528 research outputs found
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Gene expression differs in susceptible and resistant amphibians exposed to Batrachochytrium dendrobatidis.
Chytridiomycosis, the disease caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), has devastated global amphibian biodiversity. Nevertheless, some hosts avoid disease after Bd exposure even as others experience near-complete extirpation. It remains unclear whether the amphibian adaptive immune system plays a role in Bd defence. Here, we describe gene expression in two host species-one susceptible to chytridiomycosis and one resistant-following exposure to two Bd isolates that differ in virulence. Susceptible wood frogs (Rana sylvatica) had high infection loads and mortality when exposed to the more virulent Bd isolate but lower infection loads and no fatal disease when exposed to the less virulent isolate. Resistant American bullfrogs (R. catesbeiana) had high survival across treatments and rapidly cleared Bd infection or avoided infection entirely. We found widespread upregulation of adaptive immune genes and downregulation of important metabolic and cellular maintenance components in wood frogs after Bd exposure, whereas American bullfrogs showed little gene expression change and no evidence of an adaptive immune response. Wood frog responses suggest that adaptive immune defences may be ineffective against virulent Bd isolates that can cause rapid physiological dysfunction. By contrast, American bullfrogs exhibited robust resistance to Bd that is likely attributable, at least in part, to their continued upkeep of metabolic and skin integrity pathways as well as greater antimicrobial peptide expression compared to wood frogs, regardless of exposure. Greater understanding of these defences will ultimately help conservationists manage chytridiomycosis
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Intestinal Parasites in an Ottoman Period Latrine from Acre (Israel) Dating to the Early 1800s CE.
The aim of this study is to determine the species of parasites that affected the inhabitants of the city of Acre on the coast of the eastern Mediterranean during the Ottoman Period. This is the first archaeological study of parasites in the Ottoman Empire. We analysed sediment from a latrine dating to the early 1800s for the presence of helminth eggs and protozoan parasites which caused dysentery. The samples were examined using light microscopy and enzyme-linked immunosorbent assay (ELISA) kits. We found evidence for roundworm (Ascaris lumbricoides), whipworm (Trichuris trichiura), fish tapeworm (Dibothriocephalus sp.), Taenia tapeworm (Taenia sp.), lancet liver fluke (Dicrocoelium dendriticum), and the protozoa Giardia duodenalis and Entamoeba histolytica. The parasite taxa recovered demonstrate the breadth of species present in this coastal city. We consider the effect of Ottoman Period diet, culture, trade and sanitation upon risk of parasitism in this community living 200 years ago
Intercollegiate Women\u27s Choral Festival
KSU School of Music presents Intercollegiate Women\u27s Choral Festival.https://digitalcommons.kennesaw.edu/musicprograms/1097/thumbnail.jp
Hyperbaric oxygen improves engraftment of ex-vivo expanded and gene transduced human CD34+ cells in a murine model of umbilical cord blood transplantation
Delayed engraftment and graft failure represent major obstacles to successful umbilical cord blood (UCB) transplantation. Herein, we evaluated the use of hyperbaric oxygen (HBO) therapy as an intervention to improve human UCB stem/progenitor cell engraftment in an immune deficient mouse model. Six-to eight-week old NSG mice were sublethally irradiated 24 hours prior to CD34+ UCB cell transplant. Irradiated mice were separated into a non-HBO group (where mice remained under normoxic conditions) and the HBO group (where mice received two hours of HBO therapy; 100% oxygen at 2.5 atmospheres absolute). Four hours after completing HBO therapy, both groups intravenously received CD34+ UCB cells that were transduced with a lentivirus carrying luciferase gene and expanded for in vivo imaging. Mice were imaged and then sacrificed at one of 10 times up to 4.5 months post-transplant. HBO treated mice demonstrated significantly improved bone marrow, peripheral blood , and spleen (p=0.0293) retention and subsequent engraftment. In addition, HBO significantly improved peripheral, spleen and bone marrow engraftment of human myeloid and B-cell subsets. In vivo imaging demonstrated that HBO mice had significantly higher ventral and dorsal bioluminescence values. These studies suggest that HBO treatment of NSG mice prior to UCB CD34+ cell infusion significantly improves engraftment
Mutational analysis of the major soybean UreF paralogue involved in urease activation
The soybean genome duplicated ∼14 and 45 million years ago and has many paralogous genes, including those in urease activation (emplacement of Ni and CO2 in the active site). Activation requires the UreD and UreF proteins, each encoded by two paralogues. UreG, a third essential activation protein, is encoded by the single-copy Eu3, and eu3 mutants lack activity of both urease isozymes. eu2 has the same urease-negative phenotype, consistent with Eu2 being a single-copy gene, possibly encoding a Ni carrier. Unexpectedly, two eu2 alleles co-segregated with missense mutations in the chromosome 2 UreF paralogue (Ch02UreF), suggesting lack of expression/function of Ch14UreF. However, Ch02UreF and Ch14UreF transcripts accumulate at the same level. Further, it had been shown that expression of the Ch14UreF ORF complemented a fungal ureF mutant. A third, nonsense (Q2*) allelic mutant, eu2-c, exhibited 5- to 10-fold more residual urease activity than missense eu2-a or eu2-b, though eu2-c should lack all Ch02UreF protein. It is hypothesized that low-level activation by Ch14UreF is ‘spoiled’ by the altered missense Ch02UreF proteins (‘epistatic dominant-negative’). In agreement with active ‘spoiling’ by eu2-b-encoded Ch02UreF (G31D), eu2-b/eu2-c heterozygotes had less than half the urease activity of eu2-c/eu2-c siblings. Ch02UreF (G31D) could spoil activation by Chr14UreF because of higher affinity for the activation complex, or because Ch02UreF (G31D) is more abundant than Ch14UreF. Here, the latter is favoured, consistent with a reported in-frame AUG in the 5' leader of Chr14UreF transcript. Translational inhibition could represent a form of ‘functional divergence’ of duplicated genes
Development and characterization of a novel C-terminal inhibitor of Hsp90 in androgen dependent and independent prostate cancer cells
Background: The molecular chaperone, heat shock protein 90 (Hsp90) has been shown to be overexpressed in a
number of cancers, including prostate cancer, making it an important target for drug discovery. Unfortunately,
results with N-terminal inhibitors from initial clinical trials have been disappointing, as toxicity and resistance
resulting from induction of the heat shock response (HSR) has led to both scheduling and administration concerns.
