; Elavl4, 0.53 ± 0.07 fold) and diabetic resistant mice (Ealvl2, 0.56 ± 0.07 fold; Elavl3, 0.32 ± 0.09 fold) compared to control mice. Interestingly, Elav-like genes have a more accentuated downregulation in diabetic resistant than in diabetic mice, although hypoalgesia was evidenced only in diabetic mice. The Elav-like gene expression changes do not always correlate with the Hu protein expression changes. To detail, HuB is upregulated and HuD is downregulated in diabetic mice, while HuB, HuC, and HuD are downregulated in diabetic resistant mice compared to control mice. To resume, we demonstrated HuD downregulation and HuB upregulation in DRG sensory neurons induced by diabetes, which might be correlated with altered post-transcriptional control of RNAs involved in the regulation of thermal hypoalgesia condition caused by the advanced diabetic neuropathy.


Asunto(s)
Proteína 2 Similar a ELAV/genética , Proteína 3 Similar a ELAV/genética , Proteína 4 Similar a ELAV/genética , Ganglios Espinales/citología , Ganglios Espinales/metabolismo , Regulación de la Expresión Génica , Células Receptoras Sensoriales/metabolismo , Animales , Biomarcadores , Glucemia , Peso Corporal , Diabetes Mellitus Experimental , Proteína 2 Similar a ELAV/metabolismo , Proteína 3 Similar a ELAV/metabolismo , Proteína 4 Similar a ELAV/metabolismo , Ganglios Espinales/fisiopatología , Inmunohistoquímica , Ratones , Proteínas de Unión al ARN
9.
Int J Mol Sci ; 20(16)2019 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-31412656

RESUMEN

The generic term "melanin" describes a black pigment of biological origin, although some melanins can be brown or even yellow. The pigment is characterized as a heterogenic polymer of phenolic or indolic nature, and the classification of eu-, pheo- and allo- melanin is broadly accepted. This classification is based on the chemical composition of the monomer subunit structure of the pigment. Due to the high heterogeneity of melanins, their analytical characterization can be a challenging task. In the present work, we synthesized the current information about the analytical methods which can be applied in melanin analysis workflow, from extraction and purification to high-throughput methods, such as matrix-assisted laser desorption/ionization mass-spectrometry or pyrolysis gas chromatography. Our thorough comparative evaluation of analytical data published so far on melanin analysis has proven to be a difficult task in terms of finding equivalent results, even when the same matrix was used. Moreover, we emphasize the importance of prior knowledge of melanin types and properties in order to select a valid experimental design using analytical methods that are able to deliver reliable results and draw consistent conclusions.


Asunto(s)
Melaninas/análisis , Melaninas/aislamiento & purificación , Animales , Fraccionamiento Químico , Fenómenos Químicos , Humanos , Estructura Molecular , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Análisis Espectral
10.
Medicina (Kaunas) ; 55(6)2019 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-31151305

RESUMEN

Background and objectives: In the last few years, graphene oxide has attracted much attention in biomedical applications due to its unique physico-chemical properties and can be used as a carrier for both hydrophilic and/or hydrophobic biomolecules. The purpose of this paper was to synthesize graphene oxide and to obtain multifunctional platforms based on graphene oxide as a nanocarrier loaded with few biologically active substances with anticancer, antimicrobial or anti-inflammatory properties such as gallic acid, caffeic acid, limonene and nutmeg and cembra pine essential oils. Materials and Methods: Graphene oxide was obtained according to the method developed by Hummers and further loaded with biologically active agents. The obtained platforms were characterized using FTIR, HPLC, TGA, SEM, TEM and Raman spectroscopy. Results: Gallic acid released 80% within 10 days but all the other biologically active agents did not release because their affinity for the graphene oxide support was higher than that of the phosphate buffer solution. SEM characterization showed the formation of nanosheets and a slight increase in the degree of agglomeration of the particles. The ratio I2D/IG for all samples was between 0.18 for GO-cembra pine and 0.27 for GO-limonene, indicating that the GO materials were in the form of multilayers. The individual GO sheets were found to have less than 20 µm, the thickness of GO was estimated to be ~4 nm and an interlayer spacing of about 2.12 Å. Raman spectroscopy indicated that the bioactive substances were adsorbed on the surface and no degradation occurred during loading. Conclusions: These findings encourage this research to further explore, both in vitro and in vivo, the biological activities of bioactive agents for their use in medicine.


