Novel human prostate cell lines derived from the transition and peripheral zones of the prostate for carcinogenesis studies

Epithelial cell lines were established from the transition and peripheral zones of human prostate by transduction with cdk4 and hTERT. The properties of these lines were investigated using immunocytochemical markers, ability to generate anchorage-independent colonies and by spectral karyotyping (SKY). Cells were exposed to fractionated doses of gamma irradiation to investigate their ability to transform. Cell lines were established from the transition and peripheral zones of human prostate. The expression of CD133, CK5, CK14, CK18, p16, PSCA, p63 and c-myc varied between the lines from the two regions. The line derived from the peripheral zone exhibited properties of a tumour line. A similar pattern was observed in two separate transductions. It was thus unlikely to be an in vitro transformation event, which is very rarely observed with human cells in vitro, and thus more likely to be derived from the immortalisation of a quiescent tumour clone. Fractionated irradiation of the transition zone cell line resulted in forming of transformed colonies. The transformed and tumour line had marked chromosomal rearrangements as demonstrated by SKY analysis. Cell lines have been derived from different zones of human prostate for studies on radiation carcinogenesis. The unirradiated cell line derived from the peripheral zone exhibited chromosomal rearrangements similar to those observed in prostate carcinoma. The cell line derived from the transitional zone exhibited a near diploid karyotype and could be transformed following exposure to fractionated doses of gamma irradiation.     

Serum neutrophil gelatinase-associated lipocalin as a marker of renal function in non-diabetic patients with stage 2-4 chronic kidney disease

The current Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines advocate creatinine-based equations for estimating GFR to identify patients with potential kidney disease and classify them into different stages due to the fact that serum creatinine is very insensitive to changes in the glomerular filtration rate. Very few biomarkers exist for monitoring chronic kidney disease. The aim of the study was to assess whether NGAL could represent a novel, sensitive marker of kidney function in adult patients with CKD. The study was performed on 92 non-diabetic patients with CKD stages 2-4. Serum and urinary NGAL as well as serum cystatin C were measured using commercially available kits. Serum NGAL was related, in univariate analysis, to serum creatinine, urinary NGAL, hemoglobin, hematocrit, leukocyte count, eGFR, and cystatin C. Urinary NGAL correlated with age, hemoglobin, hematocrit, serum creatinine, and eGFR. In multiple regression analysis, predictors of serum NGAL were creatinine (beta value = 0.97, p = 0.005), cystatin C (beta = 0.34, p = 0.01), and eGFR (beta value = 1.77, p = 0.001). In the healthy volunteers, serum NGAL correlated with age, serum creatinine, eGFR, leukocyte count, and cystatin C. Taking into consideration the fact that the recent DOQI (Dialysis Outcomes Quality Initiative) states that individuals with reduced GRF (glomerular filtration rate) are at greater risk for CVD and cardiac deaths, precise evaluation of renal function is important in order to select the appropriate strategy to reduce the cardiovascular risk. NGAL should be investigated as a potential early and sensitive marker of kidney impairment/injury.     

NOGO is increased and binds to BACE1 in sporadic inclusion-body myositis and in AβPP-overexpressing cultured human muscle fibers

Increased amyloid-β precursor protein (AβPP) and amyloid-β (Aβ) accumulation appear to be upstream steps in the pathogenesis of sporadic inclusion-body myositis (s-IBM). BACE1, participating in Aβ production is also increased in s-IBM muscle fibers. Nogo-B and Nogo-A belong to a family of integral membrane reticulons, and Nogo-B binding to BACE1 blocks BACE1 access to AβPP, decreasing Aβ production. We studied Nogo-B and Nogo-A in s-IBM muscle and in our IBM muscle culture models, based on AβPP-overexpression or ER-stress-induction in cultured human muscle fibers (CHMFs). We report that: (1) in biopsied s-IBM fibers, Nogo-B is increased, accumulates in aggregates, is immuno-co-localized with BACE1, and binds to BACE1; Nogo-A is undetectable. (2) In CHMFs, (a) AβPP overexpression increases Nogo-B, Nogo-A, and BACE1, (b) ER stress increases BACE1 but decreases Nogo-B and Nogo-A, (c) Nogo-B and Nogo-A associate with BACE1. Accordingly, two novel mechanisms, AβPP overexpression and ER stress, are involved in Nogo-B and Nogo-A expression in human muscle. We propose that in s-IBM muscle the Nogo-B increase may represent an attempt by muscle fiber to decrease Aβ production. However, the increase of Nogo-B seems insufficient because Aβ continues to accumulate and the disease progresses. We propose that manipulations, which increase Nogo-B in s-IBM muscle might offer a new therapeutic opportunity. Supported by grants (to VA) from the National Institutes of Health (AG 16768 Merit Award), the Muscular Dystrophy Association, and The Myositis Association (to VA), and the Helen Lewis Research Fund.     

Empirical mode decomposition: a novel technique for the study of tremor time series

Tremor is a clinical feature characterized by oscillations of a part of the body. The detection and study of tremor is an important step in investigations seeking to explain underlying control strategies of the central nervous system under natural (or physiological) and pathological conditions. It is well established that tremorous activity is composed of deterministic and stochastic components. For this reason, the use of digital signal processing techniques (DSP) which take into account the nonlinearity and nonstationarity of such signals may bring new information into the signal analysis which is often obscured by traditional linear techniques (e.g. Fourier analysis). In this context, this paper introduces the application of the empirical mode decomposition (EMD) and Hilbert spectrum (HS), which are relatively new DSP techniques for the analysis of nonlinear and nonstationary time-series, for the study of tremor. Our results, obtained from the analysis of experimental signals collected from 31 patients with different neurological conditions, showed that the EMD could automatically decompose acquired signals into basic components, called intrinsic mode functions (IMFs), representing tremorous and voluntary activity. The identification of a physical meaning for IMFs in the context of tremor analysis suggests an alternative and new way of detecting tremorous activity. These results may be relevant for those applications requiring automatic detection of tremor. Furthermore, the energy of IMFs was visualized as a function of time and frequency by means of the HS. This analysis showed that the variation of energy of tremorous and voluntary activity could be distinguished and characterized on the HS. Such results may be relevant for those applications aiming to identify neurological disorders. In general, both the HS and EMD demonstrated to be very useful to perform objective analysis of any kind of tremor and can therefore be potentially used to perform functional assessment.