TMEFF2 Is a PDGF-AA Binding Protein with Methylation-Associated Gene Silencing in Multiple Cancer Types Including Glioma

BACKGROUND: TMEFF2 is a protein containing a single EGF-like domain and two follistatin-like modules. The biological function of TMEFF2 remains unclear with conflicting reports suggesting both a positive and a negative association between TMEFF2 expression and human cancers. METHODOLOGY/PRINCIPAL FINDINGS: Here we report that the extracellular domain of TMEFF2 interacts with PDGF-AA. This interaction requires the amino terminal region of the extracellular domain containing the follistatin modules and cannot be mediated by the EGF-like domain alone. Furthermore, the extracellular domain of TMEFF2 interferes with PDGF-AA-stimulated fibroblast proliferation in a dose-dependent manner. TMEFF2 expression is downregulated in human brain cancers and is negatively correlated with PDGF-AA expression. Suppressed expression of TMEFF2 is associated with its hypermethylation in several human tumor types, including glioblastoma and cancers of ovarian, rectal, colon and lung origins. Analysis of glioma subtypes indicates that TMEFF2 hypermethylation and decreased expression are associated with a subset of non-Proneural gliomas that do not display CpG island methylator phentoype. CONCLUSIONS/SIGNIFICANCE: These data provide the first evidence that TMEFF2 can function to regulate PDGF signaling and that it is hypermethylated and downregulated in glioma and several other cancers, thereby suggesting an important role for this protein in the etiology of human cancers

Pacientes assintomáticos apresentam infecção relacionada ao cateter venoso utilizado para terapia nutricional parenteral Asymptomatic patients present infection related to the central venous catheter used for total parenteral nutrition

OBJETIVO: Avaliar a freqüência de infecção relacionada ao cateter venoso central em pacientes submetidos a terapia nutricional parenteral. MÉTODOS: Foram analisados os cateteres venosos centrais de pacientes em terapia nutricional parenteral que tiveram a indicação de retirada do cateter venoso central por infecção, alta hospitalar, ou trombose. Os pacientes com infecção foram denominados de Grupo 1 e os demais de Grupo 2. RESULTADOS: Não houve diferença estatisticamente significante quanto ao estado nutricional dos 18 pacientes analisados. Foram analisados 28 cateteres e destes 68% estavam infectados, sendo 72% do Grupo 1 e 28% do Grupo 2 (assintomáticos). No Grupo 1, houve infecção sistêmica em 70% dos casos, já no Grupo 2 a hemocultura foi positiva em 17% dos casos. A colonização por Staphylococcus sp. ocorreu em 48% dos casos, seguida de Candida sp. (21%), Enterococcus faecalis (16%), Pseudomonas aerurginosa (10%) e Proteus sp.(5%). CONCLUSÃO: A contaminação de cateter venoso central utilizado para terapia nutricional parenteral é freqüente. Mesmo pacientes assintomáticos recebendo nutrição parenteral têm uma incidência maior de infecção por Candida sp. Portanto é necessária a criação de barreiras que impeçam a colonização destes cateteres venosos centrais, a fim de diminuir a morbimortalidade de pacientes dependentes deste tipo de terapia.<br>OBJECTIVE: The aim of this study was to evaluate the frequency of central venous catheter-related infections in hospitalized patients receiving total parenteral nutrition. METHODS: Central venous catheters were analyzed immediately after removal due to infection, hospital discharge or thrombosis. The patients with catheter-related infection were named Group 1 and the other patients were named Group 2. RESULTS: Eighteen patients were studied. There was no statistically significant difference in nutritional status between the two groups. A total of 28 catheters were analyzed. Sixty-eight percent of the catheters were infected: 72% of them were from Group 1 and 28% from Group 2 (asymptomatic patients). Systemic infection was diagnosed in 70% of the patients from Group 1. Positive blood culture was found in 17% of the patients from Group 2. The microorganisms found were: Staphylococcus sp. (48%), Candida sp. (21%), Enterococcus faecalis (16%), Pseudomonas aerurginosa (10%) and Proteus sp. (5%). CONCLUSION: Central venous catheter infection is common in hospitalized asymptomatic patients. Patients receiving total parenteral nutrition are most frequently infected with Candida sp. Therefore, the creation of barriers that block colonization in the central venous catheter is essential to decrease the morbidity and mortality among patients that depend on total parenteral nutrition

From Chemical Gardens to Chemobrionics

Chemical gardens in laboratory chemistries ranging from silicates to polyoxometalates, in applications ranging from corrosion products to the hydration of Portland cement, and in natural settings ranging from hydrothermal vents in the ocean depths to brinicles beneath sea ice. In many chemical-garden experiments, the structure forms as a solid seed of a soluble ionic compound dissolves in a solution containing another reactive ion. In general any alkali silicate solution can be used due to their high solubility at high pH. The cation should not precipitate with the counterion of the metal salt used as seed. A main property of seed chemical-garden experiments is that initially, when the fluid is not moving under buoyancy or osmosis, the delivery of the inner reactant is diffusion controlled. Another experimental technique that isolates one aspect of chemical-garden formation is to produce precipitation membranes between different aqueous solutions by introducing the two solutions on either side of an inert carrier matrix. Chemical gardens may be grown upon injection of solutions into a so-called Hele-Shaw cell, a quasi-two-dimensional reactor consisting in two parallel plates separated by a small gap