Molecular phylogeny of French Guiana Hylinae: implications for the systematic and biodiversity of the Neotropical frogs.

In this study we used nucleotide sequences from a segment of mitochondrial 16S ribosomal DNA gene to investigate the evolutionary relationships of some French Guiana Hylinae. New sequences, representing the members of different French Guiana frogs-five specimens of the Scinax genus, two Hyla, one Osteocephalus, one Hyalinobatrachium and two Rana as out-group-were examined. In addition, 26 sequences available from GenBank database representing the other subfamilies of the Hylidae were added to our study.

Evidence of en bloc duplication in vertebrate genomes.

It has been 30 years since it was first proposed that the vertebrate genome evolved through several rounds of genome-wide duplications (polyploidizations). Despite rapid advances in genetics, including sequencing of the complete genomes of several divergent species, this hypothesis has not been tested rigorously and is still a matter of debate. If polyploidizations occurred during chordate evolution, there should be a network of paralogous regions in the present-day jawed vertebrate (Gnathostomata) genomes.

Cutting edge: recruitment of the ancestral fyn gene during emergence of the adaptive immune system.

The adaptive immune system (AIS) is characterized by the MHC molecules and the rearranging Ag receptors, and was established in a common ancestor of jawed vertebrates. Fyn, a Src-family tyrosine kinases, is important for normal development and function of T lymphocytes and neuronal cells. Indeed, as the result of an alternative splicing of a distinct exon 7, fyn encodes for two isoforms, FynT in T lymphocytes and FynB in the brain.

Sugar specificity of bacterial CMP kinases as revealed by crystal structures and mutagenesis of Escherichia coli enzyme.

Bacterial cytidine monophosphate (CMP) kinases are characterised by an insert enlarging their CMP binding domain, and by their particular substrate specificity. Thus, both CMP and 2'-deoxy-CMP (dCMP) are good phosphate acceptors for the CMP kinase from Escherichia coli (E. coli CMPK), whereas eukaryotic UMP/CMP kinases phosphorylate the deoxynucleotides with very low efficiency.

Living-related liver transplantation and vena cava reconstruction after total hepatectomy including the vena cava for hepatoblastoma.

Background: In most cases of total hepatectomy (TH) required for hepatoblastoma (HB), the retrohepatic inferior vena cava (IVC) has to be removed with the native liver for complete tumor excision. Because the liver graft procured by living donation has no IVC, a reconstruction of the recipient IVC is needed. We report our experience with living-related liver transplantation (LRLT) and IVC replacement in such cases.

[Peripartum cardiomyopathy].

Peripartum cardiomyopathy is a rare, potentially life-threatening cardiomyopathy of unknown cause. Diagnosis includes clinical (development of cardiac failure in the last month of pregnancy or within 5 months after delivery, absence of an identifiable cause of cardiac failure and absence of recognizable heart disease prior to the last month of pregnancy) and echographic (left ventricular systolic dysfunction) criteria. Therapy is standard, except for angiotensin converting enzyme inhibitors, which should be avoided at the end of pregnancy, and heart transplantation if medical treatment fails.

X-ray structure of TMP kinase from Mycobacterium tuberculosis complexed with TMP at 1.95 A resolution.

The X-ray structure of Mycobacterium tuberculosis TMP kinase at 1.95 A resolution is described as a binary complex with its natural substrate TMP. Its main features involve: (i) a clear magnesium-binding site; (ii) an alpha-helical conformation for the so-called LID region; and (iii) a high density of positive charges in the active site.

Mitochondrial DNA sequence diversity in two groups of Italian Veneto speakers from Veneto.

Although frequencies of mitochondrial DNA (mtDNA) haplogroups in the different European populations are rather homogenous, there are a few European populations or linguistic isolates that show different mtDNA haplogroup distributions; examples are the Saami and Ladin speakers from the eastern Italian Alps. MtDNA sequence diversity was analysed from subjects from two villages in Veneto. The first, Posina, is situated in the Venetian Alps near Vicenza.

Partial combination applied to phylogeny of European cyprinids using the mitochondrial control region.

Previous molecular phylogenies of European cyprinids led to some solid facts and some uncertainties. This study is based on a stretch of more than 1 kb in the mitochondrial control region newly sequenced for 35 European cyprinids and on previous cytochrome b and 16S rDNA data. The trees based on the control region are more accurate and robust than those obtained from the two other genes.

Substrate-induced fit of the ATP binding site of cytidine monophosphate kinase from Escherichia coli: time-resolved fluorescence of 3'-anthraniloyl-2'-deoxy-ADP and molecular modeling.

The conformation and dynamics of the ATP binding site of cytidine monophosphate kinase from Escherichia coli (CMPK(coli)), which catalyzes specifically the phosphate exchange between ATP and CMP, was studied using the fluorescence properties of 3'-anthraniloyl-2'-deoxy-ADP, a specific ligand of the enzyme. The spectroscopic properties of the bound fluorescent nucleotide change strongly with respect to those in aqueous solution. These changes (red shift of the absorption and excitation spectra, large increase of the excited state lifetime) are compared to those observed in different solvents.

Performance of 18S rDNA helix E23 for phylogenetic relationships within and between the Rotifera-Acanthocephala clades.

The species diversity of the phylum Rotifera has been largely studied on the basis of morphological characters. However, cladistic relationships within this group are poorly resolved due to extensive homoplasy in morphological traits, substantial phenotypic plasticity and a poor fossil record. We undertook this study to determine if a phylogeny based on partial 18S rDNA, which included the helix E23 of 18S rDNA sequence, was concordant with established taxonomic relationships within the order Ploimida (class: Monogononta).

