Profile of estrogen‐responsive genes in an estrogen‐specific mammary gland outgrowth model

Both ovarian and pituitary hormones are required for the pubertal development of the mouse mammary gland. Estradiol directs ductal elongation and branching, while progesterone leads to tertiary branching and alveolar development. The purpose of this investigation was to identify estrogen‐responsive genes associated with pubertal ductal growth in the mouse mammary gland in the absence of other ovarian hormones and at different stages of development. We hypothesized that the estrogen‐induced genes and their associated functions at early stages of ductal elongation would be distinct from those induced after significant ductal elongation had occurred. Therefore, ovariectomized prepubertal mice were exposed to 17β‐estradiol from two to 28 days, and mammary gland global gene expression analyzed by microarray analysis at various times during this period. We found that: (a) gene expression changes in our estrogen‐only model mimic those changes that occur in normal pubertal development in intact mice, (b) both distinct and overlapping gene profiles were observed at varying extents of ductal elongation, and (c) cell proliferation, the immune response, and metabolism/catabolism were the most common functional categories associated with mammary ductal growth. Particularly striking was the novel observation that genes active during carbohydrate metabolism were rapidly and robustly decreased in response to estradiol. Lastly, we identified mammary estradiol‐responsive genes that are also co‐expressed with estrogen receptor α in human breast cancer. In conclusion, our genomic data support the physiological observation that estradiol is one of the primary hormonal signals driving ductal elongation during pubertal mammary development. Mol. Reprod. Dev. 76: 733–750, 2009. Published 2009 Wiley‐Liss, Inc.     

Ectopic Expression of Vaccinia Virus E3 and K3 Cannot Rescue Ectromelia Virus Replication in Rabbit RK13 Cells

As a group, poxviruses have been shown to infect a wide variety of animal species. However, there is individual variability in the range of species able to be productively infected. In this study, we observed that ectromelia virus (ECTV) does not replicate efficiently in cultured rabbit RK13 cells. Conversely, vaccinia virus (VACV) replicates well in these cells. Upon infection of RK13 cells, the replication cycle of ECTV is abortive in nature, resulting in a greatly reduced ability to spread among cells in culture. We observed ample levels of early gene expression but reduced detection of virus factories and severely blunted production of enveloped virus at the cell surface. This work focused on two important host range genes, named E3L and K3L, in VACV. Both VACV and ECTV express a functional protein product from the E3L gene, but only VACV contains an intact K3L gene. To better understand the discrepancy in replication capacity of these viruses, we examined the ability of ECTV to replicate in wild-type RK13 cells compared to cells that constitutively express E3 and K3 from VACV. The role these proteins play in the ability of VACV to replicate in RK13 cells was also analyzed to determine their individual contribution to viral replication and PKR activation. Since E3L and K3L are two relevant host range genes, we hypothesized that expression of one or both of them may have a positive impact on the ability of ECTV to replicate in RK13 cells. Using various methods to assess virus growth, we did not detect any significant differences with respect to the replication of ECTV between wild-type RK13 compared to versions of this cell line that stably expressed VACV E3 alone or in combination with K3. Therefore, there remain unanswered questions related to the factors that limit the host range of ECTV.     

