Site-specific aflatoxin B₁ adduction of sequence-positioned nucleosome core particles

The question of how the presence of nucleosomal packing of DNA modifies carcinogen interaction at specific sites cannot be answered by studies on whole chromatin or bulk nucleosomes because of the heterogeneity of DNA sequences in the particles. This problem was circumvented by constructing nucleosomes that are homogenous in DNA-histone contact points. A cloned DNA fragment, containing a sea urchin 5S gene which precisely positions a histone octamer was employed. By using 32P end-labeled DNA and genotoxins that allow cleavage at sites of attack, the frequency of adduction at every susceptible nucleotide can be determined on sequencing gels. The small methylating agent dimethyl sulfate (DMS) and the bulky alkylating agent aflatoxin B₁- dichloride (AFB₁-C1₂) were used to probe the influence of DNA-histone interactions on DNA alkylation patterns in sequence-positioned core particles. I find DMS to bind equally to naked or nucleosomal DNA, in a quantitative 1:1 ratio. In contrast, AFB₁-C1₂ binding is globally suppressed 2.4-fold in nucleosomes, but the DNA is more accessible to AFB1-C1₂ adduction in regions near the particle boundary. I observe no other histone-imposed localized changes in AFB₁ -C1₂ sequence specificity. Further, sites of DNase I cleavage or proposed DNA bending show neither enhanced or reduced AFB₁-C1₂ adduction to N7-guanine. Since AFB₁-C1₂ binding sites lie in the major groove, nucleosomal DNA appears accessible to AFB₁-C1₂ at all points of analysis, but with an access which is uniformly restricted in the central 100 nucleotides of the core particle. The data available do not indicate further localized or sitespecific perturbations in DNA interactions with the two carcinogens studied

The Subduction experiment : mooring field program and data summary ; Sub 1 June 1991-February 1992 ; Sub 2 February 1992-October 1992 ; Sub 3 October 1992-June 1993

An array of five surface moorings carrying meteorological and oceanographic instrumentation was deployed for a period of two years beginning in June 1991 as part of an Office of Naval Research (ONR) funded Subduction experiment. Three eight month deployments were carried out. The five mooring locations were 18°N 34°W, 18°N 22°W, 25.5°N 29°W, 33°N 22°W and 33°N 34°W. Two Woods Hole Oceanographic Institution (WHOI) and three Scripps Institution of Oceanography (SIO) moorings collected oceanographic and meteorological data, using a 3-meter discus or 2-meter toroid buoy and multiple Vector Measuring Current Meters (VMCMs), an Acoustic Doppler Current Profiler (ADCP) and Brancker temperature recorders (tpods). The surface buoys carried a Vector Averaging Wind Recorder (VAWR) and, on four of the five moorings, an Improved Meteorological Recorder (IMET) which measured wind speed and wind direction, sea surface temperature, air temperature, short wave radiation, barometric pressure and relative humidity. The IMET also measured precipitation. The VMCMs, ADCP and tpods, placed at depths 1 m to 3500 m, measured oceanic velocities and temperatures. This report presents meteorological and oceanographic data from the WHOI Upper Ocean Processes Group (UOP) and the SIO Instrument and Development Group (lDG) instruments and contains summaries of the instruments used, their depths, mooring positions, mooring deployment and recovery times, and data return. Appendices contain information on supplementary Subduction data sets.Funding provided by the Office of Naval Research under Contract No. N00014-90-J-1490

Isolation and characterization of cidofovir resistant vaccinia viruses

© 2008 Becker et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

An Efficient Method for Generating Poxvirus Recombinants in the Absence of Selection

The use of selectable markers (ecogpt) and selection pressures to aid in detection of poxvirus (Vaccinia, VV) recombinants has been implicated in the unintended introduction of second site mutations. We have reinvestigated the use of the helper virus system described by Scheiflinger et al. [1] and adapted by Yao and Evans [2] which produces recombinants at a high frequency in the absence of any selection, at a rate of 6–100%. Our system uses fowlpox virus (FPV) as the infectious helper virus which in infected cells provides the enzymatic apparatus for transcription and replication of a purified, transfected VV genome and for recombination with a second transfected PCR generated DNA fragment. To optimize the system, a PCR DNA fragment was generated that contained poxvirus promoter driven gfp and lacZ genes inserted within the coding sequences of the viral thymidine kinase gene. This PCR fragment was co-transfected together with VV genomic DNA. Recombinant VV was identified by plaquing the mixture on cells non-permissive for FPV and selection of green fluorescent or LacZ positive recombinant vaccinia plaques. The system was optimized using FPV permissive cells (CEF) and non-permissive cells (A549, CV-1) for both the initial infection/transfection and the subsequent selection. Up to 70% of the progeny vaccinia virus contained the gfp/LacZ insertion. In order to test for the presence of FPV/VV intertypic recombinants or other unintended mutations, recombinant wtVV (RwtVV) was regenerated from the gfp/LacZ viruses and evaluated by RFLP analysis and pathogenesis in animals. While all RwtVVs were viable in cell culture, in many of the RwtVV isolates, RFLP differences were noted and while some recombinant viruses exhibited wild type behavior in mice, a wide range of virulence indicative of unintended changes suggests that mutants created by “rescue” systems require careful analysis particularly before use for in vivo studies employing animal models

The relationship between facility‐based delivery and maternal and neonatal mortality in Sub‐Saharan Africa

