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1.
J Appl Toxicol ; 42(2): 274-284, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34102705

RESUMEN

The accumulation of advanced glycation end products (AGEs) causes metabolic dysfunction and neuronal cell damage. Methylglyoxal (MG) is a major glycating agent that reacts with basic residues present in proteins and promotes the formation of AGEs. Sciadopitysin, a type of biflavonoid, exerts protective effects against neuronal cell damage; however, the underlying mechanisms have not been studied. This study aimed to investigate the mechanisms underlying the protective effects of sciadopitysin against MG-mediated cytotoxicity in SK-N-MC neuroblastoma cells. Our results demonstrated that pretreatment of SK-N-MC cells with sciadopitysin improved the cell viability that was inhibited by MG and inhibited the apoptosis induced by MG. Sciadopitysin attenuated intracellular Ca2+ , NOX4 levels, oxidative stress, and MG-protein adduct levels, and increased nuclear Nrf2 and glyoxalase 1 levels in the presence of MG. These results suggest that sciadopitysin exerts neuroprotective effects against MG-induced death of human SK-N-MC cells via its antioxidative action. This study highlights sciadopitysin as a promising candidate for antioxidant therapy and designing natural drugs against AGE-induced neurodegenerative disorders.


Asunto(s)
Biflavonoides/farmacología , Indicadores y Reactivos/toxicidad , Fármacos Neuroprotectores/farmacología , Piruvaldehído/toxicidad , Línea Celular , Humanos
2.
Anal Chem ; 91(10): 6577-6584, 2019 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-31025855

RESUMEN

Protein footprinting coupled with mass spectrometry is being increasingly used for the study of protein interactions and conformations. The hydroxyl radical footprinting method, fast photochemical oxidation of proteins (FPOP), utilizes hydroxyl radicals to oxidatively modify solvent accessible amino acids. Here, we describe the further development of FPOP for protein structural analysis in vivo (IV-FPOP) with Caenorhabditis elegans. C. elegans, part of the nematode family, are used as model systems for many human diseases. The ability to perform structural studies in these worms would provide insight into the role of structure in disease pathogenesis. Many parameters were optimized for labeling within the worms including the microfluidic flow system and hydrogen peroxide concentration. IV-FPOP was able to modify several hundred proteins in various organs within the worms. The method successfully probed solvent accessibility similarily to in vitro FPOP, demonstrating its potential for use as a structural technique in a multiorgan system. The coupling of the method with mass spectrometry allows for amino-acid-residue-level structural information, a higher resolution than currently available in vivo methods.


Asunto(s)
Caenorhabditis elegans/química , Huella de Proteína/métodos , Proteínas/análisis , Animales , Caenorhabditis elegans/efectos de los fármacos , Cromatografía Liquida , Peróxido de Hidrógeno/farmacología , Peróxido de Hidrógeno/toxicidad , Indicadores y Reactivos/farmacología , Indicadores y Reactivos/toxicidad , Oxidación-Reducción , Proteínas/química , Espectrometría de Masas en Tándem
3.
J Am Chem Soc ; 140(38): 11926-11930, 2018 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-30196699

RESUMEN

Many dynamic biological processes are regulated by protein-protein interactions and protein localization. Experimental techniques to probe such processes with temporal and spatial precision include photoactivatable proteins and chemically induced dimerization (CID) of proteins. CID has been used to study several cellular events, especially cell signaling networks, which are often reversible. However, chemical dimerizers that can be both rapidly activated and deactivated with high spatiotemporal resolution are currently limited. Herein, we present a novel chemical inducer of protein dimerization that can be rapidly turned on and off using single pulses of light at two orthogonal wavelengths. We demonstrate the utility of this molecule by controlling peroxisome transport and mitotic checkpoint signaling in living cells. Our system highlights and enhances the spatiotemporal control offered by CID. This tool addresses biological questions on subcellular levels by controlling protein-protein interactions.


Asunto(s)
Proteínas Bacterianas/metabolismo , Cumarinas/química , Indicadores y Reactivos/química , Trimetoprim/química , Proteínas Bacterianas/química , Cumarinas/toxicidad , Diseño de Fármacos , Escherichia coli/enzimología , Células HeLa , Humanos , Indicadores y Reactivos/toxicidad , Cinetocoros/metabolismo , Listeria monocytogenes/química , Mitocondrias/metabolismo , Peroxisomas/metabolismo , Multimerización de Proteína , Rhodococcus/enzimología , Trimetoprim/toxicidad , Rayos Ultravioleta
4.
Regul Toxicol Pharmacol ; 94: 172-182, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29408293

