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1.
J Helminthol ; 94: e190, 2020 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-32912343

RESUMEN

The main goal of this work was to evaluate the in vitro biological activity of two ferrocenyl chalcones (FcC-1 and FcC-2) against Haemonchus contortus (third-stage larvae (L3)) and Nacobbus aberrans (second-stage juveniles (J2)). Both compounds were synthesized and characterized by usual spectroscopic methods and their molecular structures were confirmed by single-crystal X-ray diffractometry. Nematode strains were examined in terms of percentage mortality of H. contortus (L3) by the action of FcC-1, which showed an effectivity of 100% at a concentration of 342 µM in 24 h, with EC50 = 20.33 µM and EC90 = 162.76 µM, whereas FcC-2 had an effectivity of 72% at a concentration of 342 µM in 24 h, with EC50 = 167.39 µM and EC90 = 316.21 µM. The effect of FcC-1 against nematode phytoparasite N. aberrans showed a better percentage of 95% at a concentration of 342 µM, with EC50 = 7.18 µM and EC90 = 79.25 µM, whereas the effect of FcC-2 was 87% at 342 µM, with EC50 = 168 µM and EC90 = 319.56 µM at 36 h. After treatment, the scanning electron micrographs revealed deformities in the dorsal flank and posterior part close to the tail of H. contortus L3. They showed moderate in vitro nematicidal activity against H. contortus L3 and N. aberrans J2.


Asunto(s)
Antinematodos/farmacología , Chalconas/farmacología , Compuestos Ferrosos/farmacología , Haemonchus/efectos de los fármacos , Tylenchoidea/efectos de los fármacos , Animales , Antinematodos/química , Chalconas/química , Compuestos Ferrosos/química , Hemoncosis/parasitología , Larva/efectos de los fármacos , Extractos Vegetales/farmacología
2.
Nat Mater ; 17(9): 773-777, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30082905

RESUMEN

The localization of charge carriers by electronic repulsion was suggested by Mott in the 1930s to explain the insulating state observed in supposedly metallic NiO. The Mott metal-insulator transition has been subject of intense investigations ever since1-3-not least for its relation to high-temperature superconductivity4. A detailed comparison to real materials, however, is lacking because the pristine Mott state is commonly obscured by antiferromagnetism and a complicated band structure. Here we study organic quantum spin liquids, prototype realizations of the single-band Hubbard model in the absence of magnetic order. Mapping the Hubbard bands by optical spectroscopy provides an absolute measure of the interaction strength and bandwidth-the crucial parameters that enter calculations. In this way, we advance beyond conventional temperature-pressure plots and quantitatively compose a generic phase diagram for all genuine Mott insulators based on the absolute strength of the electronic correlations. We also identify metallic quantum fluctuations as a precursor of the Mott insulator-metal transition, previously predicted but never observed. Our results suggest that all relevant phenomena in the phase diagram scale with the Coulomb repulsion U, which provides a direct link to unconventional superconductivity in cuprates and other strongly correlated materials.

3.
Nature ; 471(7340): 612-6, 2011 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-21455176

RESUMEN

A quantum spin-liquid phase is an intriguing possibility for a system of strongly interacting magnetic units in which the usual magnetically ordered ground state is avoided owing to strong quantum fluctuations. It was first predicted theoretically for a triangular-lattice model with antiferromagnetically coupled S = 1/2 spins. Recently, materials have become available showing persuasive experimental evidence for such a state. Although many studies show that the ideal triangular lattice of S = 1/2 Heisenberg spins actually orders magnetically into a three-sublattice, non-collinear 120° arrangement, quantum fluctuations significantly reduce the size of the ordered moment. This residual ordering can be completely suppressed when higher-order ring-exchange magnetic interactions are significant, as found in nearly metallic Mott insulators. The layered molecular system κ-(BEDT-TTF)(2)Cu(2)(CN)(3) is a Mott insulator with an almost isotropic, triangular magnetic lattice of spin-1/2 BEDT-TTF dimers that provides a prime example of a spin liquid formed in this way. Despite a high-temperature exchange coupling, J, of 250 K (ref. 6), no obvious signature of conventional magnetic ordering is seen down to 20 mK (refs 7, 8). Here we show, using muon spin rotation, that applying a small magnetic field to this system produces a quantum phase transition between the spin-liquid phase and an antiferromagnetic phase with a strongly suppressed moment. This can be described as Bose-Einstein condensation of spin excitations with an extremely small spin gap. At higher fields, a second transition is found that suggests a threshold for deconfinement of the spin excitations. Our studies reveal the low-temperature magnetic phase diagram and enable us to measure characteristic critical properties. We compare our results closely with current theoretical models, and this gives some further insight into the nature of the spin-liquid phase.

