Downregulation of intracellular nm23-H1 prevents cisplatin-induced DNA damage in oesophageal cancer cells: possible association with Na+, K+-ATPase

Previously, we showed that expression of nm23-H1 is associated inversely with sensitivity to cisplatin in human oesophageal squamous cell carcinoma (OSCC). The present study was undertaken to investigate the association of nm23-H1 expression with cisplatin-induced DNA damage in OSCC using antisense nm23-H1 transfectants. YES-2/AS-12, an antisense nm23-H1-transfected OSCC cell line, showed significantly reduced expression of intracellular nm23-H1 protein compared with that in parental YES-2 cells and YES-2/Neo transfectants. Surface expression of nm23-H1 protein was not observed in any of the three cell lines. PCR analysis for DNA damage demonstrated that YES-2/AS-12 cells were more resistant to nuclear and mitochondrial DNA damage by cisplatin than were YES-2/Neo cells. In addition, mitochondrial membrane potentials and DNA fragmentation assays confirmed that YES-2/AS-12 was more resistant than YES-2/Neo to apoptosis induced by cisplatin. In contrast, YES-2/AS-12 was more sensitive to ouabain, a selective inhibitor of Na+, K+-ATPase, than YES-2 and YES-2/Neo. Pre-treatment with ouabain resulted in no differences in cisplatin sensitivity between the three cell lines examined. Intracellular platinum level in YES-2/AS-12 was significantly lower than that in YES-2 and YES-2/Neo following incubation with cisplatin, whereas ouabain pre-treatment resulted in no differences in intracellular platinum accumulations between the three cell lines. Our data support the conclusion that reduced expression of intracellular nm23-H1 in OSCC cells is associated with cisplatin resistance via the prevention of both nuclear and mitochondrial DNA damage and suggest that it may be related to Na+, K+-ATPase activity, which is responsible for intracellular cisplatin accumulation. © 2000 Cancer Research Campaig

Peanut Chlorotic Streak Virus, a New Caulimovirus Infecting Peanuts (Arachis hypogaea) in India

Peanut (Arachis hypogaea [groundnut]) plants with reduced leaflets, chlorotic streaks, and stunting were observed during surveys for diseases caused by peanut viruses in India. These peanut plants were infected with a new caulimovirus designated peanut chlorotic streak virus (PClSV). PClSV was mechanically transmissible to several plants in Leguminosae and Solanaceae but was not transmitted by Aphis craccivora or Myzus persicae. Purified from Nicotiana clevelandii leaves, PClSV contained isometric particles 52 ± 3 nm in diameter. The virus was not related to cauliflower mosaic, figwort mosaic, or soybean chlorotic mottle viruses. Inclusion bodies similar to those produced by caulimoviruses were observed in the cytoplasm of infected Nicotiana rustica and A. hypogaea leaves. Purified PClSV contained two polypeptides with relative molecular masses of 58 and 51 kDa. The size of double-stranded DNA was estimated as approximately 8.1 kbp, which contained two single-stranded discontinuities. The physical map of the PClSV genome was distinctly different from those of other caulimoviruses

Serum soluble-Fas is a predictor of red blood cell transfusion in critically ill patients