RESUMEN

This paper provides compound-specific toxicology limits for 20 widely used synthetic reagents and common by-products that are potential impurities in drug substances. In addition, a 15 µg/day class-specific limit was developed for monofunctional alkyl bromides, aligning this with the class-specific limit previously defined for monofunctional alkyl chlorides. Both the compound- and class-specific toxicology limits assume a lifetime chronic exposure for the general population (including sensitive subpopulations) by all routes of exposure for pharmaceuticals. Inhalation-specific toxicology limits were also derived for acrolein, formaldehyde, and methyl bromide because of their localized toxicity via that route. Mode of action was an important consideration for a compound-specific toxicology limit. Acceptable intake (AI) calculations for certain mutagenic carcinogens assumed a linear dose-response for tumor induction, and permissible daily exposure (PDE) determination assumed a non-linear dose-response. Several compounds evaluated have been previously incorrectly assumed to be mutagenic, or to be mutagenic carcinogens, but the evidence reported here for such compounds indicates a lack of mutagenicity, and a non-mutagenic mode of action for tumor induction. For non-mutagens with insufficient data to develop a toxicology limit, the ICH Q3A qualification thresholds are recommended. The compound- and class-specific toxicology limits described here may be adjusted for an individual drug substance based on treatment duration, dosing schedule, severity of the disease and therapeutic indication.


Asunto(s)
Bromuros/normas , Carcinógenos/normas , Contaminación de Medicamentos , Indicadores y Reactivos/normas , Mutágenos/normas , Animales , Bromuros/clasificación , Bromuros/toxicidad , Carcinógenos/toxicidad , Industria Farmacéutica , Humanos , Indicadores y Reactivos/toxicidad , Mutágenos/toxicidad , Medición de Riesgo
5.
Lett Appl Microbiol ; 66(1): 32-37, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29117447

RESUMEN

The aim of this work was to evaluate a fungal DNA extraction procedure with the lowest inputs in terms of time as well as of expensive and toxic chemicals, but able to consistently produce genomic DNA of good quality for PCR purposes. Two types of fungal biological material were tested - mycelium and conidia - combined with two protocols for DNA extraction using Sodium Dodecyl Sulphate (SDS) and Cetyl Trimethyl Ammonium Bromide as extraction buffers and glass beads for mechanical disruption of cell walls. Our results showed that conidia and SDS buffer was the combination that lead to the best DNA quality and yield, with the lowest variation between samples. This study clearly demonstrates that it is possible to obtain high yield and pure DNA from pigmented conidia without the use of strong cell disrupting procedures and of toxic reagents. SIGNIFICANCE AND IMPACT OF THE STUDY: There are numerous methods for DNA extraction from fungi. Some rely on expensive commercial kits and/or equipments, unavailable for many laboratories, or make use of toxic chemicals such as chloroform, phenol and mercaptoethanol. This study clearly demonstrates that it is possible to obtain high yields of pure DNA from pigmented conidia without the use of strong and expensive cell disrupting procedures and of toxic reagents. The method herein described is simultaneously inexpensive and adequate to DNA extraction from several different types of fungi.


Asunto(s)
ADN de Hongos/genética , Equipos y Suministros/economía , Hongos/genética , Técnicas Genéticas/instrumentación , Pared Celular/química , ADN de Hongos/aislamiento & purificación , Hongos/aislamiento & purificación , Técnicas Genéticas/economía , Indicadores y Reactivos/toxicidad , Laboratorios/economía , Reacción en Cadena de la Polimerasa , Esporas Fúngicas/química
6.
Clin Exp Ophthalmol ; 46(7): 796-808, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29417735

RESUMEN

BACKGROUND: To investigate and compare the cytotoxicity of indocyanine green (ICG), brilliant blue G (BBG) and trypan blue (TB) using ARPE-19 cells that have been pre-treated/post-treated with balanced salt solution (BSS) or foetal bovine serum (FBS). METHODS: The cultured human retina pigment epithelium ARPE-19 cells were pre-treated/post-treated with BSS or FBS (represent the autologous serum in clinic) in parallel with cells being soaked with various concentrations of ICG, BBG and TB. The cells were then assessed for viability, growth rate, reactive oxygen species (ROS) level, mitochondrial membrane potential (Δψ) and mitochondrial mass as cytotoxic indices. For the FBS pre-treated cells, only ROS was examined. RESULTS: Using the MTT assay, cytotoxicity seemed to appear when the dye concentration was above 2.5 mg/mL for ICG but no cytotoxicity for BBG and TB at the concentrations used. Cell growth was arrested at a concentration 1 mg/mL when ICG or BBG were present but no arrest at any of the tested concentrations was found for TB with the cell-growth curve was slowest for ICG. Cellular ROS levels increased at all concentrations of all dyes, but the increasing slopes were decreased after FBS post-treatment washout. CONCLUSIONS: As a rinse buffer FBS performs much better than BSS in terms of cell rescue, which agrees with a clinical report when autologous whole blood was applied to macular hole surgery. However, FBS pre-treatment seems to be much better than FBS use as washout buffer in post-treatment.


