Pegylated doxorubicin gold complex: From nanovector to potential intercalant agent for biosensor applications

We report an original approach to synthesize hybrid gold nanostructures in which doxorubicin (DOX), mixed to Poliethylenglycole diacid (PEG-COOH) led to original hybrid gold nanovector (DOX IN PEG AuNPs). In this work, we investigate the ability of DOX IN PEG-AuNPs to detect the amplification of the hybridization process by a sensitive Quartz crystal Microbalance with dissipation (QCM-D) by intercalation process. The sensing layer was carried out by self-assembled monolayer of β mercaptoethylamine (cysteamine) on gold-coated quartz crystal sensor composed by a rigid homobifunctional cross-linker 1,4 phenilenediisothiocyanate (PDITC) linked covalently with amino-probe oligonucleotides. By QCM characterization in the range from 8 µM to 20 nM, we demonstrate high specificity of DOX IN PEG-AuNPs-DNA with a limit of detection (LOD) of 9 nM. This result is very promising for development of sensitive and effective nanoparticle-based biosensor for quantifying small biomolecules concentration in physiological liquids. These results open a possibility to realize a new class of nanovector which will be tailored for different biomedical application, such as imaging, targeting and drugs delivery. Keywords: Quartz Crystal Microbalance (QCM), Chemical surface, DNA hybridization, Gold nanoparticles, Doxorubici

Pulmonary cryptococcoma: a rare and challenging diagnosis in immunocompetent patients

Cryptococcal infection is commonly seen in immunocompromised patients, although immunocompetent patients may also be infected. The pathogen’s portal of entry is the respiratory tract; however, the central nervous system is predominantly involved. Pulmonary involvement varies from interstitial and alveolar infiltrations to large masses, which are frequently first interpreted as lung neoplasm. The diagnosis of pulmonary cryptococcosis, in these cases, is frequently challenging, which, in most cases, requires histopathological examination. The authors report the case of a young female patient who presented a 20-day history of chest pleuritic pain and fever at the onset of symptoms. HIV serology was negative and CD4 count was normal. The imaging work-up was characterized by a huge opacity in the left inferior pulmonary lobe with a wide pleural base. Computed tomography showed a heterogeneous mass involving the bronchial tree. Mediastinal involvement was poor, and there was a splenomegaly. The patient underwent an exploratory thoracotomy and inferior lobectomy. The histopathological examination revealed a cryptococcoma. As the serum antigenemia was positive, the patient was scheduled for long-term treatment with fluconazole. The authors call attention to including the cryptococcal infection in the differential diagnosis of lung mass, mainly when localized in the lung bases in immunocompetent patients

Presentation of CMV immediate-early antigen to cytolytic T lymphocytes is selectively prevented by viral genes expressed in the early phase

The regulation of antigen processing and presentation to MHC class I-restricted cytolytic T lymphocytes was studied in cells infected with murine cytomegalovirus. Recognition by cytolytic T lymphocytes of the phosphoprotein pp89, the immunodominant viral antigen expressed in the immediate-early phase of infection, was selectively prevented during the subsequent expression of viral early genes. The surface expression of MHC class I glycoproteins and their capacity to present externally added pp89-derived antigenic peptides were not affected. Because recognition of several other antigens occurred during the early phase, a general failure in processing and presentation was excluded. Since neither rate of synthesis, amount, stability, nor nuclear transport of pp89 was modified, the failure in recognition indicates a selective interference with pp89 antigen processing and presentation

Endemic Plants: From Design to a New Way of Smart Hybrid Nanomaterials for Green Nanomedicine Applications

International audienc

Extractos de hojas de olivo de Chétoui: Influencia del tipo de disolventes sobre los compuestos fenólicos y su actividad antioxidante

