Degree of non-K\"ahlerianity for 6-dimensional nilmanifolds

We use Bott-Chern cohomology to measure the non-K\"ahlerianity of 6-dimensional nilmanifolds endowed with the invariant complex structures in M. Ceballos, A. Otal, L. Ugarte, and R. Villacampa's classification, [Invariant Complex Structures on 6-Nilmanifolds: Classification, Fr\"olicher Spectral Sequence and Special Hermitian Metrics, J. Geom. Anal. (2014)]. We investigate the existence of pluriclosed metric in connection with such a classification

Helicobacter, gamma-glutamyltransferase and cancer: further intriguing connections

Virulence of Helicobacter pylori , H. Suis and other bacteria appears to be partly mediated through a release of gamma-glutamyltransferase (GGT), an enzyme activity capable of promoting biochemical reactions ultimately resulting in damage to gastric epithelium and suppression of immune response. Recently published studies show that secretion of bacterial GGT occurs in the form of exosome-like vescicles. Very similar GGT-rich exosomes have been described to originate from human cancer cells, and the hypothesis is thus forwarded that in the resistant and invasive phenotype of malignant cells such vescicular/exosomal GGT may play roles akin to those described for Helicobacter infection, thus providing a significant contribution to the establishment of cancer metastases

Longitudinal study of the ecap measured in children with cochlear implants

Em crianças usuárias de Implante Coclear (IC), o registro do potencial de ação composto do nervo auditivo evocado eletricamente (ECAP) representa uma maneira de avaliar as modificações nas respostas neurais e entre o feixe de eletrodos e o tecido neural ao longo do tempo. OBJETIVO: Estudar o ECAP em crianças ao longo do primeiro ano de uso do IC. MATERIAL E MÉTODO: As características do ECAP foram analisadas em 13 crianças, implantadas com idades inferiores a três anos de idade. Estudo de série. RESULTADOS: Houve aumento estatisticamente significante na amplitude do pico N1, nos eletrodos basais, entre o segundo e o terceiro retorno. Não foram obtidas diferenças significantes para: a latência do pico N1, o slope, o p-NRT e o período de recuperação entre os retornos. Nos três retornos, a maioria dos sujeitos apresentou tempo de recuperação entre 1000 e 2000µs. CONCLUSÃO: Ao longo do primeiro ano de uso do IC, a estimulação elétrica liberada pelos eletrodos intracocleares não causou alterações significativas às características do ECAP, exceto pelo aumento da amplitude do pico N1.In children with cochlear implant (CI), the recording of the electrically evoked compound action potential (ECAP) of the auditory nerve represents an option to assess changes in auditory nerve responses and the interaction between the electrode bundle and the neural tissue over time. AIM: To study ECAP in children during the first year of CI use. MATERIALS AND METHODS: The ECAP characteristics have been analyzed in 13 children implanted younger than three years of age. Series study. RESULTS: During the first year of CI use there was a significant statistical raise in the N1 peak amplitude, in basal electrodes, between the second and third return visits. There were not any significant differences obtained for N1 peak, latency, slope, p-NRT or recovery time, in the return visits. CONCLUSION: During the first year of CI use, the electrical stimulation provided by the intracochlear electrodes did not cause significant changes to ECAP characteristics, except for an increase in N1 peak amplitude

The potential roles of gamma-glutamyltransferase activity in the progression of atherosclerosis and cardiovascular diseases.

The oxidation of low density lipoproteins (LDL) is regarded as a critical factor in the pathogenesis of atherosclerosis, especially the initial steps of the disease. In addition, other oxidative events have been shown to participate in the progression of atherosclerosis and precipitation of cardiovascular events, through modulation of important components of lesions of the vessel wall (smooth muscle cell proliferation, protease/antiprotease balance, endothelial functions). Our recent studies have provided evidence that the enzyme gamma-glutamyltransferase (GGT), normally found in serum, is often accumulated within the plaque environment in substantial amounts, and that this activity is a potential source of a variety of prooxidant species. Concurrently, epidemiological research has conclusively documented that the serum levels of GGT are an independent factor in prognosis of myocardial infarction and stroke in atherosclerotic patients. Several signs suggest that the GGT appearing in plaque tissue may originate from the serum enzyme, which in facts associates with the circulating lipoprotein fractions. Thus, data seem to point out that pathogenesis of atherosclerosis – and in particular of the events leading to progression of the disease and acute cardiovascular events – might include an as yet unexplored pathway, based on the prooxidant effects of gamma-glutamyltransferase accumulating as a result of LDL entry in the vessel wall