Asunto(s)
Membrana Basal/cirugía , Verde de Indocianina/toxicidad , Perforaciones de la Retina/cirugía , Epitelio Pigmentado de la Retina/patología , Colorantes de Rosanilina/toxicidad , Suero , Azul de Tripano/toxicidad , Animales , Membrana Basal/patología , Bovinos , Supervivencia Celular , Células Cultivadas , Colorantes/toxicidad , Humanos , Indicadores y Reactivos/toxicidad , Periodo Intraoperatorio , Perforaciones de la Retina/diagnóstico , Epitelio Pigmentado de la Retina/efectos de los fármacos , Vitrectomía
7.
Neuromodulation ; 20(1): 81-87, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27730701

RESUMEN

OBJECTIVE: To determine the role of opioid, ß-adrenergic, and metabotropic glutamate 5 receptors in sacral neuromodulation of bladder overactivity. MATERIAL AND METHODS: In α-chloralose anesthetized cats, intravesical infusion of 0.5% acetic acid (AA) irritated the bladder and induced bladder overactivity. Electric stimulation (5 Hz, 0.2 ms, 0.16-0.7V) of S1 or S2 sacral dorsal roots inhibited the bladder overactivity. Naloxone, propranolol, or MTEP were given intravenously (i.v.) to determine different neurotransmitter mechanisms. RESULTS: AA significantly (p < 0.05) reduced bladder capacity to 7.7 ± 3.3 mL from 12.0 ± 5.0 mL measured during saline infusion. S1 or S2 stimulation at motor threshold intensity significantly (p < 0.05) increased bladder capacity to 179.4 ± 20.0% or 219.1 ± 23.0% of AA control, respectively. Naloxone (1 mg/kg) significantly (p < 0.001) reduced the control capacity to 38.3 ± 7.3% and the bladder capacity measured during S1 stimulation to 106.2 ± 20.8% of AA control, but did not significantly change the bladder capacity measured during S2 stimulation. Propranolol (3 mg/kg) significantly (p < 0.01) reduced bladder capacity from 251.8 ± 32.2% to 210.9 ± 33.3% during S2 stimulation, but had no effect during S1 stimulation. A similar propranolol effect also was observed in naloxone-pretreated cats. In propranolol-pretreated cats during S1 or S2 stimulation, MTEP (3 mg/kg) significantly (p < 0.05) reduced bladder capacity and naloxone (1 mg/kg) following MTEP treatment further reduced bladder capacity. However, a significant inhibition could still be induced by S1 or S2 stimulation after all three drugs were administered. CONCLUSIONS: Neurotransmitter mechanisms in addition to those activating opioid, ß-adrenergic, and metabotropic glutamate 5 receptors also are involved in sacral neuromodulation.


Asunto(s)
Neurotransmisores/metabolismo , Estimulación de la Médula Espinal/métodos , Raíces Nerviosas Espinales/fisiología , Vejiga Urinaria Hiperactiva/metabolismo , Vejiga Urinaria Hiperactiva/terapia , Ácido Acético/toxicidad , Antagonistas Adrenérgicos beta/uso terapéutico , Análisis de Varianza , Animales , Gatos , Modelos Animales de Enfermedad , Antagonistas de Aminoácidos Excitadores/uso terapéutico , Femenino , Indicadores y Reactivos/toxicidad , Masculino , Naloxona/uso terapéutico , Antagonistas de Narcóticos/uso terapéutico , Propranolol/uso terapéutico , Piridinas/uso terapéutico , Sacro , Tiazoles/uso terapéutico , Vejiga Urinaria Hiperactiva/inducido químicamente
8.
Anal Chem ; 88(19): 9518-9523, 2016 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-27599001

RESUMEN

Hypochlorite (ClO-) and glutathione (GSH) have been reported to closely correlate with oxidative stress and related diseases; however, a clear mechanism is still unknown, mainly owing to a lack of accurate analytical methods for live cells. Herein we create a novel surface-enhanced Raman scattering (SERS) nanoprobe, 4-mercaptophenol (4-MP)-functionalized gold flowers (AuF/MP), for imaging and biosensing of ClO- and GSH in RAW 264.7 macrophage cells upon oxidative stress. The SERS spectra of AuF/MP change with the reaction between ClO- and 4-MP on AuFs within 1 min and then recover after reaction with GSH, resulting in the ratiometric detection of ClO- and GSH with high accuracy. The single SERS probe also shows high selectivity for ClO- and GSH detection against other reactive oxygen species and amino acids which may exist in biological systems, as well as remarkable sensitivity ascribed to a larger amount of hot spots on AuFs. The significant analytical performance of the developed nanoprobe, together with good biocompatibility and high cell-permeability, enables the present SERS probe imaging and real-time detection of ClO- and GSH in live cells upon oxidative stress.


