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Find video protocols related to scientific articles indexed in Pubmed.
Percutaneous Clinical T1a Renal Mass Ablation in the Octogenarian and Nonagenarian: Oncologic Outcomes and Morbidity.
J. Endourol.
PUBLISHED: 11-12-2014
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Objective: To evaluate outcomes of percutaneous ablation of small renal tumors in the elderly population. Patients and Methods: Utilizing our tumor ablation database, we searched for percutaneous ablation procedures for clinical T1a renal masses in octogenarians and nonagenarians between June 2001 and May 2012. Altogether 105 tumors from 99 procedures among 95 patients (mean age 84.0 ± 3.0 years, range 80-92) were identified. Oncologic outcomes and major complications were evaluated. Assessment also included patient hospital stays and renal functional outcomes. Results: Technical success was achieved in 60/61 (98.4%) tumors treated with cryoablation and 43/44 (97.7%) after radiofrequency ablation (RFA). Of 87 renal tumors with at least 3 months imaging follow up, 2 (5.4%) tumors progressed at 1.2 and 2.2 years following RFA. None recurred following cryoablation. Estimated progression-free survival rates at 1, 3, and 5 years following ablation were 99%, 97%, and 97%, respectively. Thirty-four patients died at a mean of 3.7 years following ablation (median 3.7; range 0.4-9.6). Estimated overall survival rates were 98%, 83%, and 61%, respectively. Among 33 patients with sporadic, biopsy-proven renal cell carcinoma, estimated cancer-specific survival rates were 100%, 100%, and 86%, respectively. Five (8.6%) major complications developed after renal cryoablation with no (0%) major complication after RFA. Mean decrease in serum creatinine within one week following ablation was 0.1 mg/dL. Mean hospitalization was 1.2 days. Conclusion: Percutaneous thermal ablation is safe and effective in the active management of clinical T1a renal masses in elderly patients. These results should help urologists appropriately assess expected outcomes when counseling octogenarian and nonagenarian patients.
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Development of a Measure of College Students' Adherence to Religious Doctrine Concerning Sexual Behavior.
J Am Coll Health
PUBLISHED: 10-23-2014
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Abstract Objective: The authors developed a 14-item measure of adherence to religious doctrine concerning sexual behaviors (ARDSB). The ARDSB psychometric properties were investigated to better understand religious motivations associated with changes in sexual behavior that may provide support for sexual health promotion and prevention programs. Participants: Four hundred eighty-three undergraduates ages 18-26. Methods: Data was collected from an online survey during the 2012-2013 academic school year. Results: Principle components factor analysis identified two factors: reasons to break religious doctrine and reasons to adhere to religious doctrine concerning sexual behavior. The subscales had good internal consistency. Correlations, t-tests, and analyses of variance of the subscales with measures of intrinsic and extrinsic religiosity and self-reported sexual behavior and risk provide support for concurrent validity. Conclusions: The ARDSB could be employed as a measure to better understand sexual behavior; it is inexpensive and relatively easy to employ in both research and campus ministry settings.
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Transcriptional Regulatory Events Initiated by Ascl1 and Neurog2 During Neuronal Differentiation of P19 Embryonic Carcinoma Cells.
J. Mol. Neurosci.
PUBLISHED: 09-06-2014
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As members of the proneural basic-helix-loop-helix (bHLH) family of transcription factors, Ascl1 and Neurog2 direct the differentiation of specific populations of neurons at various times and locations within the developing nervous system. In order to characterize the mechanisms employed by these two bHLH factors, we generated stable, doxycycline-inducible lines of P19 embryonic carcinoma cells that express comparable levels of Ascl1 and Neurog2. Upon induction, both Ascl1 and Neurog2 directed morphological and immunocytochemical changes consistent with initiation of neuronal differentiation. Comparison of Ascl1- and Neurog2-regulated genes by microarray analyses showed both shared and distinct transcriptional changes for each bHLH protein. In both Ascl1- and Neurog2-differentiating cells, repression of Oct4 mRNA levels was accompanied by increased Oct4 promoter methylation. However, DNA demethylation was not detected for genes induced by either bHLH protein. Neurog2-induced genes included glutamatergic marker genes while Ascl1-induced genes included GABAergic marker genes. The Neurog2-specific induction of a gene encoding a protein phosphatase inhibitor, Ppp1r14a, was dependent on distinct, canonical E-box sequences within the Ppp1r14a promoter and the nucleotide sequences within these E-boxes were partially responsible for Neurog2-specific regulation. Our results illustrate multiple novel mechanisms by which Ascl1 and Neurog2 regulate gene repression during neuronal differentiation in P19 cells.
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Lung transplantation in adults and children: Putting lung function into perspective.
Respirology
PUBLISHED: 09-03-2014
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The number of lung transplants performed globally continues to increase year after year. Despite this growing experience, long-term outcomes following lung transplantation continue to fall far short of that described in other solid-organ transplant settings. Chronic lung allograft dysfunction (CLAD) remains common and is the end result of exposure to a multitude of potentially injurious insults that include alloreactivity and infection among others. Central to any description of the clinical performance of the transplanted lung is an assessment of its physiology by pulmonary function testing. Spirometry and the evaluation of forced expiratory volume in 1?s and forced vital capacity, remain core indices that are measured as part of routine clinical follow-up. Spirometry, while reproducible in detecting lung allograft dysfunction, lacks specificity in differentiating the different complications of lung transplantation such as rejection, infection and bronchiolitis obliterans. However, interpretation of spirometry is central to defining the different 'chronic rejection' phenotypes. It is becoming apparent that the maximal lung function achieved following transplantation, as measured by spirometry, is influenced by a number of donor and recipient factors as well as the type of surgery performed (single vs double vs lobar lung transplant). In this review, we discuss the wide range of variables that need to be considered when interpreting lung function testing in lung transplant recipients. Finally, we review a number of novel measurements of pulmonary function that may in the future serve as better biomarkers to detect and diagnose the cause of the failing lung allograft.
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Incomplete deletion of IL-4R? by LysM(Cre) reveals distinct subsets of M2 macrophages controlling inflammation and fibrosis in chronic schistosomiasis.
PLoS Pathog.
PUBLISHED: 09-01-2014
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Mice expressing a Cre recombinase from the lysozyme M-encoding locus (Lyz2) have been widely used to dissect gene function in macrophages and neutrophils. Here, we show that while naïve resident tissue macrophages from IL-4R?f(lox/delta)LysM(Cre) mice almost completely lose IL-4R? function, a large fraction of macrophages elicited by sterile inflammatory stimuli, Schistosoma mansoni eggs, or S. mansoni infection, fail to excise Il4r?. These F4/80(hi)CD11b(hi) macrophages, in contrast to resident tissue macrophages, express lower levels of Lyz2 explaining why this population resists LysM(Cre)-mediated deletion. We show that in response to IL-4 and IL-13, Lyz2(lo)IL-4R?(+) macrophages differentiate into an arginase 1-expressing alternatively-activated macrophage (AAM) population, which slows the development of lethal fibrosis in schistosomiasis. In contrast, we identified Lyz2(hi)IL-4R?(+) macrophages as the key subset of AAMs mediating the downmodulation of granulomatous inflammation in chronic schistosomiasis. Our observations reveal a limitation on using a LysMCre mouse model to study gene function in inflammatory settings, but we utilize this limitation as a means to demonstrate that distinct populations of alternatively activated macrophages control inflammation and fibrosis in chronic schistosomiasis.
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Evaluation of high-fidelity simulation training in radiation oncology using an outcomes logic model.
Radiat Oncol
PUBLISHED: 08-28-2014
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To evaluate the feasibility and educational value of high-fidelity, interprofessional team-based simulation in radiation oncology.
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Syringomyelia and vertebral osteochondromas in patients with multiple hereditary exostosis.
J Pediatr Orthop B
PUBLISHED: 07-01-2014
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Involvement of osteochondromas in the spinal canal occurs in patients with multiple hereditary exostosis, but the exact prevalence is unknown. A recent study found an incidence of 68%, with 27% of these lesions encroaching into the spinal canal. We studied MRI findings of 27 patients with multiple hereditary exostosis and found only six (23.1%) patients with osteochondromas arising from the spinal column and three (11.5%) patients with encroachment into the spinal canal. We also found three (11.5%) patients with an incidental syringomyelia. Only five of the nine (55.6%) patients with positive findings on MRI had symptoms prompting the MRI and two patients had significant symptoms that required surgical excision. Although the incidence of spinal osteochondroma in our population is lower than that of previous studies, we found a relatively high incidence of syringomyelia in these patients, which has not been previously reported.
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Contribution of the acetate anion to CO2 solubility in ionic liquids: theoretical method development and experimental study.
J Phys Chem B
PUBLISHED: 06-24-2014
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A new theoretical method was developed to compute the Henry's law constant for gas absorption in a solvent through strong nonphysical interactions. The new method was created by expanding the test particle insertion method typically applied to physisorbing systems to account for the strong intermolecular interactions present in chemisorbing systems. By using an ab initio (AI)-based Boltzmann-averaged potential to model the interaction between CO2 and the tetra-n-butylphosphonium acetate ([P4444][CH3COO]) ionic liquid, the total Henrys's law constant at 298 K was computed to be 0.011 to 0.039 bar, reasonably comparable to the experimental value of 0.18 bar measured in this work. Three different AI potentials were used to verify the applicability of this approach. In contrast, when a classical force field (FF) was used to describe the interaction between CO2 and [P4444][CH3COO], the Henry's law constant was computed to be 27 bar, significantly larger than the experimental value. The classical FF underestimates the CO2-[P4444][CH3COO] interaction compared with the AI calculations, which in turn leads to the smaller simulated CO2 solubility. Simulations further indicate that the CO2 interaction with the [CH3COO](-) anion is much stronger than with the [P4444](+) cation. This result strongly suggests that the large CO2 solubility in [P4444][CH3COO] is due to the strong CO2-[CH3COO](-) interaction.
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Role of transcription factor CCAAT/enhancer-binding protein alpha in human fetal liver cell types in vitro.
Hepatol. Res.