Asunto(s)
Productos Biológicos/uso terapéutico , Grafito/uso terapéutico , Nanoestructuras/uso terapéutico , Productos Biológicos/farmacología , Cromatografía Líquida de Alta Presión/métodos , Tomografía con Microscopio Electrónico/métodos , Grafito/farmacología , Humanos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Espectrometría Raman/métodos
11.
Analyst ; 143(10): 2356-2362, 2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-29687793

RESUMEN

Boron-doped diamond (BDD) electrodes were used to investigate the possibility of detecting N-hydroxysuccinimide (NHS) by linear sweep anodic voltammetry. By increasing the pH the peak potential corresponding to NHS oxidation gradually decreases, suggesting that the electroactive species are the deprotonated ones. An exponential enhancement of the peak current with increasing pH was also observed, indicating that the overall process involves OH--mediated regeneration of these species. The sweep rate effect, together with digital simulation, allowed ascribing the anodic peak to a mechanism consisting of a slow uptake of an electron from the deprotonated NHS species, followed by their catalytic regeneration through a fast chemical reaction. It was also found that in alkaline media the voltammetric response is suitable for analytical applications. A method was proposed for the determination of NHS in the concentration range 5 µM to 10 mM. The good analytical performance characteristics and the wide dynamic range of analytically useful response are also meaningful as they might come in useful in providing a basis for new, electrochemical, approaches for NHS quantification.

12.
Adv Exp Med Biol ; 1088: 73-92, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30390248

RESUMEN

Muscle atrophy typically is a direct effect of protein degradation induced by a diversity of pathophysiologic states such as disuse, immobilization, denervation, aging, sepsis, cachexia, glucocorticoid treatment, hereditary muscular disorders, cancer, diabetes and obesity, kidney and heart failure, and others. Muscle atrophy is defined by changes in the muscles, consisting in shrinkage of myofibers, changes in the types of fiber and myosin isoforms, and a net loss of cytoplasm, organelles and overall a protein loss. Although in the literature there are extensive studies in a range of animal models, the paucity of human data is a reality. This chapter is focused on various aspects of muscle wasting and describes the transitions of myofiber types during the progression of muscle atrophy in several pathological states. Clinical conditions associated with muscle atrophy have been grouped based on the fast-to-slow or slow-to-fast fiber-type shifts. We have also summarized the ultrastructural and histochemical features characteristic for muscle atrophy in clinical and experimental models for aging, cancer, diabetes and obesity, and heart failure and arrhythmia.


Asunto(s)
Músculo Esquelético/fisiopatología , Atrofia Muscular/fisiopatología , Envejecimiento/patología , Animales , Arritmias Cardíacas/fisiopatología , Diabetes Mellitus/fisiopatología , Insuficiencia Cardíaca/fisiopatología , Humanos , Miofibrillas/patología , Miosinas , Neoplasias/fisiopatología , Obesidad/fisiopatología , Isoformas de Proteínas
13.
Int J Mol Sci ; 19(5)2018 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-29747396

RESUMEN

Voltage-gated calcium channels and estrogen receptors are essential players in uterine physiology, and their association with different calcium signaling pathways contributes to healthy and pathological conditions of the uterine myometrium. Among the properties of the various cell subtypes present in human uterine myometrium, there is increasing evidence that calcium oscillations in telocytes (TCs) contribute to contractile activity and pregnancy. Our study aimed to evaluate the effects of beta-estradiol on voltage-gated calcium channels and estrogen receptors in TCs from human uterine myometrium and to understand their role in pregnancy. For this purpose, we employed patch-clamp recordings, ratiometric Fura-2-based calcium imaging analysis, and qRT-PCR techniques for the analysis of cultured human myometrial TCs derived from pregnant and non-pregnant uterine samples. In human myometrial TCs from both non-pregnant and pregnant uterus, we evidenced by qRT-PCR the presence of genes encoding for voltage-gated calcium channels (Cav3.1, Ca3.2, Cav3.3, Cav2.1), estrogen receptors (ESR1, ESR2, GPR30), and nuclear receptor coactivator 3 (NCOA3). Pregnancy significantly upregulated Cav3.1 and downregulated Cav3.2, Cav3.3, ESR1, ESR2, and NCOA3, compared to the non-pregnant condition. Beta-estradiol treatment (24 h, 10, 100, 1000 nM) downregulated Cav3.2, Cav3.3, Cav1.2, ESR1, ESR2, GRP30, and NCOA3 in TCs from human pregnant uterine myometrium. We also confirmed the functional expression of voltage-gated calcium channels by patch-clamp recordings and calcium imaging analysis of TCs from pregnant human myometrium by perfusing with BAY K8644, which induced calcium influx through these channels. Additionally, we demonstrated that beta-estradiol (1000 nM) antagonized the effect of BAY K8644 (2.5 or 5 µM) in the same preparations. In conclusion, we evidenced the presence of voltage-gated calcium channels and estrogen receptors in TCs from non-pregnant and pregnant human uterine myometrium and their gene expression regulation by beta-estradiol in pregnant conditions. Further exploration of the calcium signaling in TCs and its modulation by estrogen hormones will contribute to the understanding of labor and pregnancy mechanisms and to the development of effective strategies to reduce the risk of premature birth.


