Streptococcus halichoeri sp nov., isolated from grey seals (Halichoerus grypus)

Phenotypic and phylogenetic studies were performed on six unidentified, Gram-positive, catalase-negative, chain-forming Streptococcus-like organisms recovered from grey seals. Biochemically the six strains were highly related to each other, but they did not appear to correspond to any recognized species of the genus Streptococcus. Comparative 16S rRNA gene sequencing studies confirmed that phylogenetically the strains were members of the genus Streptococcus, but sequence divergence values of greater than 3 % compared with reference streptococcal species demonstrated that the organisms from seals represent a novel species. SDS-PAGE analysis of whole-cell proteins confirmed the phenotypic distinctiveness of the seal organisms. Based on biochemical criteria and molecular chemical and genetic evidence, it is proposed that the unknown organism from seals be classified as a novel species, Streptococcus halichoeri sp. nov., the type strain of which is CCUG 48324(T) (=CIP 108195(T)).

Streptococcus marimammalium sp nov., isolated from seals

Two strains of an unidentified, Gram-positive, catalase-negative, chain-forming, coccus-shaped organism recovered from seals were characterized using phenotypic and molecular taxonomic methods. Based on morphological and biochemical criteria the strains were tentatively identified as streptococci but they did not appear to correspond to any recognized species of the genus Streptococcus. Comparative 16S rRNA gene sequencing studies showed that the strains were closely related to each other and confirmed their placement in the genus Streptococcus. Sequence divergence values of > 5 % with reference streptococcal species demonstrated the organisms from seals represent a novel species. SDS-PAGE analysis of whole-cell proteins confirmed that the two organisms were closely related to each other but were different from all currently defined streptococcal species. Based on biochemical criteria, molecular chemical and molecular genetic evidence, it is proposed that the unknown isolates from seals be assigned to a novel species of the genus Streptococcus, Streptococcus marimammalium sp. nov. The type strain is M54/01/(T) (=CCUG 48494(T)=CIP 108309(T)).

The PML for rough surface scattering

In this paper we investigate the use of the perfectly matched layer (PML) to truncate a time harmonic rough surface scattering problem in the direction away from the scatterer. We prove existence and uniqueness of the solution of the truncated problem as well as an error estimate depending on the thickness and composition of the layer. This global error estimate predicts a linear rate of convergence (under some conditions on the relative size of the real and imaginary parts of the PML function) rather than the usual exponential rate. We then consider scattering by a half-space and show that the solution of the PML truncated problem converges globally at most quadratically (up to logarithmic factors), providing support for our general theory. However we also prove exponential convergence on compact subsets. We continue by proposing an iterative correction method for the PML truncated problem and, using our estimate for the PML approximation, prove convergence of this method. Finally we provide some numerical results in 2D.(C) 2008 IMACS. Published by Elsevier B.V. All rights reserved.

Quality of medicines stored together in multi-compartment compliance aids

Background and Objective: Dispensing medicines into compliance aids is a common practice in pharmacy contrary to manufacturers’ advice and studies have shown the appearance of light-sensitive tablets is compromised by such storage; we previously found evidence of reduced bioavailability at elevated temperature and humidity. Our objective was to examine the physicochemical stability of two generic atenolol tablets in different compliance aids and with aspirin co-storage at room temperature and at 40 °C/75% relative humidity. Methods: The physicochemical stability of atenolol tablets was evaluated after 28 days of storage and compared with controls by examining visual appearance, weight, disintegration, dissolution, friability and hardness to accepted standards and using a previously validated HPLC method for chemical assay. Results and Discussion: The response to storage was brand-dependent and not straightforward. With one make of atenolol (Alpharma), storage in compliance aids even at room temperature impacted on physical stability, reducing tablet hardness, with storage in Dosett® exerting a greater impact than storage in Medidos® (t-test P < 0·001). Co-storage at elevated temperature and humidity also impacted on the appearance of non-coated aspirin tablets (Angette™). The chemical stability of atenolol was not affected and we did not find evidence of changes to bioavailability with either make. Certainly data for one atenolol make (CP Pharmaceuticals) co-stored with aspirin (Angette™ and Nu-Seals) in both compliance aids at room temperature provided evidence of short-term stability. But medicines are dispensed into compliance aids in multi-factorial ways so our study highlights not only the lack of evidence but also a realization that evidence to support real practice may not be accomplished through research. Conclusion: Reassuring practitioners of the continued stability of medicines in compliance aids under the countless condition in which they are dispensed in practice may requires a different approach involving medical device regulators and more definitive professional guidance.

Campylobacter insulaenigrae sp nov., isolated from marine mammals

Phenotypic and phylogenetic studies were performed on four Campylobacter-like organisms recovered from three seals and a porpoise. Comparative 16S rRNA gene sequencing studies demonstrated that the organisms represent a hitherto unknown subline within the genus Campylobacter, associated with a subcluster containing Campylobacter jejuni, Campylobacter coli and Campylobacter lari. DNA-DNA hybridization studies confirmed that the bacteria belonged to a single species, for which the name Campylobacter insulaenigrae sp. nov. is proposed. The type strain of Campylobacter insulaenigrae sp. nov. is NCTC 12927(T) (= CCUG 48653(T)).

Arthrobacter nasiphocae sp. nov., from the common seal (Phoca vitulina)

An unknown gram-positive, catalase-positive, strictly aerobic, rod-shaped bacterium was isolated from the nasal cavities of two common seals. Chemical analysis revealed the presence in the bacterium of a hitherto unknown cell-wall murein [type: L-Lys-L-Ala2-Gly(2-3)-L-Ala (Gly)]. Comparative 16S rRNA gene sequencing showed that the unidentified rod was related to the Arthrobacter group of organisms, although sequence divergence values of >3% from established members of this genus indicated that it represents a novel species. On the basis of phenotypic and phylogenetic considerations, it is proposed that the unknown bacterium from seals (Phoca vitulina) be classified as a novel species, Arthrobacter nasiphocae sp. nov. The type strain of Arthrobacter nasiphocae is CCUG 42953T.

Actinomyces marimammalium sp. nov., from marine mammals

Three strains of a previously undescribed Actinomyces-like bacterium were isolated from samples taken from two dead seals and a porpoise. Biochemical testing and PAGE analysis of whole-cell proteins indicated the strains were phenotypically similar to each other but different from previously described Actinomyces and Arcanobacterium species. Comparative 16S rRNA gene sequencing studies showed the organisms from marine animals were genetically closely related and represent a hitherto unknown subline within the genus Actinomyces (sequence divergence values > 6% with recognized species). Based on phylogenetic and phenotypic evidence it is proposed that the unknown bacterium from the seals and a porpoise should be classified as Actinomyces marimammalium sp. nov. The type strain is CCUG 41710T.