PUBLISHED: 06-10-2014
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The transcription factor CCAAT/enhancer-binding protein alpha (C/EBP?) has been shown to play an important role in liver development, cell proliferation and differentiation. It is, however, largely unknown if C/EBP? regulates cell differentiation and proliferation differently in the diverse cell types of the human liver. We investigated the role of C/EBP? in primary human fetal liver cells and liver cell subpopulations in vitro using a 3-D perfusion bioreactor as an advanced in vivo-like human organ culture model.
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Trifluoroethanethiol: an additive for efficient one-pot peptide ligation-desulfurization chemistry.
J. Am. Chem. Soc.
PUBLISHED: 05-29-2014
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Native chemical ligation followed by desulfurization is a powerful strategy for the assembly of proteins. Here we describe the development of a high-yielding, one-pot ligation-desulfurization protocol that uses trifluoroethanethiol (TFET) as a novel thiol additive. The synthetic utility of this TFET-enabled methodology is demonstrated by the efficient multi-step one-pot syntheses of two tick-derived proteins, chimadanin and madanin-1, without the need for any intermediary purification.
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Stereotactic body radiotherapy in patients with previous pneumonectomy: safety and efficacy.
J Thorac Oncol
PUBLISHED: 05-16-2014
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There are limited treatment options for patients with prior pneumonectomy and a new lung malignancy. The safety and efficacy of stereotactic body radiotherapy in this subpopulation has not been well defined.
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Signature limits in mindreading systems.
Cogn Sci
PUBLISHED: 03-20-2014
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Recent evidence that young children seem to both understand false belief in one sense, but not in another, has led to two-systems theorizing about mindreading. By analyzing the most detailed two-systems approach in studying social cognition-the theory of mindreading defended by Ian Apperly and Stephen Butterfill-I argue that that even when dutifully constructed, two-systems approaches in social cognition struggle to adequately define the mindreading systems in terms of signature processing limits, an issue that becomes most apparent when investigating mindreading in infancy. I end the article by developing several challenges that face any two-systems account of mindreading.
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Preoperative neutrophil-lymphocyte ratio predicts death among patients with localized clear cell renal carcinoma undergoing nephrectomy.
Urol. Oncol.
PUBLISHED: 03-12-2014
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The neutrophil-lymphocyte ratio (NLR) is an indicator of the systemic inflammatory response. An increased pretreatment NLR has been associated with adverse outcomes in other malignancies, but its role in localized (M0) clear cell renal cell carcinoma (ccRCC) remains unclear. As such, we evaluated the ability of preoperative NLR to predict oncologic outcomes in patients with M0 ccRCC undergoing radical nephrectomy (RN).
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Basal microRNA expression patterns in reward circuitry of selectively bred high-responder and low-responder rats vary by brain region and genotype.
Physiol. Genomics
PUBLISHED: 02-25-2014
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Mental health disorders involving altered reward, emotionality, and anxiety are thought to result from the interaction of individual predisposition (genetic factors) and personal experience (environmental factors), although the mechanisms that contribute to an individual's vulnerability to these disorders remain poorly understood. We used an animal model of individual variation [inbred high-responder/low-responder (bHR-bLR) rodents] known to vary in reward, anxiety, and emotional processing to examine neuroanatomical expression patterns of microRNAs (miRNAs). Laser capture microdissection was used to dissect the prelimbic cortex and the nucleus accumbens core and shell prior to analysis of basal miRNA expression in bHR and bLR male rats. These studies identified 187 miRNAs differentially expressed by genotype in at least one brain region, 10 of which were validated by qPCR. Four of these 10 qPCR-validated miRNAs demonstrated differential expression across multiple brain regions, and all miRNAs with validated differential expression between genotypes had lower expression in bHR animals compared with bLR animals. microRNA (miR)-484 and miR-128a expression differences between the prelimbic cortex of bHR and bLR animals were validated by semiquantitative in situ hybridization. miRNA expression analysis independent of genotype identified 101 miRNAs differentially expressed by brain region, seven of which validated by qPCR. Dnmt3a mRNA, a validated target of miR-29b, varied in a direction opposite that of miR-29b's differential expression between bHR and bLR animals. These data provide evidence that basal central nervous system miRNA expression varies in the bHR-bLR model, implicating microRNAs as potential epigenetic regulators of key neural circuits and individual differences associated with mental health disorders.
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Synthesis of full length and truncated microcin B17 analogues as DNA gyrase poisons.
Org. Biomol. Chem.
PUBLISHED: 01-23-2014
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Microcin B17 (MccB17) is a post-translationally modified peptide containing thiazole and oxazole heterocycles that interrupt the peptide backbone. MccB17 is capable of poisoning DNA gyrase through stabilization of the gyrase-DNA cleavage complex and has therefore attracted significant attention. Using a combination of Fmoc-strategy solid-phase peptide synthesis and solution-phase fragment assembly we have prepared a library of full-length and truncated MccB17 analogues to investigate key structural requirements for gyrase-poisoning activity. Synthetic peptides lacking the glycine-rich N-terminal portion of the full-length sequence showed strong stabilization of the gyrase-DNA cleavage complex with increased potency relative to the full-length sequences. This truncation, however, led to a decrease in antibacterial activity of these analogues relative to their full-length counterparts indicating a potential role of the N-terminal region of the natural product for cellular uptake.
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Psychological and educational interventions for atopic eczema in children.
Cochrane Database Syst Rev
PUBLISHED: 01-09-2014
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Psychological and educational interventions have been used as an adjunct to conventional therapy for children with atopic eczema to enhance the effectiveness of topical therapy. This is an update of the original Cochrane review.
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Repeated exposure to conditioned fear stress increases anxiety and delays sleep recovery following exposure to an acute traumatic stressor.
Front Psychiatry
PUBLISHED: 01-01-2014
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Repeated stressor exposure can sensitize physiological responses to novel stressors and facilitate the development of stress-related psychiatric disorders including anxiety. Disruptions in diurnal rhythms of sleep-wake behavior accompany stress-related psychiatric disorders and could contribute to their development. Complex stressors that include fear-eliciting stimuli can be a component of repeated stress experienced by human beings, but whether exposure to repeated fear can prime the development of anxiety and sleep disturbances is unknown. In the current study, adult male F344 rats were exposed to either control conditions or repeated contextual fear conditioning for 22?days followed by exposure to no, mild (10), or severe (100) acute uncontrollable tail shock stress. Exposure to acute stress produced anxiety-like behavior as measured by a reduction in juvenile social exploration and exaggerated shock-elicited freezing in a novel context. Prior exposure to repeated fear enhanced anxiety-like behavior as measured by shock-elicited freezing, but did not alter social exploratory behavior. The potentiation of anxiety produced by prior repeated fear was temporary; exaggerated fear was present 1?day but not 4?days following acute stress. Interestingly, exposure to acute stress reduced rapid eye movement (REM) and non-REM (NREM) sleep during the hours immediately following acute stress. This initial reduction in sleep was followed by robust REM rebound and diurnal rhythm flattening of sleep/wake behavior. Prior repeated fear extended the acute stress-induced REM and NREM sleep loss, impaired REM rebound, and prolonged the flattening of the diurnal rhythm of NREM sleep following acute stressor exposure. These data suggest that impaired recovery of sleep/wake behavior following acute stress could contribute to the mechanisms by which a history of prior repeated stress increases vulnerability to subsequent novel stressors and stress-related disorders.
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Altered choroid plexus gene expression in major depressive disorder.
Front Hum Neurosci
PUBLISHED: 01-01-2014
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Given the emergent interest in biomarkers for mood disorders, we assessed gene expression in the choroid plexus (CP), the region that produces cerebrospinal fluid (CSF), in individuals with major depressive disorder (MDD). Genes that are expressed in the CP can be secreted into the CSF and may be potential biomarker candidates. Given that we have previously shown that fibroblast growth factor family members are differentially expressed in post-mortem brain of subjects with MDD and the CP is a known source of growth factors in the brain, we posed the question whether growth factor dysregulation would be found in the CP of subjects with MDD. We performed laser capture microscopy of the CP at the level of the hippocampus in subjects with MDD and psychiatrically normal controls. We then extracted, amplified, labeled, and hybridized the cRNA to Illumina BeadChips to assess gene expression. In controls, the most highly abundant known transcript was transthyretin. Moreover, half of the 14 most highly expressed transcripts in controls encode ribosomal proteins. Using BeadStudio software, we identified 169 transcripts differentially expressed (p < 0.05) between control and MDD samples. Using pathway analysis we noted that the top network altered in subjects with MDD included multiple members of the transforming growth factor-beta (TGF?) pathway. Quantitative real-time PCR (qRT-PCR) confirmed downregulation of several transcripts that interact with the extracellular matrix in subjects with MDD. These results suggest that there may be an altered cytoskeleton in the CP in MDD subjects that may lead to a disrupted blood-CSF-brain barrier.
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One-Pot Peptide Ligation-Desulfurization at Glutamate.
Org. Lett.
PUBLISHED: 12-02-2013
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An efficient methodology for ligation at glutamate (Glu) is described. A ?-thiol-Glu building block was accessed in only three steps from protected glutamic acid and could be incorporated at the N-terminus of peptides. The application of these peptides in one-pot ligation-desulfurization chemistry is demonstrated with a range of peptide thioesters, and the utility of this methodology is highlighted through the synthesis of the osteoporosis peptide drug teriparatide (Forteo).