Asunto(s)
Técnicas Biosensibles/métodos , Glutatión/análisis , Ácido Hipocloroso/análisis , Indicadores y Reactivos/farmacología , Nanoestructuras/química , Animales , Oro/química , Indicadores y Reactivos/química , Indicadores y Reactivos/toxicidad , Ratones , Nanoestructuras/toxicidad , Estrés Oxidativo , Fenoles/química , Fenoles/toxicidad , Células RAW 264.7 , Espectrometría Raman/métodos , Compuestos de Sulfhidrilo/química , Compuestos de Sulfhidrilo/toxicidad
9.
Anal Biochem ; 490: 52-4, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26278168

RESUMEN

N-sulfonated oversulfated chondroitin sulfate (NS-OSCS), recently reported as a potential threat to the heparin supply, was prepared along with its intermediate derivatives. All compounds were spiked into marketplace heparin and subjected to United States Pharmacopeia (USP) identification assays for heparin (proton nuclear magnetic resonance [(1)H NMR], chromatographic identity, % galactosamine [%GalN], anti-factor IIa potency, and anti-factor Xa/IIa ratio). The U.S. Food and Drug Administration (FDA) strong-anionic exchange high-performance liquid chromatography (SAX-HPLC) method resolved NS-OSCS from heparin and OSCS and had a limit of detection of 0.26% (w/w) NS-OSCS. The %GalN test was sensitive to the presence of NS-OSCS in heparin. Therefore, current USP heparin monograph tests (i.e., SAX-HPLC and %GalN) detect the presence of NS-OSCS in heparin.


Asunto(s)
Anticoagulantes/química , Sulfatos de Condroitina/análisis , Contaminación de Medicamentos , Heparina/química , Indicadores y Reactivos/análisis , Resinas de Intercambio Aniónico , Anticoagulantes/farmacología , Sulfatos de Condroitina/química , Sulfatos de Condroitina/toxicidad , Cromatografía Líquida de Alta Presión , Dimetilformamida/química , Contaminación de Medicamentos/prevención & control , Galactosamina/análisis , Heparina/farmacología , Hidrazinas/química , Indicadores y Reactivos/química , Indicadores y Reactivos/toxicidad , Límite de Detección , Espectroscopía de Protones por Resonancia Magnética , Control de Calidad , Estados Unidos , United States Food and Drug Administration
10.
Arch Toxicol ; 89(9): 1579-88, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26233687

RESUMEN

Primary hepatocyte cell cultures are widely used for studying hepatic diseases with alterations in hepatic glucose and lipid metabolism, such as diabetes and non-alcoholic fatty liver disease. Therefore, small interfering RNAs (siRNAs) provide a potent and specific tool to elucidate the signaling pathways and gene functions involved in these pathologies. Although RNA interference (RNAi) in vitro is frequently used in these investigations, the metabolic alterations elucidated by different siRNA delivery strategies have hardly been investigated in transfected hepatocytes. To elucidate the influence of the most commonly used lipid-based transfection reagents on cultured primary hepatocytes, we studied the cytotoxic effects and transfection efficiencies of INTERFERin(®), Lipofectamine(®)RNAiMAX, and HiPerFect(®). All of these transfection agents displayed low cytotoxicity (5.6-9.0 ± 1.3-3.4%), normal cell viability, and high transfection efficiency (fold change 0.08-0.13 ± 0.03-0.05), and they also favored the satisfactory down-regulation of target gene expression. However, when effects on the metabolome and lipidome were studied, considerable differences were observed among the transfection reagents. Cellular triacylglycerides levels were either up- or down-regulated [maximum fold change: INTERFERin(®) (48 h) 2.55 ± 0.34, HiPerFect(®) (24 h) 0.79 ± 0.08, Lipofectamine(®)RNAiMAX (48 h) 1.48 ± 0.21], and mRNA levels of genes associated with lipid metabolism were differentially affected. Likewise, metabolic functions such as amino acid utilization from were perturbed (alanine, arginine, glycine, ornithine, and pyruvate). In conclusion, these findings demonstrate that the choice of non-viral siRNA delivery agent is critical in hepatocytes. This should be remembered, especially if RNA silencing is used for studying hepatic lipid homeostasis and its regulation.


