A novel potassium channel antagonist has been purified from the defensive mucus secreted by Calliostoma canaliculatum, a marine snail found in the temperate coastal waters of the western Pacific. The ...toxin is expelled from the hypobranchial gland as part of a defensive response and is contained within a viscous matrix that minimizes dilution and degradation. The active compound was isolated by multistage microbore HPLC separations followed by bioactivity assays. Nuclear magnetic resonance, combined with electrospray ionization Fourier-transform ion cyclotron resonance and electrospray ionization ion trap mass spectrometry indicate that the active component is a heretofore unknown indole-derivative, a disulfide-linked dimer of 6-bromo-2-mercaptotryptamine (BrMT). Exudates from the hypobranchial glands of various marine mollusks have been sources for dye compounds such as 6–6 dibromoindigo, the ancient dye Tyrian purple. BrMT represents the first correlation of a hypobranchial gland exudate with a molecular response. Voltage clamp experiments with a number of K channel subtypes indicate that BrMT inhibits certain voltage-gated K channels of the Kv1 subfamily.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract only
1562
Background: The incidence of ductal carcinoma in situ (DCIS) has dramatically increased with widespread mammographic screening. Although risk of recurrence of DCIS is low, it is ...associated with a higher risk for subsequent contralateral breast cancer (CBC), for which preventive measures are available. We evaluated the uptake of surgical and pharmacologic interventions to reduce CBC risk at our institution and investigated factors that may influence treatment choices for DCIS. Methods: City of Hope (COH) DCIS patients were identified using two sources, the Circulating Breast Tumor Marker (BrTM) Registry and the National Comprehensive Cancer Network (NCCN) database. Datasets were linked together, and treatment variables were cross-tabulated with patient and tumor characteristics. Results: Of 782 patients with breast malignancy diagnosed since 1997, 370 were excluded due to concurrent or prior invasive disease, 8 due to suspected misclassification based on therapies received, and 4 due to treatment on protocol. Of the remaining pure DCIS patients, treatment choices were recorded for 289. Of those, 40 (14%) chose bilateral risk reduction mastectomy (BRRM), 82 (28%) unilateral mastectomy, 165 (57%) lumpectomy, and 2 had no surgery. Hormonal therapy (HT) was recorded for 215 individuals who did not pursue BRRM: 124 (57%) took tamoxifen, 3 of whom switched to raloxifene, 5 (2%) started with raloxifene, and 7 (3%) took an unspecified hormonal agent, for a total HT uptake of 55%. This included 8 of 29 women with ER-negative DCIS who chose HT for CBC risk reduction. Younger age at diagnosis was associated with BRRM (24% of women diagnosed before age 50, 10% of those diagnosed 50-64, and 5% of women 65+ had BRRM, p<0.001) and HT (59% of women <65 chose HT compared to 40% of women 65+, p=0.009). Within ethnic minorities, more Asian women chose BRRM (22% vs 7% of other minorities, p=0.08). Interestingly, fewer high grade DCIS women opted for HT (39% vs 55% for low to intermediate grade, p=0.06). Conclusions: Young women tend to pursue surgical prophylaxis. Among women who keep their breasts, HT uptake was high across all age and ethnic groups, except for those older than 65 at diagnosis. It is unclear if this is due to patient choice or reflects age bias in physician recommendation.
An approach for genome analysis based on sequencing and assembly of unselected pieces of DNA from the whole chromosome has been applied to obtain the complete nucleotide sequence (1,830, 137 base ...pairs) of the genome from the bacterium Haemophilus influenzae Rd. This approach eliminates the need for initial mapping efforts and is therefore applicable to the vast array of microbial species for which genome maps are unavailable. The H. influenzae Rd genome sequence (Genome Sequence DataBase accession number L42023) represents the only complete genome sequence from a free-living organism.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
46.
The Minimal Gene Complement of Mycoplasma genitalium Fraser, Claire M.; Gocayne, Jeannine D.; White, Owen ...
Science (American Association for the Advancement of Science),
10/1995, Volume:
270, Issue:
5235
Journal Article
Peer reviewed
The complete nucleotide sequence (580,070 base pairs) of the Mycoplasma genitalium genome, the smallest known genome of any free-living organism, has been determined by whole-genome random sequencing ...and assembly. A total of only 470 predicted coding regions were identified that include genes required for DNA replication, transcription and translation, DNA repair, cellular transport, and energy metabolism. Comparison of this genome to that of Haemophilus influenzae suggests that differences in genome content are reflected as profound differences in physiology and metabolic capacity between these two organisms.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
We present the serendipitous discovery of a galaxy group in the XMM-LSS field with MIGHTEE Early Science observations. Twenty galaxies are detected in HI in this \(z\sim0.044\) group, with a ...\(3\sigma\) column density sensitivity of \(N_\mathrm{HI} = 1.6\times10^{20}\,\mathrm{cm}^{-2}\). This group has not been previously identified, despite residing in a well-studied extragalactic legacy field. We present spatially-resolved HI total intensity and velocity maps for each of the objects, which reveal environmental influence through disturbed morphologies. The group has a dynamical mass of \(\log_{10}(M_\mathrm{dyn}/\mathrm{M}_\odot) = 12.32\), and is unusually gas-rich, with an HI-to-stellar mass ratio of \(\log_{10}(f_\mathrm{HI}^\mathrm{*}) = -0.2\), which is 0.7 dex greater than expected. The group's high HI content, spatial, velocity, and identified galaxy type distributions strongly suggest that it is in the early stages of its assembly. The discovery of this galaxy group is an example of the importance of mapping spatially-resolved HI in a wide range of environments, including galaxy groups. This scientific goal has been dramatically enhanced by the high sensitivity, large field-of-view, and wide instantaneous bandwidth of the MeerKAT telescope.
In an effort to identify new genes and analyse their expression patterns, 174,472 partial complementary DNA sequences (expressed sequence tags (ESTs)), totalling more than 52 million nucleotides of ...human DNA sequence, have been generated from 300 cDNA libraries constructed from 37 distinct organs and tissues. These ESTs have been combined with an additional 118,406 ESTs from the database dbEST, for a total of 83 million nucleotides, and treated as a shotgun sequence assembly project. The assembly process yielded 29,599 distinct tentative human consensus (THC) sequences and 58,384 non-overlapping ESTs. Of these 87,983 distinct sequences, 10,214 further characterize previously known genes based on statistically significant similarity to sequences in the available databases; the remainder identify previously unknown genes. Thirty tissues were sampled by over 1,000 ESTs each; only eight genes were matched by ESTs from all 30 tissues, and 227 genes were represented in 20 or more of the tissues sampled with more than 1,000 ESTs. Approximately 40% of identified human genes appear to be associated with basic energy metabolism, cell structure, homeostasis and cell division, 22% with RNA and protein synthesis and processing, and 12% with cell signalling and communication.
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