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1.
Molecules ; 28(11)2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37298772

RESUMEN

Essential oils (Eos) have demonstrated antiviral activity, but their toxicity can hinder their use as therapeutic agents. Recently, some essential oil components have been used within safe levels of acceptable daily intake limits without causing toxicity. The "ImmunoDefender," a novel antiviral compound made from a well-known mixture of essential oils, is considered highly effective in treating SARS-CoV-2 infections. The components and doses were chosen based on existing information about their structure and toxicity. Blocking the main protease (Mpro) of SARS-CoV-2 with high affinity and capacity is critical for inhibiting the virus's pathogenesis and transmission. In silico studies were conducted to examine the molecular interactions between the main essential oil components in "ImmunoDefender" and SARS-CoV-2 Mpro. The screening results showed that six key components of ImmunoDefender formed stable complexes with Mpro via its active catalytic site with binding energies ranging from -8.75 to -10.30 kcal/mol, respectively for Cinnamtannin B1, Cinnamtannin B2, Pavetannin C1, Syzyginin B, Procyanidin C1, and Tenuifolin. Furthermore, three essential oil bioactive inhibitors, Cinnamtannin B1, Cinnamtannin B2, and Pavetannin C, had significant ability to bind to the allosteric site of the main protease with binding energies of -11.12, -10.74, and -10.79 kcal/mol; these results suggest that these essential oil bioactive compounds may play a role in preventing the attachment of the translated polyprotein to Mpro, inhibiting the virus's pathogenesis and transmission. These components also had drug-like characteristics similar to approved and effective drugs, suggesting that further pre-clinical and clinical studies are needed to confirm the generated in silico outcomes.


Asunto(s)
COVID-19 , Aceites Volátiles , Humanos , Antivirales/química , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Aceites Volátiles/química , Aceites Volátiles/farmacología , Péptido Hidrolasas/metabolismo , Inhibidores de Proteasas/química , SARS-CoV-2 , Proteínas no Estructurales Virales/metabolismo
2.
J Cell Mol Med ; 24(17): 9726-9736, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32767726

RESUMEN

Gaucher disease (GD) is a genetic disease with mutations in the GBA gene that encodes glucocerebrosidase causing complications such as anaemia and bone disease. GD is characterized by accumulation of the sphingolipids (SL) glucosylceramide (GL1), glucosylsphingosine (Lyso-GL1), sphingosine (Sph) and sphingosine-1-phosphate (S1P). These SL are increased in the plasma of GD patients and the associated complications have been attributed to the accumulation of lipids in macrophages. Our recent findings indicated that red blood cells (RBCs) and erythroid progenitors may play an important role in GD pathophysiology. RBCs abnormalities and dyserythropoiesis have been observed in GD patients. Moreover, we showed higher SL levels in the plasma and in RBCs from untreated GD patients compared with controls. In this study, we quantified SL in 16 untreated GD patients and 15 patients treated with enzyme replacement therapy. Our results showed that the treatment significantly decreases SL levels in the plasma and RBCs. The increased SL content in RBCs correlates with abnormal RBC properties and with markers of disease activity. Because RBCs lack glucocerebrosidase activity, we investigated how lipid overload could occur in these cells. Our results suggested that SL overload in RBCs occurs both during erythropoiesis and during its circulation in the plasma.


Asunto(s)
Eritrocitos/metabolismo , Enfermedad de Gaucher/sangre , Glucosilceramidasa/genética , Esfingolípidos/sangre , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Niño , Preescolar , Eritropoyesis/genética , Femenino , Enfermedad de Gaucher/genética , Enfermedad de Gaucher/patología , Humanos , Lisofosfolípidos/sangre , Macrófagos/metabolismo , Masculino , Persona de Mediana Edad , Psicosina/análogos & derivados , Psicosina/sangre , Esfingosina/análogos & derivados , Esfingosina/sangre , Adulto Joven
3.
J Neurol Sci ; 396: 112-118, 2019 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-30448717

