1,436 research outputs found
Post-Translational Control of Retinoblastoma Protein Phosphorylation
The retinoblastoma tumor suppressor protein (pRB) functions through multiple mechanisms to serve as a tumor suppressor. pRB has been well characterized to be inactivated through phosphorylation by CDKs. pRB dephosphorylation and activation is a much less characterized aspect of pRB function. In this thesis, I detail work to study the post translational control of pRB phosphorylation. Here I present work detailing efforts to generate a gene targeted mouse which disrupts PP1 binding to the C-terminus of pRB, allowing for detailed study of the mechanisms of pRB dephosphorylation. This work also details an examination of acetylation in the C-terminus of pRB, which disrupts CDK phosphorylation of pRB. I generated a site specific antibody to examine K873/K874 acetylation, and carried out characterization of this set of post-translational modifications. This work highlights the complex mechanisms surrounding pRB phosphorylation state and regulation of pRB activation
Space Station Engineering Design Issues
Space Station Freedom topics addressed include: general design issues; issues related to utilization and operations; issues related to systems requirements and design; and management issues relevant to design
Co-occurrence of ASD and ADHD traits in an adult population
Objective: ADHD and autism spectrum disorder (ASD) can be viewed as the extreme end of traits found in the general population. Clinical and genetic studies suggest that ADHD and ASD often co-occur and share genetic susceptibility. The aim of this study was to examine co-occurrence of ADHD and ASD traits in the general population.
Method: In total, 334 participants were recruited from a population-based sample. Four questionnaires assessing current and retrospective ADHD and ASD traits were administered online: the Adult ADHD Self-Report Scale (ASRS) Symptom Checklist, the Wender Utah Rating Scale (WURS-25), the Broad Autism Phenotype Questionnaire (BAPQ), and the Autism Spectrum Quotient (AQ).
Results: A significant correlation was found between ADHD and autistic traits. In particular, higher inattention and overall ADHD scores were associated with self-reported deficits in communication and social skills.
Conclusion: Our findings are similar to results from studies on clinical populations, suggesting that ADHD and ASD might share common etiology
A retinoblastoma allele that is mutated at its common E2F interaction site inhibits cell proliferation in gene-targeted mice
The retinoblastoma protein (pRB) is best known for regulating cell proliferation through E2F transcription factors. In this report, we investigate the properties of a targeted mutation that disrupts pRB interactions with the transactivation domain of E2Fs. Mice that carry this mutation endogenously (Rb1δG) are defective for pRB-dependent repression of E2F target genes. Except for an accelerated entry into S phase in response to serum stimulation, cell cycle regulation in Rb1δG/δG mouse embryonic fibroblasts (MEFs) strongly resembles that of the wild type. In a serum deprivation-induced cell cycle exit, Rb1δG/δG MEFs display a magnitude of E2F target gene derepression similar to that of Rb1-/- cells, even though Rb1δG/δG cells exit the cell cycle normally. Interestingly, cell cycle arrest in Rb1δG/δG MEFs is responsive to p16 expression and gamma irradiation, indicating that alternate mechanisms can be activated in G1 to arrest proliferation. Some Rb1δG/δG mice die neonatally with a muscle degeneration phenotype, while the others live a normal life span with no evidence of spontaneous tumor formation. Most tissues appear histologically normal while being accompanied by derepression of pRB-regulated E2F targets. This suggests that non- E2F-, pRB-dependent pathways may have a more relevant role in proliferative control than previously identified. © 2014, American Society for Microbiology
Prototype finline-coupled TES bolometers for CLOVER
CLOVER is an experiment which aims to detect the signature of gravitational
waves from inflation by measuring the B-mode polarization of the cosmic
microwave background. CLOVER consists of three telescopes operating at 97, 150,
and 220 GHz. The 97-GHz telescope has 160 feedhorns in its focal plane while
the 150 and 220-GHz telescopes have 256 horns each. The horns are arranged in a
hexagonal array and feed a polarimeter which uses finline-coupled TES
bolometers as detectors. To detect the two polarizations the 97-GHz telescope
has 320 detectors while the 150 and 220-GHz telescopes have 512 detectors each.
To achieve the target NEPs (1.5, 2.5, and 4.5x10^-17 W/rtHz) the detectors are
cooled to 100 mK for the 97 and 150-GHz polarimeters and 230 mK for the 220-GHz
polarimeter. Each detector is fabricated as a single chip to ensure a 100%
operational focal plane. The detectors are contained in linear modules made of
copper which form split-block waveguides. The detector modules contain 16 or 20
detectors each for compatibility with the hexagonal arrays of horns in the
telescopes' focal planes. Each detector module contains a time-division SQUID
multiplexer to read out the detectors. Further amplification of the multiplexed
signals is provided by SQUID series arrays. The first prototype detectors for
CLOVER operate with a bath temperature of 230 mK and are used to validate the
detector design as well as the polarimeter technology. We describe the design
of the CLOVER detectors, detector blocks, and readout, and present preliminary
measurements of the prototype detectors performance.Comment: 4 pages, 6 figures; to appear in the Proceedings of the 17th
International Symposium on Space Terahertz Technology, held 10-12 May 2006 in
Pari
Beyond the heterodimer model for mineralocorticoid and glucocorticoid receptor interactions in nuclei and at DNA.