The aim of this study was to investigate the influence of the solvent type on the extraction of phenolics and the antioxidant properties of the extracts obtained from Chétoui olive leaves. Extraction was conducted at room temperature using four solvents: deionized water (ddH2O), 80% methanol (80% MeOH), 70% ethanol (70% EtOH), and 80% acetone. Total phenols and total flavonoids were measured using the Folin-Ciocalteau and aluminum chloride colorimetric methods, respectively. The antioxidant properties have been determined by two scavenging activity methods, DPPH and ABTS. The total phenol and flavonoid contents of the olive leaf extracts (OLEs) ranged from 16.52 to 24.93 mg gallic acid g–1 DM and from 6.23 to 21.47 mg catechin g–1 DM, respectively. The IC50 values of DPPH varied from 0.17 to 0.97 mg mL–1 and the antioxidant activity values determined by ABTS (trolox equivalent antioxidant capacity) were between 629.87 and 1064.25 μmol TE g–1 DM. Our results revealed that extracting solvents have a significant influence on the antioxidant properties of olive leaves and that a methanol mixture is recommended for extracts with high levels of flavonoids and important antioxidant activities. Moreover, it was noticed that the trolox equivalent antioxidant capacity (TEAC) depends more on the flavonoids (r = 0.821) than on the total phenols (r = 0.399).El objetivo de este trabajo fue estudiar la influencia del disolvente usado en la extracción de los compuestos fenólicos y en las propiedades antioxidantes de los extractos obtenidos a partir de hojas de olivo procedente de la variedad Chétoui. La extracción se realizó a temperatura ambiente, usando cuatro disolventes: agua desionizada(ddH2O), metanol 80% (80% MeOH) , etanol 70% (70% EtOH), y acetona 80%. Los fenoles totales y los flavonoides totales se midieron usando los métodos colorimétricos con Folin-Ciocalteau y cloruro de aluminio, respectivamente. Las propiedades antioxidantes han sido determinadas por dos métodos: el DPPH y el ABTS. El contenido de fenoles totales y flavonoides de los extractos de hojas de olivo (OLEs) varió desde 16,52 hasta 24,93 mg de ácido gálico g–1 de materia seca y desde 6,23 hasta 21,47 mg de catequina g–1 de materia seca, respectivamente. Los valores de IC50 de DPPH varian de 0,17 a 0,97 mg mL–1 y los valores de la actividad antioxidante determinados por ABTS (capacidad antioxidante en equivalentes de trolox) se encuentran entre 629,87 y 1064,25 μmol TE g–1 de materia seca, respectivamente. Nuestros resultados revelaron que los disolventes de extracción tienen una influencia significativa en las propiedades antioxidantes de los extractos de hojas de oliva. El metanol se recomienda para los extractos con alto nivel de flavonoides y con actividades antioxidantes importantes. Además, se observó que la capacidad antioxidante en equivalente de trolox (TEAC) depende más de los flavonoides (r = 0,821) que de los fenoles totales (r = 0.399)

Características sensoriales de aceites de oliva virgen procedentes de cultivares tunecinos monovarietales e híbridos con variedades europeas

This paper describes a sensory analysis of olive oils from main Tunisian cultivars: Chemlali, Chétoui, Sradki, Sayali and Hor Kesra, and one Spanish cultivar: Arbequina. Some hybrids obtained from controlled crossings between Tunisian and European cultivars: Hd 031, Hd 034, Hd 038, Hd 039, Hd 044 & Hd 045, were also analysed. Sensory evaluation of oils was performed in order to evaluate their sensory profiles. A Duncan Test (a = 0,05) was applied using the data of each attribute and showed differences between analysed oils, pointing out the oil from the hybrids HD 044 for its bitter attribute. All collected data were also submitted to Cluster analysis, based on the similarity in Euclidian distances, showing the difference between the oil from hybrid HD 044 and the rest.Con el fin de definir su perfil organoléptico, se han evaluado sensorialmente seis aceites de oliva virgen procedentes de cinco cultivares establecidos en diferentes zonas de Túnez: Sayali, Sradki, Hor Kesra, Chétoui y Chemlali, y un cultivar de la provincia de Badajoz (España): Arbequina; así como los procedentes de seis cultivares híbridos igualmente establecidos en Túnez: Hd 031, Hd 034, Hd 038, Hd 039, Hd 044 y Hd 045. Un test de Duncan (a = 0,05), teniendo en cuenta las puntuaciones dadas a los diferentes atributos evaluados, permite observar diferencias entre los aceites estudiados, destacando la encontrada entre el aceite procedente del híbrido Hd 044 de los restantes por su nivel de amargo. Así mismo, un análisis de Cluster, muestra la similitud entre ellos, teniendo en cuenta esos mismos atributos, observándose una clara diferencia entre el aceite con origen en el híbrido Hd 044 y los restantes

Reproductive performance of native and imported dairy cows in the Tadla region (Morocco)

Parmi les performances de reproduction des vaches laitières dans la région du Tadla (Maroc) sur une période de 4 années, l’âge à la première insémination artificielle (IA) a été de 573,4 ± 35,6 jours et à l’âge au premier vêlage de 853,8 ± 103,5 jours, l’intervalle vêlage-1ère IA de 75,5 ± 35,6 jours. Celui-ci a été plus court chez les femelles importées que chez les natives. La race Montbéliarde a été inséminée plus tôt que la race Prim’Holstein. Le taux de réussite en 1ère IA a été de 53,2% avec de larges variations inter-annuelles et inter-élevages. Les Prim’holstein ont été mieux fécondées que les autres races. 18,2% des vaches ont nécessité 3 IA ou plus et l’indice coïtal a été de 1,8 ±1,3. La campagne, l’élevage et la race ont affecté significativement le taux de femelles ayant nécessité 3 IA ou plus. La race Prim’holstein française a manifesté un taux inférieur à celui de la race Prim’holstein canadienne. L’intervalle vêlage - insémination fécondante a été de 119,2 ± 83,8 jours. Ce paramètre a varié très significativement selon l’année, l’élevage, la race et le numéro de lactation. La race Montbéliarde a présenté undélai moyen de fécondation plus court que la race Prim’Holstein Canadienne