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Fibrinogen-specific antibody induces abdominal aortic aneurysm in mice through complement lectin pathway activation.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 10-28-2013
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Abdominal aortic aneurysm (AAA) is a common vascular disease associated with high mortality rate due to progressive enlargement and eventual rupture. There is currently no established therapy known to alter the rate of aneurysmal expansion. Thus, understanding the processes that initiate and sustain aneurysmal growth is pivotal for the development of medical therapies aimed at halting disease progression. Using an elastase-induced AAA mouse model that recapitulates key features of human AAA, we previously reported that a natural IgG antibody directs alternative pathway complement activation and initiates the inflammatory process that culminates in aneurysmal development. The target of this natural antibody, however, was unknown. Herein we identify a natural IgG that binds to fibrinogen deposited in elastase-perfused aortic tissues, activates the complement lectin pathway (LP), and induces AAA. Moreover, we establish that alterations in the glycosylation patterns of this antibody critically affect its ability to activate the LP in vivo. We find that LP activation precedes the alternative pathway and absence of the LP complement protein mannan-binding lectin abrogates elastase-induced AAA. In human AAA tissues the mouse anti-fibrinogen antibody recognizes epitopes that localize to the same areas that stain positively for mannan-binding lectin, which suggests that the complement LP is engaged in humans as well. Lastly, we demonstrate that circulating antibodies in a subset of AAA patients react against fibrinogen or fibrinogen-associated epitopes in human aneurysmal tissues. Our findings support the concept that an autoimmune process directed at aortic wall self-antigens may play a central role in the immunopathogenesis of AAA.
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Successful treatment of tumor-induced osteomalacia due to an intracranial tumor by fractionated stereotactic radiotherapy.
J. Clin. Endocrinol. Metab.
PUBLISHED: 09-06-2013
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Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome, characterized by tumor secretion of fibroblast growth factor-23 (FGF23) causing hypophosphatemia due to renal phosphate wasting. TIO is usually caused by small, benign, difficult-to-localize, mesenchymal tumors. Although surgery with wide excision of tumor borders is considered the "gold standard" for definitive therapy, it can be associated with considerable morbidity depending on the location. To date, radiation therapy has not been considered as an effective treatment modality in TIO.
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Enhancing neural transmission in multiple sclerosis (4-aminopyridine therapy).
Neurotherapeutics
PUBLISHED: 07-31-2013
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Enhancing neural transmission by improving axonal conduction and synaptic neurotransmitter release is a novel strategy to improve symptoms in multiple sclerosis. Dalfampridine (4-aminopyridine extended-release) is a first-in-class medication that targets the damaged nervous system through blockage of voltage-gated potassium channels. Through a series of clinical trials, dalfampridine (dosed at 10 mg twice daily) has been found to improve walking speed by approximately 25 % on average in one third of individuals with multiple sclerosis regardless of disease stage. Furthermore, it significantly improves patients perception of their ambulatory disability and may improve lower extremity strength. Given the mechanism of action, the most serious adverse effect is its pro-convulsant property, which occurs more frequently at high serum concentrations. The most common adverse events include increased falls, urinary tract infections, dizziness, insomnia, and headaches. Despite these potential side-effects, the vast majority of individuals who derive benefit continue on the treatment. The exact mechanism of action is uncertain, as is the reason for response variability. The medication serves as proof-of-concept that targeting axonal transmission can improve disability in multiple sclerosis.
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Smooth muscle cells from abdominal aortic aneurysms are unique and can independently and synergistically degrade insoluble elastin.
J. Vasc. Surg.
PUBLISHED: 04-30-2013
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The purpose of this study was to further elucidate the role of the vascular smooth muscle cells (SMCs) in abdominal aortic aneurysm (AAA) disease. We hypothesized that that AAA SMCs are unique and actively participate in the process of degrading the aortic matrix.
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CD14 directs adventitial macrophage precursor recruitment: role in early abdominal aortic aneurysm formation.
J Am Heart Assoc
PUBLISHED: 03-30-2013
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Recruitment of macrophage precursors to the adventitia plays a key role in the pathogenesis of abdominal aortic aneurysms (AAAs), but molecular mechanisms remain undefined. The innate immune signaling molecule CD14 was reported to be upregulated in adventitial macrophages in a murine model of AAA and in monocytes cocultured with aortic adventitial fibroblasts (AoAf) in vitro, concurrent with increased interleukin-6 (IL-6) expression. We hypothesized that CD14 plays a crucial role in adventitial macrophage precursor recruitment early during AAA formation.
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Automatic identification of bullet signatures based on consecutive matching striae (CMS) criteria.
Forensic Sci. Int.
PUBLISHED: 03-26-2013
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The consecutive matching striae (CMS) numeric criteria for firearm and toolmark identifications have been widely accepted by forensic examiners, although there have been questions concerning its observer subjectivity and limited statistical support. In this paper, based on signal processing and extraction, a model for the automatic and objective counting of CMS is proposed. The position and shape information of the striae on the bullet land is represented by a feature profile, which is used for determining the CMS number automatically. Rapid counting of CMS number provides a basis for ballistics correlations with large databases and further statistical and probability analysis. Experimental results in this report using bullets fired from ten consecutively manufactured barrels support this developed model.
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Revealing surface oxidation on the organic semi-conducting single crystal rubrene with time of flight secondary ion mass spectroscopy.
Phys Chem Chem Phys
PUBLISHED: 03-05-2013
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To address the question of surface oxidation in organic electronics the chemical composition at the surface of single crystalline rubrene is spatially profiled and analyzed using Time of Flight - Secondary Ion Mass Spectroscopy (ToF-SIMS). It is seen that a uniform oxide (C42H28O) covers the surface while there is an increased concentration of peroxide (C42H28O2) located at crystallographic defects. By analyzing the effects of different primary ions, temperature and sputtering agents the technique of ToF-SIMS is developed as a valuable tool for the study of chemical composition variance both at and below the surface of organic single crystals. The primary ion beams C60(3+) and Bi3(+) are found to be most appropriate for mass spectroscopy and spatial profiling respectively. Depth profiling of the material is successfully undertaken maintaining the molecular integrity to a depth of ~5 ?m using an Ar cluster ion source as the sputtering agent.
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Dravet syndrome patient-derived neurons suggest a novel epilepsy mechanism.
Ann. Neurol.
PUBLISHED: 02-25-2013
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Neuronal channelopathies cause brain disorders, including epilepsy, migraine, and ataxia. Despite the development of mouse models, pathophysiological mechanisms for these disorders remain uncertain. One particularly devastating channelopathy is Dravet syndrome (DS), a severe childhood epilepsy typically caused by de novo dominant mutations in the SCN1A gene encoding the voltage-gated sodium channel Na(v) 1.1. Heterologous expression of mutant channels suggests loss of function, raising the quandary of how loss of sodium channels underlying action potentials produces hyperexcitability. Mouse model studies suggest that decreased Na(v) 1.1 function in interneurons causes disinhibition. We aim to determine how mutant SCN1A affects human neurons using the induced pluripotent stem cell (iPSC) method to generate patient-specific neurons.
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Genetic relationship between five psychiatric disorders estimated from genome-wide SNPs.