RESUMEN

OBJECTIVE: To describe the phenotype and the response to folinic acid supplementation of cerebral folate deficiency (CFD) in adults, a disorder diagnosed on low 5-methyltetrahydro-folate (5MTHF) in cerebrospinal fluid (CSF), which can correspond to a inherited disorder of folate metabolism (IDFM) or to a metabolic consequence of various neurological diseases. METHODS: We conducted a retrospective study on 224 adult patients with neurological symptoms who had a 5MTHF CSF dosage, collecting their neurologic and neuroimaging data. RESULTS: 69 patients had CFD (CSF 5MTHF level < 41 nmol/L), 25 of them had severe CFD (sCFD; ≤25 nmol/L) with adult onset neurological symptoms in 41%. 56% of sCFD patients had an underlying identified neurologic disorder, mainly mitochondrial diseases, hepatic encephalopathy and primary brain calcifications (no identified IDFM), the others were classified as undiagnosed. sCFD patients presented most frequently pyramidal syndrome (75%), movement disorders (56%), cerebellar syndrome (50%) and intellectual disability (46%). MRI findings mostly showed white matter abnormalities (WMA; 32%) and calcifications (12%), and were normal in 23%. The clinico-radiological phenotype of sCFD patients was not clearly different from non CFD patients in terms of manifestations frequency. However, their neurological picture was more complex with a higher number of combined neurological symptoms (4.7±1.6 vs 3.4±1.7, p = .01). In Magnetic Resonance Spectroscopy (MRS), Choline/Creatine (Cho/Cr) ratio was lower in sCFD patients (n = 7) compared to non-CFD patients (n = 73) (p = .005), with good sensitivity (71%) and excellent specificity (92%). Among twenty-one CFD patients treated with folinic acid, nine had a sustained improvement, all with sCFD but one (50% of sCFD patients improved). In two undiagnosed patients with extremely low 5MTHF CSF values, MRI WMA and low Cho/Cr ratios, folinic acid treatment leaded to a dramatic clinical and radiological improvement. CONCLUSION: CSF 5MTHF dosage should be considered in patients with mitochondrial diseases, primary brain calcifications and unexplained complex neurological disorders especially if associated with WMA, since folinic acid supplementation in patients with sCFD is frequently efficient.


Asunto(s)
Enfermedades Cerebelosas/complicaciones , Deficiencia de Ácido Fólico/complicaciones , Deficiencia de Ácido Fólico/genética , Mutación/genética , Proteínas/genética , Adolescente , Adulto , Anciano , Calcinosis/diagnóstico por imagen , Calcinosis/etiología , Calcinosis/genética , Enfermedades Cerebelosas/líquido cefalorraquídeo , Enfermedades Cerebelosas/diagnóstico por imagen , Enfermedades Cerebelosas/genética , Niño , Preescolar , Femenino , Ácido Fólico/líquido cefalorraquídeo , Deficiencia de Ácido Fólico/líquido cefalorraquídeo , Deficiencia de Ácido Fólico/diagnóstico por imagen , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Discapacidad Intelectual , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Enfermedades Mitocondriales/diagnóstico por imagen , Enfermedades Mitocondriales/etiología , Estudios Retrospectivos , Tetrahidrofolatos/líquido cefalorraquídeo , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Adulto Joven
4.
J Am Soc Mass Spectrom ; 29(4): 752-760, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29468501

