Blattabacteria, the endosymbionts of cockroaches, have small genome sizes and high genome copy numbers.

Blattabacteria are intracellular endosymbionts of cockroaches and primitive termites that belong to the class Flavobacteria and live only in specialized cells in the abdominal fat body of their hosts. In the present study we determined genome sizes as well as genome copy numbers for the endosymbionts of three cockroach species, Blattella germanica, Periplaneta americana and Blatta orientalis. The sole presence of blattabacteria in the fat body was demonstrated by rRNA-targeting techniques.

Identification of the weevil immune genes and their expression in the bacteriome tissue.

Background: Persistent infections with mutualistic intracellular bacteria (endosymbionts) are well represented in insects and are considered to be a driving force in evolution. However, while pathogenic relationships have been well studied over the last decades very little is known about the recognition of the endosymbionts by the host immune system and the mechanism that limits their infection to the bacteria-bearing host tissue (the bacteriome).

Results: To study bacteriome immune specificity, we first identified immune-relevant genes of the weevil Sitophilus zeamais by using suppressive subtractive hybridization (SSH) and then analyzed their full-length coding sequences obtained by RACE-PCR experiments.

Relationships of gag-pol diversity between Ty3/Gypsy and Retroviridae LTR retroelements and the three kings hypothesis.

Background: The origin of vertebrate retroviruses (Retroviridae) is yet to be thoroughly investigated, but due to their similarity and identical gag-pol (and env) genome structure, it is accepted that they evolve from Ty3/Gypsy LTR retroelements the retrotransposons and retroviruses of plants, fungi and animals. These 2 groups of LTR retroelements code for 3 proteins rarely studied due to the high variability - gag polyprotein, protease and GPY/F module. In relation to 3 previously proposed Retroviridae classes I, II and II, investigation of the above proteins conclusively uncovers important insights regarding the ancient history of Ty3/Gypsy and Retroviridae LTR retroelements.

Expanded criteria for liver transplantation in patients with cirrhosis and hepatocellular carcinoma.

Orthotopic liver transplantation (OLT) selection for patients with hepatocellular carcinoma (HCC) is a matter of debate. The Milan criteria (MC) have been largely adopted by the international community. The main aim of this study was to evaluate the survival rates and recurrence probabilities of a new proposal for criteria (up to 3 tumors, each no larger than 5 cm, and a cumulative tumor burden View Article and Find Full Text PDF

Evidence of recombination in intrapatient populations of hepatitis C virus.

Hepatitis C virus (HCV) is a major cause of liver disease worldwide and a potential cause of substantial morbidity and mortality in the future. HCV is characterized by a high level of genetic heterogeneity. Although homologous recombination has been demonstrated in many members of the family Flaviviridae, to which HCV belongs, there are only a few studies reporting recombination on natural populations of HCV, suggesting that these events are rare in vivo.

Specific expression of BMP2/4 ortholog in biomineralizing tissues of corals and action on mouse BMP receptor.

Bone morphogenetic proteins (BMPs) are members of the transforming growth factor beta superfamily, and have been identified by their ability to induce bone formation in vertebrates. The biomineral-forming process, called biomineralization, is a widespread process, present in all kingdoms of living organisms and among which stony corals are one of the major groups of calcifying animals. Here, we report the presence of a BMP2/4 ortholog in eight species of adult corals.

Genetic variability of hepatitis C virus before and after combined therapy of interferon plus ribavirin.

We present an analysis of the selective forces acting on two hepatitis C virus genome regions previously postulated to be involved in the viral response to combined antiviral therapy. One includes the three hypervariable regions in the envelope E2 glycoprotein, and the other encompasses the PKR binding domain and the V3 domain in the NS5A region. We used a cohort of 22 non-responder patients to combined therapy (interferon alpha-2a plus ribavirin) for which samples were obtained before initiation of therapy and after 6 or/and 12 months of treatment.

Massive presence of insertion sequences in the genome of SOPE, the primary endosymbiont of the rice weevil Sitophilus oryzae.

