Portal vein thrombosis and high factor VIII in Turner syndrome

BACKGROUNDS/AIMS: Turner syndrome is not usually associated with thrombotic events. The aim of this study is to report 3 Turner syndrome patients with portal vein thrombosis and, in 2 of them, high factor VIII. These findings are compared to values in Turner syndrome patients without thrombosis and controls. METHODS: In different years, 3 patients with Turner syndrome were initially seen at the Gastroenterology Clinic of Hospital de Clínicas de Porto Alegre, Brazil, for portal vein thrombosis. After the most common causes of portal vein thrombosis and thrombophilias had been excluded, the 2 surviving patients were studied for clotting factors VIII, IX and von Willebrand factor. The same factors were also assessed in 25 Turner syndrome patients without thrombosis and 25 normal girls. RESULTS: One of the patients with portal vein thrombosis died before the study. In the 2 surviving patients, factors VIII and von Willebrand levels were >150 IU/dl, which is considered to be high. In Turner syndrome patients without thrombosis, the mean factor VIII level was 127.2 +/- 41.1 IU/dl and for von Willebrand factor 101.2 +/- 26.9 IU/dl, while in control girls these were 116.0 +/- 27.6 and 94.28 +/- 27.5 IU/dl, respectively. Factor VIII and von Willebrand factor were not different between these 2 groups. When non-O blood group Turner syndrome patients and normal girls were compared, the former had significantly higher levels of factor VIII. CONCLUSIONS: This is the first report on the unusual finding of portal thrombosis in patients with Turner syndrome in whom high levels of factor VIII and von Willebrand factor were found. Factor VIII is higher in the non-O blood group Turner syndrome patients without thrombosis when compared to normal girls.     

Vibrios dominate as culturable nitrogen-fixing bacteria of the Brazilian coral Mussismilia hispida

Taxonomic characterization was performed on the putative N₂-fixing microbiota associated with the coral species Mussismilia hispida, and with its sympatric species Palythoa caribaeorum, P. variabilis, and Zoanthus solanderi, off the coast of São Sebastião (São Paulo State, Brazil). The 95 isolates belonged to the Gammaproteobacteria according to the 16S rDNA gene sequences. In order to identify the isolates unambiguously, pyrH gene sequencing was carried out. The majority of the isolates (n=76) fell within the Vibrio core group, with the highest gene sequence similarity being towards Vibrio harveyi and Vibrio alginolyticus. Nineteen representative isolates belonging to V. harveyi (n=7), V. alginolyticus (n=8), V. campbellii (n=3), and V. parahaemolyticus (n=1) were capable of growing six successive times in nitrogen-free medium and some of them showed strong nitrogenase activity by means of the acetylene reduction assay (ARA). It was concluded that nitrogen fixation is a common phenotypic trait among Vibrio species of the core group. The fact that different Vibrio species can fix N₂ might explain why they are so abundant in the mucus of different coral species.     

A novel supermatrix approach improves resolution of phylogenetic relationships in a comprehensive sample of danthonioid grasses

Phylogeny reconstruction is challenging when branch lengths vary and when different genetic loci show conflicting signals. The number of DNA sequence characters required to obtain robust support for all the nodes in a phylogeny becomes greater with denser taxon sampling. We test the usefulness of an approach mixing densely sampled, variable non-coding sequences (trnL-F; rpl16; atpB-rbcL; ITS) with sparsely sampled, more conservative protein coding and ribosomal sequences (matK; ndhF; rbcL; 26S), for the grass subfamily Danthonioideae. Previous phylogenetic studies of Danthonioideae revealed extensive generic paraphyly, but were often impeded by insufficient character and taxon sampling and apparent inter-gene conflict. Our variably-sampled supermatrix approach allowed us to represent 79% of the species with up to c. 9900 base pairs for taxa representing the major clades. A 'taxon duplication' approach for taxa with conflicting phylogenetic signals allowed us to combine the data whilst representing the differences between chloroplast and nuclear encoded gene trees. This approach efficiently improves resolution and support whilst maximising representation of taxa and their sometimes composite evolutionary histories, resulting in a phylogeny of the Danthonioideae that will be useful both for a wide range of evolutionary studies and to inform forthcoming realignment of generic delimitations in the subfamily.     