, S Hong Lee, Stephan Ripke, Benjamin M Neale, Stephen V Faraone, Shaun M Purcell, Roy H Perlis, Bryan J Mowry, Anita Thapar, Michael E Goddard, John S Witte, Devin Absher, Ingrid Agartz, Huda Akil, Farooq Amin, Ole A Andreassen, Adebayo Anjorin, Richard Anney, Verneri Anttila, Dan E Arking, Philip Asherson, Maria H Azevedo, Lena Backlund, Judith A Badner, Anthony J Bailey, Tobias Banaschewski, Jack D Barchas, Michael R Barnes, Thomas B Barrett, Nicholas Bass, Agatino Battaglia, Michael Bauer, Mònica Bayés, Frank Bellivier, Sarah E Bergen, Wade Berrettini, Catalina Betancur, Thomas Bettecken, Joseph Biederman, Elisabeth B Binder, Donald W Black, Douglas H R Blackwood, Cinnamon S Bloss, Michael Boehnke, Dorret I Boomsma, Gerome Breen, René Breuer, Richard Bruggeman, Paul Cormican, Nancy G Buccola, Jan K Buitelaar, William E Bunney, Joseph D Buxbaum, William F Byerley, Enda M Byrne, Sian Caesar, Wiepke Cahn, Rita M Cantor, Miguel Casas, Aravinda Chakravarti, Kimberly Chambert, Khalid Choudhury, Sven Cichon, C Robert Cloninger, David A Collier, Edwin H Cook, Hilary Coon, Bru Cormand, Aiden Corvin, William H Coryell, David W Craig, Ian W Craig, Jennifer Crosbie, Michael L Cuccaro, David Curtis, Darina Czamara, Susmita Datta, Geraldine Dawson, Richard Day, Eco J De Geus, Franziska Degenhardt, Srdjan Djurovic, Gary J Donohoe, Alysa E Doyle, Jubao Duan, Frank Dudbridge, Eftichia Duketis, Richard P Ebstein, Howard J Edenberg, Josephine Elia, Sean Ennis, Bruno Etain, Ayman Fanous, Anne E Farmer, I Nicol Ferrier, Matthew Flickinger, Eric Fombonne, Tatiana Foroud, Josef Frank, Barbara Franke, Christine Fraser, Robert Freedman, Nelson B Freimer, Christine M Freitag, Marion Friedl, Louise Frisén, Louise Gallagher, Pablo V Gejman, Lyudmila Georgieva, Elliot S Gershon, Daniel H Geschwind, Ina Giegling, Michael Gill, Scott D Gordon, Katherine Gordon-Smith, Elaine K Green, Tiffany A Greenwood, Dorothy E Grice, Magdalena Gross, Detelina Grozeva, Weihua Guan, Hugh Gurling, Lieuwe de Haan, Jonathan L Haines, Hakon Hakonarson, Joachim Hallmayer, Steven P Hamilton, Marian L Hamshere, Thomas F Hansen, Annette M Hartmann, Martin Hautzinger, Andrew C Heath, Anjali K Henders, Stefan Herms, Ian B Hickie, Maria Hipolito, Susanne Hoefels, Peter A Holmans, Florian Holsboer, Witte J Hoogendijk, Jouke-Jan Hottenga, Christina M Hultman, Vanessa Hus, Andrés Ingason, Marcus Ising, Stéphane Jamain, Edward G Jones, Ian Jones, Lisa Jones, Jung-Ying Tzeng, Anna K Kähler, René S Kahn, Radhika Kandaswamy, Matthew C Keller, James L Kennedy, Elaine Kenny, Lindsey Kent, Yunjung Kim, George K Kirov, Sabine M Klauck, Lambertus Klei, James A Knowles, Martin A Kohli, Daniel L Koller, Bettina Konte, Ania Korszun, Lydia Krabbendam, Robert Krasucki, Jonna Kuntsi, Phoenix Kwan, Mikael Landén, Niklas Långström, Mark Lathrop, Jacob Lawrence, William B Lawson, Marion Leboyer, David H Ledbetter, Phil H Lee, Todd Lencz, Klaus-Peter Lesch, Douglas F Levinson, Cathryn M Lewis, Jun Li, Paul Lichtenstein, Jeffrey A Lieberman, Dan-Yu Lin, Don H Linszen, Chunyu Liu, Falk W Lohoff, Sandra K Loo, Catherine Lord, Jennifer K Lowe, Susanne Lucae, Donald J MacIntyre, Pamela A F Madden, Elena Maestrini, Patrik K E Magnusson, Pamela B Mahon, Wolfgang Maier, Anil K Malhotra, Shrikant M Mane, Christa L Martin, Nicholas G Martin, Manuel Mattheisen, Keith Matthews, Morten Mattingsdal, Steven A McCarroll, Kevin A McGhee, James J McGough, Patrick J McGrath, Peter McGuffin, Melvin G McInnis, Andrew McIntosh, Rebecca McKinney, Alan W McLean, Francis J McMahon, William M McMahon, Andrew McQuillin, Helena Medeiros, Sarah E Medland, Sandra Meier, Ingrid Melle, Fan Meng, Jobst Meyer, Christel M Middeldorp, Lefkos Middleton, Vihra Milanova, Ana Miranda, Anthony P Monaco, Grant W Montgomery, Jennifer L Moran, Daniel Moreno-De-Luca, Gunnar Morken, Derek W Morris, Eric M Morrow, Valentina Moskvina, Pierandrea Muglia, Thomas W Mühleisen, Walter J Muir, Bertram Müller-Myhsok, Michael Murtha, Richard M Myers, Inez Myin-Germeys, Michael C Neale, Stan F Nelson, Caroline M Nievergelt, Ivan Nikolov, Vishwajit Nimgaonkar, Willem A Nolen, Markus M Nöthen, John I Nurnberger, Evaristus A Nwulia, Dale R Nyholt, Colm O'Dushlaine, Robert D Oades, Ann Olincy, Guiomar Oliveira, Line Olsen, Roel A Ophoff, Urban Osby, Michael J Owen, Aarno Palotie, Jeremy R Parr, Andrew D Paterson, Carlos N Pato, Michele T Pato, Brenda W Penninx, Michele L Pergadia, Margaret A Pericak-Vance, Benjamin S Pickard, Jonathan Pimm, Joseph Piven, Danielle Posthuma, James B Potash, Fritz Poustka, Peter Propping, Vinay Puri, Digby J Quested, Emma M Quinn, Josep Antoni Ramos-Quiroga, Henrik B Rasmussen, Soumya Raychaudhuri, Karola Rehnström, Andreas Reif, Marta Ribasés, John P Rice, Marcella Rietschel, Kathryn Roeder, Herbert Roeyers, Lizzy Rossin, Aribert Rothenberger, Guy Rouleau, Douglas Ruderfer, Dan Rujescu, Alan R Sanders, Stephan J Sanders, Susan L Santangelo, Joseph A Sergeant, Russell Schachar, Martin Schalling, Alan F Schatzberg, William A Scheftner, Gerard D Schellenberg, Stephen W Scherer, Nicholas J Schork, Thomas G Schulze, Johannes Schumacher, Markus Schwarz, Edward Scolnick, Laura J Scott, Jianxin Shi, Paul D Shilling, Stanley I Shyn, Jeremy M Silverman, Susan L Slager, Susan L Smalley, Johannes H Smit, Erin N Smith, Edmund J S Sonuga-Barke, David St Clair, Matthew State, Michael Steffens, Hans-Christoph Steinhausen, John S Strauss, Jana Strohmaier, T Scott Stroup, James S Sutcliffe, Peter Szatmari, Szabocls Szelinger, Srinivasa Thirumalai, Robert C Thompson, Alexandre A Todorov, Federica Tozzi, Jens Treutlein, Manfred Uhr, Edwin J C G van den Oord, Gerard van Grootheest, Jim van Os, Astrid M Vicente, Veronica J Vieland, John B Vincent, Peter M Visscher, Christopher A Walsh, Thomas H Wassink, Stanley J Watson, Myrna M Weissman, Thomas Werge, Thomas F Wienker, Ellen M Wijsman, Gonneke Willemsen, Nigel Williams, A Jeremy Willsey, Stephanie H Witt, Wei Xu, Allan H Young, Timothy W Yu, Stanley Zammit, Peter P Zandi, Peng Zhang, Frans G Zitman, Sebastian Zöllner, Bernie Devlin, John R Kelsoe, Pamela Sklar, Mark J Daly, Michael C O'Donovan, Nicholas Craddock, Patrick F Sullivan, Jordan W Smoller, Kenneth S Kendler, Naomi R Wray.
Nat. Genet.
PUBLISHED: 02-10-2013
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Most psychiatric disorders are moderately to highly heritable. The degree to which genetic variation is unique to individual disorders or shared across disorders is unclear. To examine shared genetic etiology, we use genome-wide genotype data from the Psychiatric Genomics Consortium (PGC) for cases and controls in schizophrenia, bipolar disorder, major depressive disorder, autism spectrum disorders (ASD) and attention-deficit/hyperactivity disorder (ADHD). We apply univariate and bivariate methods for the estimation of genetic variation within and covariation between disorders. SNPs explained 17-29% of the variance in liability. The genetic correlation calculated using common SNPs was high between schizophrenia and bipolar disorder (0.68 ± 0.04 s.e.), moderate between schizophrenia and major depressive disorder (0.43 ± 0.06 s.e.), bipolar disorder and major depressive disorder (0.47 ± 0.06 s.e.), and ADHD and major depressive disorder (0.32 ± 0.07 s.e.), low between schizophrenia and ASD (0.16 ± 0.06 s.e.) and non-significant for other pairs of disorders as well as between psychiatric disorders and the negative control of Crohns disease. This empirical evidence of shared genetic etiology for psychiatric disorders can inform nosology and encourages the investigation of common pathophysiologies for related disorders.
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Glutamate transporters: a key piece in the glutamate puzzle of major depressive disorder.
J Psychiatr Res
PUBLISHED: 02-05-2013
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Glutamatergic therapies are emerging as the new path for the treatment of Major Depression Disorder. Recent reports reviewing the use of glutamate activity modulators in the treatment of resistant depression advocate the importance of understanding the alterations of the diverse components of this complex system in mood disorders. In this postmortem study we used in situ hybridization and microarray analysis to evaluate the gene expression of the membrane transporters SLC1A2 and SLCA3 and the vesicular transporter SLCA17A7 in the hippocampus of Major Depressive Disorder (MDD) and Bipolar Disorder (BPD) subjects. Samples from 8 controls, 11 MDD and 6 BPD subjects were processed for in situ hybridization using cRNA probes for SLC1A2, SLC1A3 and SLC17A7. Laser capture microdissection was used to collect tissue from adjacent sections for microarray analysis. The results showed that the expression of the membrane transporters SLC1A2 and SLC1A3 was diminished in the MDD group compared to controls. The expression of the vesicular glutamate transporter SLC17A7 on the other hand was increased in MDD subjects. As for the BPD group, all three transporters showed trends similar to those observed in MDD, but the changes observed did not reach significance. We hypothesize that the decreased expression of the membrane glutamate transporters and the increased expression of the vesicular transporter in the hippocampus would affect the balance of the glutamatergic circuitry of the hippocampus, and that this effect may be a major contributor to depressive symptoms.
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Loss of sorting nexin 27 contributes to excitatory synaptic dysfunction by modulating glutamate receptor recycling in Downs syndrome.
Nat. Med.
PUBLISHED: 02-01-2013
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Sorting nexin 27 (SNX27), a brain-enriched PDZ domain protein, regulates endocytic sorting and trafficking. Here we show that Snx27(-/-) mice have severe neuronal deficits in the hippocampus and cortex. Although Snx27(+/-) mice have grossly normal neuroanatomy, we found defects in synaptic function, learning and memory and a reduction in the amounts of ionotropic glutamate receptors (NMDA and AMPA receptors) in these mice. SNX27 interacts with these receptors through its PDZ domain, regulating their recycling to the plasma membrane. We demonstrate a concomitant reduced expression of SNX27 and CCAAT/enhancer binding protein ? (C/EBP?) in Downs syndrome brains and identify C/EBP? as a transcription factor for SNX27. Downs syndrome causes overexpression of miR-155, a chromosome 21-encoded microRNA that negatively regulates C/EBP?, thereby reducing SNX27 expression and resulting in synaptic dysfunction. Upregulating SNX27 in the hippocampus of Downs syndrome mice rescues synaptic and cognitive deficits. Our identification of the role of SNX27 in synaptic function establishes a new molecular mechanism of Downs syndrome pathogenesis.
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Early effectiveness of isolated pectoralis minor tenotomy in selected patients with neurogenic thoracic outlet syndrome.
J. Vasc. Surg.
PUBLISHED: 02-01-2013
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This study evaluated the early effectiveness of isolated pectoralis minor tenotomy (PMT) in the surgical treatment of selected patients with neurogenic thoracic outlet syndrome (NTOS) compared with supraclavicular decompression (SCD; as scalenectomy, neurolysis, and first rib resection) plus PMT (SCD+PMT).
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A novel grading system for clear cell renal cell carcinoma incorporating tumor necrosis.
Am. J. Surg. Pathol.