Identification and characterization of a beta proteasome subunit cluster in the Japanese pufferfish (Fugu rubripes).

The low molecular mass polypeptide (LMP2, LMP7, and MECL-1) genes code for beta-type subunits of the proteasome, a multimeric complex that degrades proteins into peptides as part of the MHC class I-mediated Ag-presenting pathway. These gene products are up-regulated in response to infection by IFN-gamma and replace the corresponding constitutively expressed subunits (X, Y, and Z) during the immune response. In humans, the LMP2 and LMP7 genes both reside within the class II region of the MHC (6p21.

Sonographic detection of intestinal pneumatosis.

Intestinal pneumatosis is an uncommon affection characterized by the presence of gas in the wall of the gastro-intestinal tract. The prognosis of this condition, observed in benign or severe diseases, is based on the outcome of the underlying affection. The diagnosis of pneumatosis intestinalis is unusually made with sonography.

Molecular phylogeny and evolutionary patterns of the european satyrids (Lepidoptera: Satyridae) as revealed by mitochondrial gene sequences.

We examine the phylogenetic relationships of more than 40 species of European satyrids representing six tribes (Coenonymphini, Erebiini, Maniolini, Satyrini, Melanargiini, and Lethini). The analyses are based on comparisons of morphological data and mitochondrial genes encoding the large ribosomal subunit (16S rDNA) and NADH dehydrogenase subunit 1 (ND1). The cladistic reassessment of systematics based on morphological characters differs from the view retained by Miller by a lack in resolution due to the low number of characters used.

Molecular phylogeography of western Mediterranean dusky grouper Epinephelus marginatus.

Intraspecific sequence variation in a portion of the gene coding for cytochrome b in the dusky grouper (Epinephelus marginatus Lowe 1834), an endangered fish species in various regions of the Mediterranean sea, was examined in 29 individuals from the western Mediterranean sea. Sixty-four phylogenetically informative nucleotide positions were present in a 353-base pair cytochrome b sequence, amplified using the polymerase chain reaction. Statistical analysis of the sequence data using a variety of tree-building algorithms separated the taxa into one group of dusky groupers corresponding to some of the Algerian individuals and another regrouped set of fishes originating in France, Tunisia and the remaining Algerian specimens.

Ambulatory blood pressure and neuroendocrine control after diet-assisted gastric restrictive surgery.

Background: Long-term weight control after conventional diet is disappointing but may be improved when diet is assisted by gastric restrictive surgery (GRS).

Objective: To determine the effects of GRS on ambulatory blood pressure (ABP) and neuroendocrine BP control in 28 morbidly obese subjects.

Methods: A BP and heart rate were recorded every 10 min for 25 h before and 4 months after GRS.

Crystallization and preliminary X-ray analysis of the thymidylate kinase from Mycobacterium tuberculosis.

Mycobacterium tuberculosis thymidylate kinase complexed with the substrate deoxythymidine monophosphate was crystallized in the hexagonal space group P6(5)22 or P6(1)22, with unit-cell parameters a = b = 76.62, c = 134.38 A and one single monomer of 23 kDa in the asymmetric unit.

Genetic and biochemical characterization of Salmonella enterica serovar typhi deoxyribokinase.

We identified in the genome of Salmonella enterica serovar Typhi the gene encoding deoxyribokinase, deoK. Two other genes, vicinal to deoK, were determined to encode the putative deoxyribose transporter (deoP) and a repressor protein (deoQ). This locus, located between the uhpA and ilvN genes, is absent in Escherichia coli.

The highly similar TMP kinases of Yersinia pestis and Escherichia coli differ markedly in their AZTMP phosphorylating activity.

Thymidine monophosphate (TMP) kinases are key enzymes in nucleotide synthesis for all living organisms. Although eukaryotic and viral TMP kinases have been studied extensively, little is known about their bacterial counterparts. To characterize the TMP kinase of Yersinia pestis, a chromosomal region encompassing its gene (tmk) was cloned and sequenced; a high degree of conservation with the corresponding region of Escherichia coli was found.

Multinuclear magnetic resonance studies of Escherichia coli adenylate kinase in free and bound forms. Resonance assignment, secondary structure and ligand binding.

The crystal structure of Escherichia coli adenylate kinase (AKe) revealed three main components: a CORE domain, composed of a five-stranded parallel beta-sheet surrounded by alpha-helices, and two peripheral domains involved in covering the ATP in the active site (LID) and binding of the AMP (NMPbind). We initiated a long-term NMR study aiming to characterize the solution structure, binding mechanism and internal dynamics of the various domains. Using single (15N) and double-labeled (13C and 15N) samples and double- and triple-resonance NMR experiments we assigned 97% of the 1H, 13C and 15N backbone resonances, and proton and 13Cbeta resonances for more than 40% of the side chains in the free protein.

Eotaxin expression in Onchocerca volvulus-induced dermatitis after topical application of diethylcarbamazine.

In persons with onchocerciasis, topical application of the anthelminthic diethylcarbamazine (DEC) induces clinical and histologic responses similar to acute papular onchodermatitis, including recruitment of eosinophils to the skin. To determine whether the eosinophil chemokine eotaxin is likely to be associated with eosinophil recruitment in onchodermatitis, DEC was applied to a 5-cm2 area on the skin of infected persons, and biopsies were taken from lesions 24 h later. Histologic analysis showed elevated dermal and epidermal eosinophils compared with tissue from an adjacent (untreated) site.