OBJECTIVE: To investigate the relation between the need for red blood cell transfusion and serum levels of soluble-Fas, erythropoietin and inflammatory cytokines in critically ill patients with and without acute kidney injury. METHODS: We studied critically ill patients with acute kidney injury (n=30) and without acute kidney injury (n=13), end-stage renal disease patients on hemodialysis (n=25) and healthy subjects (n=21). Serum levels of soluble-Fas, erythropoietin, interleukin 6, interleukin 10, iron status, hemoglobin and hematocrit concentration were analyzed in all groups. The association between these variables in critically ill patients was investigated. RESULTS: Critically ill patients (acute kidney injury and non-acute kidney injury patients) had higher serum levels of erythropoietin than the other groups. Hemoglobin concentration was lower in the acute kidney injury patients than in other groups. Serum soluble-Fas levels were higher in acute kidney injury and end-stage renal disease patients. Critically ill patients requiring red blood cell transfusions had higher serum levels of soluble-Fas (5,906±2,047 and 1,920±1,060; p<0.001), interleukin 6 (518±537 and 255+502; p=0.02) and interleukin 10 (35.8±30.7 and 18.5±10.9; p=0.02), better iron status and higher mortality rates in the first 28 days in intensive care unit. Serum soluble-Fas levels were independently associated with the number of red blood cell units transfused (p=0.02). Serum soluble-Fas behaved as an independent predictor of the need for red blood cell transfusion in critically ill patients (p=0.01). CONCLUSIONS: Serum soluble-Fas level is an independent predictor of the need for red blood cell transfusion in critically ill patients with or without acute kidney injury. Further studies are warranted to reconfirm this finding.OBJETIVO: Investigar a relação entre a transfusão de hemácias e os níveis séricos de Fas solúvel, eritropoietina e citocinas inflamatórias em pacientes gravemente enfermos, com e sem insuficiência renal aguda. MÉTODOS: Os seguintes grupos foram estudados: pacientes gravemente enfermos com insuficiência renal aguda (n=30) e sem insuficiência renal aguda (n=13), pacientes portadores de doença renal crônica terminal em hemodiálise (n=25) e indivíduos saudáveis (n=21). Os níveis séricos de Fas solúvel, eritropoietina, interleucina 6, interleucina 10 e ferro, além da concentração de hemoglobina e de hematócrito, foram analisados em todos os grupos. A associação entre tais variáveis foram estudadas nos pacientes gravemente enfermos. RESULTADOS: Os níveis séricos de eritropoietina mostraram-se mais elevados nos pacientes gravemente enfermos do que nos dos demais grupos. Concentrações mais baixas de hemoglobina foram documentadas nos pacientes com insuficiência renal aguda em relação aos demais. Níveis séricos mais elevados de Fas solúvel foram observados nos pacientes com insuficiência renal aguda e doença renal crônica terminal. Pacientes gravemente enfermos transfundidos apresentaram níveis séricos mais elevados de Fas solúvel (5.906±2.047 e 1.920±1.060; p<0,001), interleucina 6 (518±537 e 255±502; p=0,02), interleucina 10 (35,8±30,7 e 18,5±10,9; p=0,02) e ferro, além de maior mortalidade em 28 dias. Os níveis séricos de Fas solúvel mostraram-se independentemente associados ao número de transfusões (p=0,02). O nível sérico de Fas solúvel foi um preditor independente da necessidade de transfusão de hemácias em pacientes gravemente enfermos (p=0,01). CONCLUSÃO: O nível sérico de Fas solúvel é um preditor independente da necessidade de transfusão de hemácias em pacientes gravemente enfermos, com ou sem insuficiência renal aguda. Mais estudos clínicos e laboratoriais são necessários para confirmar tal resultado.Universidade Federal de São Paulo (UNIFESP)Hospital Israelita Albert EinsteinUNIFESPSciEL

Gene and pathway identification with Lp penalized Bayesian logistic regression

<p>Abstract</p> <p>Background</p> <p>Identifying genes and pathways associated with diseases such as cancer has been a subject of considerable research in recent years in the area of bioinformatics and computational biology. It has been demonstrated that the magnitude of differential expression does not necessarily indicate biological significance. Even a very small change in the expression of particular gene may have dramatic physiological consequences if the protein encoded by this gene plays a catalytic role in a specific cell function. Moreover, highly correlated genes may function together on the same pathway biologically. Finally, in sparse logistic regression with <it>L</it>_{<it>p </it>}(<it>p </it>< 1) penalty, the degree of the sparsity obtained is determined by the value of the regularization parameter. Usually this parameter must be carefully tuned through cross-validation, which is time consuming.</p> <p>Results</p> <p>In this paper, we proposed a simple Bayesian approach to integrate the regularization parameter out analytically using a new prior. Therefore, there is no longer a need for parameter selection, as it is eliminated entirely from the model. The proposed algorithm (BLpLog) is typically two or three orders of magnitude faster than the original algorithm and free from bias in performance estimation. We also define a novel similarity measure and develop an integrated algorithm to hunt the regulatory genes with low expression changes but having high correlation with the selected genes. Pathways of those correlated genes were identified with DAVID <url>http://david.abcc.ncifcrf.gov/</url>.</p> <p>Conclusion</p> <p>Experimental results with gene expression data demonstrate that the proposed methods can be utilized to identify important genes and pathways that are related to cancer and build a parsimonious model for future patient predictions.</p