Asunto(s)
Canales de Calcio/metabolismo , Estradiol/farmacología , Miometrio/citología , Receptores de Estrógenos/metabolismo , Telocitos/metabolismo , Ácido 3-piridinacarboxílico, 1,4-dihidro-2,6-dimetil-5-nitro-4-(2-(trifluorometil)fenil)-, Éster Metílico/farmacología , Adulto , Canales de Calcio/genética , Señalización del Calcio/efectos de los fármacos , Células Cultivadas , Regulación hacia Abajo/efectos de los fármacos , Femenino , Humanos , Persona de Mediana Edad , Embarazo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Telocitos/efectos de los fármacos
14.
Biochim Biophys Acta Gen Subj ; 1861(7): 1844-1854, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28372989

RESUMEN

BACKGROUND: High antimicrobial efficacy of short tryptophan-and arginine-rich peptides makes them good candidates in the fight against pathogens. Substitution of tryptophan and arginine by histidine could be used to modulate the peptides efficacy by optimizing their structures. METHODS: The peptide (RRWWRWWRR), reported to showed good antimicrobial efficacy, was used as template, seven new analogs being designed substituting tryptophan or arginine with histidine. The peptides' efficacy was tested against E. coli, B. subtilis and S. aureus. The cytotoxicity and hemolytic effect were evaluated and the therapeutic index was inferred for each peptide. Atomic force microscopy and molecular simulation were used to analyze the effects of peptides on bacterial membrane. RESULTS: The substitution of tryptophan by histidine proved to strongly modulate the antimicrobial activity, mainly by changing the peptide-to-membrane binding energy. The substitution of arginine has low effect on the antimicrobial efficacy. The presence of histidine residue reduced the cytotoxic and hemolytic activity of the peptides in some cases maintaining the same efficacy against bacteria. The peptides' antimicrobial activity was correlated to the 3D-hydrophobic moment and to a simple structure-based packing parameter. CONCLUSION: The results show that some of these peptides have the potential to become good candidates to fight against bacteria. The substitution by histidine proved to fine tune the therapeutic index allowing the optimization of the peptide structure mainly by changing its binding energy and 3D-hydrophobic moment. GENERAL SIGNIFICANCE: The short tryptophan reach peptides therapeutic index can be maximized using the histidine substitution to optimize their structure.


Asunto(s)
Antiinfecciosos/farmacología , Péptidos/farmacología , Arginina , Membrana Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Hemólisis/efectos de los fármacos , Histidina , Humanos , Modelos Moleculares , Staphylococcus aureus/efectos de los fármacos , Relación Estructura-Actividad , Triptófano
15.
Int J Mol Sci ; 18(2)2017 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-28208829

RESUMEN

In this review, we describe the current knowledge on calcium signaling pathways in interstitial cells with a special focus on interstitial cells of Cajal (ICCs), interstitial Cajal-like cells (ICLCs), and telocytes. In detail, we present the generation of Ca2+ oscillations, the inositol triphosphate (IP3)/Ca2+ signaling pathway and modulation exerted by cytokines and vasoactive agents on calcium signaling in interstitial cells. We discuss the physiology and alterations of calcium signaling in interstitial cells, and in particular in telocytes. We describe the physiological contribution of calcium signaling in interstitial cells to the pacemaking activity (e.g., intestinal, urinary, uterine or vascular pacemaking activity) and to the reproductive function. We also present the pathological contribution of calcium signaling in interstitial cells to the aortic valve calcification or intestinal inflammation. Moreover, we summarize the current knowledge of the role played by calcium signaling in telocytes in the uterine, cardiac and urinary physiology, and also in various pathologies, including immune response, uterine and cardiac pathologies.


