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Fragmented DNA (fragmented + dna)
Selected AbstractsIn vivo analysis reveals different apoptotic pathways in pre- and postmigratory cerebellar granule cells of rabbitDEVELOPMENTAL NEUROBIOLOGY, Issue 4 2004Laura Lossi Abstract Naturally occurring neuronal death (NOND) has been described in the postnatal cerebellum of several species, mainly affecting the cerebellar granule cells (CGCs) by an apoptotic mechanism. However, little is known about the cellular pathway(s) of CGC apoptosis in vivo. By immunocytochemistry, in situ detection of fragmented DNA, electron microscopy, and Western blotting, we demonstrate here the existence of two different molecular mechanisms of apoptosis in the rabbit postnatal cerebellum. These two mechanisms affect CGCs at different stages of their maturation and migration. In the external granular layer, premigratory CGCs undergo apoptosis upon phosphorylation of checkpoint kinase 1 (Chk1), and hyperphosphorylation of retinoblastoma protein. In postmigratory CGCs within the internal granular layer, caspase 3 and to a lesser extent 7 and 9 are activated, eventually leading to poly-ADP-ribose polymerase-1 (PARP-1) cleavage and programmed cell death. We conclude that NOND of premigratory CGCs is linked to activation of DNA checkpoint and alteration of normal cell cycle, whereas in postmigratory CGCs apoptosis is, more classically, dependent upon caspase 3 activation. © 2004 Wiley Periodicals, Inc. J Neurobiol 60: 437,452, 2004 [source] Optimization of DNA Extraction from Low-Yield and Degraded Samples Using the BioRobot® EZ1 and BioRobot® M48JOURNAL OF FORENSIC SCIENCES, Issue 5 2006Ram Kishore Ph.D. ABSTRACT: Robotic extraction of DNA from dilutions of blood and semen using either the BioRobots® EZ1 or BioRobots® M48 consistently produced lower recoveries than standard organic extractions of the same samples. In an effort to increase the efficiency of robotically extracted DNA, glycogen and carrier RNA were added following cell lysis. The addition of glycogen, postlysis, resulted in no improvement in DNA recovery with the BioRobot® EZ1. However, when carrier RNA was added to the cell lysate of limited and degraded samples extracted on the EZ1 or the M48, DNA recoveries dramatically increased four- to 20-fold. DNA yields obtained by robotic extraction in the presence of carrier RNA were as high, or higher, as those obtained by organic extraction lacking carrier RNA, while experiments that utilized carrier RNA in both types of extractions showed increased sensitivity for both methods. Furthermore, carrier RNA substantially increased the recovery of fragmented DNA with the EZ1. [source] Differential kinetic features by tumour topography in cutaneous small-cell neuroendocrine (Merkel cell) carcinomasJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 9 2007L Pozo Abstract Background/Objectives Merkel cell carcinomas (MCC) reveal epithelial and neuroendocrine differentiation, but its topographic cell kinetics remains unknown. This study analyses proliferation, apoptosis, and DNA ploidy by topography, features that can help planning therapeutic protocols. This study topographically analyses proliferation, apoptosis, and DNA ploidy. Methods We selected 27 small-cell MCCs (expressing one epithelial and two neural markers, with consistent ultrastructural findings) to evaluate mitotic figure counting, Ki-67 index, apoptosis index based on the in situ end labelling of fragmented DNA (using Escherichia coli DNA polymerase I, Klenow fragment), DNA ploidy, and BCL2 and TP53 immuno-expression. At least 50 high-power fields were screened per topographic compartment (superficial or papillary dermis, and deep or reticular dermis), recording average and standard deviation for each variable. Variables were statistically compared in each tumour compartment using analysis of variance and Student's t -test (significant if P < 0.05). Results MCCs revealed superficial aneuploid DNA content, and no topographic differences for proliferation markers. Apoptosis showed significantly lower values in the deep compartment (average, P = 0.0050, and standard deviation, P = 0.0074), correlating with increased BCL2 and TP53 immuno-expressions. Conclusions High homogeneously distributed proliferation and superficial aneuploid DNA content defines MCCs. Apoptosis follows proliferation in superficial compartments, being less variable and proliferation independent in deep compartments, where it is inversely correlated with BCL2/TP53 expression. [source] Induction of apoptosis in the LNCaP human prostate carcinoma cell line and prostate adenocarcinomas of SV40T antigen transgenic rats by the Bowman,Birk inhibitorPATHOLOGY INTERNATIONAL, Issue 11 2009MingXi Tang The soybean-derived serine protease inhibitor, Bowman,Birk inhibitor (BBI), has been reported as a potent chemoprevention agent against several types of tumors. The present study was undertaken to evaluate the effects of BBI on androgen-sensitive/dependent prostate cancers using a human prostate cancer cell (LNCaP) and the transgenic rats developing adenocarcinoma of the prostate (TRAP) model. Treatment of LNCaP prostate cancer cells with 500 µg/mL BBI resulted in inhibition of viability measured on WST-1 assays, with induction of connexin 43 (C×43) and cleaved caspase-3 protein expression. Feeding of 3% roughly prepared BBI (BBIC) to TRAP from the age 3 weeks to 13 weeks resulted in significant reduction of the relative epithelial areas within the acinus and multiplicity of the adenocarcinomas in the lateral prostate lobes. C×43- and terminal deoxynucleotidyl transferase mediated dUTP-biotin end labeling of fragmented DNA (TUNEL)-positive apoptotic cancer cells were more frequently observed in the lateral prostates treated with BBIC than in the controls. These in vivo and in vitro results suggest that BBI possesses chemopreventive activity associated with induction of C×43 expression and apoptosis. [source] Correlation between neutral alpha-glucosidase activity and sperm DNA fragmentationANDROLOGIA, Issue 5 2009M. Watanabe Summary To evaluate the association between neutral ,-glucosidase (NAG) activity and sperm DNA fragmentation (DFI), ejaculates from 24 men undergoing evaluation for sperm DNA damage as a part of infertility assessment were analysed. The mean ± SD and range for the semen quality of the 24 ejaculates are as follows: volume (3.1 ± 1.3, 1.8,6.0 ml); sperm concentration (45.6 ± 41.1, 1.3,151.2 × 106 ml,1); sperm motility (52.8 ± 28.8, 1,95%); sperm with fragmented DNA (17.6 ± 15.4, 1.7,56.0%); sperm with immature chromatin (9.6 ± 3.8, 2.5,19.1%); NAG activity (37.9 ± 18.3, 4.4,75.3 mU ml,1). The only sperm parameter significantly correlated with neutral ,-glucosidase is the percentage of sperm DFI [correlation coefficient (r) = 0.4376, P = 0.03]. [source] | ||||||||||