Asunto(s)
Hepatocitos/efectos de los fármacos , Indicadores y Reactivos/administración & dosificación , Lípidos/administración & dosificación , ARN Interferente Pequeño/administración & dosificación , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Regulación hacia Abajo/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Hepatocitos/metabolismo , Indicadores y Reactivos/química , Indicadores y Reactivos/toxicidad , Lípidos/química , Lípidos/toxicidad , Masculino , Ratones , Ratones Endogámicos C57BL , Interferencia de ARN , ARN Mensajero/metabolismo , Transfección
11.
Mutat Res ; 746(1): 15-20, 2012 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-22414563

RESUMEN

Neutral red (Nr) is relatively non-toxic and is widely used as indicator dye in many biological test systems. It absorbs visible light and is known to act as a photosensitizer, involving the generation of reactive oxygen species (type-I reaction) and singlet oxygen (type-II reaction). The mutagenicity of Nr was determined in the Ames test (with Salmonella typhimurium strains TA1535, TA97, TA98, TA98NR, TA100, and TA102) with and without metabolic activation, and with and without photo-activation on agar plates. Similarly to the situation following metabolic activation, photo-mutagenicity of Nr was seen with all Salmonella strains tested, albeit with different effects between these strains. To our knowledge, Nr is the only photo-mutagen showing such a broad action. Since the effects are also observed in strains not known to be responsive to ROS, this indicates that ROS production is not the sole mode of action that leads to photo-genotoxicity. The reactive species produced by irradiation are short-lived as pre-irradiation of an Nr solution did not produce mutagenic effects when added to the bacteria. In addition, mutagenicity in TA98 following irradiation was stronger than in the nitroreductase-deficient strain TA98NR, indicating that nitro derivatives that are transformed by bacterial nitroreductase to hydroxylamines appear to play a role in the photo-mutagenicity of Nr. Photo-genotoxicity of Nr was further investigated in the comet assay and micronucleus test in L5178Y cells. Concentration-dependent increases in primary DNA damage and in the frequency of micronuclei were observed after irradiation.


Asunto(s)
Indicadores y Reactivos/toxicidad , Mutágenos/toxicidad , Rojo Neutro/toxicidad , Biotransformación , Ensayo Cometa , Daño del ADN/efectos de los fármacos , Daño del ADN/efectos de la radiación , Luz , Pruebas de Micronúcleos , Pruebas de Mutagenicidad , Rojo Neutro/metabolismo , Rojo Neutro/efectos de la radiación , Salmonella typhimurium/genética
12.
J Toxicol Environ Health A ; 75(11): 637-48, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22712849

RESUMEN

Female F344 rats were exposed to 4,4'-methylenebis(N,N'-dimethyl)aniline (MDA) by dietary feed at concentrations of 0, 50, 200, 375, 500, or 750 ppm for 5 d, 2 wk, 4 wk, and 13 wk duration. Endpoints evaluated included clinical observations, body weights, thyroid weights, serum thyroid hormones, blood MDA, gross pathology, and thyroid histopathology. There were no MDA exposure-related clinical signs of toxicity. Mean body weight decreased 5% compared to control in the 750 ppm group during study wk 6 through 13. Serum TSH increased and serum T4 and T3 levels decreased with increasing feed concentrations of MDA and time of exposure. Thyroid weight increases were both concentration- and exposure time-dependent and statistically significant at ≥375 ppm. Incidence and severity of decreased colloid, follicular cell hypertrophy and follicular cell hyperplasia were also related to MDA concentration and exposure time. A no-observed-adverse-effect level (NOAEL) of 200 ppm was selected based on the statistically significant increase in incidence of follicular cell hyperplasia at concentrations ≥375 ppm.


Asunto(s)
Compuestos de Anilina/toxicidad , Indicadores y Reactivos/toxicidad , Glándula Tiroides/efectos de los fármacos , Administración Oral , Compuestos de Anilina/administración & dosificación , Compuestos de Anilina/sangre , Compuestos de Anilina/farmacocinética , Animales , Carcinógenos/administración & dosificación , Carcinógenos/análisis , Carcinógenos/farmacocinética , Carcinógenos/toxicidad , Relación Dosis-Respuesta a Droga , Contaminantes Ambientales/administración & dosificación , Contaminantes Ambientales/sangre , Contaminantes Ambientales/farmacocinética , Contaminantes Ambientales/toxicidad , Femenino , Hiperplasia , Hipertrofia , Indicadores y Reactivos/administración & dosificación , Indicadores y Reactivos/análisis , Indicadores y Reactivos/farmacocinética , Nivel sin Efectos Adversos Observados , Tamaño de los Órganos/efectos de los fármacos , Distribución Aleatoria , Ratas , Ratas Endogámicas F344 , Glándula Tiroides/crecimiento & desarrollo , Glándula Tiroides/patología , Neoplasias de la Tiroides/inducido químicamente , Tirotropina/sangre , Tiroxina/sangre , Triyodotironina/sangre
13.
Molecules ; 17(8): 9056-69, 2012 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-22847144