Therefore, Hsp90 inhibitors that do not induce the heat shock response represent a promising new direction for
the treatment of prostate cancer. Herein, the development of a C-terminal Hsp90 inhibitor, KU174, is described,
which demonstrates anti-cancer activity in prostate cancer cells in the absence of a HSR and describe a novel
approach to characterize Hsp90 inhibition in cancer cells.
Methods: PC3-MM2 and LNCaP-LN3 cells were used in both direct and indirect in vitro Hsp90 inhibition assays
(DARTS, Surface Plasmon Resonance, co-immunoprecipitation, luciferase, Western blot, anti-proliferative, cytotoxicity
and size exclusion chromatography) to characterize the effects of KU174 in prostate cancer cells. Pilot in vivo
efficacy studies were also conducted with KU174 in PC3-MM2 xenograft studies.
Results: KU174 exhibits robust anti-proliferative and cytotoxic activity along with client protein degradation and
disruption of Hsp90 native complexes without induction of a HSR. Furthermore, KU174 demonstrates direct binding
to the Hsp90 protein and Hsp90 complexes in cancer cells. In addition, in pilot in-vivo proof-of-concept studies
KU174 demonstrates efficacy at 75 mg/kg in a PC3-MM2 rat tumor model.
Conclusions: Overall, these findings suggest C-terminal Hsp90 inhibitors have potential as therapeutic agents for
the treatment of prostate cancer
Modeling the System Parameters of 2M1533+3759: A New Longer-Period Low-Mass Eclipsing sdB+dM Binary
We present new photometric and spectroscopic observations for 2M 1533+3759 (=
NSVS 07826147). It has an orbital period of 0.16177042 day, significantly
longer than the 2.3--3.0 hour periods of the other known eclipsing sdB+dM
systems. Spectroscopic analysis of the hot primary yields Teff = 29230 +/- 125
K, log g = 5.58 +/- 0.03 and log N(He)/N(H) = -2.37 +/- 0.05. The sdB velocity
amplitude is K1 = 71.1 +/- 1.0 km/s. The only detectable light contribution
from the secondary is due to the surprisingly strong reflection effect. Light
curve modeling produced several solutions corresponding to different values of
the system mass ratio, q(M2/M1), but only one is consistent with a core helium
burning star, q=0.301. The orbital inclination is 86.6 degree. The sdB primary
mass is M1 = 0.376 +/- 0.055 Msun and its radius is R1 = 0.166 +/- 0.007 Rsun.
2M1533+3759 joins PG0911+456 (and possibly also HS2333+3927) in having an
unusually low mass for an sdB star. SdB stars with masses significantly lower
than the canonical value of 0.48 Msun, down to as low as 0.30 Msun, were
theoretically predicted by Han et al. (2002, 2003), but observational evidence
has only recently begun to confirm the existence of such stars. The existence
of core helium burning stars with masses lower than 0.40--0.43 Msun implies
that at least some sdB progenitors have initial main sequence masses of
1.8--2.0 Msun or more, i.e. they are at least main sequence A stars. The
secondary is a main sequence M5 star.Comment: 47 pages, 7 figure
Quantification of juvenile hormone III, vitellogenin, and vitellogenin-mRNA during the oviposition cycle of the lubber grasshopper
Abstract The vitellogenic cycle of the lubber grasshopper (Romalea microptera) was studied by measuring levels of juvenile hormone (JH III), vitellogenin, and vitellogenin-mRNA through the first oviposition cycle. JH III and vitellogenin were measured by radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA), respectively. To measure vitellogenin-mRNA, a partial (753 bp) cDNA fragment of vitellogenin was isolated from the fat body of vitellogenic animals. The sequence of this cDNA was related to vitellogenin sequences in other insect species. Using these sequence data, an RT-PCR (reverse transcriptase polymerase chain reaction) assay was developed to quantify vitellogenin-mRNA levels during the oviposition cycle. Vitellogenin-mRNA levels in the fat body tissue from virgin females were measured on specific days after eclosion and compared to hemolymph levels of JH III and vitellogenin from the same individuals. The levels of all three compounds (JH III, vitellogenin, and vitellogenin-mRNA) showed similar changes throughout the oviposition cycle, being undetectable or nearly undetectable initially (day 3), rising to maximum levels on days 23 and 28, and then dropped to lower or undetectable levels on the day of oviposition. The ability to measure these characteristics will be useful for studying the effects of hormonal and nutritional manipulations on reproduction
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A Search for Dark Higgs Bosons
Recent astrophysical and terrestrial experiments have motivated the proposal
of a dark sector with GeV-scale gauge boson force carriers and new Higgs
bosons. We present a search for a dark Higgs boson using 516 fb-1 of data
collected with the BABAR detector. We do not observe a significant signal and
we set 90% confidence level upper limits on the product of the Standard
Model-dark sector mixing angle and the dark sector coupling constant.Comment: 7 pages, 5 postscript figures, published version with improved plots
for b/w printin
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