PUBLISHED: 01-26-2013
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Grading of renal cell carcinoma (RCC) has prognostic significance, and there is recent consensus by the International Society of Urological Pathology (ISUP) that for clear cell and papillary RCC, grading should primarily be based on nucleolar prominence. Microscopic tumor necrosis also predicts outcome independent of tumor grading. This study was undertaken to assess whether the incorporation of microscopic tumor necrosis into the ISUP grading system provides survival information superior to ISUP grading alone. Data on 3017 patients treated surgically for clear cell RCC, 556 for papillary RCC, and 180 for chromophobe RCC were retrieved from the Mayo Clinic Registry. Median follow-up periods were 8.9, 9.7, and 8.5 years, respectively. Four proposed grades were defined: grade 1: ISUP grade 1+ISUP grade 2 without necrosis; grade 2: ISUP grade 2 with necrosis+ISUP grade 3 without necrosis; grade 3: ISUP grade 3 with necrosis+ISUP grade 4 without necrosis; grade 4: ISUP grade 4 with necrosis or sarcomatoid/rhabdoid tumors. There was a significant difference in survival between each of the grades for clear cell RCC, and the concordance index was superior to that of ISUP grading. The proposed grading system also outperformed the ISUP grading system when cases were stratified according to the TNM stage. Similar results were not obtained for papillary RCC or chromophobe RCC. We conclude that grading for clear cell RCC should be based on nucleolar prominence and necrosis, that ISUP grading should be used for papillary RCC, and that chromophobe RCC should not be graded.
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Understanding the effect of side groups in ionic liquids on carbon-capture properties: a combined experimental and theoretical effort.
Phys Chem Chem Phys
PUBLISHED: 01-24-2013
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Ionic liquids are an emerging class of materials with applications in a variety of fields. Steady progress has been made in the creation of ionic liquids tailored to specific applications. However, the understanding of the underlying structure-property relationships has been slower to develop. As a step in the effort to alleviate this deficiency, the influence of side groups on ionic liquid properties has been studied through an integrated approach utilizing synthesis, experimental determination of properties, and simulation techniques. To achieve this goal, a classical force field in the framework of OPLS/Amber force fields has been developed to predict ionic liquid properties accurately. Cu(I)-catalyzed click chemistry was employed to synthesize triazolium-based ionic liquids with diverse side groups. Values of densities were predicted within 3% of experimental values, whereas self-diffusion coefficients were underestimated by about an order of magnitude though the trends were in excellent agreement, the activation energy calculated in simulation correlates well with experimental values. The predicted Henry coefficient for CO(2) solubility reproduced the experimentally observed trends. This study highlights the importance of integrating experimental and computational approaches in property prediction and materials development, which is not only useful in the development of ionic liquids for CO(2) capture but has application in many technological fields.
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Determination of trace level cadmium in SRM 3280 Multivitamin/Multielement Tablets via isotope dilution inductively coupled plasma mass spectrometry.
Talanta
PUBLISHED: 01-23-2013
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Cadmium was quantified at 80.15±0.86 ng/g (mean±95% expanded uncertainty) in NIST SRM 3280 Multivitamin/Multielement Tablets, using isotope dilution mass spectrometry. The method described utilized various precipitation and solid-phase extraction separation methodologies to isolate Cd from Sn and Mo, present respectively, at 11.1±0.9 mg/kg and 70.7±4.5 mg/kg in the tablet matrix. This allowed for measurement of (111)Cd/(113)Cd and (111)Cd/(114)Cd isotope ratios using both quadrupole collision cell technology inductively coupled plasma mass spectrometry (Q-CCT-ICP-MS) and sector field (SF)-ICP-MS equipped with a desolvating nebulizer system to mitigate the MoO(+) and MoOH(+) molecular ion interferences that typically affect the envelope of Cd isotopes.
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Effects of stressor controllability on diurnal physiological rhythms.
Physiol. Behav.
PUBLISHED: 01-17-2013
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Disruptions in circadian and diurnal rhythms are associated with stress-related psychiatric disorders and stressor exposure can disrupt these rhythms. The controllability of the stressor can modulate various behavioral and neurochemical responses to stress. Uncontrollable, but not controllable, stress produces behaviors in rats that resemble symptoms of anxiety and depression. Whether acute stress-induced disruptions in physiological rhythms are sensitive to controllability of the stressor, however, remains unknown. To examine the role of controllability in diurnal rhythm disruption, adult male Sprague-Dawley rats were implanted with Data Sciences International (DSI) biotelemetry devices. Real-time measurements were obtained before, during and after exposure to a controllable or yoked uncontrollable stressor. Controllable and uncontrollable stress equally disrupted diurnal rhythms of locomotor activity and body temperature but not heart rate. The diurnal heart rate the day following stressor exposure was flattened to a greater extent and was significantly higher in rats with control over stress suggesting a relationship between stressor controllability and the heart rate response. Our results are consistent with the conclusion that acute stress-induced disruptions in diurnal physiological rhythms likely contribute little to the behavioral and affective consequences of stress that are sensitive to stressor controllability.
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Increased Occurrence of Valproic Acid-Induced Hyperammonemia in Carriers of T1405N Polymorphism in Carbamoyl Phosphate Synthetase 1 Gene.
ISRN Neurol
PUBLISHED: 01-01-2013
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Numerous cases of severe and life-threatening hyperammonemia (HA) related to the treatment of epileptic seizures with valproic acid (VPA) have been previously reported in the medical literature. The aim of this prospective, multicenter study was to verify the putative association between T1405 polymorphism and occurrence of VPA-induced HA in the cohort of 142 adult Caucasian patients with epilepsy treated with VPA for at least 1 year and with normal liver functions. The nonsynonymous T1405N polymorphism genotyping was performed by real-time TaqMan PCR genotyping. In addition to plasma ammonia level, concentrations of liver enzymes and total VPA were measured in plasma with standard laboratory methods. HA (defined as ammonia plasma level >65? ? mol/L) was observed in total of 11 (7.7%) of patients treated with VPA, and the carrier status for the investigated polymorphism was significantly (P = 0.009, odds ratio 5.4 with 95% confidence interval of 1.58-18.43) associated with the occurrence of HA. The results of this study support a notion that in the Caucasian patients with epilepsy undergoing VPA therapy, a T1405N (4217C > A, rs1047891) nonsynonymous variant was a significant risk factor for the occurrence of HA, even in patients with normal plasma levels of VPA.
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Acute and chronic glucocorticoid treatments regulate astrocyte-enriched mRNAs in multiple brain regions in vivo.
Front Neurosci
PUBLISHED: 01-01-2013
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Previous studies have primarily interpreted gene expression regulation by glucocorticoids in the brain in terms of impact on neurons; however, less is known about the corresponding impact of glucocorticoids on glia and specifically astrocytes in vivo. Recent microarray experiments have identified glucocorticoid-sensitive mRNAs in primary astrocyte cell culture, including a number of mRNAs that have reported astrocyte-enriched expression patterns relative to other brain cell types. Here, we have tested whether elevations of glucocorticoids regulate a subset of these mRNAs in vivo following acute and chronic corticosterone exposure in adult mice. Acute corticosterone exposure was achieved by a single injection of 10 mg/kg corticosterone, and tissue samples were harvested 2 h post-injection. Chronic corticosterone exposure was achieved by administering 10 mg/mL corticosterone via drinking water for 2 weeks. Gene expression was then assessed in two brain regions associated with glucocorticoid action (prefrontal cortex and hippocampus) by qPCR and by in situ hybridization. The majority of measured mRNAs regulated by glucocorticoids in astrocytes in vitro were similarly regulated by acute and/or chronic glucocorticoid exposure in vivo. In addition, the expression levels for mRNAs regulated in at least one corticosterone exposure condition (acute/chronic) demonstrated moderate positive correlation between the two conditions by brain region. In situ hybridization analyses suggest that select mRNAs are regulated by chronic corticosterone exposure specifically in astroctyes based on (1) similar general expression patterns between corticosterone-treated and vehicle-treated animals and (2) similar expression patterns to the pan-astrocyte marker Aldh1l1. Our findings demonstrate that glucocorticoids regulate astrocyte-enriched mRNAs in vivo and suggest that glucocorticoids regulate gene expression in the brain in a cell type-dependent fashion.
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Fragments of the bacterial toxin microcin B17 as gyrase poisons.
PLoS ONE
PUBLISHED: 01-01-2013
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Fluoroquinolones are very important drugs in the clinical antibacterial arsenal; their success is principally due to their mode of action: the stabilisation of a gyrase-DNA intermediate (the cleavage complex), which triggers a chain of events leading to cell death. Microcin B17 (MccB17) is a modified peptide bacterial toxin that acts by a similar mode of action, but is unfortunately unsuitable as a therapeutic drug. However, its structure and mechanism could inspire the design of new antibacterial compounds that are needed to circumvent the rise in bacterial resistance to current antibiotics. Here we describe the investigation of the structural features responsible for MccB17 activity and the identification of fragments of the toxin that retain the ability to stabilise the cleavage complex.
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Integrated green algal technology for bioremediation and biofuel.
Bioresour. Technol.
PUBLISHED: 08-20-2011
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Sustainable non-food energy biomass and cost-effective ways to produce renewable energy technologies from this biomass are continuously emerging. Algae are capable of producing lipids and hydrocarbons quickly and their photosynthetic abilities make them a promising candidate for an alternative energy source. In addition, their favorable carbon life cycle and a renewed focus on rural economic development are attractive factors. In this review the focus is mainly on the integrated approach of algae culture for bioremediation and oil-based biofuel production with mention of possible other value-added benefits of using algae for those purposes.
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Decreased proliferation of adult hippocampal stem cells during cocaine withdrawal: possible role of the cell fate regulator FADD.