RESUMEN

Due to their central role in biochemical processes, fast separation and identification of amino acids (AA) is of importance in many areas of the biomedical field including the diagnosis and monitoring of inborn errors of metabolism and biomarker discovery. Due to the large number of AA together with their isomers and isobars, common methods of AA analysis are tedious and time-consuming because they include a chromatographic separation step requiring pre- or post-column derivatization. Here, we propose a rapid method of separation and identification of sarcosine, a biomarker candidate of prostate cancer, from isomers using differential ion mobility spectrometry (DIMS) interfaced with a tandem mass spectrometer (MS/MS) instrument. Baseline separation of protonated sarcosine from α- and ß-alanine isomers can be easily achieved. Identification of DIMS peak is performed using an isomer-specific activation mode where DIMS- and mass-selected ions are irradiated at selected wavenumbers allowing for the specific fragmentation via an infrared multiple photon dissociation (IRMPD) process. Two orthogonal methods to MS/MS are thus added, where the MS/MS(IRMPD) is nothing but an isomer-specific multiple reaction monitoring (MRM) method. The identification relies on the comparison of DIMS-MS/MS(IRMPD) chromatograms recorded at different wavenumbers. Based on the comparison of IR spectra of the three isomers, it is shown that specific depletion of the two protonated α- and ß-alanine can be achieved, thus allowing for clear identification of the sarcosine peak. It is also demonstrated that DIMS-MS/MS(IRMPD) spectra in the carboxylic C=O stretching region allow for the resolution of overlapping DIMS peaks. Graphical Abstract ᅟ.


Asunto(s)
Sarcosina/análisis , Sarcosina/química , Espectrometría de Masas en Tándem/métodos , Isomerismo , Metabolómica , Modelos Moleculares , Espectrofotometría Infrarroja
5.
Exp Parasitol ; 183: 99-103, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29102680

RESUMEN

Acanthamoeba is a free-living amoeba genus that causes several diseases namely, amoebic keratitis which is a painful sight threatening eyes disease. Its treatment is difficult and the exploration for new drugs is very important. The main objective of the present study was to evaluate the chemical composition of the Essential Oils (EO) obtained from leaves and flowers and aerial parts of Ammoides pusilla by an alternative method "Hydrodistillation''. Identification and quantification were realized by Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography with Flame Ionization Detection (GC-FID). The main components of leaves and flowers and aerials parts were thymol (39.6% and 33.05%), γ-terpinene (28.97% and 28.19%), p-cymene (13.69% and 15.31%) and thymol methyl ether (7.33% and 8.91%), respectively. The antiparasitic activity of the EO was evaluated against Acanthamoeba castellanii Neff by the Alamar Blue® assay. Results showed that Ammoides pusilla amoebicidal activity from leaves and flowers essential oil (IC50 = 65.32 ± 5.43 µg/mL) was more important than those of aerial parts EO (IC50 = 97.18 ± 1.43 µg/ml).


Asunto(s)
Acanthamoeba castellanii/efectos de los fármacos , Apiaceae/química , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Monoterpenos Ciclohexánicos , Cimenos , Ionización de Llama , Flores/química , Cromatografía de Gases y Espectrometría de Masas , Monoterpenos/análisis , Monoterpenos/farmacología , Componentes Aéreos de las Plantas/química , Hojas de la Planta/química , Timol/análisis , Timol/farmacología , Túnez
6.
Appl Spectrosc ; 71(10): 2344-2352, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28485613

RESUMEN

There is a growing interest worldwide for the production of renewable oil without mobilizing agriculture lands; fast and reliable methods are needed to identify highly oleaginous microorganisms of potential industrial interest. The aim of this study was to demonstrate the relevance of attenuated total reflection (ATR) spectroscopy to achieve this goal. To do so, the total lipid content of lyophilized samples of five Streptomyces strains with varying lipid content was assessed with two classical quantitative but time-consuming methods, gas chromatography-mass spectrometry (GC-MS) and ATR Fourier transform infrared (ATR FT-IR) spectroscopy in transmission mode with KBr pellets and the fast ATR method, often questioned for its lack of reliability. A linear correlation between these three methods was demonstrated allowing the establishment of equations to convert ATR values expressed as CO/amide I ratio, into micrograms of lipid per milligram of biomass. The ATR method proved to be as reliable and quantitative as the classical GC-MS and FT-IR in transmission mode methods but faster and more reproducible than the latter since it involves far less manipulation for sample preparation than the two others. Attenuated total reflection could be regarded as an efficient fast screening method to identify natural or genetically modified oleaginous microorganisms by the scientific community working in the field of bio-lipids.