Glucocorticoid (GR) and mineralocorticoid receptors (MR) are believed to classically bind DNA as homodimers or MR-GR heterodimers to influence gene regulation in response to pulsatile basal or stress-evoked glucocorticoid secretion. Pulsed corticosterone presentation reveals MR and GR co-occupy DNA only at the peaks of glucocorticoid oscillations, allowing interaction. GR DNA occupancy was pulsatile, while MR DNA occupancy was prolonged through the inter-pulse interval. In mouse mammary 3617 cells MR-GR interacted in the nucleus and at a chromatin-associated DNA binding site. Interactions occurred irrespective of ligand type and receptors formed complexes of higher order than heterodimers. We also detected MR-GR interactions ex-vivo in rat hippocampus. An expanded range of MR-GR interactions predicts structural allostery allowing a variety of transcriptional outcomes and is applicable to the multiple tissue types that co-express both receptors in the same cells whether activated by the same or different hormones
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A pilot randomised controlled trial of personalised care for depressed patients with symptomatic coronary heart disease in South London general practices: the UPBEAT-UK RCT protocol and recruitment.
ABSTRACT:
Background: Community studies reveal people with coronary heart disease (CHD) are twice as likely to be depressed as the general population and that this co-morbidity negatively affects the course and outcome of both conditions. There is evidence for the efficacy of collaborative care and case management for depression treatment, and whilst NICE guidelines recommend these approaches only where depression has not responded to psychological, pharmacological, or combined treatments, these care approaches may be particularly relevant to the needs of people with CHD and depression in the earlier stages of stepped care in primary care settings.
Methods: This pilot randomised controlled trial will evaluate whether a simple intervention involving a personalised care plan, elements of case management and regular telephone review is a feasible and acceptable intervention that leads to better mental and physical health outcomes for these patients. The comparator group will be usual general practitioner (GP) care.
81 participants have been recruited from CHD registers of 15 South London general practices. Eligible participants have probable major depression identified by a score of ≥8 on the Hospital Anxiety and Depression Scale depression subscale (HADS-D) together with symptomatic CHD identified using the Modified Rose Angina Questionnaire.
Consenting participants are randomly allocated to usual care or the personalised care intervention which involves a comprehensive assessment of each participant’s physical and mental health needs which are documented in a care plan, followed by regular telephone reviews by the case manager over a 6-month period. At each review, the intervention participant’s mood, function and identified problems are reviewed and the case manager uses evidence based behaviour change techniques to facilitate achievement of goals specified by the patient with the aim of increasing the patient’s self efficacy to solve their problems.
Depressive symptoms measured by HADS score will be collected at baseline and 1, 6- and 12 months post randomisation. Other outcomes include CHD symptoms, quality of life, wellbeing and health service utilisation.
Discussion: This practical and patient-focused intervention is potentially an effective and accessible approach to the health and social care needs of people with depression and CHD in primary care.
Trial registration: ISRCTN21615909
The Turkey Ig-like receptor family: identification, expression and function.
The chicken leukocyte receptor complex located on microchromosome 31 encodes the chicken Ig-like receptors (CHIR), a vastly expanded gene family which can be further divided into three subgroups: activating CHIR-A, bifunctional CHIR-AB and inhibitory CHIR-B. Here, we investigated the presence of CHIR homologues in other bird species. The available genome databases of turkey, duck and zebra finch were screened with different strategies including BLAST searches employing various CHIR sequences, and keyword searches. We could not identify CHIR homologues in the distantly related zebra finch and duck, however, several partial and complete sequences of CHIR homologues were identified on chromosome 3 of the turkey genome. They were designated as turkey Ig-like receptors (TILR). Using cDNA derived from turkey blood and spleen RNA, six full length TILR could be amplified and further divided according to the typical sequence features into one activating TILR-A, one inhibitory TILR-B and four bifunctional TILR-AB. Since the TILR-AB sequences all displayed the critical residues shown to be involved in binding to IgY, we next confirmed the IgY binding using a soluble TILR-AB1-huIg fusion protein. This fusion protein reacted with IgY derived from various gallinaceous birds, but not with IgY from other bird species. Finally, we tested various mab directed against CHIR for their crossreactivity with either turkey or duck leukocytes. Whereas no staining was detectable with duck cells, the CHIR-AB1 specific mab 8D12 and the CHIR-A2 specific mab 13E2 both reacted with a leukocyte subpopulation that was further identified as thrombocytes by double immunofluorescence employing B-cell, T-cell and thrombocyte specific reagents. In summary, although the turkey harbors similar LRC genes as the chicken, their distribution seems to be distinct with predominance on thrombocytes rather than lymphocytes
Utility of Social Modeling in Assessment of a State’s Propensity for Nuclear Proliferation
This report is the third and final report out of a set of three reports documenting research for the U.S. Department of Energy (DOE) National Security Administration (NASA) Office of Nonproliferation Research and Development NA-22 Simulations, Algorithms, and Modeling program that investigates how social modeling can be used to improve proliferation assessment for informing nuclear security, policy, safeguards, design of nuclear systems and research decisions. Social modeling has not to have been used to any significant extent in a proliferation studies. This report focuses on the utility of social modeling as applied to the assessment of a State's propensity to develop a nuclear weapons program
Meta-analysis of genome-wide association studies of HDL cholesterol response to statins
In addition to lowering low density lipoprotein-cholesterol (LDL-C), statin therapy also raises high density lipoprotein-cholesterol (HDL-C) levels. Inter-individual variation in HDL-C response to statins may be partially explained by genetic variation
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