RESUMEN

A new poly(aminoester) (EPAE-FA) containing folic acid and amino groups in the backbone and side chain was synthesized. EPAE-FA self-assembled readily with the plasmid DNA (pCMV-ßgal) in HEPES buffer and was characterized by dynamic light scattering, zeta potential, fluorescence images, and XTT cell viability assays. To evaluate the transfection effect of graft ratio of FA on the EPAE system, EPAE-FA polymers with two different graft ratios (EPAE-FA12k and EPAE-FA14k) were also prepared. This study found that all EPAE-FA polymers were able to bind plasmid DNA and yielded positively charged complexes with nano-sized particles (< 200 nm). To assess the transfection efficiency mediated by EPAE and EPAE-FA polymers, we performed in vitro transfection activity assays using FR-negative (COS-7) and FR-positive (HeLa) cells. The EPAE-FA12k/DNA and EPAE-FA14k/DNA complexes were able to transfect HeLa cell in vitro with higher transfection efficiency than PEI25k/DNA at the similar weight ratio. These results demonstrated that the introduction of FA into EPAE system had a significant effect on transferring ability for FR-positive cells (HeLa). Examination of the cytotoxicity of PEI25k and EPAE-FA system revealed that EPAE-FA system had lower cytotoxicity. In this paper, EPAE-FA seemed to be a novel cationic poly(aminoester) for gene delivery and an interesting candidate for further study.


Asunto(s)
Ácido Fólico/análogos & derivados , Ácido Fólico/síntesis química , Indicadores y Reactivos/síntesis química , Poliaminas/síntesis química , Transfección , Animales , Células COS , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , ADN/química , ADN/genética , Electroforesis en Gel de Agar , Ácido Fólico/toxicidad , Proteínas Fluorescentes Verdes/biosíntesis , Proteínas Fluorescentes Verdes/genética , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Indicadores y Reactivos/toxicidad , Tamaño de la Partícula , Plásmidos/química , Plásmidos/genética , Poliaminas/toxicidad , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/genética , Volumetría
14.
Artículo en Japonés | MEDLINE | ID: mdl-23243987

RESUMEN

The method prescribed in the 8th edition of Japan's Specifications and Standards for Food Additives (JSSFA) for the quantitative analysis of thiabendazole was improved by eliminating the use of toxic reagents such as mercuric acetate and chromium trioxide. For exclusion of mercuric acetate, a nonaqueous titration was performed using four types of solvent systems, including acetic acid:acetic anhydride (1:5), acetic acid:acetic anhydride (3:7), acetic acid alone, and formic acid:acetic acid (1:10), that did not contain mercuric compounds. Because precipitates were formed in titrations using acetic acid alone and formic acid:acetic acid (1:10), we considered that it was difficult to determine the purity using these solvent systems. However, it was confirmed that the purity of thiabendazole dissolved in the two acetic acid:acetic anhydride solvent systems can be determined using either a visual indicator or potentiometry. Specifically, the purity of thiabendazole was determined to be 99.9% (relative standard deviation (RSD) = 0.07%) for acetic acid:acetic anhydride (1:5) and 99.7% (RSD = 0.13%) for acetic acid:acetic anhydride (3:7) With respect to chromium trioxide, it was determined that chromium trioxide can be excluded using acetic acid, which conforms to the JIS K8001 standard for nonaqueous titrations. Therefore, in this study, an improved method for the quantitative determination of thiabendazole was developed without the use of toxic reagents.


Asunto(s)
Técnicas de Química Analítica/métodos , Tiabendazol/química , Ácido Acético , Anhídridos Acéticos , Compuestos de Cromo/toxicidad , Indicadores y Reactivos/toxicidad , Mercurio/toxicidad , Solventes
15.
Life Sci ; 288: 120205, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34871665

RESUMEN

AIMS: This study was aimed to explore whether sacran polysaccharide has a therapeutic effect on atopic dermatitis (AD) and its possible mechanisms. MATERIALS AND METHODS: 2, 4-dinitrochlorobenzene (DNCB)-induced AD mice were treated with 0.2% Sacran, 0.5% Sacran and 0.1% tacrolimus. Through scoring dermatitis severity, measuring ear thickness, cracking behavior, open field test, we evaluated the therapeutic effect of Sacran on DNCB-induced AD mice. CD4+ T cells and CD8+ T cells were evaluated by flow cytometry. The relative expression of Ifng and Il4 were measured by real-time quantitative PCR. KEY FINDINGS: Sacran could relieved the symptoms of DNCB-induced AD mice, such as AD score, ear thickness, and IgE release. Sacran may alleviate dermatitis by inhibiting Th2 activation and reducing IgE release. SIGNIFICANCE: Our research further proved that polysaccharide Sacran has anti-dermatitis effects, and also clarified its mechanism of alleviating dermatitis by inhibiting the activation of Th2 cells and reducing the release of IgE, which provides a theoretical basis for the future clinical transformation of polysaccharide Sacran.


