Immunocytochemical analysis of the stage-specific distribution of collagen in the cuticle of Meloidogyne incognita

Il a été porduit un antisérum polyclonal dirigé contre la protéine majeure du collagène (76 kDa) extraite de la cuticule de femelles adultes de #Meloidogyne incognita. La composition en acides aminés de cette protéine est semblable à celle du collagène d'autres nématodes. Parmi les protéines extraites de la cuticule de femelles adultes de #Meloidogyne et solubles dans le bêta-mercaptoéthanol, deux protéines du collagène (Mr 76 et 140 kDa) ainsi que plusieurs protéines du collagène de junéviles de deuxième stade (J2), réagissent au cours d'analyse Western blot avec des anticorps polyclonaux. L'antisérum polyclonal a été utilisé en microscopie électronique pour localiser le collagène dans la cuticule de différents stades et dans la paroi de l'oeuf. Chez les J2 libres et les adultes mâles, où la cuticule est formée de trois couches distinctes, un marquage, intense, par l'or ne concerne que la couche corticale, et non l'épicuticule, la couche médiane ou la couche basale striée. Chez les J2 sédentaires enflés, dont la cuticule est de structure homogène, les particules d'or sont réparties dans toute la profondeur de la cuticule. Les particules d'or sont également uniformément réparties dans toute l'épaisseur de la cuticule des femelles adultes, y compris après purification au SDS. Dans la paroi de l'oeuf, le marquage à l'or est visible à la surface de la couche chitineuse. (Résumé d'auteur

Extracellular aspartic protease SAP2 of Candida albicans yeast cleaves human kininogens and releases proinflammatory peptides, Met-Lys-bradykinin and des-Arg(9)-Met-Lys-bradykinin

Bradykinin-related peptides, universal mediators of inflammation collectively referred to as the kinins, are often produced in excessive amounts during microbial infections. We have recently shown that the yeast Candida albicans, the major fungal pathogen to humans, can exploit two mechanisms to enhance kinin levels at the sites of candidial infection, one depending on adsorption and activation of the endogenous kinin-generating system of the host on the fungal cell wall and the other relying on cleavage of kinin precursors, the kininogens, by pathogen-secreted proteases. This work aimed at assigning this kininogenase activity to the major secreted aspartic protease of C. albicans (SAP2). The purified SAP2 was shown to cleave human kininogens, preferably the low molecular mass form (LK) and optimally in an acidic environment (pH 3.5-4.0), and to produce two kinins, Met-Lys-bradykinin and its derivative, {[}Hydroxyproline(3)]-Met-Lys-bradykinin, both of which are capable of interacting with cellular bradykinin receptors of the B2 subtype. Additionally, albeit with a lower yield, des-Arg(9)-Met-Lys-bradykinin, an effective agonist of B1-subtype receptors, was released. The pathophysiological potential of these kinins and des-Arg-kinin was also proven by presenting their ability to stimulate human promonocytic cells U937 to release proinflammatory interleukin 1 beta (IL-1 beta) and IL-6

FORMULATION AND EVALUATION OF TROPICAMIDE IN-SITU GELS LOADED SOLID LIPID NANOPARTICLES FOR OCULAR DRUG DELIVERY

The aim of present work Formulation and Evaluation of Tropicamide In-situ Gels loaded Solid Lipid Nanoparticles for Ocular Drug Delivery. The surface morphological of SLN was carried out by TEM. The Tropicamide loaded solid lipid nanoparticles was measured the average particle size was ranges from 182.1+3.12nm to 390.1±2.10 nm. The zeta potential ranges from -0.17±1.4 mV to -3.80±1.5 mV. The entrapment efficiency 66.2 % to 89.2 %. Drug content was ranges from 0.112mg/ml to 0.502 mg/ml. The percentage yield ranges from was ranges from 0.112mg/ml to 0.502 mg/ml. The polydispersity index ranged from 1.011±0.15 to 1.327±0.13. These SLN enriched in Chitosan gels the pH of the formulations range from 6.8 to 6.9. The gelling strength ranged from 129 sec to 152 sec. The bioadhesive force was ranges from 10.21 ±1.15 dynes/cm2 to 15.23 ± 1.22 dynes/cm2. The viscosity was ranges from 2212 ± 1.14 cps to 2420± 1.19 cps. The spreadability coefficient was ranges from 11.2 ± 1.10 gms/sec to 13.3 ± 1.21 gms/sec. The in-vitro diffusion release studies carried out at 12 hrs TSLNGF19 shows the 79.2 ± 0.32. The ex vivo permeation studies for optimized formulation the increased drug permeation and corneal accumulation. In vitro corneal permeation profile of tropicamide loaded SLN from the chitosan gels and commercial eye drop solution (Tropicacyl) across the isolated porcine cornea. The ocular tolerance studies performed with HETCAM assay, corneal hydration study, histopathological studies. The stability studies of chitosan gels for long-term stability as per ICH guidelines (25°C ± 2°C / 60% RH ± 5% RH) &accelerated stability as per ICH guidelines (40°C ± 2°C / 75% RH ± 5% RH) there is no changes in gelling strength, bioadhesive force, viscosity, spreadability coefficient in optimized formulation. Keywords: Chitosan, Corneal hydration studies, ex vivo permeation, in vitro diffusion studies, Solid Lipid Nanoparticle

A NOVEL APPROACHES ON OCULAR DRUG DELIVERY SYSTEM

The purpose of this review is giving a current update of the knowledge in this field of ocular drug delivery. The ocular drug delivery has been a major challenge to drug delivery scientists mainly due to its unique anatomy and physiology. One of the major problems encountered by the conventional ocular dosage forms include the rapid precorneal drug loss due to its nasolacrimal drainage, tear turnover and drug dilution resulting in poor bioavailability. These efforts lead to development of novel drug delivery dosage forms such as nanoparticles, liposome, ocuserts, and mucoadhesive formulations. Controlled drug delivery systems offer many advantages over conventional dosage forms in terms of improving drug bioavailability, reducing toxicity and decreasing dosage frequency. Designing noninvasive sustained drug delivery systems and exploring the feasibility of topical application to deliver drugs to the posterior segment may drastically improve drug delivery in the years to come. Keywords: Ocular drug delivery, Eye, Conventional drug delivery, novel dosage forms, approaches.Â

Modulation of the cell membrane expression of the kininogens regulates the rate of bradykinin delivery to cells

The kininogens were first recognized as the parent molecules for bradykinin. Their relative physiologic importance in plasma hemostasis and fibrinolysis and tissue cysteine protease inhibition has not been clarifed. Recent studies on the structure and function of the plasma kininogens, their interaction with cells of the intravascular compartment, and clinical investigations on contact system activation have refocused the physiologic importance of these proteins to kinin delivery for the maintance of vasodilatory tone. Kininogen expression on platelets slows the rate of kinin liberation, and kinins upregulate kininogen expression on endothelial cells. Regulation of kinin delivery by influencing kininogen expression may provide for new agents to manipulate blood pressure.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/30063/1/0000433.pd