Brachyury oncogene is a prognostic factor in high-risk testicular germ cell tumors.

The T-box transcription factor Brachyury has been considered a cancer-specific marker and a novel oncotarget in solid tumors. Brachyury overexpression has been described in various cancers, being associated with epithelial-mesenchymal transition, metastasis, and poor prognosis. However, its clinical association with testicular germ cell tumor is unknown. We analyzed the expression of Brachyury by immunohistochemistry in a series of well-characterized testicular germ cell tumor samples and at transcript level by in silico analysis. Additionally, we aimed to investigate the clinical significance of Brachyury in testicular germ cell tumor. Brachyury cytoplasm immunostaining was present in 89.6% (86/96) of cases with nuclear staining observed in 24% (23/96) of testicular germ cell tumor. Bioinformatics microarray expression analysis of two independent cohorts of testicular germ cell tumors showed similar results with increased levels of Brachyury in testicular germ cell tumors and metastasis compared with normal testis. Clinically, Brachyury nuclear staining was statistically associated with lower event-free survival (p = 0.04) and overall survival (p = 0.01) in intermediate/high-risk testicular germ cell tumors. Univariate analysis showed that Brachyury nuclear subcellular localization was a predictor of poor prognosis (p = 0.02), while a tendency was observed by multivariate analysis (HR: 3.56, p = 0.06). In conclusion, these results indicate that Brachyury plays an oncogenic role in testicular germ cell tumors and its subcellular localization in the nucleus may constitute a novel biomarker of poor prognosis and a putative oncotarget for intermediate/high-risk testicular germ cell tumor patients.

Absence of microsatellite instability and BRAF (V600E) mutation in testicular germ cell tumors.

Testicular germ cell tumors (TGCT) are the most common malignant neoplasm in young men. DNA mismatch repair deficiency can lead to microsatellite instability (MSI), an important mechanism of genetic instability. A mutation of the BRAF gene has been implicated in the pathogenesis of several solid tumors and has recently become an important therapeutic target. The role of MSI and BRAF gene mutation in TGCT, particularly in refractory disease, is poorly understood and reported findings are controversial. In this study, we aimed to determine the frequency and clinical impact of MSI status and BRAF mutations in TGCT. DNA was isolated from formalin-fixed paraffin embedded (FFPE) tissue from 150 TGCT cases. The MSI phenotype was evaluated using multiplex PCR for five quasimonomorphic mononucleotide repeat markers. Exon 15 of the BRAF oncogene (V600E) was analyzed by PCR, followed by direct sequencing. Sixteen percent of cases were considered to have refractory disease. In a small subset of cases (17 for MSI and 18 for BRAF), the quantity and quality of DNA recovery were poor and therefore, were unable to be analyzed. The remaining 133 TGCT cases showed a complete absence of MSI. Of the 132 cases successfully evaluated for BRAF mutations, all were V600E wild-type. In conclusion, despite a distinct response of testicular germ cell tumors to therapy, microsatellite instability, and the BRAF V600E mutation were absent in all testicular germ cell tumors tested in this study.

Fractal structures in nonlinear plasma physics.

Fractal structures appear in many situations related to the dynamics of conservative as well as dissipative dynamical systems, being a manifestation of chaotic behaviour. In open area-preserving discrete dynamical systems we can find fractal structures in the form of fractal boundaries, associated to escape basins, and even possessing the more general property of Wada. Such systems appear in certain applications in plasma physics, like the magnetic field line behaviour in tokamaks with ergodic limiters. The main purpose of this paper is to show how such fractal structures have observable consequences in terms of the transport properties in the plasma edge of tokamaks, some of which have been experimentally verified. We emphasize the role of the fractal structures in the understanding of mesoscale phenomena in plasmas, such as electromagnetic turbulence.

Effects of confinement on the electron-phonon interaction in Al(0.18)Ga(0.82)As/GaAs quantum wells.

Photoluminescence measurements at different temperatures have been performed to investigate the effects of confinement on the electron-phonon interaction in GaAs/AlGaAs quantum wells (QWs). A series of samples with different well widths in the range from 150 up to 750 Å was analyzed. Using a fitting procedure based on the Pässler-p model to describe the temperature dependence of the exciton recombination energy, we determined a fit parameter which is related to the strength of the electron-phonon interaction. On the basis of the behavior of this fit parameter as a function of the well width thickness of the samples investigated, we verified that effects of confinement on the exciton recombination energy are still present in QWs with well widths as large as 450 Å. Our findings also show that the electron-phonon interaction is three times stronger in GaAs bulk material than in Al(0.18)Ga(0.82)As/GaAs QWs.

Microencapsulation of antibiotic rifampicin in poly(3-hydroxybutyrate-co-3-hydroxyvalerate).