Neuropsychopharmacology
PUBLISHED: 07-27-2011
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The current study uses an extended access rat model of cocaine self-administration (5-h session per day, 14 days), which elicits several features manifested during the transition to human addiction, to study the neural adaptations associated with cocaine withdrawal. Given that the hippocampus is thought to have an important role in maintaining addictive behavior and appears to be especially relevant to mechanisms associated with withdrawal, this study attempted to understand how extended access to cocaine impacts the hippocampus at the cellular and molecular levels, and how these alterations change over the course of withdrawal (1, 14, and 28 days). Therefore, at the cellular level, we examined the effects of cocaine withdrawal on cell proliferation (Ki-67+ and NeuroD+ cells) in the DG. At the molecular level, we employed a discovery approach with gene expression profiling in the DG to uncover novel molecules possibly implicated in the neural adaptations that take place during cocaine withdrawal. Our results suggest that decreased hippocampal cell proliferation might participate in the adaptations associated with drug removal and identifies 14 days as a critical time-point of cocaine withdrawal. At the 14-day time-point, gene expression profiling of the DG revealed the dysregulation of several genes associated with cell fate regulation, highlighting two new neurobiological correlates (Ascl-1 and Dnmt3b) that accompany cessation of drug exposure. Moreover, the results point to Fas-Associated protein with Death Domain (FADD), a molecular marker previously associated with the propensity to substance abuse and cocaine sensitization, as a key cell fate regulator during cocaine withdrawal. Identifying molecules that may have a role in the restructuring of the hippocampus following substance abuse provides a better understanding of the adaptations associated with cocaine withdrawal and identifies novel targets for therapeutic intervention.
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Mycobacterium tuberculosis triggers host type I IFN signaling to regulate IL-1? production in human macrophages.
J. Immunol.
PUBLISHED: 07-22-2011
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Mycobacterium tuberculosis is a virulent intracellular pathogen that survives in macrophages even in the presence of an intact adaptive immune response. Type I IFNs have been shown to exacerbate tuberculosis in mice and to be associated with disease progression in infected humans. Nevertheless, the mechanisms by which type I IFNs regulate the host response to M. tuberculosis infection are poorly understood. In this study, we show that M. tuberculosis induces an IFN-related gene expression signature in infected primary human macrophages, which is dependent on host type I IFN signaling as well as the mycobacterial virulence factor, region of difference-1. We further demonstrate that type I IFNs selectively limit the production of IL-1?, a critical mediator of immunity to M. tuberculosis. This regulation occurs at the level of IL1B mRNA expression, rather than caspase-1 activation or autocrine IL-1 amplification and appears to be preferentially used by virulent mycobacteria since avirulent M. bovis bacillus Calmette-Guérin (BCG) fails to trigger significant expression of type I IFNs or release of mature IL-1? protein. The latter property is associated with decreased caspase-1-dependent IL-1? maturation in the BCG-infected macrophages. Interestingly, human monocytes in contrast to macrophages produce comparable levels of IL-1? in response to either M. tuberculosis or BCG. Taken together, these findings demonstrate that virulent and avirulent mycobacteria employ distinct pathways for regulating IL-1? production in human macrophages and reveal that in the case of M. tuberculosis infection the induction of type I IFNs is a major mechanism used for this purpose.
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Ascl1-induced neuronal differentiation of P19 cells requires expression of a specific inhibitor protein of cyclic AMP-dependent protein kinase.
J. Neurochem.
PUBLISHED: 06-24-2011
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cAMP-dependent protein kinase (PKA) plays a critical role in nervous system development by modulating sonic hedgehog and bone morphogenetic protein signaling. In the current studies, P19 embryonic carcinoma cells were neuronally differentiated by expression of the proneural basic helix-loop-helix transcription factor Ascl1. After expression of Ascl1, but prior to expression of neuronal markers such as microtubule associated protein 2 and neuronal ?-tubulin, P19 cells demonstrated a large, transient increase in both mRNA and protein for the endogenous protein kinase inhibitor (PKI)?. PKI?-targeted shRNA constructs both reduced the levels of PKI? expression and blocked the neuronal differentiation of P19 cells. This inhibition of differentiation was rescued by transfection of a shRNA-resistant expression vector for the PKI? protein, and this rescue required the PKA-specific inhibitory sequence of the PKI? protein. PKI? played a very specific role in the Ascl1-mediated differentiation process as other PKI isoforms were unable to rescue the deficit conferred by shRNA-mediated knockdown of PKI?. Our results define a novel requirement for PKI? and its inhibition of PKA during neuronal differentiation of P19 cells.
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Stamping oriented molecular monolayers using liquid crystal inks.
Chem. Commun. (Camb.)
PUBLISHED: 06-07-2011
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Thermotropic liquid crystal (LC)-based inks are combined with patterned anchoring stamps to deposit organic monolayer films with simultaneous control over positional and molecular orientational order in a single step.
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IL-10 blocks the development of resistance to re-infection with Schistosoma mansoni.
PLoS Pathog.
PUBLISHED: 06-03-2011
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Despite effective chemotherapy to treat schistosome infections, re-infection rates are extremely high. Resistance to reinfection can develop, however it typically takes several years following numerous rounds of treatment and re-infection, and often develops in only a small cohort of individuals. Using a well-established and highly permissive mouse model, we investigated whether immunoregulatory mechanisms influence the development of resistance. Following Praziquantel (PZQ) treatment of S. mansoni infected mice we observed a significant and mixed anti-worm response, characterized by Th1, Th2 and Th17 responses. Despite the elevated anti-worm response in PBMCs, liver, spleen and mesenteric lymph nodes, this did not confer any protection from a secondary challenge infection. Because a significant increase in IL-10-producing CD4(+)CD44(+)CD25(+)GITR(+) lymphocytes was observed, we hypothesised that IL-10 was obstructing the development of resistance. Blockade of IL-10 combined with PZQ treatment afforded a greater than 50% reduction in parasite establishment during reinfection, compared to PZQ treatment alone, indicating that IL-10 obstructs the development of acquired resistance. Markedly enhanced Th1, Th2 and Th17 responses, worm-specific IgG1, IgG2b and IgE and circulating eosinophils characterized the protection. This study demonstrates that blocking IL-10 signalling during PZQ treatment can facilitate the development of protective immunity and provide a highly effective strategy to protect against reinfection with S. mansoni.
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Want to improve undergraduate thesis writing? Engage students and their faculty readers in scientific peer review.
CBE Life Sci Educ
PUBLISHED: 06-03-2011
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One of the best opportunities that undergraduates have to learn to write like a scientist is to write a thesis after participating in faculty-mentored undergraduate research. But developing writing skills doesnt happen automatically, and there are significant challenges associated with offering writing courses and with individualized mentoring. We present a hybrid model in which students have the structural support of a course plus the personalized benefits of working one-on-one with faculty. To optimize these one-on-one interactions, the course uses BioTAP, the Biology Thesis Assessment Protocol, to structure engagement in scientific peer review. By assessing theses written by students who took this course and comparable students who did not, we found that our approach not only improved student writing but also helped faculty members across the department--not only those teaching the course--to work more effectively and efficiently with student writers. Students who enrolled in this course were more likely to earn highest honors than students who only worked one-on-one with faculty. Further, students in the course scored significantly better on all higher-order writing and critical-thinking skills assessed.
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Fibroblast growth factor-2 (FGF2) augmentation early in life alters hippocampal development and rescues the anxiety phenotype in vulnerable animals.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 04-25-2011
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Individuals with mood disorders exhibit alterations in the fibroblast growth factor system, including reduced hippocampal fibroblast growth factor-2 (FGF2). It is difficult, however, to pinpoint whether these alterations are a cause or consequence of the disorder. The present study asks whether FGF2 administered the day after birth has long-lasting effects on hippocampal development and emotionality. We show that early-life FGF2 shifts the pace of neurogenesis, with an early acceleration around weaning followed by a deceleration in adulthood. This, in turn, results in a denser dentate gyrus with more neurons. To assess the impact of early-life FGF2 on emotionality, we use rats selectively bred for differences in locomotor response to novelty. Selectively bred low-responder (bLR) rats show low levels of novelty-induced locomotion and exhibit high levels of anxiety- and depression-like behavior compared with their selectively bred high-responder counterparts. Early-life FGF2 decreased anxiety-like behavior in highly anxious bLRs without altering other behaviors and without affecting high-responder rats. Laser capture microscopy of the dentate gyrus followed by microarray analysis revealed genes that were differentially expressed in bLRs exposed to early-life FGF2 vs. vehicle-treated bLRs. Some of the differentially expressed genes that have been positively associated with anxiety were down-regulated, whereas genes that promote cell survival were up-regulated. Overall, these results show a key role for FGF2 in the developmental trajectory of the hippocampus as well as the modulation of anxiety-like behavior in adulthood, and they point to potential downstream targets for the treatment of anxiety disorders.
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Negative regulation of Yap during neuronal differentiation.
Dev. Biol.
PUBLISHED: 04-14-2011
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Regulated proliferation and cell cycle exit are essential aspects of neurogenesis. The Yap transcriptional coactivator controls proliferation in a variety of tissues during development, and this activity is negatively regulated by kinases in the Hippo signaling pathway. We find that Yap is expressed in mitotic mouse retinal progenitors and it is downregulated during neuronal differentiation. Forced expression of Yap prolongs proliferation in the postnatal mouse retina, whereas inhibition of Yap by RNA interference (RNAi) decreases proliferation and increases differentiation. We show Yap is subject to post-translational inhibition in the retina, and also downregulated at the level of mRNA expression. Using a cell culture model, we find that expression of the proneural basic helix-loop-helix (bHLH) transcription factors Neurog2 or Ascl1 downregulates Yap mRNA levels, and simultaneously inhibits Yap protein via activation of the Lats1 and/or Lats2 kinases. Conversely, overexpression of Yap prevents proneural bHLH proteins from initiating cell cycle exit. We propose that mutual inhibition between proneural bHLH proteins and Yap is an important regulator of proliferation and cell cycle exit during mammalian neurogenesis.
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Mast cell tryptase deficiency attenuates mouse abdominal aortic aneurysm formation.
Circ. Res.
PUBLISHED: 04-14-2011
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Mast cells (MCs) contribute to the formation of abdominal aortic aneurysms (AAAs) by producing biologically active mediators. Tryptase is the most abundant MC granule protein and participates in MC activation, protease maturation, leukocyte recruitment, and angiogenesis-all processes critical to AAA pathogenesis.
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Antiviral activity of the hepatitis C virus polymerase inhibitor filibuvir in genotype 1-infected patients.