Asunto(s)
Señalización del Calcio , Calcio/metabolismo , Células del Tejido Conectivo/metabolismo , Telocitos/metabolismo , Animales , Señalización del Calcio/efectos de los fármacos , Células del Tejido Conectivo/clasificación , Células del Tejido Conectivo/ultraestructura , Citocinas/metabolismo , Humanos , Inmunofenotipificación , Inflamación/metabolismo , Inflamación/patología , Células Intersticiales de Cajal/metabolismo , Células Intersticiales de Cajal/ultraestructura , Fenotipo , Telocitos/ultraestructura
16.
Molecules ; 22(7)2017 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-28657606

RESUMEN

Nanotechnology has been successfully used for the fabrication of targeted anti-cancer drug carriers. This study aimed to obtain Fe3O4 nanoparticles functionalized with Gemcitabine to improve the cytotoxic effects of the chemotherapeutic substance on cancer cells. The (un) functionalized magnetite nanoparticles were synthesized using a modified co-precipitation method. The nanoconjugate characterization was performed by XRD, SEM, SAED and HRTEM; the functionalizing of magnetite with anti-tumor substances has been highlighted through TGA. The interaction with biologic media has been studied by means of stability and agglomeration tendency (using DLS and Zeta Potential); also, the release kinetics of the drug in culture media was evaluated. Cytotoxicity of free-Gemcitabine and the obtained nanoconjugate were evaluated on human BT 474 breast ductal carcinoma, HepG2 hepatocellular carcinoma and MG 63 osteosarcoma cells by MTS. In parallel, cellular morphology of these cells were examined through fluorescence microscopy and SEM. The localization of the nanoparticles related to the cells was studied using SEM, EDX and TEM. Hemolysis assay showed no damage of erythrocytes. Additionally, an in vivo biodistribution study was made for tracking where Fe3O4@Gemcitabine traveled in the body of mice. Our results showed that the transport of the drug improves the cytotoxic effects in comparison with the one produced by free Gemcitabine for the BT474 and HepG2 cells. The in vivo biodistribution test proved nanoparticle accumulation in the vital organs, with the exception of spleen, where black-brown deposits have been found. These results indicate that our Gemcitabine-functionalized nanoparticles are a promising targeted system for applications in cancer therapy.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Desoxicitidina/análogos & derivados , Nanopartículas de Magnetita/química , Antineoplásicos/efectos adversos , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Desoxicitidina/efectos adversos , Desoxicitidina/química , Desoxicitidina/farmacología , Eritrocitos/efectos de los fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Nanotecnología/métodos , Gemcitabina
17.
Biochim Biophys Acta ; 1828(2): 365-72, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23000110

RESUMEN

Dielectrophoresis was employed to distinguish the electroporated from non-electroporated cells. It was found that the electric field frequency at which cells change the direction of their movement (the crossover frequency f(CO)) is higher when cells are electroporated. The contribution to the cell dielectrophoretic behavior of four electric and geometrical cell parameters was analyzed using a single shell model. f(CO) measurements were performed in media with conductivities of 0.001-0.09S/m, on B16F10 cells which were electroporated in a Mannitol solution (0.001S/m), using rectangular or exponential pulses. The control cells' f(CO) was found in a domain of 2 to 105 kHz, while the electroporated cells' f(CO) was in a domain of 5 to 350 kHz, depending on the external media conductivities. At exterior conductivities above ~0.02S/m, f(CO) of electroporated cells became significantly higher compared to controls. Even though the possible contribution of membrane permittivity to explain the observed f(CO) shift toward higher values cannot be excluded, the computations highlight the fact that the variation of cytosol conductivity might be the major contributor to the dielectrophoretic behavior change. Our experimental observations can be described by considering a linear dependence of electroporated cells' cytosol conductivity against external conductivity.