Indian Plant Germplasm on the Global Platter: An Analysis

Food security is a global concern amongst scientists, researchers and policy makers. No country is self-sufficient to address food security issues independently as almost all countries are inter-dependent for availability of plant genetic resources (PGR) in their national crop improvement programmes. Consultative Group of International Agricultural Research (CGIAR; in short CG) centres play an important role in conserving and distributing PGR through their genebanks. CG genebanks assembled the germplasm through collecting missions and acquisition the same from national genebanks of other countries. Using the Genesys Global Portal on Plant Genetic Resources, the World Information and Early Warning System (WIEWS) on Plant Genetic Resources for Food and Agriculture and other relevant databases, we analysed the conservation status of Indian-origin PGR accessions (both cultivated and wild forms possessed by India) in CG genebanks and other national genebanks, including the United States Department of Agriculture (USDA) genebanks, which can be considered as an indicator of Indian contribution to the global germplasm collection. A total of 28,027,770 accessions are being conserved world-wide by 446 organizations represented in Genesys; of these, 3.78% (100,607) are Indian-origin accessions. Similarly, 62,920 Indian-origin accessions (8.73%) have been conserved in CG genebanks which are accessible to the global research community for utilization in their respective crop improvement programmes. A total of 60 genebanks including 11 CG genebanks have deposited 824,625 accessions of PGR in the Svalbard Global Seed Vault (SGSV) as safety duplicates; the average number of accessions deposited by each genebank is 13,744, and amongst them there are 66,339 Indian-origin accessions. In principle, India has contributed 4.85 times the number of germplasm accessions to SGSV, in comparison to the mean value (13,744) of any individual genebank including CG genebanks. More importantly, about 50% of the Indian-origin accessions deposited in SGSV are traditional varieties or landraces with defined traits which form the backbone of any crop gene pool. This paper is also attempting to correlate the global data on Indian-origin germplasm with the national germplasm export profile. The analysis from this paper is discussed with the perspective of possible implications in the access and benefit sharing regime of both the International Treaty on Plant Genetic Resources for Food and Agriculture and the newly enforced Nagoya Protocol under the Convention on Biological Diversity.     

Mass Media and the Contagion of Fear: The Case of Ebola in America

Background

In the weeks following the first imported case of Ebola in the U. S. on September 29, 2014, coverage of the very limited outbreak dominated the news media, in a manner quite disproportionate to the actual threat to national public health; by the end of October, 2014, there were only four laboratory confirmed cases of Ebola in the entire nation. Public interest in these events was high, as reflected in the millions of Ebola-related Internet searches and tweets performed in the month following the first confirmed case. Use of trending Internet searches and tweets has been proposed in the past for real-time prediction of outbreaks (a field referred to as “digital epidemiology”), but accounting for the biases of public panic has been problematic. In the case of the limited U. S. Ebola outbreak, we know that the Ebola-related searches and tweets originating the U. S. during the outbreak were due only to public interest or panic, providing an unprecedented means to determine how these dynamics affect such data, and how news media may be driving these trends.

Methodology

We examine daily Ebola-related Internet search and Twitter data in the U. S. during the six week period ending Oct 31, 2014. TV news coverage data were obtained from the daily number of Ebola-related news videos appearing on two major news networks. We fit the parameters of a mathematical contagion model to the data to determine if the news coverage was a significant factor in the temporal patterns in Ebola-related Internet and Twitter data.

Conclusions

We find significant evidence of contagion, with each Ebola-related news video inspiring tens of thousands of Ebola-related tweets and Internet searches. Between 65% to 76% of the variance in all samples is described by the news media contagion model.     

Natural Helicobacter infection modulates mouse intestinal muscularis macrophage responses

Helicobacter species are common laboratory pathogens which induce intestinal inflammation and disease in susceptible mice. Since in vitro studies indicate that Helicobacter products activate macrophages, we hypothesized that in vivo Helicobacter infection regulates the inflammatory response of intestinal muscularis macrophages from C57Bl/6 mice. Helicobacter hepaticus infection increased surface expression of macrophage markers F4/80, CD11b and MHC-II within whole intestinal muscle mounts. However, constitutive cytokine and chemokine production by macrophages isolated from infected mice significantly decreased compared to macrophages from uninfected mice despite no detectable bacterial products in the cultures. In addition, muscularis macrophages from infected mice up-regulated FIZZ-1 and SK-1 gene expression, suggesting the macrophages had an anti-inflammatory phenotype. Corresponding with increased anti-inflammatory gene expression, macrophages from infected mice were more phagocytic but did not produce cytokines after stimulation with LPS and IFN-γ or immune complexes and IL-4. Therefore, the presence of Helicobacter infection matures intestinal muscularis macrophages, modulating the constitutive macrophage response to become more anti-inflammatory and resistant to secondary stimulation.     