Asunto(s)
Dermatitis Atópica/tratamiento farmacológico , Dinitroclorobenceno/toxicidad , Inmunoglobulina E/metabolismo , Inflamación/prevención & control , Polisacáridos/farmacología , Células Th2/inmunología , Animales , Dermatitis Atópica/inducido químicamente , Dermatitis Atópica/inmunología , Dermatitis Atópica/patología , Femenino , Indicadores y Reactivos/toxicidad , Inflamación/etiología , Ratones , Ratones Endogámicos BALB C , Células Th2/efectos de los fármacos
16.
Food Chem Toxicol ; 156: 112528, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34474067

RESUMEN

Heptafluorobutyric acid (PFBA) is a synthetic chemical belonging to the per- and polyfluoroalkyl substances (PFAS) group that includes over 5000 chemicals incorporated into numerous products. PFBA is a short-chain PFAS (C4) labeled as a safer alternative to legacy PFAS which have been linked to numerous health effects. Despite the high potential for dermal exposure, occupationally and environmentally, dermal exposure studies are lacking. Using a murine model, this study analyzed serum chemistries, histology, immune phenotyping, and gene expression to evaluate the systemic toxicity of sub-chronic dermal PFBA 15-day (15% v/v or 375 mg/kg/dose) or 28-day (3.75-7.5% v/v or 93.8-187.5 mg/kg/dose) exposures. PFBA exposure produced significant increases in liver and kidney weights and altered serum chemistries (all exposure levels). Immune-cell phenotyping identified significant increases in draining lymph node B-cells (15%) and CD11b + cells (3.75-15%) and skin T-cells (3.75-15%) and neutrophils (7.5-15%). Histopathological and gene expression changes were observed in both the liver and skin after dermal PFBA exposure. The findings indicate PFBA induces liver toxicity and alterations of PPAR target genes, suggesting a role of a PPAR pathway. These results demonstrate that sustained dermal exposure to PFBA induces systemic effects and raise concerns of short-chain PFAS being promoted as safer alternatives.


Asunto(s)
Contaminantes Ambientales/toxicidad , Fluorocarburos/toxicidad , Indicadores y Reactivos/toxicidad , Administración Tópica , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas , Femenino , Ratones
17.
Org Biomol Chem ; 8(3): 640-7, 2010 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-20090982

RESUMEN

Linear cyclen-based polyamine (LCPA, M(w) = 7392, M(w)/M(n) = 1.19) as a novel non-viral gene vector was designed and synthesized from 1,7-diprotected 1,4,7,10-tetraazacyclododecane (cyclen), bis(beta-hydroxylethyl)amine and epichlorohydrin. Agarose gel retardation and fluorescent titration using ethidium bromide showed the good DNA-binding ability of LCPA. It could retard pDNA at an N/P ratio of 4 and form polyplexes with sizes around 250-300 nm from an N/P ratio of 10 to 60 and relatively lower zeta-potential values (< +3 mV) even at the N/P ratio of 60. The cytotoxicity of LCPA assayed by MTT is much lower than that of 25 kDa PEI. In vitro transfection against A549 and 293 cells showed that the transfection efficiency of LCPA/DNA polyplexes is close to that of 25 kDa PEI at an N/P ratio of 10-15, indicating that the new material could be a promising non-viral polycationic reagent for gene delivery.


Asunto(s)
Técnicas de Transferencia de Gen , Compuestos Heterocíclicos/química , Poliaminas/química , Poliaminas/metabolismo , Tampones (Química) , Línea Celular , Ciclamas , ADN/metabolismo , Electroforesis en Gel de Agar , Epiclorhidrina/química , Humanos , Concentración de Iones de Hidrógeno , Indicadores y Reactivos/síntesis química , Indicadores y Reactivos/química , Indicadores y Reactivos/metabolismo , Indicadores y Reactivos/toxicidad , Tamaño de la Partícula , Plásmidos/genética , Poliaminas/síntesis química , Poliaminas/toxicidad , Transfección
18.
Occup Environ Med ; 67(5): 348-50, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19884651

RESUMEN

INTRODUCTION: In 1991, the US National Institute for Occupational Safety and Health (NIOSH) reported an increased bladder cancer risk in a cohort of 1749 workers potentially exposed to o-toluidine and aniline at a chemical manufacturing plant. As additional information showed that workers in certain departments had been misclassified regarding o-toluidine exposure, we therefore conducted a reanalysis of the data using updated exposure categories. METHODS: We updated exposure categories based on information ascertained during a plant walkthrough, documents on file at the plant, interviews with current and former employees, and answers provided by company and union officials to specific questions. Bladder cancer incidence was determined through 31 December 1988 and mortality through 31 December 1994. RESULTS: Thirteen cases of bladder cancer were observed versus 3.57 expected (New York State rates excluding New York City) (standardised incidence ratio (SIR) 3.64, 95% CI 1.94 to 6.23). Among workers classified as definitely exposed, increasing risks were observed for longer duration of employment (for > or = 10 years, standardised rate ratio (SRR) 6.07, 95% CI 0.77 to 48.17) and time since first employment in the exposed departments (for > or = 20 years, SRR 3.39, 95% CI 0.40 to 29.03). One bladder cancer death was observed among those definitely exposed. CONCLUSIONS: These findings are comparable to the results reported earlier by NIOSH, and confirm that workers in this plant have an increased risk of bladder cancer.