Asunto(s)
Membrana Celular/metabolismo , Electroforesis/métodos , Electroporación/métodos , Animales , Línea Celular Tumoral , Separación Celular , Simulación por Computador , Citosol/metabolismo , Conductividad Eléctrica , Campos Electromagnéticos , Citometría de Flujo , Manitol/química , Melanoma Experimental , Ratones , Microfluídica/métodos
18.
J Photochem Photobiol B ; 250: 112833, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38141326

RESUMEN

The solvatochromic dye Laurdan is widely used in sensing the lipid packing of both model and biological membranes. The fluorescence emission maximum shifts from about 440 nm (blue channel) in condensed membranes (So) to about 490 nm (green channel) in the liquid-crystalline phase (Lα). Although the fluorescence intensity based generalized polarization (GP) is widely used to characterize lipid membranes, the fluorescence lifetime of Laurdan, in the blue and the green channel, is less used for that purpose. Here we explore the correlation between GP and fluorescence lifetimes by spectroscopic measurements on the So and Lα phases of large unilamellar vesicles of DMPC and DPPC. A positive correlation between GP and the lifetimes is observed in each of the optical channels for the two lipid phases. Microfluorimetric determinations on giant unilamellar vesicles of DPPC and DOPC at room temperature are performed under linearly polarized two-photon excitation to disentangle possible subpopulations of Laurdan at a scale below the optical resolution. Fluorescence intensities, GP and fluorescence lifetimes depend on the angle between the orientation of the linear polarization of the excitation light and the local normal to the membrane of the optical cross-section. This angular variation depends on the lipid phase and the emission channel. GP and fluorescence intensities in the blue and green channel in So and in the blue channel in Lα exhibit a minimum near 90o. Surprisingly, the intensity in the green channel in Lα reaches a maximum near 90o. The fluorescence lifetimes in the two optical channels also reach a pronounced minimum near 90o in So and Lα, apart from the lifetime in the blue channel in Lα where the lifetime is short with minimal angular variation. To our knowledge, these experimental observations are the first to demonstrate the existence of a bent conformation of Laurdan in lipid membranes, as previously suggested by molecular dynamics calculations.


Asunto(s)
Lauratos , Liposomas Unilamelares , Membrana Celular , Lauratos/análisis , Lauratos/química , 2-Naftilamina/química , Colorantes Fluorescentes/química , Polarización de Fluorescencia
19.
Cureus ; 16(6): e62110, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38863776

RESUMEN

Introduction Urosepsis is a systemic, dysregulated, inflammatory reaction to a urinary tract infection and can have severe effects on all systems, which can often lead to multi-organ failure and death. Sepsis-associated delirium is a common complication in critically ill patients, contributing to adverse outcomes and prolonged hospital stays. The neutrophil-to-lymphocyte ratio (NLR) has emerged as a potential biomarker for sepsis severity and prognosis. Material and methods Our study investigates the utility of NLR in the diagnostic strategies for urosepsis-associated delirium in a cohort of 76 patients with sepsis and septic shock admitted to the Intensive Care Unit (ICU). We performed a single-centre retrospective observational study in the Craiova Clinical Emergency Hospital between June and October 2023. Results Patients with urological conditions that were diagnosed with urosepsis included 76 patients. These patients were clustered as follows: a group with delirium (37 patients, 48.7%) and another group without delirium (39 patients, 51.3%). Complete blood count parameters were obtained upon admission, and delirium was assessed using standardized diagnostic criteria. We identified a strong significant positive correlation between elevated NLR values on ICU admission and the development of delirium during hospitalization in urosepsis patients. Receiver operating characteristic (ROC) analysis showed similar diagnostic performance for NLR score. Conclusions The findings suggest that NLR may serve as a valuable biomarker for early detection, risk stratification, and guiding therapeutic interventions in urosepsis-associated delirium, thus improving outcomes in critically ill patients.

20.
Diagnostics (Basel) ; 14(5)2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38472928

RESUMEN

This case report details the application and outcomes of a novel therapeutic approach involving hyperthermic intraperitoneal chemotherapy (HIPEC) and hyperthermic intrathoracic chemotherapy (HITOC) in a single patient diagnosed with advanced ovarian neoplasm. The treatment protocol included pleural cytoreductive surgery (CRS) and HITOC followed by a second surgical intervention consisting of peritoneal CRS and HIPEC. HIPEC targeted the intraperitoneal space with heated chemotherapy, while HITOC extended the thermal perfusion to the thoracic cavity. The patient has shown significant progression in disease-free survival over one year and eight months of observation, demonstrating lower recurrence rates and an overall survival outcome exceeding expectations based on conventional therapy outcomes. The combined modality demonstrated a manageable toxicity profile, with no significant increase in peri- or postoperative complications observed.

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