Occurrence and characterisation of intervening sequences (IVSs) within 16S rRNA genes from two atypical Campylobacter species, C. sputorum and C. curvus

Internal sample process control improves cultivation-independent quantification of thermotolerant Campylobacter

Quantification of Campylobacter is challenging and one major reason is the fact that bacteria lose cultivability due to cold or oxygen stress during storage at retail. Alternative live/dead discriminatory qPCR currently lacks standardization and might overestimate live cells in the presence of dead cells. In this study an internal sample process control (ISPC) was developed. The ISPC consists of a specified number of peroxide-killed C. sputorum cells to be added to each sample in order to monitor (i) the level of reduction of the signal from dead cells and (ii) DNA losses during sample processing. A species-specific fragment of the 16S rRNA gene of C. sputorum was selected as real-time PCR target, based on its similar size and gene copy number compared to the C. jejuni/coli/lari target and confirmed in an exclusivity study. Extension of the amplification oligonucleotides for the target of thermotolerant Campylobacter improved real-time PCR efficiency, rendering the method suitable for quantification according to international standards. Concordant PCR signal variation of both C. jejuni and C. sputorum targets in co-inoculated chicken rinses verified the suitability of the ISPC. This provides a crucial step towards implementation of cultivation-independent quantification for improved food safety of fastidious bacteria.

[The forensic medical evaluation of traumatic and spontaneous ruptures of the organs affected by the tumours]

The present article was designed to report the results of the analysis of the cases of traumatic and spontaneous ruptures of the organs affected by the tumours based on the original observations and the literature data. It is shown that the probability of the tumour rupture depends on its histological type, localization, the size, and the distance from the capsule of the affected organ, the degree of involvement of the major blood vessels, the severity of the necrotic changes, the presence of cysts in the neoplasm, and the regimens of radio- and chemotherapy. Moreover, the rupture can be facilitated by anticoagulation therapy, intake or oral contraceptives, pregnancy, concomitant diseases, alcoholic intoxication, splenomegaly, and hypocoagulation resulting from dissemination of the neoplastic process or the metastatic lesions of the liver. Even a minimal injury to the skin can provoke the tumour rupture associated with the fatal hemorrhage. A delayed rupture within a few hours or days is possible.

Hippea jasoniae sp. nov. and Hippea alviniae sp. nov., thermoacidophilic members of the class Deltaproteobacteria isolated from deep-sea hydrothermal vent deposits

Thirteen novel, obligately anaerobic, thermoacidophilic bacteria were isolated from deep-sea hydrothermal vent sites. Four of the strains, designated EP5-r(T), KM1, Mar08-272r(T) and Mar08-368r, were selected for metabolic and physiological characterization. With the exception of strain EP5-r(T), all strains were short rods that grew between 40 and 72 °C, with optimal growth at 60-65 °C. Strain EP5-r(T) was more ovoid in shape and grew between 45 and 75 °C, with optimum growth at 60 °C. The pH range for growth of all the isolates was between pH 3.5 and 5.5 (optimum pH 4.5 to 5.0). Strain Mar08-272r(T) could only grow up to pH 5.0. Elemental sulfur was required for heterotrophic growth on acetate, succinate, Casamino acids and yeast extract. Strains EP5-r(T), Mar08-272r(T) and Mar08-368r could also use fumarate, while strains EP5-r(T), KM1 and Mar08-272r(T) could also use propionate. All isolates were able to grow chemolithotrophically on H(2), CO(2), sulfur and vitamins. Phylogenetic analysis of 16S rRNA gene sequences placed all isolates within the family Desulfurellaceae of the class Deltaproteobacteria, with the closest cultured relative being Hippea maritima MH(2)(T) (~95-98 % gene sequence similarity). Phylogenetic analysis also identified several isolates with at least one intervening sequence within the 16S rRNA gene. The genomic DNA G+C contents of strains EP5-r(T), KM1, Mar08-272r(T) and Mar08-368r were 37.1, 42.0, 35.6 and 37.9 mol%, respectively. The new isolates differed most significantly from H. maritima MH(2)(T) in their phylogenetic placement and in that they were obligate thermoacidophiles. Based on these phylogenetic and phenotypic properties, the following two novel species are proposed: Hippea jasoniae sp. nov. (type strain Mar08-272r(T) = DSM 24585(T) = OCM 985(T)) and Hippea alviniae sp. nov. (type strain EP5-r(T) = DSM 24586(T) = OCM 986(T)).