Asunto(s)
Ácidos Grasos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Streptomyces/química , Biocombustibles , Ácidos Grasos/química , Modelos Lineales
7.
Biomaterials ; 33(19): 4936-46, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22498298

RESUMEN

Countless studies showed that [60]fullerene (C(60)) and derivatives could have many potential biomedical applications. However, while several independent research groups showed that C(60) has no acute or sub-acute toxicity in various experimental models, more than 25 years after its discovery the in vivo fate and the chronic effects of this fullerene remain unknown. If the potential of C(60) and derivatives in the biomedical field have to be fulfilled these issues must be addressed. Here we show that oral administration of C(60) dissolved in olive oil (0.8 mg/ml) at reiterated doses (1.7 mg/kg of body weight) to rats not only does not entail chronic toxicity but it almost doubles their lifespan. The effects of C(60)-olive oil solutions in an experimental model of CCl(4) intoxication in rat strongly suggest that the effect on lifespan is mainly due to the attenuation of age-associated increases in oxidative stress. Pharmacokinetic studies show that dissolved C(60) is absorbed by the gastro-intestinal tract and eliminated in a few tens of hours. These results of importance in the fields of medicine and toxicology should open the way for the many possible -and waited for- biomedical applications of C(60) including cancer therapy, neurodegenerative disorders, and ageing.


Asunto(s)
Fulerenos/farmacología , Aceites de Plantas/química , Administración Oral , Envejecimiento/efectos de los fármacos , Animales , Fulerenos/administración & dosificación , Fulerenos/química , Fulerenos/farmacocinética , Masculino , Aceite de Oliva , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Wistar
8.
Eur J Pharm Biopharm ; 81(2): 453-7, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22465096

RESUMEN

Recent reports showed that subtle modifications of nanoparticle surface properties induced dramatic changes of interactions with serum proteins. The present work was aimed to investigate the effect of the conformation of dextran chains decorating the surface of poly(alkylcyanoacrylate) (PACA) nanoparticles on the pharmacokinetic and biodistribution of a model drug associated with the nanoparticles. Doxorubicin was associated with PACA nanoparticles prepared by anionic emulsion polymerization (AEP) (Dox-AEP) and redox radical emulsion polymerization (RREP) (Dox-RREP). Nanoparticles and the free drug (f-Dox) were injected intravenously to rats to determine the pharmacokinetic and biodistribution of doxorubicin. Curves of the pharmacokinetics showed a rapid phase of distribution followed by a slower elimination phase. Pharmacokinetic parameters of the distribution phase determined for the Dox-RREP were significantly different from those of f-Dox and Dox-AEP, while no difference was observed in the elimination phase of the three formulations. Rats treated with Dox-RREP showed lower Dox concentrations in liver but higher concentrations in heart, lungs, and kidneys compared to those treated with the other formulations. Dox-RREP exhibited a new type of stealth behavior characterized by a short circulation time and a rapid distribution in highly vascularized organs bypassing the MPS. The difference in pharmacokinetic and biodistribution observed between the drugs formulated with the two types of nanoparticles was attributed to the difference in the conformation of the dextran chains stranded on the nanoparticle surface.


Asunto(s)
Dextranos/química , Doxorrubicina/química , Doxorrubicina/farmacocinética , Nanopartículas/química , Animales , Aniones/química , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Química Farmacéutica/métodos , Portadores de Fármacos/química , Emulsiones/química , Emulsiones/farmacocinética , Masculino , Oxidación-Reducción , Polimerizacion , Ratas , Ratas Wistar , Propiedades de Superficie , Distribución Tisular
9.
J Chromatogr B Analyt Technol Biomed Life Sci ; 887-888: 128-32, 2012 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-22341684

