347 research outputs found

    Signals, Synapses, and Synthesis: How New Proteins Control Plasticity

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    Localization of mRNAs to dendrites and local protein synthesis afford spatial and temporal regulation of gene expression and endow synapses with the capacity to autonomously alter their structure and function. Emerging evidence indicates that RNA binding proteins, ribosomes, translation factors and mRNAs encoding proteins critical to synaptic structure and function localize to neuronal processes. RNAs are transported into dendrites in a translationally quiescent state where they are activated by synaptic stimuli. Two RNA binding proteins that regulate dendritic RNA delivery and translational repression are cytoplasmic polyadenylation element binding protein and fragile X mental retardation protein (FMRP). The fragile X syndrome (FXS) is the most common known genetic cause of autism and is characterized by the loss of FMRP. Hallmark features of the FXS include dysregulation of spine morphogenesis and exaggerated metabotropic glutamate receptor-dependent long term depression, a cellular substrate of learning and memory. Current research focuses on mechanisms whereby mRNAs are transported in a translationally repressed state from soma to distal process and are activated at synaptic sites in response to synaptic signals

    A phase I study of the oral gamma secretase inhibitor R04929097 in combination with gemcitabine in patients with advanced solid tumors (PHL-078/CTEP 8575)

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    PURPOSE: To establish the recommended phase II dose of the oral γ-secretase inhibitor RO4929097 (RO) in combination with gemcitabine; secondary objectives include the evaluation of safety, tolerability, pharmacokinetics, biomarkers of Notch signaling and preliminary anti-tumor activity. METHODS: Patients with advanced solid tumors were enrolled in cohorts of escalating RO dose levels (DLs). Tested RO DLs were 20 mg, 30 mg, 45 mg and 90 mg. RO was administered orally, once daily on days 1-3, 8-10, 15-17, 22-24. Gemcitabine was administered at 1,000 mg/m(2) on d1, 8, and 15 in 28 d cycles. Dose limiting toxicities (DLTs) were assessed by CTCAE v4. Serial plasma was collected for RO (total and unbound) and gemcitabine pharmacokinetic analysis. Biomarkers of Notch signaling were assessed by immunohistochemistry in archival tissue. Antitumor activity was evaluated (RECIST 1.1). RESULTS: A total of 18 patients were enrolled to establish the recommended phase II dose. Of these, 3 patients received 20 mg RO, 7 patients received 30 mg RO, 6 patients received 45 mg RO and 2 patients received 90 mg RO. DLTs were grade 3 transaminitis (30 mg RO), grade 3 transaminitis and maculopapular rash (45 mg RO), and grade 3 transaminitis and failure to receive 75 % of planned RO doses secondary to prolonged neutropenia (90 mg); all were reversible. The maximum tolerated dose was exceeded at 90 mg RO. Pharmacokinetic analysis of both total and free RO confirmed the presence of autoinduction at 45 and 90 mg. Median levels of Notch3 staining were higher in individuals who received fewer than 4 cycles (p = 0.029). Circulating angiogenic factor levels did not correlate with time to progression or ≥ grade 3 adverse events. Best response (RECIST 1.1) was partial response (nasopharyngeal cancer) and stable disease > 4 months was observed in 3 patients (pancreas, tracheal, and breast primary cancers). CONCLUSIONS: RO and gemcitabine can be safely combined. The recommended phase II dose of RO was 30 mg in combination with gemcitabine 1,000 mg/m(2). Although RO exposure was limited by the presence of autoinduction, RO levels achieved exceeded the area under the concentration-time curve for 0-24 h (AUC(0-24)) predicted for efficacy in preclinical models using daily dosing. Evidence of clinical antitumor activity and prolonged stable disease were identified

    Proposed initiative would study Earth's weathering engine

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94818/1/eost14765.pd

    The Grizzly, February 8, 1994

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    Ursinus Celebrates 125 Years of Academics • An Evaluation of the 128 Credit System • In Celebration of Black History Month: Al Eaton Brings on His One-Man Show • Ursinus Crimes Reported • Who Freed South Africa? • Guys Pledging Begins on Friday • Suite Etiquette • Senior Profile: Craig Faucher • Airband \u2794 • Come out and Support a U.C. Senior • Berman to Receive Preservation Grant • Woodward Exhibit on Display • Bright Moments to Perform • An Internal Compass Spinning • Eats & Seats • Wrestlers Up to 9-1 • Ursinus Gymnastics Sets New Records • Personal Interest Workshops to be Held • UC Student Almost Becomes Phillies\u27 Biggest Phanhttps://digitalcommons.ursinus.edu/grizzlynews/1329/thumbnail.jp

    HDMX-L is expressed from a functional P53-responsive promoter in the first intron of the HDMX gene, and participates in an auto-regulatory feedback loop to control P53 activity.

