Diversity of cyanobacteria from thermal muds (Balaruc-Les-Bains, France) with the description of Pseudochroococcus coutei gen. nov., sp. nov.

Cyanobacteria are able to synthesize a high diversity of natural compounds that account for their success in the colonization of a variety of ecological niches. Many of them have beneficial properties. The mud from the thermal baths of Balaruc-Les-Bains, one of the oldest thermal baths in France, has long been recognized as a healing treatment for arthro-rheumatic diseases. To characterize the cyanobacteria living in these muds, several strains were isolated from the water column and biofilms of the retention basin and analyzed using a polyphasic approach. Morphological, ultrastructural and molecular (16S rRNA gene and 16S-23S ITS region sequencing) methods were employed to identify nine cyanobacterial strains belonging to the orders Chroococcales, Synechococcales, Oscillatoriales and Nostocales. The combination of morphological and genetic characteristics supported the description of a new genus and species with the type species as Pseudochroococcus coutei. The taxonomic diversity in the muds from Thermes de Balaruc-Les-Bains appears higher than previously documented, providing new candidate taxa for their observed therapeutic properties.

Transgenic expression of the human amphiregulin gene induces a psoriasis-like phenotype.

Amphiregulin (AR) is a heparin-binding, heparin-inhibited member of the epidermal growth factor (EGF) family and an autocrine growth factor for human keratinocytes. Previous studies have shown that AR expression is increased in psoriatic epidermis. To test the hypothesis that aberrant AR expression is central to the development of psoriatic lesions, we constructed a transgene (K14-ARGE) encoding a human keratin 14 promoter-driven AR gene. Our results indicate that transgene integration and subsequent expression of AR in basal keratinocytes correlated with a psoriasis-like skin phenotype. Afflicted mice demonstrated shortened life spans, prominent scaling and erythematous skin with alopecia, and occasional papillomatous epidermal growths. Histologic examination revealed extensive areas of marked hyperkeratosis with focal parakeratosis, acanthosis, dermal and epidermal lymphocytic and neutrophilic infiltration, and dilated blood vessels within the papillary dermis. Our results reveal that AR exerts activity in the skin that is distinct from that of transgenic transforming growth factor-alpha or other cytokines, and induces skin pathology with striking similarities to psoriasis. Our observations also link the keratinocyte EGF receptor-ligand system to psoriatic inflammation, and suggest that aberrant expression of AR in the epidermis may represent a critical step in the development or propagation of psoriatic lesions.

Stability of nicardipine hydrochloride in intravenous solutions.

The stability of nicardipine hydrochloride in large-volume i.v. solutions was studied. Admixtures of nicardipine hydrochloride 0.05 and 0.5 mg/mL were prepared in 5% dextrose and 0.45% sodium chloride injection, 5% dextrose and 0.9% sodium chloride injection, 0.45% sodium chloride injection, 0.9% sodium chloride injection, 5% dextrose and lactated Ringer's injection, 5% dextrose injection, lactated Ringer's injection, 5% sodium bicarbonate injection, and 5% dextrose injection with potassium chloride 40 meq/L. Two glass and two polyvinyl chloride (PVC) containers of each solution were prepared and stored at ambient room temperature under normal fluorescent light. Samples were removed and tested for nicardipine concentration by stability-indicating high-performance liquid chromatography at 0, 24, 48, and 72 hours and seven days. Testing included visual checking and optical density measurements. The admixtures remained clear and slightly yellow except for nicardipine hydrochloride in sodium bicarbonate injection, which showed immediate precipitation, and nicardipine hydrochloride in lactated Ringer's injection, which increased in optical density at 400 nm over time. There were no significant changes in nicardipine concentrations in nicardipine concentrations in glass containers. Admixtures stored in PVC containers showed a slow, constant decline in nicardipine concentrations, sometimes to less than 85% of the initial drug concentration within 24 hours, except for nicardipine hydrochloride in lactated Ringer's injection or 5% dextrose and lactated Ringer's injection, which showed an immediate and continuing rapid loss. Nicardipine hydrochloride 0.5 and 0.05 mg/mL in eight i.v. solutions was stable in glass containers for up to seven days. Drug concentrations slowly decreased in PVC containers. The drug was not stable in 5% sodium bicarbonate injection or in PVC bags containing lactated Ringer's injection or 5% dextrose and lactated Ringer's injection.