RESUMEN

The long-term clinical use of doxorubicin (Dox), one of the most important anticancer agent in use, is limited by dose-related acute cardiotoxicity, myelo-suppression and multidrug resistance developed by cancer cells. To improve the antitumor efficacy and reduce the toxicity of Dox, many drug delivery systems have been developed, including poly(alkylcyanoacrylate) (PACA) nanoparticles. A new formulation of PACA nanoparticles with potential stealth properties were prepared by redox radical emulsion polymerization and associated to Dox in our laboratory. To comparatively investigate the pharmacokinetics and the biodistribution of different formulations of Dox associated PACA nanoparticles, a simple and rapid high performance liquid chromatographic method (HPLC) was developed for the quantification of Dox in plasma and tissues of rats treated with Dox loaded PACA nanoparticle (Dox-PACA). Dox was eluted at 4.4 min and it was well separated from its main metabolites doxorubicinol (Doxl) and doxorubicinon (Doxon) and idarubicin (Ida) used as internal standard (IS). Extraction of Dox from biological media was achieved by liquid-liquid extraction. The recovery of total Dox (i.e. free Dox and Dox associated with nanoparticles) from plasma and tissues (liver, spleen and heart) spiked with Dox-PACA were 71 and 78% for 0.05 and 1 µg/mL in rat plasma, respectively, and 73% and 80% for 0.5 and 10 µg/g in tissues, respectively. The method is linear from 0.05 to 1.5 µg/mL of Dox in plasma. The limit of detection of the method is 0.5 ng of Dox per injection (50 µL). The between-day and within-day precisions of the method were 97.1-102.9% and 97.3-101.7% for concentrations ranging from 0.05 to 1 µg/mL, respectively. Preliminary data suggested that this method can be applied to determine the pharmacokinetic and biodistribution of Dox associated with PACA nanoparticles after intravenous administration to rats.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Cianoacrilatos/química , Doxorrubicina/análisis , Nanopartículas/química , Animales , Doxorrubicina/sangre , Doxorrubicina/farmacocinética , Idarrubicina/análisis , Idarrubicina/sangre , Límite de Detección , Hígado/química , Hígado/metabolismo , Masculino , Miocardio/química , Miocardio/metabolismo , Polímeros/química , Ratas , Ratas Wistar , Reproducibilidad de los Resultados , Bazo/química , Bazo/metabolismo , Distribución Tisular
10.
J Exp Clin Cancer Res ; 29: 157, 2010 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-21134244

RESUMEN

BACKGROUND: The present report was designed to investigate the origins of elevated oxidative stress measured in cancer patients in our previous work related to a case-control study (17 cases, 43 controls) on oesophageal cancers. The aim was to characterize the relationship between the levels of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), antioxidant vitamins and genetic susceptibility. METHODS: 8-oxodG was analysed in peripheral blood mononuclear cells (PBMCs) by High Performance Liquid Chromatography with Electrochemical Detection (HPLC-ED). Analysis of gene polymorphisms in GSTM1 and GSTT1 was performed by multiplex PCR and in GSTP1 and hOGG1 by a PCR-RFLP method. Reversed-phase HPLC with UV detection at 294 nm was used to measure vitamins A and E in serum from the same blood samples. RESULTS: We observed that in our combined population (cases and control, n = 60), there was no statistically significant correlation between the levels of 8-oxodG and (i) the serum concentration of antioxidant vitamins, vitamin A (P = 0.290) or vitamin E (P = 0.813), or (ii) the incidence of the Ser326Cys polymorphic variant (P = 0.637) of the hOGG1 gene. Also, the levels of 8-oxodG were not significantly associated with polymorphisms in metabolite-detoxifying genes, such as GSTs, except for the positive correlation with Val/Val GST P1 allele (P < 0.0001). CONCLUSIONS: The weakness of our cohort size notwithstanding, vitamins levels in serum and genetic polymorphisms in the hOGG1 or GST genes do not appear to be important modulators of 8-oxodG levels.