4.
J Chem Phys ; 144(8): 084904, 2016 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-26931723

RESUMEN

Differential Scanning Calorimetry (DSC) and optical polarization microscopy of a mixture of the liquid crystalline material (N-(4-methoxybenzylidene)-4-butylaniline, MBBA) and a Fe-based room temperature ionic liquid 1-ethyl-3-methylimidazolium tetrachloroferrate ([Emim](+) [FeCl4](-), EMIF) indicate a decrease in the nematic-isotropic (N-I) phase transition temperature (T(NI)) with an increase in EMIF concentration, explained by a proposed model of Coulomb "screening" of MBBA quadrupoles by the EMIF ions along with ionic "self screening." DSC studies of EMIF-MBBA and pure EMIF and comparison with pure MBBA results show that the major transitions in pure EMIF have Arrhenius behaviour, but more importantly the previously found convex Arrhenius behaviour of the pristine MBBA [K. Dan et al., Europhys. Lett. 108, 36007 (2014)] becomes Arrhenius in the mixture, indicating a conversion of the entropic N-I activation barrier to an enthalpic one. In presence of EMIF, a drastic decrease in the intensity of out-of-plane distortions of benzene rings in MBBA is found from Fourier transform infrared spectroscopy, consistent with significant reduction in the conformational states of MBBA. This suppression of large amplitude motion is again consistent with a Coulomb screening and gives a molecular basis for the entropic-to-enthalpic conversion of the N-I activation barrier.

5.
R Soc Open Sci ; 5(6): 172137, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30110473

RESUMEN

In this work, we report the synthesis of novel fluorescent molecules, based on 1,8-naphthalimide thio- and amino-derivatives, designed to display an OFF-ON and ON-OFF photoelectron transfer fluorescence switch upon interaction with a proton-donor drug. We have functionalized the new probes to allow easy formation of a covalent link to polymer matrices, for future applications as drug delivery sensors. We have investigated the fluorescent switch of the new probes using flufenamic acid (FA, pKa 3.65), a water insoluble, non-steroidal anti-inflammatory drug, as a model drug and proton source. The rapid interaction of the new probes with FA resulted in fluorescence enhancement or decrease and a large Stokes shift, all of which allowed the detection of the drug in the nanomolar range. The new 1,8-naphthalimide fluorescent dyes reported in this work are interesting tools for the detection and quantification of acidic drugs and biomolecules.

6.
Kyobu Geka ; 60(10): 946-9, 2007 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-17877019

RESUMEN

We reported 2 cases of acute pulmonary embolism after resection for lung cancer. A 47-year-old male was admitted to our hospital with ground-glass opacity (GGO) on a chest computed tomography (CT). We performed a right upper lobectomy and node dissection (ND) 2a dissection. Two days after the operation, he developed hypotension and hypoxemia. He was diagnosed as acute pulmonary embolism by chest CT and lung scintigram. A 68-year-old women was performed right S6 segmentectomy for lung cancer. The next day, she complained of sudden chest discomfort and dyspnea. She was diagnosed as acute pulmonary embolism by chest CT. Immediately, we started anticoagration therapy with heparin and their condition were improved. It was very important to early diagnose and start anticoagration therapy immediately for acute pulumonary embolism.