The aim of this study was the preparation of microparticles containing rifampicin using a biodegradable polymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) for oral administration produced by a bacteria. The poly(3-hydroxybutyrate-co-3-hydroxyvalerate) microparticles with and without rifampicin were prepared by the emulsification and solvent evaporation method, in which chloroform and polyvinyl alcohol are used as the solvent and emulsifier, respectively. Microparticles were obtained within a size range of 20-60 microm by changing the initial poly(3-hydroxybutyrate-co-3-hydroxyvalerate), polyvinyl alcohol and rifampicin concentrations. An encapsulation efficiency value of 14% was obtained. The optimized total yield of 60% of the poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/ rifampicin was obtained. A load of 0.035 mg/1 mg of PHBV was reached. Almost 90% of the drug loaded in the microparticles was released after 24 h. The size, encapsulation efficiency and ribampicin release of the microparticles varied as a function of the initial poly(3-hydroxybutyrate-co-3-hydroxyvalerate), polyvinyl alcohol and rifampicin concentrations. It was demonstrated that the microencapsulated rifampicin, although was not totally available in the medium, exhibited a similar inhibition value as free rifampicin at 24 h of incubation with S. aureus. Cytotoxicity assays demonstrated a reduction of the toxicity when rifampicin was microencapsulated in poly(3-hydroxybutyrate-co-3-hydroxyvalerate) while maintaining its antibacterial activity.

Inversion in the change of the refractive index and memory effect near the nematic-isotropic phase transition in a lyotropic liquid crystal.

This work demonstrates the occurrence of dn/dT inversion from negative to positive near the nematic-isotropic phase transition in a lyotropic liquid crystal. It is suggested that this effect can be attributed to a sudden increase of the electronic polarizability due to a change in the micelle shape near this phase transition. Formation of a long lasting lenslike element within the sample when it is irradiated at moderately high laser powers is also reported. This permanent lens is erasable by increasing the temperature above the nematic-isotropic transition temperature.

Nodular diabetic glomerulosclerosis without diabetes mellitus.

A 66-year-old white man presented with severe chronic renal failure. He had no past or present symptomatic glucose intolerance nor a family history of diabetes mellitus. Several fasting plasma glucose determinations, hemoglobin Alc and an oral glucose tolerance test were normal. Funduscopic ophthalmoscopy and retinal fluorescein angiography did not demonstrate diabetic retinopathy. The kidney biopsy showed nodular diabetic nephropathy, with increased mesangial matrix, thickened glomerular basement membrane, and afferent and efferent glomerular arteriolar hyalinization. The diagnosis of nodular diabetic nephropathy was made in this patient in the absence of past or present or familial evidence of diabetes mellitus.

[Expansive mass of the posterior region of the 3d ventricle (tumors of the pineal region)]. / Massa espansiva da região posterior do terceiro ventrículo (tumores da região da pineal).

Tumours of the pineal region are rare. Clinical and CT aspects, and results of the treatment of 12 cases observed in a 5 years period (1979-1984) are described. The authors consider the supracerebellar infratentorial approach, formerly described by Krause in 1926 and reintroduced by Stein in 1971, the best for the surgical management of these tumours.

[Hepatitis B antigens systems in schistosomiasis mansoni]. / Sistemas antigênicos da hepatite B na esquistossomose mansôncia.

The authors have studied the antigenic systems HBs and HBe and B virus hepatitis in 155 patients with mansonic schistosomiasis and have found: a) 22,5% HBsAg positivity in patients with the hepatosplenic form of the disease which was associated with histologic liver alterations and 8,7% anti-HBs positivity in patients with the hepatointestinal form of the disease which was associated with a preserved liver histology; in controls they have found 1% positivity for HBsAg. b) HBeAg and anti-HBe were of good prognostic value.

[O and C prenylated chalcones with antineoplastic and antibiotic activities isolated from Lonchocarpus neuroscapha Benth]. / Chalconas o- ec-preniladas com atividades antibiótica e antineoplásica, isoladas de Lonchocarpus neuroscapha Benth

In the course of our program on the antimicrobial and antineoplastic substances from higher plants we have studied many flavonoid compounds isolated from root back of Lonchocarpus neuroscapha Benth. In the present paper a slight effect on sarcoma 180 and Ehrlich carcinoma of cordoin, 4-hydroxy-cordoin and 4-hydroxy-derricin, as well as the only observed effect of derricin on sarcoma 180 were observed. The antimicrobial action of four prenylated chalcones, i.e. 4-hydroxy-derricin, 4-hydroxy-lonchocarpin, 4-hydroxy-cordoin and 4-hydroxy-isocordoin is reported.