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135613/1/ijgo263.pd

The Ursinus Weekly, May 16, 1960

Spanish and French Clubs to hold banquets on May 17, 18 • German Club to elect new officers on May 19 at 7 p.m. • Emery, Haeussner are music heads • Spirit Committee presents awards • Beta Sigma Lambda sponsors annual dinner dance on May 6 • Annual WAA banquet to be held on May 19 at 6:30 p.m. • Newman Club to hold picnic • YM-YWCA select committee heads for next year • Big-little sister group to organize on May 16 • Omega Chi holds breakfast at Wagners\u27 home on May 7 • Lantern to be issued Thursday; Awards presented • Eleven junior advisors selected for 1960-61 • Dottie D\u27Agostino is elected new president of Phi Alpha Psi • Dave Emery is elected new president of Pi Nu Epsilon • Jill Carter is elected new IRC president at meeting • Janice Jones to present recital • New WSGA council meets on May 9 • Jeff Brown and Ron Miller selected new cheerleaders • Dr. Rice explains U.C. experiment at convention • ISC holds annual dessert for freshman women on Monday • Editorial: Ideals • Letters to the editor • Newman Club report • Surrender involves a sacrifice • African dances • Cricket team loses first game on Haverford turf • Ursinus netmen lose to Dickinson on Saturday • Trackmen defeat Washington team • Morgan wins two championships • Softball team defeats G-burg • Independents win IFC track meet on Saturday • Bears defeat Haverford to win ninth victoryhttps://digitalcommons.ursinus.edu/weekly/1364/thumbnail.jp

The Ursinus Weekly, May 2, 1960

Dormitories elect officers; Eikner is hall board head • May Day to be held Saturday • Co-captains and four new cheerleaders named • John Innes presents paper at intercollegiate meeting at LVC • ISC to hold annual dessert for frosh women on May 9 • Haverford professor to talk to U.C. students on Middle East • Carol Taney wins Alexander Award • Pre-med society to hold annual elections • Dr. Lachman talks at MSGA banquet • Habgood and Fernandez are new head waiters • Bell, book and candle to be presented on May 7 & 8 • Vern Morgan runs mile in 4:13.6 to set record • WSGA installs new officers on Apr. 27 • Air raid to be held tomorrow at 2 p.m. • Y retreat services led by Elston, Yost, Jones • Curtain Club members urged to vote for officers tomorrow • Father Louis Giorgi to address Newman Club on May 2 at 7 p.m. • Editorial: Evil • Who, me? • Pyewacket and the play • Coming thaw • WRUC: Collegeville, Pa. • Men\u27s tennis team defeated twice • Thinclads drop meet to Garnet • C. Heffelfinger reaches MSI final • Lacrosse team wins three games • U tossers capture two; Drummond drops first • John Gartner to head Beta Sig; Vannucci and Cook also elected • Carol Mallick is announced as Omega Chi\u27s new president • Delta Pi has orphans\u27 party; Welcomes six new members • Spanish Club members taught Spanish dances by Sandra Motta • Inter-frat council sets rules for IF track meet on May 14 • I.R.C. to hold meeting tonight; New officers will be elected • PSEA elects new officers; Picnic to be held May 10 • Dot Haggerty is elected new head of the Spirit Committee • Canterbury Club to hold picnic at county park on May 9https://digitalcommons.ursinus.edu/weekly/1362/thumbnail.jp

Intention to deliver in a healthcare facility and healthcare facility‐based delivery rates among women in Akwatia, Ghana

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135204/1/ijgo161.pd

A novel lineage of proteobacteria involved in formation of marine Fe-oxidizing microbial mat communities

© The Authors, 2007. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PLoS One 2 (2007): e667, doi:10.1371/journal.pone.0000667.For decades it has been recognized that neutrophilic Fe-oxidizing bacteria (FeOB) are associated with hydrothermal venting of Fe(II)-rich fluids associated with seamounts in the world's oceans. The evidence was based almost entirely on the mineralogical remains of the microbes, which themselves had neither been brought into culture or been assigned to a specific phylogenetic clade. We have used both cultivation and cultivation-independent techniques to study Fe-rich microbial mats associated with hydrothermal venting at Loihi Seamount, a submarine volcano. Using gradient enrichment techniques, two iron-oxidizing bacteria, strains PV-1 and JV-1, were isolated. Chemolithotrophic growth was observed under microaerobic conditions; Fe(II) and Fe0 were the only energy sources that supported growth. Both strains produced filamentous stalk-like structures composed of multiple nanometer sized fibrils of Fe-oxyhydroxide. These were consistent with mineralogical structures found in the iron mats. Phylogenetic analysis of the small subunit (SSU) rRNA gene demonstrated that strains PV-1 and JV-1 were identical and formed a monophyletic group deeply rooted within the Proteobacteria. The most similar sequence (85.3% similarity) from a cultivated isolate came from Methylophaga marina. Phylogenetic analysis of the RecA and GyrB protein sequences confirmed that these strains are distantly related to other members of the Proteobacteria. A cultivation-independent analysis of the SSU rRNA gene by terminal-restriction fragment (T-RF) profiling showed that this phylotype was most common in a variety of microbial mats collected at different times and locations at Loihi. On the basis of phylogenetic and physiological data, it is proposed that isolate PV-1T ( = 1ATCC BAA-1019: JCM 14766) represents the type strain of a novel species in a new genus, Mariprofundus ferrooxydans gen. nov., sp. nov. Furthermore, the strain is the first cultured representative of a new candidatus class of the Proteobacteria that is widely distributed in deep-sea environments, Candidatus ζ (zeta)-Proteobacteria cl. nov.Funding was provided to DE and CLM by the National Science Foundation (0348330) and to DE through the NASA Astobiology Institute