Asunto(s)
Adenocarcinoma/cirugía , Neoplasias Pulmonares/cirugía , Neumonectomía , Complicaciones Posoperatorias , Embolia Pulmonar/etiología , Enfermedad Aguda , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Embolia Pulmonar/diagnóstico por imagen , Tomografía Computarizada por Rayos X
7.
Cancer Chemother Pharmacol ; 79(6): 1077-1085, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28417167

RESUMEN

PURPOSE: Preoperative chemoradiotherapy (CRT) using 5-fluorouracil (5-FU)-based chemotherapy is the standard of care for rectal cancer. The effect of additional chemotherapy during the period between the completion of radiotherapy and surgery remains unclear. Predictive factors for CRT may differ between combination chemotherapy with S-1 and with tegafur-uracil/leucovorin (UFT/LV). METHODS: The subjects were 54 patients with locally advanced rectal cancer who received preoperative CRT with S-1 or UFT/LV. The pathological tumor response was assessed according to the tumor regression grade (TRG). The expression levels of 18 CRT-related genes were determined using RT-PCR assay. RESULTS: A pathological response (TRG 1-2) was observed in 23 patients (42.6%). In a multivariate logistic regression analysis for pathological response, the overall expression levels of four genes, HIF1A, MTHFD1, GGH and TYMS, were significant, and the accuracy rate of the predictive model was 83.3%. The effects of the gene expression levels of GGH on the response differed significantly according to the treatment regimen. The total pathological response rate of both high-GGH patients in the S-1 group and low-GGH patients in the UFT/LV group was 58.3%. CONCLUSION: Additional treatment with 5-FU-based chemotherapy during the interval between radiotherapy and surgery is not beneficial in patients who have received 5-FU-based CRT. The expression levels of four genes, HIF1A, MTHFD1, GGH and TYMS, in tumor tissues can predict the response to preoperative CRT including either S-1 or UFT/LV. In particular, the gene expression level of GGH in tumor tissues may be a useful biomarker for the appropriate use of S-1 and UFT/LV in CRT.


Asunto(s)
Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioradioterapia/métodos , Neoplasias del Recto/terapia , gamma-Glutamil Hidrolasa/biosíntesis , gamma-Glutamil Hidrolasa/genética , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/cirugía , Adulto , Anciano , Antídotos/administración & dosificación , Antimetabolitos Antineoplásicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Biomarcadores de Tumor/sangre , Terapia Combinada , Combinación de Medicamentos , Femenino , Fluorouracilo/administración & dosificación , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Leucovorina/administración & dosificación , Masculino , Persona de Mediana Edad , Ácido Oxónico/administración & dosificación , Neoplasias del Recto/tratamiento farmacológico , Neoplasias del Recto/cirugía , Reproducibilidad de los Resultados , Tegafur/administración & dosificación , Resultado del Tratamiento
8.
J Cancer Res Clin Oncol ; 121(11): 696-8, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7593136

RESUMEN

Retinoids, including all-trans-retinoic acid, its isomers, and fifty synthetic retinoids (retinobenzoic acids), were tested for differentiation-inducing activity on human leukemia cell lines HL-60 and NB4. A good linear correlation, with an r value of 0.91, between the ED50 values for the differentiation-inducing activity towards HL-60 cells and that towards NB4 cells was found.


Asunto(s)
Transformación Celular Neoplásica/efectos de los fármacos , Leucemia Promielocítica Aguda/patología , Retinoides/farmacología , Diferenciación Celular/efectos de los fármacos , Cromosomas Humanos Par 15 , Cromosomas Humanos Par 17 , Ensayos de Selección de Medicamentos Antitumorales , Regulación Leucémica de la Expresión Génica/efectos de los fármacos , Granulocitos , Humanos , Análisis de los Mínimos Cuadrados , Receptores de Ácido Retinoico/genética , Translocación Genética , Tretinoina/farmacología , Células Tumorales Cultivadas/efectos de los fármacos
9.
Am J Ophthalmol ; 122(1): 125-7, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8659589

RESUMEN

PURPOSE: To treat a 63-year-old woman who experienced fairly rapid vision loss in association with small-cell carcinoma of the lung. METHODS: She underwent a full ophthalmologic examination, including fluorescein angiography and an immunologic study by Western blot analysis. RESULTS: Fluorescein angiography demonstrated diffuse staining of the retinal vessels. She had 62-kd antiretinal antibody in her serum. Cancer-associated retinopathy was diagnosed. CONCLUSION: The staining seen on the angiogram appears to indicate vasculitis, which would cause the characteristic attenuation of retinal vessels in this disease.