Hepatology
PUBLISHED: 04-14-2011
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More effective and better-tolerated therapies are needed for chronic hepatitis C virus (HCV) infection. Among the direct-acting anti-HCV agents in development is the nonstructural 5B protein (NS5B polymerase) non-nucleoside inhibitor filibuvir. We investigated the antiviral activity, pharmacokinetics, safety, and tolerability of multiple doses of filibuvir in treatment-naive and treatment-experienced patients who were chronically infected with HCV genotype 1 in two phase 1b clinical studies (study 1 was a randomized, placebo-controlled dose escalation study and study 2 was a nonrandomized, open-label study). The filibuvir doses evaluated ranged from 200-1400 mg daily, and the duration of dosing ranged from 3-10 days. Genotypic changes in the NS5B nucleotide sequence following short-term filibuvir therapy were also assessed. Filibuvir potently inhibited viral replication in a dose-dependent manner. Mean maximum HCV RNA change from baseline ranged from -0.97 log(10) IU/mL with filibuvir given at 100 mg twice daily to -2.30 log(10) IU/mL with filibuvir given at 700 mg twice daily in treatment-naive patients. In treatment-experienced patients, an HCV RNA reduction of 2.20 log(10) IU/mL was achieved with filibuvir given at 450 mg twice daily. Filibuvir was well tolerated in both studies. Adverse events were mild or moderate in severity. No discontinuations, serious adverse events, or deaths were reported. NS5B sequencing identified residue 423 as the predominant site of mutation after filibuvir dosing.
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Quantitative assessment of macrophage functions in repair and fibrosis.
Curr Protoc Immunol
PUBLISHED: 04-05-2011
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Macrophages play key roles in wound repair and fibrosis by regulating extracellular matrix turnover. Macrophages can process matrix components themselves, but also recruit and alter the functions of other cell types that directly build or degrade extracellular matrix. Classically activated macrophages (CAM, also called M1) tend to promote tissue injury while alternatively activated macrophages (AAM, also called M2) are often linked with the mechanisms of wound repair and fibrosis. However, rather than promoting collagen deposition, recent studies suggest that arginase-1-expressing AAM suppress chronic inflammation and fibrosis by inhibiting antigen-specific T cell responses. This unit describes methods to measure arginase activity in macrophages and whole tissues as well as assays to quantify the T cell suppressive activity of AAMs. Modified hydroxyproline and soluble collagen assays that can be used to quantify collagen levels in tissues and brochoalveolar lavage fluid are also described. The protocols in this unit should provide the investigator with all the necessary information required to measure arginase activity and to correlate the observed activity with the progression and resolution of fibrosis.
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Myocyte proliferation in the developing heart.
Dev. Dyn.
PUBLISHED: 04-01-2011
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Regulation of organ growth is critical during embryogenesis. At the cellular level, mechanisms controlling the size of individual embryonic organs include cell proliferation, differentiation, migration, and attrition through cell death. All these mechanisms play a role in cardiac morphogenesis, but experimental studies have shown that the major determinant of cardiac size during prenatal development is myocyte proliferation. As this proliferative capacity becomes severely restricted after birth, the number of cell divisions that occur during embryogenesis limits the growth potential of the postnatal heart. We summarize here current knowledge concerning regional control of myocyte proliferation as related to cardiac morphogenesis and dysmorphogenesis. There are significant spatial and temporal differences in rates of cell division, peaking during the preseptation period and then gradually decreasing toward birth. Analysis of regional rates of proliferation helps to explain the mechanics of ventricular septation, chamber morphogenesis, and the development of the cardiac conduction system. Proliferation rates are influenced by hemodynamic loading, and transduced by autocrine and paracrine signaling by means of growth factors. Understanding the biological response of the developing heart to such factors and physical forces will further our progress in engineering artificial myocardial tissues for heart repair and designing optimal treatment strategies for congenital heart disease.
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Leptin action via neurotensin neurons controls orexin, the mesolimbic dopamine system and energy balance.
Cell Metab.
PUBLISHED: 03-10-2011
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Leptin acts on leptin receptor (LepRb)-expressing neurons throughout the brain, but the roles for many populations of LepRb neurons in modulating energy balance and behavior remain unclear. We found that the majority of LepRb neurons in the lateral hypothalamic area (LHA) contain neurotensin (Nts). To investigate the physiologic role for leptin action via these LepRb(Nts) neurons, we generated mice null for LepRb specifically in Nts neurons (Nts-LepRbKO mice). Nts-LepRbKO mice demonstrate early-onset obesity, modestly increased feeding, and decreased locomotor activity. Furthermore, consistent with the connection of LepRb(Nts) neurons with local orexin (OX) neurons and the ventral tegmental area (VTA), Nts-LepRbKO mice exhibit altered regulation of OX neurons and the mesolimbic DA system. Thus, LHA LepRb(Nts) neurons mediate physiologic leptin action on OX neurons and the mesolimbic DA system, and contribute importantly to the control of energy balance.
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Teosinte inflorescence phytolith assemblages mirror Zea taxonomy.
PLoS ONE
PUBLISHED: 02-26-2011
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Molecular DNA analyses of the New World grass (Poaceae) genus Zea, comprising five species, has resolved taxonomic issues including the most likely teosinte progenitor (Zea mays ssp. parviglumis) of maize (Zea mays ssp. mays). However, archaeologically, little is known about the use of teosinte by humans both prior to and after the domestication of maize. One potential line of evidence to explore these relationships is opaline phytoliths produced in teosinte fruit cases. Here we use multidimensional scaling and multiple discriminant analyses to determine if rondel phytolith assemblages from teosinte fruitcases reflect teosinte taxonomy. Our results indicate that rondel phytolith assemblages from the various taxa, including subspecies, can be statistically discriminated. This indicates that it will be possible to investigate the archaeological histories of teosinte use pending the recovery of appropriate samples.
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Clinical validation of cutoff target ranges in newborn screening of metabolic disorders by tandem mass spectrometry: a worldwide collaborative project.
David M S McHugh, Cynthia A Cameron, Jose E Abdenur, Mahera Abdulrahman, Ona Adair, Shahira Ahmed Al Nuaimi, Henrik Åhlman, Jennifer J Allen, Italo Antonozzi, Shaina Archer, Sylvia Au, Christiane Auray-Blais, Mei Baker, Fiona Bamforth, Kinga Beckmann, Gessi Bentz Pino, Stanton L Berberich, Robert Binard, François Boemer, Jim Bonham, Nancy N Breen, Sandra C Bryant, Michele Caggana, S Graham Caldwell, Marta Camilot, Carlene Campbell, Claudia Carducci, Rohit Cariappa, Clover Carlisle, Ubaldo Caruso, Michela Cassanello, Ane Miren Castilla, Daisy E Castiñeiras Ramos, Pranesh Chakraborty, Ram Chandrasekar, Alfredo Chardon Ramos, David Cheillan, Yin-Hsiu Chien, Thomas A Childs, Petr Chrastina, Yuri Cleverthon Sica, Jose Angel Cocho de Juan, Maria Elena Colandre, Veronica Cornejo Espinoza, Gaetano Corso, Robert Currier, Denis Cyr, Noémi Czuczy, Oceania D'Apolito, Tim Davis, Monique G de Sain-van der Velden, Carmen Delgado Pecellin, Iole Maria Di Gangi, Cristina Maria Di Stefano, Yannis Dotsikas, Melanie Downing, Stephen M Downs, Bonifacio Dy, Mark Dymerski, Inmaculada Rueda, Bert Elvers, Roger Eaton, Barbara M Eckerd, Fatma El Mougy, Sarah Eroh, Mercedes Espada, Catherine Evans, Sandy Fawbush, Kristel F Fijolek, Lawrence Fisher, Leifur Franzson, Dianne M Frazier, Luciana R C Garcia, Maria Sierra García-Valdecasas Bermejo, Dimitar Gavrilov, Rosemarie Gerace, Giuseppe Giordano, Yolanda González Irazabal, Lawrence C Greed, Robert Grier, Elyse Grycki, Xuefan Gu, Fizza Gulamali-Majid, Arthur F Hagar, Lianshu Han, W Harry Hannon, Christa Haslip, Fayza Abdelhamid Hassan, Miao He, Amy Hietala, Leslie Himstedt, Gary L Hoffman, William Hoffman, Philis Hoggatt, Patrick V Hopkins, David M Hougaard, Kerie Hughes, Patricia R Hunt, Wuh-Liang Hwu, June Hynes, Isabel Ibarra-González, Cindy A Ingham, Maria Ivanova, Ward B Jacox, Catharine John, John P Johnson, Jon J Jonsson, Eszter Karg, David Kasper, Brenda Klopper, Dimitris Katakouzinos, Issam Khneisser, Detlef Knoll, Hirinori Kobayashi, Ronald Koneski, Viktor Kožich, Rasoul Kouapei, Dirk Kohlmueller, Ivo Kremensky, Giancarlo la Marca, Marcia Lavochkin, Soo-Youn Lee, Denis C Lehotay, Aída Lemes, Joyce Lepage, Barbara Lesko, Barry Lewis, Carol Lim, Sharon Linard, Martin Lindner, Michele A Lloyd-Puryear, Fred Lorey, Yannis L Loukas, Julie Luedtke, Neil Maffitt, J Fergall Magee, Adrienne Manning, Shawn Manos, Sandrine Marie, Sônia Marchezi Hadachi, Gregg Marquardt, Stephen J Martin, Dietrich Matern, Stephanie K Mayfield Gibson, Philip Mayne, Tonya D McCallister, Mark McCann, Julie McClure, James J McGill, Christine D McKeever, Barbara McNeilly, Mark A Morrissey, Paraskevi Moutsatsou, Eleanor A Mulcahy, Dimitris Nikoloudis, Bent Norgaard-Pedersen, Devin Oglesbee, Mariusz Oltarzewski, Daniela Ombrone, Jelili Ojodu, Vagelis Papakonstantinou, Sherly Pardo Reoyo, Hyung-Doo Park, Marzia Pasquali, Elisabetta Pasquini, Pallavi Patel, Kenneth A Pass, Colleen Peterson, Rolf D Pettersen, James J Pitt, Sherry Poh, Arnold Pollak, Cory Porter, Philip A Poston, Ricky W Price, Cecilia Queijo, Jonessy Quesada, Edward Randell, Enzo Ranieri, Kimiyo Raymond, John E Reddic, Alejandra Reuben, Charla Ricciardi, Piero Rinaldo, Jeff D Rivera, Alicia Roberts, Hugo Rocha, Geraldine Roche, Cheryl Rochman Greenberg, José María Egea Mellado, María Jesús Juan-Fita, Consuelo Ruiz, Margherita Ruoppolo, S Lane Rutledge, Euijung Ryu, Christine Saban, Inderneel Sahai, Maria Isabel Salazar García-Blanco, Pedro Santiago-Borrero, Andrea Schenone, Roland Schoos, Barb Schweitzer, Patricia Scott, Margretta R Seashore, Mary A Seeterlin, David E Sesser, Darrin W Sevier, Scott M Shone, Graham Sinclair, Victor A Skrinska, Eleanor L Stanley, Erin T Strovel, April L Studinski Jones, Sherlykutty Sunny, Zoltán Takáts, Tijen Tanyalcin, Francesca Teofoli, J Robert Thompson, Kathy Tomashitis, Mouseline Torquado Domingos, Jasmin Torres, Rosario Torres, Silvia Tortorelli, Sándor Túri, Kimberley Turner, Nick Tzanakos, Alf G Valiente, Hillary Vallance, Marcela Vela-Amieva, Laura Vilarinho, Ulrika von Döbeln, Marie-Françoise Vincent, B Chris Vorster, Michael S Watson, Dianne Webster, Sheila Weiss, Bridget Wilcken, Veronica Wiley, Sharon K Williams, Sharon A Willis, Michael Woontner, Katherine Wright, Raquel Yahyaoui, Seiji Yamaguchi, Melissa Yssel, Wendy M Zakowicz.