Bacteria that establish an obligate intracellular relationship with eukaryotic hosts undergo an evolutionary genomic reductive process. Recent studies have shown an increase in the number of mobile elements in the first stage of the adaptive process towards intracellular life, although these elements are absent in ancient endosymbionts. Here, the genome of SOPE, the obligate mutualistic endosymbiont of rice weevils, was used as a model to analyze the initial events that occur after symbiotic integration.

Mapping natural polymorphisms of hepatitis C virus NS3/4A protease and antiviral resistance to inhibitors in worldwide isolates.

Background: Several inhibitors for the hepatitis C virus (HCV) NS3/4A protease are under development. Although previous studies identified viral resistance mutations, there is little information on the natural variability of proteases from the different viral subtypes. Here, we aimed to determine both the natural variability and presence of resistance or compensatory mutations to new protease inhibitors (PI) in NS3/4A proteases from worldwide HCV isolates.

Metagenomics reveals our incomplete knowledge of global diversity.

Javier.tamames@uv.es

Early progress in aphid genomics and consequences for plant-aphid interactions studies.

Aphids occupy a niche comprising two conceptual realms: a micron-scale feeding site beneath the plant surface, in which a syringe-like appendage mediates chemical exchange with a specific plant cell type; and the larger realm of a metazoan with sensory organs, a nervous system, and behavior, all responsive to the condition of the host plant and the broader environment. The biology that connects these realms is not well understood, but new details are emerging with the help of genomic tools. The power of these tools is set to increase substantially now that the first genome of an aphid is being sequenced and annotated.

Carbonic anhydrase in the scleractinian coral Stylophora pistillata: characterization, localization, and role in biomineralization.

Carbonic anhydrases (CA) play an important role in biomineralization from invertebrates to vertebrates. Previous experiments have investigated the role of CA in coral calcification, mainly by pharmacological approaches. This study reports the molecular cloning, sequencing, and immunolocalization of a CA isolated from the scleractinian coral Stylophora pistillata, named STPCA.

Calcification and associated physiological parameters during a stress event in the scleractinian coral Stylophora pistillata.

High calcification rates observed in reef coral organisms are due to the symbiotic relationship established between scleractinian corals and their photosynthetic dinoflagellates, commonly called zooxanthellae. Zooxanthellae are known to enhance calcification in the light, a process referred as "light-enhanced calcification". The disruption of the relationship between corals and their zooxanthellae leads to bleaching.

The striking case of tryptophan provision in the cedar aphid Cinara cedri.

Buchnera aphidicola BCc has lost its symbiotic role as the tryptophan supplier to the aphid Cinara cedri. We report the presence of a plasmid in this endosymbiont that contains the trpEG genes. The remaining genes for the pathway (trpDCBA) are located on the chromosome of the secondary endosymbiont "Candidatus Serratia symbiotica.

[Clinical characteristics of patients with persistent atrial fibrillation referred for cardioversion: Spanish Cardioversion Registry (REVERSE)].

The objectives were to investigate the treatment and clinical characteristics of patients referred for cardioversion in Spain and to compare them with those reported in the AFFIRM (Atrial Fibrillation Follow-up Investigation of Rhythm Management) and RACE (RAte Control versus Electrical cardioversion) studies. The prospective study involved 1515 consecutive patients with persistent atrial fibrillation who were referred for cardioversion at 96 Spanish hospitals. Half of the patients were being treated with Vaughan-Williams group-I or -III antiarrhythmic drugs.

Enhanced adaptation of vesicular stomatitis virus in cells infected with vaccinia virus.

Infections involving different viruses (multiple infections) are common in nature and can take place between different strains of the same virus or between different virus species, including DNA and RNA viruses. The influence of multiple infections on viral evolution has been previously studied using different populations of the same virus. Here, we took a step forward by studying the evolution of an RNA virus (vesicular stomatitis virus, VSV) in the presence of a resident DNA virus (vaccinia virus, VV).

Evolution of the secondary symbiont "Candidatus serratia symbiotica" in aphid species of the subfamily lachninae.

Buchnera aphidicola BCc, the primary endosymbiont of the aphid Cinara cedri (subfamily Lachninae), is losing its symbiotic capacity and might be replaced by the coresident "Candidatus Serratia symbiotica." Phylogenetic and morphological analyses within the subfamily Lachninae indicate two different "Ca. Serratia symbiotica" lineages and support the longtime coevolution of both symbionts in C.