Expedition 382 Preliminary Report: Iceberg Alley and Subantarctic Ice and Ocean Dynamics

This is the final version. Available from International Ocean Discovery Program via the DOI in this record. International Ocean Discovery Program (IODP) Expedition 382, Iceberg Alley and Subantarctic Ice and Ocean Dynamics, investigated the long-term climate history of Antarctica, seeking to understand how polar ice sheets responded to changes in insolation and atmospheric CO2 in the past and how ice sheet evolution influenced global sea level and vice versa. Five sites (U1534–U1538) were drilled east of the Drake Passage: two sites at 53.2°S at the northern edge of the Scotia Sea and three sites at 57.4°–59.4°S in the southern Scotia Sea. We recovered continuously deposited late Neogene sediment to reconstruct the past history and variability in Antarctic Ice Sheet (AIS) mass loss and associated changes in oceanic and atmospheric circulation. The sites from the southern Scotia Sea (Sites U1536–U1538) will be used to study the Neogene flux of icebergs through “Iceberg Alley,” the main pathway along which icebergs calved from the mar- gin of the AIS travel as they move equatorward into the warmer wa- ters of the Antarctic Circumpolar Current (ACC). In particular, sediments from this area will allow us to assess the magnitude of iceberg flux during key times of AIS evolution, including the following: • The middle Miocene glacial intensification of the East Antarctic Ice Sheet, • The mid-Pliocene warm period, • The late Pliocene glacial expansion of the West Antarctic Ice Sheet, • The mid-Pleistocene transition (MPT), and • The “warm interglacials” and glacial terminations of the last 800 ky. We will use the geochemical provenance of iceberg-rafted detritus and other glacially eroded material to determine regional sources of AIS mass loss. We will also address interhemispheric phasing of ice sheet growth and decay, study the distribution and history of land-based versus marine-based ice sheets around the continent over time, and explore the links between AIS variability and global sea level. By comparing north–south variations across the Scotia Sea be- tween the Pirie Basin (Site U1538) and the Dove Basin (Sites U1536 and U1537), Expedition 382 will also deliver critical information on how climate changes in the Southern Ocean affect ocean circulation through the Drake Passage, meridional overturning in the region, water mass production, ocean–atmosphere CO2 transfer by wind- induced upwelling, sea ice variability, bottom water outflow from the Weddell Sea, Antarctic weathering inputs, and changes in oceanic and atmospheric fronts in the vicinity of the ACC. Comparing changes in dust proxy records between the Scotia Sea and Antarctic ice cores will also provide a detailed reconstruction of changes in the Southern Hemisphere westerlies on millennial and orbital timescales for the last 800 ky. Extending the ocean dust record beyond the last 800 ky will help to evaluate dust-climate couplings since the Pliocene, the potential role of dust in iron fertilization and atmospheric CO2 drawdown during glacials, and whether dust input to Antarctica played a role in the MPT. The principal scientific objective of Subantarctic Front Sites U1534 and U1535 at the northern limit of the Scotia Sea is to recon- struct and understand how ocean circulation and intermediate water formation responds to changes in climate with a special focus on the connectivity between the Atlantic and Pacific basins, the “cold water route.” The Subantarctic Front contourite drift, deposited between 400 and 2000 m water depth on the northern flank of an east–west trending trough off the Chilean continental shelf, is ideally situated to monitor millennial- to orbital-scale variability in the export of Antarctic Intermediate Water beneath the Subantarctic Front. During Expedition 382, we recovered continuously deposited sediments from this drift spanning the late Pleistocene (from ~0.78 Ma to recent) and from the late Pliocene (~3.1–2.6 Ma). These sites are expected to yield a wide array of paleoceanographic records that can be used to interpret past changes in the density structure of the Atlantic sector of the Southern Ocean, track migrations of the Sub- antarctic Front, and give insights into the role and evolution of the cold water route over significant climate episodes, including the following: • The most recent warm interglacials of the late Pleistocene and • The intensification of Northern Hemisphere glaciation.National Science Foundatio