Asunto(s)
Carcinoma de Células Pequeñas/complicaciones , Proteínas del Ojo , Lipoproteínas , Neoplasias Pulmonares/complicaciones , Proteínas del Tejido Nervioso , Síndromes Paraneoplásicos/etiología , Enfermedades de la Retina/etiología , Vasculitis/etiología , Antiinflamatorios/uso terapéutico , Antígenos de Neoplasias/análisis , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Autoanticuerpos/análisis , Western Blotting , Proteínas de Unión al Calcio/análisis , Carcinoma de Células Pequeñas/tratamiento farmacológico , Carcinoma de Células Pequeñas/patología , Femenino , Angiografía con Fluoresceína , Fondo de Ojo , Hipocalcina , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Persona de Mediana Edad , Síndromes Paraneoplásicos/tratamiento farmacológico , Síndromes Paraneoplásicos/patología , Prednisona/uso terapéutico , Recoverina , Enfermedades de la Retina/tratamiento farmacológico , Enfermedades de la Retina/patología , Vasculitis/tratamiento farmacológico , Vasculitis/patología
10.
J Pharm Sci ; 88(3): 347-50, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10052994

RESUMEN

The present study characterized Chinese hamster ovary cells overexpressing a human intestinal peptide transporter, CHO/hPEPT1 cells, as an in vitro model for peptidomimetic drugs. The kinetic parameters of Gly-Sar uptake were determined in three different cell culture systems such as untransfected CHO cells (CHO-K1), transfected CHO cells (CHO/hPEPT1) and Caco-2 cells. Vmax in CHO/hPEPT1 cells was approximately 3-fold higher than those in Caco-2 cells and CHO-K1 cells, while Km values were similar in all cases. The uptake of beta-lactam antibiotics in CHO/hPEPT1 cells was three to twelve fold higher than that in CHO-K1 cells, indicating that CHO/hPEPT1 cells significantly enhanced the peptide transport activity. However, amino acid drugs also exhibited high cellular uptake in both CHO-K1 and CHO/hPEPT1 cells due to the high background level of amino acid transporters. Thus, cellular uptake study in CHO/hPEPT1 cells is not sensitive enough to distinguish the peptidyl drugs from amino acid drugs. The potential of CHO/hPEPT1 cells as an in vitro model for peptidomimetic drugs was also examined through the inhibition study on Gly-Sar uptake. Peptidomimetic drugs such as beta-lactam antibiotics and enalapril significantly inhibited Gly-Sar uptake whereas the nonpeptidyl compounds, L-dopa and alpha-methyldopa, did not compete with Gly-Sar for cellular uptake within the therapeutic concentrations. In conclusion, the present study demonstrates the further characterization of CHO/hPEPT1 cells as an uptake model as well as inhibition study and suggests their utility as an alternative in vitro model for drug candidates targeting the hPEPT1 transporter.


Asunto(s)
Células CHO/metabolismo , Células CACO-2/metabolismo , Proteínas Portadoras/biosíntesis , Dipéptidos/farmacocinética , Simportadores , Animales , Transporte Biológico , Proteínas Portadoras/genética , Cricetinae , Dipéptidos/antagonistas & inhibidores , Humanos , Cinética , Transportador de Péptidos 1 , Reproducibilidad de los Resultados , Transfección
11.
J Cardiovasc Surg (Torino) ; 40(5): 749-51, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10597016

RESUMEN

We report a case of squamous cell carcinoma of the lung in which a left pneumonectomy combined resection of the pulmonary artery and aorta was performed using a cardiopulmonary bypass. The bifurcation of the pulmonary artery was repaired with a pericardial patch and the descending aorta was replaced with an artificial vessel Eleven months later, the patient underwent dissection of the contralateral mediastinal lymph nodes because of a recurrence of the disease. Even though pulmonary metastases have again recently appeared, he is alive and doing well two years after operation. To obtain a better prognosis in cases demonstrating an involvement of the bifurcation of pulmonary artery, more effective combined treatment still needs to be developed.


Asunto(s)
Aorta Torácica/cirugía , Implantación de Prótesis Vascular , Carcinoma de Células Escamosas/cirugía , Neoplasias Pulmonares/cirugía , Arteria Pulmonar/cirugía , Adulto , Materiales Biocompatibles , Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/patología , Puente Cardiopulmonar , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Escisión del Ganglio Linfático , Metástasis Linfática , Masculino , Invasividad Neoplásica , Recurrencia Local de Neoplasia , Neumonectomía/métodos , Tereftalatos Polietilenos , Radiografía , Reoperación , Tórax
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