Sperm competition in the Drosophila female

Summary Modified B ^S translocation males were developed at 26.0° C where univalentbearing gametes are recovered with less than half the frequency than at 18.0° C. Upon eclosion the males were stored for definite time periods at either temperature before mating individually to single y free-X females. the transfer cultures of the females show a higher frequency of recovery of univalent-bearing progeny regardless of the temperature or storage treatment of the male. In addition, postmeiotic temperature treatment does not appear to fundamentally alter the overall frequency of recovery of univalent-bearing gametes which is presumably determined by the developmental temperature of the male. A similar trend is observed for matings of y females to single X.Y^SY^L/O males in which the males were developed and stored at 26.0° C; namely, a higher frequency of recovery of attached-XY gametes in the transfer cultures.     

Structures of Mycobacterium tuberculosis 1-deoxy-D-xylulose-5-phosphate reductoisomerase provide new insights into catalysis

Isopentenyl diphosphate is the precursor of various isoprenoids that are essential to all living organisms. It is produced by the mevalonate pathway in humans but by an alternate route in plants, protozoa, and many bacteria. 1-deoxy-D-xylulose-5-phosphate reductoisomerase catalyzes the second step of this non-mevalonate pathway, which involves an NADPH-dependent rearrangement and reduction of 1-deoxy-D-xylulose 5-phosphate to form 2-C-methyl-D-erythritol 4-phosphate. The use of different pathways, combined with the reported essentiality of the enzyme makes the reductoisomerase a highly promising target for drug design. Here we present several high resolution structures of the Mycobacterium tuberculosis 1-deoxy-D-xylulose-5-phosphate reductoisomerase, representing both wild type and mutant enzyme in various complexes with Mn(2+), NADPH, and the known inhibitor fosmidomycin. The asymmetric unit corresponds to the biological homodimer. Although crystal contacts stabilize an open active site in the B molecule, the A molecule displays a closed conformation, with some differences depending on the ligands bound. An inhibition study with fosmidomycin resulted in an estimated IC(50) value of 80 nm. The double mutant enzyme (D151N/E222Q) has lost its ability to bind the metal and, thereby, also its activity. Our structural information complemented with molecular dynamics simulations and free energy calculations provides the framework for the design of new inhibitors and gives new insights into the reaction mechanism. The conformation of fosmidomycin bound to the metal ion is different from that reported in a previously published structure and indicates that a rearrangement of the intermediate is not required during catalysis.     

Augmented lipopolysaccharide-induced TNF-alpha production by peritoneal macrophages in type 2 diabetic mice is dependent on elevated glucose and requires p38 MAPK

Dysregulated inflammation is a complication of type 2 diabetes (T2D). In this study, we show that augmented LPS-induced TNF-alpha production by resident peritoneal macrophages (PerMphi) in type 2 diabetic (db/db) mice is dependent on elevated glucose and requires p38 MAPK. Intraperitoneal LPS administered to db/db and nondiabetic (db/+) mice induced 3- and 4-fold more TNF-alpha in the peritoneum and serum, respectively, of db/db mice as compared with db/+ mice. Examination of the TLR-4/MD2 complex and CD14 expression showed no difference between db/db and db/+ PerMphi. Ex vivo stimulation of PerMphi with LPS produced a similar 3-fold increase in TNF-alpha production in db/db PerMphi when compared with db/+ PerMphi. PerMphi isolated from db/+ mice incubated in high glucose (4 g/L) medium for 12 h produced nearly 2-fold more TNF-alpha in response to LPS than PerMphi incubated in normal glucose medium (1 g/L). LPS-dependent stimulation of PI3K activity, ERK1/2 activation, and p38 kinase activity was greater in PerMphi from db/db mice as compared with db/+ mice. Only inhibition of p38 kinase blocked LPS-induced TNF-alpha production in PerMphi from db/db mice. Taken together, these data indicate that augmented TNF-alpha production induced by LPS in macrophages during diabetes is due to hyperglycemia and increased LPS-dependent activation of p38 kinase.