Asunto(s)
Compuestos de Anilina/toxicidad , Indicadores y Reactivos/toxicidad , Enfermedades Profesionales/epidemiología , Exposición Profesional/efectos adversos , Toluidinas/toxicidad , Neoplasias de la Vejiga Urinaria/epidemiología , Industria Química , Femenino , Humanos , Incidencia , Masculino , New York/epidemiología , Enfermedades Profesionales/inducido químicamente , Neoplasias de la Vejiga Urinaria/inducido químicamente
19.
Indian J Exp Biol ; 48(8): 817-21, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21341540

RESUMEN

Antinociceptive activity of methanolic extract of leaves of A. aspera was studied by peripheral/non-narcotic model of nociception like acetic acid induced writhing syndrome test and central/narcotic models like hot plate and tail flick tests. The methanolic extract of the plant, administered orally (@ 300, 600 and 900 mg/kg, body weight) and the standard drug (piroxicam; 10 mg/kg body weight, po) produced significant analgesic activity in acetic acid induced writhing syndrome as compared to the vehicle treated control group. In the hot plate analgesic test, in A. aspera at the above doses and the standard drug treated group (morphine sulphate @ 1.5 mg/kg, ip), the duration of reaction time (sec) increased dose dependently and significantly compared to the control group. In the tail flick test, the plant extract produced dose dependant increase in reaction time which was significantly higher in the test and standard group compared to the control group. The plant possesses significant antinociceptive property as evidenced in all the animal models of nociception. It might possibly exert its effect through diverse mechanism that may involve both central and peripheral pathways. The preliminary phytochemical investigation revealed the presence of steroids, alkaloids and triterpene in the methanolic extract of leaves of A. aspera which may be responsible for its antinociceptive activity.


Asunto(s)
Amaranthaceae/química , Analgésicos/farmacología , Modelos Animales de Enfermedad , Metanol/química , Dolor/tratamiento farmacológico , Extractos Vegetales/farmacología , Hojas de la Planta/química , Ácido Acético/toxicidad , Animales , Femenino , Indicadores y Reactivos/toxicidad , Masculino , Ratones , Dolor/inducido químicamente
20.
J Clin Invest ; 116(6): 1535-46, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16710473

RESUMEN

Dynamic and reciprocal epithelial-mesenchymal interactions are critical for the normal morphogenesis and maintenance of epithelia. Epimorphin has been identified as a unique molecule expressed by mesenchymal cells and myofibroblasts and has putative morphogenetic effects in multiple epithelial tissues, including intestine, skin, mammary gland, lung, gallbladder, and liver. To define the in vivo role of epimorphin, we created epimorphin-null mice by targeted inactivation of the epimorphin gene. Male epimorphin-/- mice are sterile due to abnormal testicular development and impaired spermatogenesis. Intestinal growth is increased in epimorphin-/- mice due to augmented crypt cell proliferation and crypt fission during the neonatal (suckling) period, mediated at least in part by changes in bone morphogenetic protein (Bmp) and Wnt/beta-catenin signaling pathways. Colonic mucosal injury and colitis induced by dextran sodium sulfate (DSS) are ameliorated in epimorphin-/- mice, probably due to the increased proliferative capacity of the epimorphin-/- colon. These in vivo findings support the notion that epimorphin is a key stromal regulator of epithelial cell proliferation and growth in the intestine. In addition, our studies demonstrate a novel and critical role for epimorphin in regulating testicular development and growth as well as spermatogenesis.


Asunto(s)
Colitis/inducido químicamente , Sulfato de Dextran/toxicidad , Intestinos/crecimiento & desarrollo , Glicoproteínas de Membrana/metabolismo , Espermatogénesis/fisiología , Animales , Proteínas Morfogenéticas Óseas/genética , Proteínas Morfogenéticas Óseas/metabolismo , Línea Celular , Colitis/patología , Femenino , Marcación de Gen , Indicadores y Reactivos/toxicidad , Intestinos/citología , Intestinos/patología , Masculino , Glicoproteínas de Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Desnudos , Morfogénesis , Testículo/citología , Testículo/patología , Testículo/fisiología , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
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