52 research outputs found
Riesz transform characterization of Hardy spaces associated with Schr\"odinger operators with compactly supported potentials
Let L=-\Delta+V be a Schr\"odinger operator on R^d, d\geq 3. We assume that V
is a nonnegative, compactly supported potential that belongs to L^p(R^d), for
some p>d/2. Let K_t be the semigroup generated by -L. We say that an
L^1(R^d)-function f belongs to the Hardy space H_L^1 associated with L if
sup_{t>0} |K_t f| belongs to L^1(R^d). We prove that f\in H_L^1 if and only if
R_j f \in L^1(R^d) for j=1,...,d, where R_j= \frac{d}{dx_j} L^{-1/2} are the
Riesz transforms associated with L.Comment: 6 page
Synthesis and preliminary assessment of the anticancer and Wnt/β-catenin inhibitory activity of small amide libraries of fenamates and profens
As part of an ongoing program to study the anticancer activity of non-steroidal anti-inflammatory drugs (NSAIDs) through generating diversity libraries of multiple NSAID scaffolds, we synthesized a series of NSAID amide derivatives and screened these sets against three cancer cell lines (prostate, colon and breast) and Wnt/β-catenin signaling. The evaluated amide analog libraries show significant anticancer activity/cell proliferation inhibition, and specific members of the sets show inhibition of Wnt/β-catenin signaling.</p
Identification of Simplified Microbial Communities That Inhibit Clostridioides difficile Infection through Dilution/Extinction
The gastrointestinal microbiome plays an important role in limiting susceptibility to infection with Clostridioides difficile. To better understand the ecology of bacteria important for C. difficile colonization resistance, we developed an experimental platform to simplify complex communities of fecal bacteria through dilution and rapidly screen for their ability to resist C. difficile colonization after challenge, as measured by 100-fold reduction in levels of C. difficile in challenged communities. We screened 76 simplified communities diluted from cultures of six fecal donors and identified 24 simplified communities that inhibited C. difficile colonization in vitro. Sequencing revealed that simplified communities were composed of 19 to 67 opera- tional taxonomic units (OTUs) and could be partitioned into four distinct community types. One simplified community could be further simplified from 56 to 28 OTUs through dilution and retain the ability to inhibit C. difficile. We tested the efficacy of seven simplified communities in a humanized microbiota mouse model. We found that four communities were able to significantly reduce the severity of the initial C. difficile infection and limit susceptibility to disease relapse. Analysis of fecal microbiomes from treated mice demonstrated that simplified communities accelerated recovery of indigenous bacteria and led to stable engraftment of 19 to 22 OTUs from simplified communities. Overall, the insights gained through the identification and characterization of these simplified communities increase our understanding of the microbial dynamics of C. difficile infection and recovery
Die Thrombozytenaggregation nach vaginaler Hysterektomie unter kombinierter Thromboembolieprophylaxe mit Macrodex<sup>®</sup> 6 % und Sintrom<sup>®</sup>
Bei 25 wegen Descensus vaginae et uteri vaginal hysterektomierten und kolporrhaphierten Frauen wurde unter Frühund Spätthromboembolieprophylaxe (Macrodex® 6% 500 ml intraoperativ und Sintrom® ab dem 1. postoperativen Tag) die ADP- und Kollagen-induzierte Thrombozytenaggregation untersucht und statistisch überprüft. Die Aggregabilität der Thrombozyten nimmt unabhängig von der Konzentration und der Art des im Aggregationstest zugefügten Agens nach Dextran-60-.Gabe um die Hälfte 2 Stunden postoperativ ab und halt bis zum 1. postoperativen Tag an. Die Ausgangswerte werden um den 4. postoperativen Tag wieder erreicht. Die Desaggregationsge-schwindigkeit und -stärke weisen ein umgekehrtes Verhalten auf. Eine Abhängigkeit vom Alter und von der Zyklusphase (Proliferationsphase, Sekretionsphase und Postmenopause) lieβ sich nicht finden. Bei der Durchführung dieser kombinierten Thromboembolieprophylaxe erscheint ein ausreichender Schutz sowohl der intraals auch der postoperativen Gefährdungsphase gegeben.</jats:p
Identification of Simplified Microbial Communities That Inhibit Clostridioides difficile Infection through Dilution/Extinction
The gastrointestinal microbiome plays an important role in limiting susceptibility to infection with Clostridioides difficile. To better understand the ecology of bacteria important for C. difficile colonization resistance, we developed an experimental platform to simplify complex communities of fecal bacteria through dilution and rapidly screen for their ability to resist C. difficile colonization after challenge, as measured by 100-fold reduction in levels of C. difficile in challenged communities. We screened 76 simplified communities diluted from cultures of six fecal donors and identified 24 simplified communities that inhibited C. difficile colonization in vitro. Sequencing revealed that simplified communities were composed of 19 to 67 opera- tional taxonomic units (OTUs) and could be partitioned into four distinct community types. One simplified community could be further simplified from 56 to 28 OTUs through dilution and retain the ability to inhibit C. difficile. We tested the efficacy of seven simplified communities in a humanized microbiota mouse model. We found that four communities were able to significantly reduce the severity of the initial C. difficile infection and limit susceptibility to disease relapse. Analysis of fecal microbiomes from treated mice demonstrated that simplified communities accelerated recovery of indigenous bacteria and led to stable engraftment of 19 to 22 OTUs from simplified communities. Overall, the insights gained through the identification and characterization of these simplified communities increase our understanding of the microbial dynamics of C. difficile infection and recovery
Identification of Simplified Microbial Communities That Inhibit Clostridioides difficile Infection through Dilution/Extinction
ABSTRACT The gastrointestinal microbiome plays an important role in limiting susceptibility to infection with Clostridioides difficile. To better understand the ecology of bacteria important for C. difficile colonization resistance, we developed an experimental platform to simplify complex communities of fecal bacteria through dilution and rapidly screen for their ability to resist C. difficile colonization after challenge, as measured by >100-fold reduction in levels of C. difficile in challenged communities. We screened 76 simplified communities diluted from cultures of six fecal donors and identified 24 simplified communities that inhibited C. difficile colonization in vitro. Sequencing revealed that simplified communities were composed of 19 to 67 operational taxonomic units (OTUs) and could be partitioned into four distinct community types. One simplified community could be further simplified from 56 to 28 OTUs through dilution and retain the ability to inhibit C. difficile. We tested the efficacy of seven simplified communities in a humanized microbiota mouse model. We found that four communities were able to significantly reduce the severity of the initial C. difficile infection and limit susceptibility to disease relapse. Analysis of fecal microbiomes from treated mice demonstrated that simplified communities accelerated recovery of indigenous bacteria and led to stable engraftment of 19 to 22 OTUs from simplified communities. Overall, the insights gained through the identification and characterization of these simplified communities increase our understanding of the microbial dynamics of C. difficile infection and recovery. IMPORTANCE Clostridioides difficile is the leading cause of antibiotic-associated diarrhea and a significant health care burden. Fecal microbiota transplantation is highly effective at treating recurrent C. difficile disease; however, uncertainties about the undefined composition of fecal material and potential long-term unintended health consequences remain. These concerns have motivated studies to identify new communities of microbes with a simpler composition that will be effective at treating disease. This work describes a platform for rapidly identifying and screening new simplified communities for efficacy in treating C. difficile infection. Four new simplified communities of microbes with potential for development of new therapies to treat C. difficile disease are identified. While this platform was developed and validated to model infection with C. difficile, the underlying principles described in the paper could be easily modified to develop therapeutics to treat other gastrointestinal diseases
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