Refined analysis of genetic variability parameters in hepatitis C virus and the ability to predict antiviral treatment response.

Hepatitis C virus (HCV) infects approximately 3% of the world population. The chronicity of hepatitis C seems to depend on the level of genetic variability. We have recently (Torres-Puente et al.

Mutational events in cefotaximase extended-spectrum beta-lactamases of the CTX-M-1 cluster involved in ceftazidime resistance.

CTX-M beta-lactamases, which show a high cefotaxime hydrolytic activity, constitute the most prevalent extended-spectrum beta-lactamase (ESBL) type found among clinical isolates. The recent explosive diversification of CTX-M enzymes seems to have taken place due to the appearance of more efficient enzymes which are capable of hydrolyzing both cefotaxime and ceftazidime, especially among the CTX-M-1 cluster. A combined strategy of in vitro stepwise evolution experiments using bla(CTX-M-1), bla(CTX-M-3), and bla(CTX-M-10) genes and site-directed mutagenesis has been used to evaluate the role of ceftazidime and other beta-lactam antibiotics in triggering the diversity found among enzymes belonging to this cluster.

Cloning and use of a coral 36B4 gene to study the differential expression of coral genes between light and dark conditions.

This paper aims to validate reference genes for gene expression studies between light and dark conditions in the scleractinian coral Stylophora pistillata for future gene expression studies of the "light-enhanced calcification" phenomenon. For this purpose, we cloned, sequenced, and characterized a candidate reference gene, the 36B4 gene from the coral S. pistillata, and validated 36B4 and beta-actin as reference genes.

Improved arrhythmia detection in implantable loop recorders.

Introduction: Implantable loop recorders (ILR) have an automatic arrhythmia detection feature that can be compromised by inappropriately detected episodes. This study evaluated a new ILR sensing and detection scheme for automatically detecting asystole, bradyarrhythmia, and tachyarrhythmia events, which is implemented in the next generation device (Reveal DX/XT).

Methods And Results: The new scheme employs an automatically adjusting R-wave sensing threshold, enhanced noise rejection, and algorithms to detect asystole, bradyarrhythmia, and tachyarrhythmia.

Estimating the extent of horizontal gene transfer in metagenomic sequences.

Background: Although the extent of horizontal gene transfer (HGT) in complete genomes has been widely studied, its influence in the evolution of natural communities of prokaryotes remains unknown. The availability of metagenomic sequences allows us to address the study of global patterns of prokaryotic evolution in samples from natural communities. However, the methods that have been commonly used for the study of HGT are not suitable for metagenomic samples.

Shift- and scale-invariant recognition of contour objects with logarithmic radial harmonic filters.

The phase-only logarithmic radial harmonic (LRH) filter has been shown to be suitable for scale-invariant block object recognition. However, an important set of objects is the collection of contour functions that results from a digital edge extraction of the original block objects. These contour functions have a constant width that is independent of the scale of the original object.

Fermentation of acid hydrolysates from olive-tree pruning debris by Pachysolen tannophilus.

The influence of the type and concentration of acid in the hydrolysis process and its effect on the subsequent fermentation by Pachysolen tannophilus (ATCC 32691) to produce ethanol and xylitol was studied. The hydrolysis experiments were performed using hydrochloric, sulphuric and trifluoroacetic acids in concentrations ranging from 0.1 to 1.

Learning how to live together: genomic insights into prokaryote-animal symbioses.

Our understanding of prokaryote-eukaryote symbioses as a source of evolutionary innovation has been rapidly increased by the advent of genomics, which has made possible the biological study of uncultivable endosymbionts. Genomics is allowing the dissection of the evolutionary process that starts with host invasion then progresses from facultative to obligate symbiosis and ends with replacement by, or coexistence with, new symbionts. Moreover, genomics has provided important clues on the mechanisms driving the genome-reduction process, the functions that are retained by the endosymbionts, the role of the host, and the factors that might determine whether the association will become parasitic or mutualistic.