Asunto(s)
Biomarcadores de Tumor/análisis , Desoxiguanosina/análogos & derivados , Neoplasias Esofágicas/sangre , Neoplasias Esofágicas/genética , Predisposición Genética a la Enfermedad , 8-Hidroxi-2'-Desoxicoguanosina , Antioxidantes/análisis , Antioxidantes/metabolismo , Cromatografía Líquida de Alta Presión , ADN Glicosilasas/genética , Desoxiguanosina/sangre , Glutatión Sintasa/genética , Humanos , Estrés Oxidativo/fisiología , Polimorfismo de Nucleótido Simple , Vitaminas/sangre
11.
Sleep ; 33(3): 307-14, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20337188

RESUMEN

BACKGROUND: A genetic deficiency in sepiapterin reductase leads to a combined deficit of serotonin and dopamine. The motor phenotype is characterized by a dopa-responsive fluctuating generalized dystonia-parkinsonism. The non-motor symptoms are poorly recognized. In particular, the effects of brain serotonin deficiency on sleep have not been thoroughly studied. OBJECTIVE: We examine the sleep, sleep-wake rhythms, CSF neurotransmitters, and melatonin profile in a patient with sepiapterin reductase deficiency. PATIENT: The patient was a 28-year-old man with fluctuating generalized dystonia-parkinsonism caused by sepiapterin reductase deficiency. METHODS: A sleep interview, wrist actigraphy, sleep log over 14 days, 48-h continuous sleep and core temperature monitoring, and measurement of CSF neurotransmitters and circadian serum melatonin and cortisol levels before and after treatment with 5-hydroxytryptophan (the precursor of serotonin) and levodopa were performed. RESULTS: Before treatment, the patient had mild hypersomnia with long sleep time (704 min), ultradian sleep-wake rhythm (sleep occurred every 11.8 +/- 5.3 h), organic hyperphagia, attentionlexecutive dysfunction, and no depression. The serotonin metabolism in the CSF was reduced, and the serum melatonin profile was flat, while cortisol and core temperature profiles were normal. Supplementation with 5-hydroxytryptophan, but not with levodopa, normalized serotonin metabolism in the CSF, reduced sleep time to 540 min, normalized the eating disorder and the melatonin profile, restored a circadian sleep-wake rhythm (sleep occurred every 24 +/- 1.7 h, P < 0.0001), and improved cognition. CONCLUSION: In this unique genetic paradigm, the melatonin deficiency (caused by a lack of its substrate, serotonin) may cause the ultradian sleep-wake rhythm.


Asunto(s)
Oxidorreductasas de Alcohol/deficiencia , Oxidorreductasas de Alcohol/genética , Trastornos de Somnolencia Excesiva/genética , Serotonina/deficiencia , Trastornos del Sueño del Ritmo Circadiano/genética , Sueño/genética , 5-Hidroxitriptófano/uso terapéutico , Adulto , Antidepresivos de Segunda Generación/uso terapéutico , Consanguinidad , Trastornos de Somnolencia Excesiva/tratamiento farmacológico , Trastornos de Somnolencia Excesiva/enzimología , Dopamina/deficiencia , Dopaminérgicos/uso terapéutico , Quimioterapia Combinada , Humanos , Hidrocortisona/sangre , Hiperfagia/tratamiento farmacológico , Hiperfagia/enzimología , Hiperfagia/genética , Levodopa/uso terapéutico , Masculino , Melatonina/deficiencia , Polisomnografía , Sueño/efectos de los fármacos , Trastornos del Sueño del Ritmo Circadiano/tratamiento farmacológico , Trastornos del Sueño del Ritmo Circadiano/enzimología
12.
ACS Nano ; 4(3): 1481-92, 2010 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-20175510

RESUMEN

Carbon nanotube (CNT) materials are of special interest as potential tools for biomedical applications. However, available toxicological data concerning single-walled carbon nanotubes (SWNTs) and multiwalled carbon nanotubes (MWNTs) remain contradictory. Here, we compared the effects of SWNTs as a function of dose, length, and surface chemistry in Swiss mice. Transmission electron microscopy (TEM), Raman, near-infrared (NIR), and X-ray photoelectron spectroscopies have been used to characterize the tested materials. The dose of SWNT materials used in this study is considerably higher than that proposed for most biomedical applications, but it was deemed necessary to administer such large doses to accurately assess the toxicological impact of the materials. In an acute toxicity test, SWNTs were administered orally at a dose level of 1000 mg/kg bodyweight (b.w.). Neither death nor growth or behavioral troubles were observed. After intraperitoneal administration, SWNTs, irrespective of their length or dose (50-1000 mg/kg b.w.), can coalesce inside the body to form fiberlike structures. When structure lengths exceeded 10 mum, they irremediably induced granuloma formation. Smaller aggregates did not induce granuloma formation, but they persisted inside cells for up to 5 months after administration. Short (<300 nm) well-individualized SWNTs can escape the reticuloendothelial system to be excreted through the kidneys and bile ducts. These findings suggest that if the potential of SWNTs for medical applications is to be realized, they should be engineered into discrete, individual "molecule-like" species.