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    The p53 regulatory network is critically involved in preventing the initiation of cancer. In unstressed cells p53 is maintained at low levels and is largely inactive, mainly through the action of its two essential negative regulators, HDM2 and HDMX. p53 abundance and activity are upregulated in response to various stresses including DNA damage and oncogene activation. Active p53 initiates transcriptional and transcription-independent programs that result in cell cycle arrest, cellular senescence or apoptosis. p53 also activates transcription of HDM2, which initially leads to the degradation of HDMX, creating a positive feedback loop to obtain maximal activation of p53. Subsequently, when stress-induced post-translational modifications start to decline, HDM2 becomes effective in targeting p53 for degradation, thus attenuating the p53 response. To date, no clear function for HDMX in this critical attenuation phase has been demonstrated experimentally. Like HDM2, the HDMX gene contains a promoter (P2) in its first intron that is potentially inducible by p53. We show that p53 activation in response to a plethora of p53-activating agents induces the transcription of a novel HDMX mRNA transcript from the HDMX-P2 promoter. This mRNA is more efficiently translated than that expressed from the constitutive HDMX-P1 promoter, and it encodes a long form of HDMX protein, HDMX-L. Importantly, we demonstrate that HDMX-L cooperates with HDM2 to promote the ubiquitination of p53, and that p53-induced HDMX transcription from the P2 promoter can play a key role in the attenuation phase of the p53-response, to effectively diminish p53 abundance as cells recover from stress

    Blood Transfusion Management for Patients Treated With Anti-CD38 Monoclonal Antibodies

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    Daratumumab has proven to be highly efficacious for relapsed and refractory multiple myeloma (MM) and has recently been approved in the frontline setting for MM patients ineligible for transplantation. In the future, expanded indications are possible for daratumumab and other anti-CD38 monoclonal antibodies in development. For several years, it has been recognized that these therapies interfere with blood bank testing by binding to CD38 on red blood cells and causing panagglutination on the Indirect Antiglobulin Test. This can lead to redundant testing and significant delays in patient care. Given the anticipated increase in utilization of anti-CD38 monoclonal antibodies, as well as the transfusion needs of MM patients, it is critical to understand the nature of this interference with blood bank testing and to optimize clinical and laboratory procedures. In this review, we summarize the pathophysiology of this phenomenon, examine the clinical data reported to date, describe currently available methods to resolve this issue, and lastly provide a guide to clinical management of blood transfusions for patients receiving anti-CD38 monoclonal antibodies

    Diagnostic yield of renal biopsies: a retrospective single center review

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    <p>Abstract</p> <p>Background</p> <p>Previous studies have examined the spectrum of diseases identified with a kidney biopsy and the complications of the procedure. However, few studies have examined the utility of the test to clarify the diagnosis and guide treatment of pediatric patients. This retrospective, single-center chart review was performed to test the hypothesis that at least 80% of native kidney biopsies provide clinically valuable information that rationally guides diagnosis and patient management.</p> <p>Methods</p> <p>200 biopsies performed between January 1, 2000 and June 30, 2008 were reviewed. A scheme composed of six categories was devised to classify the utility of each kidney biopsy.</p> <p>Results</p> <p>196 complete case files were available for review. Twenty-four (12.2%) biopsies did not shed light on the diagnosis and were unhelpful in patient management – 21 biopsies (10.7%) were non-diagnostic and 3 (1.5%) failed to yield enough tissue for examination. The number of unhelpful biopsies did not cluster in any specific disease entity.</p> <p>Conclusion</p> <p>Our findings provide guidance to nephrologists about the total risk of a kidney biopsy, including uninformative results, when seeking informed consent for the procedure. The results suggest an appropriate balance has been reached which maximizes the use of kidney biopsies while minimizing the risk of this invasive procedure (word count: 202).</p

    SARS-CoV-2 Vaccine Responses in Individuals with Antibody Deficiency: Findings from the COV-AD Study

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    BACKGROUND: Vaccination prevents severe morbidity and mortality from COVID-19 in the general population. The immunogenicity and efficacy of SARS-CoV-2 vaccines in patients with antibody deficiency is poorly understood. OBJECTIVES: COVID-19 in patients with antibody deficiency (COV-AD) is a multi-site UK study that aims to determine the immune response to SARS-CoV-2 infection and vaccination in patients with primary or secondary antibody deficiency, a population that suffers from severe and recurrent infection and does not respond well to vaccination. METHODS: Individuals on immunoglobulin replacement therapy or with an IgG less than 4 g/L receiving antibiotic prophylaxis were recruited from April 2021. Serological and cellular responses were determined using ELISA, live-virus neutralisation and interferon gamma release assays. SARS-CoV-2 infection and clearance were determined by PCR from serial nasopharyngeal swabs. RESULTS: A total of 5.6% (n = 320) of the cohort reported prior SARS-CoV-2 infection, but only 0.3% remained PCR positive on study entry. Seropositivity, following two doses of SARS-CoV-2 vaccination, was 54.8% (n = 168) compared with 100% of healthy controls (n = 205). The magnitude of the antibody response and its neutralising capacity were both significantly reduced compared to controls. Participants vaccinated with the Pfizer/BioNTech vaccine were more likely to be seropositive (65.7% vs. 48.0%, p = 0.03) and have higher antibody levels compared with the AstraZeneca vaccine (IgGAM ratio 3.73 vs. 2.39, p = 0.0003). T cell responses post vaccination was demonstrable in 46.2% of participants and were associated with better antibody responses but there was no difference between the two vaccines. Eleven vaccine-breakthrough infections have occurred to date, 10 of them in recipients of the AstraZeneca vaccine. CONCLUSION: SARS-CoV-2 vaccines demonstrate reduced immunogenicity in patients with antibody deficiency with evidence of vaccine breakthrough infection
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