Open Philology at the University of Leipzig

The Open Philology Project at the University of Leipzig aspires to re-assert the value of philology in its broadest sense. Philology signifies the widest possible use of the linguistic record to enable a deep understanding of the complete lived experience of humanity. Pragmatically, we focus on Greek and Latin because (1) substantial collections and services are already available within these languages, (2) substantial user communities exist (c. 35,000 unique users a month at the Perseus Digital Library), and (3) a European-based project is better positioned to process extensive cultural heritage materials in these languages rather than in Chinese or Sanskrit. The Open Philology Project has been designed with the hope that it can contribute to any historical language that survives within the human record. It includes three tasks: (1) the creation of an open, extensible, repurposable collection of machine-readable linguistic sources; (2) the development of dynamic textbooks that use annotated corpora to customize the vocabulary and grammar of texts that learners want to read, and at the same time engage students in collaboratively producing new annotated data; (3) the establishment of new workflows for, and forms of, publication, from individual annotations with argumentation to traditional publications with integrated machine-actionable data

Plasma membrane gamma-glutamyltransferase activity facilitates the uptake of vitamin C in melanoma cells.

Adequate cellular transport of ascorbic acid (AA) and its oxidation product dehydroascorbate (DHA) is assured through specific carriers. It was shown that vitamin C is taken up as DHA by most cell types, including cancer cells, via the facilitative GLUT transporters. Thus, AA oxidation to DHA can be considered a mechanism favoring vitamin C uptake and intracellular accumulation. We have investigated whether such an AA-oxidizing action might be provided by plasma membrane g-glutamyltransferase (GGT), previously shown to function as an autocrine source of prooxidants. The process was studied using two distinct human metastatic melanoma clones. It was observed that the Me665/2/60 clone, expressing high levels of membrane GGT activity, was capable of effecting the oxidation of extracellular AA, accompanied by a marked increase of intracellular AA levels. The phenomenon was not observed with Me665/2/21 cells, possessing only traces of membrane GGT. On the other hand, AA oxidation and stimulation of cellular uptake were indeed observed after transfection of 2/21 cells with cDNA coding for GGT. The mechanism of GGTmediated AA oxidation was investigated in acellular systems, including GGT and its substrate glutathione. The process was observed in the presence of redox-active chelated iron(II) and of transferrin or ferritin, i.e., two physiological iron sources. Thus, membrane GGT activity—often expressed at high levels in human malignancies—can oxidize extracellular AA and promote its uptake efficiently

Discrepancy between FLC assays: Only a problem of quantification?

Immunoglobulin light chains not associated with heavy chains (free light chains, FLC) are found in serum. A growing clinical importance has been assigned to the quantification of the kappa and lambda FLC in serum in the management of plasma cell dyscrasias. At present, automated immunoassays are the only available techniques allowing quantitative determination of serum FLC. Unfortunately, the two reagents available for FLC assay, provide sometimes divergent results. It has been proposed that the different results, unpredictably affecting individual serum samples, are due the different reactivity of reagents against FLC oligomers that are known to be present to a variable extent in serum, especially when lambda FLC are involved. We report a case where we demonstrated that the two reagents recognized differently FLC monomer and dimers

Evaluation of analytical performance of a novel immunoenzymometric assay for cTnI

Letter to the Editor. We evaluated the analytical performance of the immunoenzymometric assay for the cTnI, named ST AIA-PACK cTnI 3rd-Gen, using the automated AIA-2000 platform (Tosoh Corporation, Tokyo, Japan). This method is a two-site immunoenzymometric assay, which uses a combination of two monoclonal antibodies, respectively directed to 41–49 and 87–91 amino acids of the cTnI peptide chain, and the ternary troponin ITC complex as a calibration antigen [1]