Asunto(s)
Nanotubos de Carbono/química , Nanotubos de Carbono/toxicidad , Pruebas de Toxicidad , Administración Oral , Animales , Conducta Animal/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Crecimiento y Desarrollo/efectos de los fármacos , Inyecciones Intraperitoneales , Masculino , Ratones , Microscopía Electrónica de Transmisión , Propiedades de Superficie , Pruebas de Toxicidad Aguda , Pruebas de Toxicidad Crónica
13.
Adv Exp Med Biol ; 620: 181-204, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18217344

RESUMEN

As for fullerenes, the potential and the growing use of CNT and their mass production have raised several questions about their safety and environmental impact. Research on the toxicity of carbon nanotubes has just begun and the data are still fragmentary and subject to criticisms. Preliminary results highlight the difficulties in evaluating the toxicity of this new and heterogeneous carbon nanoparticle family. A number of parameters including structure, size distribution and surface area, surface chemistry and surface charge, and agglomeration state as well as purity of the samples, have considerable impact on the reactivity of carbon nanotubes. However, available data clearly show that, under some conditions, nanotubes can cross the membrane barriers and suggests that if raw materials reach the organs they can induce harmful effects as inflammatory and fibrotic reactions. Therefore, many further studies on well-characterized materials are necessary to determine the safety of carbon nanotubes as well as their environmental impact.


Asunto(s)
Nanopartículas/química , Nanotecnología/métodos , Nanotubos de Carbono/química , Nanotubos de Carbono/toxicidad , Animales , Investigación Biomédica , Carbono , Línea Celular Tumoral , Cristalización , Electroquímica/métodos , Fulerenos/toxicidad , Humanos , Conformación Molecular , Nanoestructuras
14.
Obes Surg ; 16(8): 1041-9, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16901358

RESUMEN

BACKGROUND: Roux-en-Y gastric bypass (RYGBP) is more efficient than adjustable gastric banding (AGB) in weight loss and relieving co-morbidities, but nutritional complications of each surgical procedure have been poorly evaluated. METHODS: A cross-sectional study was performed to compare nutritional parameters in 201 consecutive obese patients, who had been treated either by conventional behavioral and dietary therapy (CT, n=110) or by bariatric surgery, including 51 AGB and 40 RYGBP. RESULTS: BMI was similar after AGB (36.6 +/- 5.3 kg/m2) and RYGBP (35.4 +/- 6.3 kg/m2), but patients in the RYGBP group had lost more weight and had less metabolic disturbances than those in the AGB group. On the other hand, the prevalence of nutritional deficits was significantly higher in the RYGBP group than in the 2 other groups (P<0.01), whereas the AGB group did not differ from CT. Particularly, the RYGBP group presented an unexpected high frequency of deficiencies in fat-soluble vitamins. Moreover, vitamin B12, hemoglobin, plasma prealbumin and creatinine concentrations were low in the RYGBP group. CONCLUSION: RYGBP is more efficient than AGB in correcting obesity, but this operation is associated with a higher frequency of nutritional deficits that should be carefully monitored.


Asunto(s)
Derivación Gástrica , Gastroplastia , Estado Nutricional , Obesidad Mórbida/terapia , Adulto , Femenino , Derivación Gástrica/efectos adversos , Gastroplastia/efectos adversos , Humanos , Masculino , Obesidad Mórbida/metabolismo , Obesidad Mórbida/cirugía
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