Anthropogenic biomes: a key contribution to earth-system science

Human activities now dominate most of the ice-free terrestrial surface. A recent article presents a classification and global map of human-influenced biomes of the world that provides a novel and potentially appropriate framework for projecting changes in earth-system dynamics.     

Mutagenicity and DNA adduct formation of PAH, nitro-PAH, and oxy-PAH fractions of atmospheric particulate matter from São Paulo, Brazil

Urban particulate matter (UPM) contributes to lung cancer incidence. Here, we have studied the mutagenic activity and DNA adduct-forming ability of fractionated UPM extractable organic matter (EOM). UPM was collected with a high-volume sampler in June 2004 at two sites, one at street level adjacent to a roadway and the other inside a park within the urban area of the city of S?o Paulo, Brazil. UPM was extracted using dichloromethane, and the resulting EOM was separated by HPLC to obtain PAH, nitro-PAH, and oxy-PAH fractions which were tested for mutagenicity with the Salmonella strains TA98 and YG1041 with and without S9 metabolic activation. The PAH fraction from both sites showed negligible mutagenic activity in both strains. The highest mutagenic activity was found for the nitro-PAH fraction using YG1041 without metabolic activation; however, results were comparable for both sites. The nitro-PAH and oxy-PAH fractions were incubated with calf thymus DNA under reductive conditions appropriate for the activation of nitro aromatic compounds, then DNA adduct patterns and levels were determined with thin-layer chromatography (TLC) 32P-postlabeling method using two enrichment procedures-nuclease P1 digestion and butanol extraction. Reductively activated fractions from both sites produced diagonal radioactive zones (DRZ) of putative aromatic DNA adducts on thin layer plates with both enrichment procedures. No such DRZ were observed in control experiments using fractions from unexposed filters or from incubations without activating system. Total adduct levels produced by the nitro-PAH fractions were similar for both sites ranging from 30 to 45 adducts per 10(8) normal nucleotides. In contrast, the DNA binding of reductively activated oxy-PAH fractions was three times higher and the adduct pattern consisted of multiple discrete spots along the diagonal line on the thin layer plates. However, DNA adduct levels were not significantly different between the sampling sites. Both samples presented the same levels of mutagenic activity. The response in the Salmonella assay was typical of nitroaromatics. Although, more mutagenic activity was related to the nitro-PAH fraction in the Salmonella assay, the oxy-PAH fractions showed the highest DNA adduct levels. More studies are needed to elucidate the nature of the genotoxicants occurring in S?o Paulo atmospheric samples.     

Description of Culicoides pseudoheliconiae sp.n. from Peruvian Amazon and revalidation of Culicoides contubernalis Ortiz & Leon (Diptera: Ceratopogonidae)

A new species of the Culicoides hylas species group, Culicoides pseudoheliconiae Felippe-Bauer is described and illustrated based on female specimens from Peruvian Amazon, and Culicoides contubernalis Ortiz & Leon from Ecuador is resurrected and redescribed as a valid species. A systematic key, table with numerical characters of females of species of the Culicoides hylas group are given.     

The bisphosphonate zoledronic acid inhibits the growth of HCT-116 colon carcinoma cells and induces tumor cell apoptosis

Besides its preventive action on bone resorption the third generation bisphosphonate zoledronic acid (ZOL) has been shown to display potent inhibitory action on the formation of bone metastases of various human cancers. Recent research also indicates an antitumoral effect on primary tumors and visceral metastases. Here we investigate for the first time the effect of ZOL on the human colon carcinoma cell line HCT-116. ZOL strongly inhibited the proliferation and soft agar colony formation of HCT-116 cells and caused a G1 cell cycle arrest in a population of ZOL treated cells. This cell cycle arrest was accompanied by an induction of apoptosis via a caspase dependent mechanism. Activation of Caspases 3, 7, 8 and 9, cleavage of PARP as well as the release of cytochrome C into the cytosol were detected in HCT-116 cells treated with low micromolar concentrations of ZOL. The induction of the mitochondrial pathway of apoptosis was accompanied by a translocation of Bax into the mitochondria, Bid activation and a decrease of overall Bcl-2 expression. We also detected a cytosolic increase of apoptosis inducing factor (AIF), a trigger of caspase-independent apoptosis. Taken together, our data indicate a potent antitumoral and apoptosis inducing effect of ZOL on HCT-116 colon carcinoma cells. Lilian Sewing and Florian Steinberg contributed equally to this work.