Limitations of amebocyte lysate test for endotoxin control in raw materials for liposomal nanoformulations.

To evaluate the applicability of amebocyte lysate (LAL) assay for endotoxin determination in lipid compounding liposomal nanoformulations. Spiked cholesterol, hydrogenated soy phosphatidylcholine and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (DSPE-PEG 2000) samples with endotoxins, simulating contaminated samples or in-process contamination were analyzed by chromogenic LAL assay. Recovery of spiked endotoxins was achieved from DSPE-PEG 2000 suspended in water, whereas recovery was not achieved from spiked cholesterol and hydrogenated soy phosphatidylcholine suspended in methanol, and from multilamellar vesicles.

New insights into the antiviral activity of nordihydroguaiaretic acid: Inhibition of dengue virus serotype 1 replication.

Background: Dengue virus (DENV) is considered one of the most important pathogens in the world causing 390 million infections each year. Currently, the development of vaccines against DENV presents some shortcomings and there is no antiviral therapy available for its infection. An important challenge is that both treatments and vaccines must be effective against all four DENV serotypes.

"On-Demand" Antimicrobial Photodynamic Activity through Supramolecular Photosensitizers Built with Rose Bengal and (Vinylbenzyl)triethylammomium Polycation Derivatives.

The antimicrobial photodynamic activity (aPDA) in fungal and bacterial strains of supramolecular adducts formed between the anionic photosensitizer (PS) Rose Bengal (RB) and aromatic polycations derived from (-vinylbenzyl)triethylammonium chloride was evaluated. Stable supramolecular adducts with dissociation constants ≈ 5 μM showed photosensitizing properties suitable for generating singlet oxygen (Φ = 0.5 ± 0.

Photosensitization of a subcutaneous tumour by the natural anthraquinone parietin and blue light.

Photodynamic therapy (PDT) is an anticancer treatment involving administration of a tumour-localizing photosensitizer, followed by activation by light of a suitable wavelength. In previous work, we showed that the natural anthraquinone (AQ) Parietin (PTN), was a promising photosensitizer for photodynamic therapy of leukemic cells in vitro. The present work aimed to analyze the photosensitizing ability of PTN in the mammary carcinoma LM2 cells in vitro and in vivo in a model of subcutaneously implanted tumours.

Inactivation of Herpes Simplex Virus by Photosensitizing Anthraquinones Isolated from Heterophyllaea pustulata.

is a phototoxic plant from Argentina. Aerial parts extracts, high in photosensitizing anthraquinones, have shown antiviral activity. The purpose of this study was to study the antiherpetic activity of the main purified anthraquinones, even evaluating their competence as photodynamic sensitizers to photo-stimulate the antiviral effect.

First report of antiviral activity of nordihydroguaiaretic acid against Fort Sherman virus (Orthobunyavirus).

The genus Orthobunyavirus are a group of viruses within arbovirus, with a zoonotic cycle, some of which could lead to human infection. A characteristic of these viruses is their lack of antiviral treatment or vaccine for its prevention. The objective of this work was to study the in vitro antiviral activity of nordihydroguaiaretic acid (NDGA), the most important active compound of Larrea divaricata Cav.

Photodynamic therapy of tumour cells mediated by the natural anthraquinone parietin and blue light.

Photodynamic therapy (PDT) is a treatment for superficial tumours involving the administration of a photosensitiser followed by irradiation. The potential of the natural anthraquinone parietin (PTN) in PDT is still relatively unexploited. In the present work, PTN isolated from the lichen Teoloschistes nodulifer (Nyl.

Experimental poisoning by Heterophyllaea pustulata Hook. f. (Rubiaceae) in goats. Clinical, biochemical and toxicological aspects.

The aim of this study was to investigate the clinical, biochemical and toxicological findings of the experimentally poisoning induced by Heterophyllaea pustulata in goats. Ten healthy adult female Saanen breed goats were used in the experiment. The goats were randomly assigned to two groups of five individuals: control and experimental group (CG and EG).

On the mechanism of Candida tropicalis biofilm reduction by the combined action of naturally-occurring anthraquinones and blue light.

The photoprocesses involved in the photo-induced Candida tropicalis biofilm reduction by two natural anthraquinones (AQs), rubiadin (1) and rubiadin-1-methyl ether (2), were examined. Production of singlet oxygen (1O2) and of superoxide radical anion (O2•-) was studied. Although it was not possible to detect the triplet state absorption of any AQs in biofilms, observation of 1O2 phosphorescence incubated with deuterated Phosphate Buffer Solution, indicated that this species is actually formed in biofilms.

The anthraquinones rubiadin and its 1-methyl ether isolated from Heterophyllaea pustulata reduces Candida tropicalis biofilms formation.

Background: Candida tropicalis is increasingly becoming among the most commonly isolated pathogens causing fungal infections with an important biofilm-forming capacity.

Purpose: This study addresses the antifungal effect of rubiadin (AQ1) and rubiadin 1-methyl ether (AQ2), two photosensitizing anthraquinones (AQs) isolated from Heterophyllaea pustulata, against C. tropicalis biofilms, by studying the cellular stress and antioxidant response in two experimental conditions: darkness and irradiation.

Reduction of Candida tropicalis biofilm by photoactivation of a Heterophyllaea pustulata extract.

Context: Biofilm formation is an important problem, since this growth mode confers resistance to drugs usually used in therapeutics.

Objective: In vitro antifungal activity of extracts obtained from Heterophyllaea pustulata Hook f. (Rubiaceae) were studied against Candida tropicalis biofilms, evaluating the effect of irradiation and the oxidative and nitrosative stresses as possible mechanisms of action.

In vitro antiviral activity of Heterophyllaea pustulata extracts.

The antiviral activity was tested of different polarity extracts, with differing chemical composition, obtained from aerial parts of Heterophyllaea pustulata Hook f. (Rubiaceae) against Herpes Simplex Virus Type I (HSV-1) and Saint Louis Encephalitis Virus (SLEV). The Vero cell line was employed as a host cell for the antiviral assessment of benzene (Ben), ethyl acetate (EtOAc) and ethanol (EtOH) extracts by means of the Neutral Red uptake assay and plaque reduction test.