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Reinforced concrete (RC) framed buildings dissipate the seismic energy through yielding of the reinforcing bars. This yielding jeopardizes the serviceability of these buildings as it results in residual lateral deformations. Superelastic Shape Memory Alloys (SMAs) can recover inelastic strains by stress removal. Since SMA is a costly material, this paper defines the required locations of SMA bars in a typical RC frame to optimize its seismic performance in terms of damage scheme and seismic residual deformations. The intensities of five earthquakes causing failure to a typical RC six-storey building are defined and used to evaluate seven SMA design alternatives. [ABSTRACT FROM AUTHOR]

Environmental microorganisms continue to serve as a major source of bioactive natural products (NPs) and as an inspiration for many other scaffolds in the toolbox of modern medicine. Nearly all microbial NP-inspired therapies can be traced to field expeditions to collect samples from the environment. Despite the importance of these expeditions in the search for new drugs, few studies have attempted to document the extent to which NPs or their corresponding production genes are distributed within a given environment. To gain insights into this, the geographic occurrence of NP ketosynthase (KS) and adenylation (A) domains was documented across 53 and 58 surface sediment samples, respectively, covering 59,590 square kilometers of Lake Huron. Overall, no discernible NP geographic distribution patterns were observed for 90,528 NP classes of nonribosomal peptides and polyketides detected in the survey. While each sampling location harbored a similar number of A domain operational biosynthetic units (OBUs), a limited overlap of OBU type was observed, suggesting that at the sequencing depth used in this study, no single location served as a NP "hotspot". These data support the hypothesis that there is ample variation in NP occurrence between sampling sites and suggest that extensive sample collection efforts are required to fully capture the functional chemical diversity of sediment microbial communities on a regional scale.

Despite decades of cultivating microorganisms for use in drug discovery, few attempts have been made to measure the extent to which common cultivation techniques have accessed existing chemical space. Metagenomic studies have shown that cultivable bacteria represent a fraction of those that exist in the environment, and that uncultivated populations in sediment have genes that encode for a high diversity of novel natural product (NP) biosynthetic enzymes. Quantifying these genes in both sediment and cultivatable bacterial populations allows us to assess how much diversity is present on nutrient agar and is critical to guiding the trajectory of future NP discovery platforms. Herein, we employed next-generation amplicon sequencing to assess the NP biosynthetic gene populations present in two Lake Huron sediment samples, and compared these with populations from their corresponding cultivatable bacteria. We highlight three findings from our study: (1) after cultivation, we recovered between 7.7% and 23% of three common types of NP biosynthetic genes from the original sediment population; (2) between 76.3% and 91.5% of measured NP biosynthetic genes from nutrient agar have yet to be characterized in known biosynthetic gene cluster databases, indicating that readily cultivatable bacteria harbor the potential to produce new NPs; and (3) even though the predominant taxa present on nutrient media represented some of the major producers of bacterial NPs, the sediment harbored a significantly greater pool of NP biosynthetic genes that could be mined for structural novelty, and these likely belong to taxa that typically have not been represented in microbial drug discovery libraries.

The potential of the diverse chemistries present in natural products (NP) for biotechnology and medicine remains untapped because NP databases are not searchable with raw data and the NP community has no way to share data other than in published papers. Although mass spectrometry (MS) techniques are well-suited to high-throughput characterization of NP, there is a pressing need for an infrastructure to enable sharing and curation of data. We present Global Natural Products Social Molecular Networking (GNPS; http://gnps.ucsd.edu), an open-access knowledge base for community-wide organization and sharing of raw, processed or identified tandem mass (MS/MS) spectrometry data. In GNPS, crowdsourced curation of freely available community-wide reference MS libraries will underpin improved annotations. Data-driven social-networking should facilitate identification of spectra and foster collaborations. We also introduce the concept of 'living data' through continuous reanalysis of deposited data.

Background: Complications of cirrhosis may persist after liver transplantation. When indicated, partial splenic embolization (PSE) is an alternative to splenectomy but can cause severe infection. The identification of modifiable risk factors when performing PSE in immunocompromised liver transplant recipients may help reduce the risk of severe infection., Methods: Data were collected retrospectively for all PSE performed after liver transplantation at a single institution and included demographics, etiology of liver disease, indication for PSE, vaccination status, laboratory findings, procedural details, extent and pattern of splenic infarction, hospital length-of-stay, readmissions, procedural complications, and mortality. Statistical analysis included 2-tailed t test, Fisher exact test, and Kaplan-Meier survival curves, with significance defined as P < .05., Results: Sixteen patients received 22 embolizations, with 11 patients undergoing a single session and 5 patients undergoing multiple sessions. Indications included hypersplenism, gastrointestinal hemorrhage, ascites, and autoimmune hemolytic anemia. PSE produced significant and sustained cell count increases, improved ascites, and controlled hemorrhage. Splenic abscess, septic shock, need for splenectomy, and PSE-related mortality were seen in the group with large confluent splenic infarction but not in peripheral/wedge-shaped infarction. Multiple-session PSE exclusively using particles for embolization correlated with the pattern of peripheral/wedge-shaped infarction and avoided severe infection and PSE-related mortality., Conclusions: PSE in the immunosuppressed liver transplant recipient is an effective alternative to splenectomy, but carries substantial infectious risk. The risk is decreased when PSE performed with polyvinyl alcohol particles results in a pattern of peripheral/wedge-shaped infarction, which correlates with smaller infarction volumes, favorable length-of-stay, and minimal risk of abscess, sepsis, and mortality., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background: Graft-versus-host disease (GVHD) is a rare, serious, fatal disease that occurs after orthotopic liver transplantation (OLT)., Case Report: We treated a 60-year-old man who underwent OLT owing to familial amyloidosis. The patient developed fever on postoperative day 16. The fever was persistent and did not respond to antibiotic therapy. Cultures and radiologic studies were done and excluded infection as a potential cause. On postoperative day 26, a skin rash appeared on his chest, accompanied by diarrhea and persistent fever. The rash spread all over the trunk, neck, and arms, but spared the palms of his hands and soles of his feet. In the meantime, his blood cell count revealed pancytopenia. Skin biopsy was done and showed interface lymphocytic infiltrate that are largely centered on the dermal-epidermal junction, is consistent with GVHD (this pattern of rash distribution is unique and different from the rash of GVHD after hematopoietic stem cell transplant, which is confined to palms of the hands and soles of the feet; Fig 1). The diagnosis was confirmed by colonoscopy and multiple forceps biopsies, which revealed extensive crypt loss. After hematology consultation, the patient was treated by withdrawal of all immunosuppressive therapy coupled with abatacept infusion. Abatacept is a chimeric protein that inhibits T-lymphocytes and is approved by the US Food and Drug Administration for the treatment of rheumatoid arthritis. Interestingly, after second dose of abatacept the patient showed marked clinical and laboratory improvement. The patient was discharged after 47 days in a stable condition., Conclusion: Because of the lack of a consensus for treatment of these patients, we report our experience with a male patient who had post-OLT GVHD and showed a marked improvement in response to abatacept., (Copyright © 2014 Elsevier Inc. All rights reserved.)