A Serious Disease of Groundnut Caused by Cowpea Mild Mottle Virus in the Sudan

A disease of groundnut characterized by stunting, downward rolling, mottling, general chlorosis and reduced leaflet size occurred in the Sudan. During 1992-94, surveys showed that the disease was restricted to irrigated groundnut crops grown between the 2 Niles. The viral causal agent had slightly flexuous filamentous particles (626 nm long) and was transmitted by whiteflies. It was identified serologically as cowpea mild mottle carlavirus (CPMMV). This appears to be the first record of natural occurrence of CPMMV on groundnut in the Sudan

Inflammatory and Immunological parameters in adults with Down syndrome

<p>Abstract</p> <p>Background</p> <p>The increase in life expectancy within the general population has resulted in an increasing number of elderly adults, including patients with Down syndrome (DS), with a current life expectancy of about 50 years. We evaluate the parameters of humoral and cellular immune response, the quantitative expression of the regulator of calcineurin1 gene (RCAN1) and the production of cytokines. The study group consisted of adults DS (n = 24) and a control group with intellectual disability without Down syndrome (ID) (n = 21) and living in a similar environmental background. It was evaluated serology, immunophenotyping, the quantitative gene expression of RCAN1 and the production of cytokines.</p> <p>Results</p> <p>In the DS group, the results showed an increase in NK cells, CD8, decreased CD19 (p < 0.05) and an increase spontaneous production of IFNgamma, TNFalpha and IL-10 (p < 0.05). There was not any difference in RCAN1 gene expression between the groups.</p> <p>Conclusions</p> <p>These data suggest a similar humoral response in the two groups. The immunophenotyping suggests sign of premature aging of the immune system and the cytokine production show a proinflammatory profile.</p

Mechanism of nitrogen metabolism-related parameters and enzyme activities in the pathophysiology of autism

<p>Abstract</p> <p>Background</p> <p>There is evidence that impaired metabolism play an important role in the etiology of many neuropsychiatric disorders. Although this has not been investigated to date, several recent studies proposed that nitrogen metabolism-related parameters may have a pathophysiological role in autism.</p> <p>Methods</p> <p>The study enrolled 20 Saudi boys with autism aged 4 to 12 years and 20 healthy controls matched for age and gender. Levels of creatine, urea, ammonia, gamma-aminobutyric acid (GABA), glutamate:glutamine (Glu:Gln) ratio, and enzymatic activities of glutamate dehydrogenase, 5'-nucleotidase, and adenosine deaminase (ADA) were determined in plasma samples from both groups.</p> <p>Results</p> <p>We found a significant elevation of creatine, 5'-nucleotidase, GABA, and glutamic acid and a significant decrease in the enzymatic activity of ADA and glutamine level in patients with autism compared with healthy controls. The most significant variation between the two groups was found in the Glu:Gln ratio.</p> <p>Conclusion</p> <p>A raised Glu:Gln ratio together with positive correlations in creatine, GABA, and 5'-nucleotidase levels could contribute to the pathophysiology of autism, and might be useful diagnostic markers. The mechanism through which these parameters might be related to autism is discussed in detail.</p