Genet. Med.
PUBLISHED: 02-18-2011
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To achieve clinical validation of cutoff values for newborn screening by tandem mass spectrometry through a worldwide collaborative effort.
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Diagnostic and therapeutic strategies for small abdominal aortic aneurysms.
Nat Rev Cardiol
PUBLISHED: 02-08-2011
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Abdominal aortic aneurysms (AAA) affect 5% of the population in developed countries and are characterized by progressive aortic dilatation with an unpredictable time course. This condition is more common in men than in women, and in smokers than in nonsmokers. If left untreated, AAA can result in aortic rupture and death. Pathologically, aortic extracellular matrix degradation, inflammation, and neovascularization are hallmarks of AAA. Diagnosis of AAA and subsequent surveillance utilize established aortic imaging methods, such as ultrasound, CT, and MRI. More-speculative diagnostic approaches include molecular and cellular imaging methods that interrogate the underlying pathological processes at work within the aneurysm. In this Review, we explore the current diagnostic and therapeutic strategies for the management of AAA. We also describe the diagnostic potential of new imaging techniques and therapeutic potential of new treatments for the management of small AAA.
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Positional compression of the axillary artery causing upper extremity thrombosis and embolism in the elite overhead throwing athlete.
J. Vasc. Surg.
PUBLISHED: 01-26-2011
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To describe the spectrum of axillary artery pathology seen in high-performance overhead athletes and the outcomes of current treatment.
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Total synthesis of microcin B17 via a fragment condensation approach.
Org. Lett.
PUBLISHED: 01-14-2011
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The total synthesis of the 43 amino acid antibacterial peptide Microcin B17 (MccB17) is described. The natural product was synthesized via a convergent approach from a heterocycle-derived peptide and peptide thioester fragments prepared via Fmoc-strategy solid phase peptide synthesis (SPPS). Final assembly was achieved in an efficient manner using two Ag(I)-assisted peptide ligation reactions to afford MccB17 in excellent overall yield.
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APP processing in Alzheimers disease.
Mol Brain
PUBLISHED: 01-07-2011
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An important pathological feature of Alzheimers disease (AD) is the presence of extracellular senile plaques in the brain. Senile plaques are composed of aggregations of small peptides called ?-amyloid (A?). Multiple lines of evidence demonstrate that overproduction/aggregation of A? in the brain is a primary cause of AD and inhibition of A? generation has become a hot topic in AD research. A? is generated from ?-amyloid precursor protein (APP) through sequential cleavages first by ?-secretase and then by ?-secretase complex. Alternatively, APP can be cleaved by ?-secretase within the A? domain to release soluble APP? and preclude A? generation. Cleavage of APP by caspases may also contribute to AD pathologies. Therefore, understanding the metabolism/processing of APP is crucial for AD therapeutics. Here we review current knowledge of APP processing regulation as well as the patho/physiological functions of APP and its metabolites.
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Eosinophilic pustular folliculitis: case report and review of the literature.
Cutis
PUBLISHED: 12-15-2010
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Eosinophilic pustular folliculitis (EPF) is a rare dermatosis characterized by recurrent outbreaks of papulopustular skin lesions mainly distributed in seborrheic areas. These eruptions often are associated with peripheral blood eosinophilia and occur mainly on the face, upper back, and upper extremities. There are 3 variants: classic EPF (Ofuji disease), immunosuppression-associated EPF, and infancy-associated EPF. We report a human immunodeficiency virus (HIV)-seronegative patient with classic EPF who responded to treatment with indomethacin.
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NGSQC: cross-platform quality analysis pipeline for deep sequencing data.
BMC Genomics
PUBLISHED: 12-02-2010
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While the accuracy and precision of deep sequencing data is significantly better than those obtained by the earlier generation of hybridization-based high throughput technologies, the digital nature of deep sequencing output often leads to unwarranted confidence in their reliability.
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Expression patterns of corticotropin-releasing factor, arginine vasopressin, histidine decarboxylase, melanin-concentrating hormone, and orexin genes in the human hypothalamus.
J. Comp. Neurol.
PUBLISHED: 10-02-2010
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The hypothalamus regulates numerous autonomic responses and behaviors. The neuroactive substances corticotropin-releasing factor (CRF), arginine-vasopressin (AVP), histidine decarboxylase (HDC), melanin-concentrating hormone (MCH), and orexin/hypocretins (ORX) produced in the hypothalamus mediate a subset of these processes. Although the expression patterns of these genes have been well studied in rodents, less is known about them in humans. We combined classical histological techniques with in situ hybridization histochemistry to produce both 2D and 3D images and to visually align and quantify expression of the genes for these substances in nuclei of the human hypothalamus. The hypothalamus was arbitrarily divided into rostral, intermediate, and caudal regions. The rostral region, containing the paraventricular nucleus (PVN), was defined by discrete localization of CRF- and AVP-expressing neurons, whereas distinct relationships between HDC, MCH, and ORX mRNA-expressing neurons delineated specific levels within the intermediate and caudal regions. Quantitative mRNA signal intensity measurements revealed no significant differences in overall CRF or AVP expression at any rostrocaudal level of the PVN. HDC mRNA expression was highest at the level of the premammillary area, which included the dorsomedial and tuberomammillary nuclei as well as the dorsolateral hypothalamic area. In addition, the overall intensity of hybridization signal exhibited by both MCH and ORX mRNA-expressing neurons peaked in distinct intermediate and caudal hypothalamic regions. These results suggest that human hypothalamic neurons involved in the regulation of the HPA axis display distinct neurochemical patterns that may encompass multiple local nuclei.
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Developmental programming: differential effects of prenatal testosterone excess on insulin target tissues.
Endocrinology
PUBLISHED: 09-15-2010
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Polycystic ovarian syndrome (PCOS) is the leading cause of infertility in reproductive-aged women with the majority manifesting insulin resistance. To delineate the causes of insulin resistance in women with PCOS, we determined changes in the mRNA expression of insulin receptor (IR) isoforms and members of its signaling pathway in tissues of adult control (n = 7) and prenatal testosterone (T)-treated (n = 6) sheep (100 mg/kg twice a week from d 30-90 of gestation), the reproductive/metabolic characteristics of which are similar to women with PCOS. Findings revealed that prenatal T excess reduced (P < 0.05) expression of IR-B isoform (only isoform detected), insulin receptor substrate-2 (IRS-2), protein kinase B (AKt), peroxisome proliferator-activated receptor-? (PPAR?), hormone-sensitive lipase (HSL), and mammalian target of rapamycin (mTOR) but increased expression of rapamycin-insensitive companion of mTOR (rictor), and eukaryotic initiation factor 4E (eIF4E) in the liver. Prenatal T excess increased (P < 0.05) the IR-A to IR-B isoform ratio and expression of IRS-1, glycogen synthase kinase-3? and -? (GSK-3? and -?), and rictor while reducing ERK1 in muscle. In the adipose tissue, prenatal T excess increased the expression of IRS-2, phosphatidylinositol 3-kinase (PI3K), PPAR?, and mTOR mRNAs. These findings provide evidence that prenatal T excess modulates in a tissue-specific manner the expression levels of several genes involved in mediating insulin action. These changes are consistent with the hypothesis that prenatal T excess disrupts the insulin sensitivity of peripheral tissues, with liver and muscle being insulin resistant and adipose tissue insulin sensitive.
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Magnetic resonance imaging and musculoskeletal ultrasonography detect and characterize covert inflammatory arthropathy in systemic sclerosis patients with arthralgia.
Rheumatology (Oxford)
PUBLISHED: 08-18-2010
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Arthropathy, particularly synovial inflammation in SSc, is not well characterized. We explored the role of MRI and musculoskeletal ultrasonography (MSUS) in detecting and characterizing synovial inflammation in SSc patients with arthralgia while comparing the two imaging modalities.
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Preparation and characterization of (CNSSS)2(A)2 (A = AsF6(-), SbF6(-), Sb2F11(-)) containing the O2-like 5,5-bis(1,2,3,4-trithiazolium) dication: the second example of a simple nonsterically hindered main-group diradical that retains its paramagnetism in
Inorg Chem
PUBLISHED: 08-12-2010
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The reaction of NC-CN with a 1:1 mixture of S(4)(MF(6))(2) and S(8)(MF(6))(2) (M = As, Sb) (stoichiometrically equivalent to four "S(3)MF(6)" units) results in the quantitative formation of S(3)NCCNS(3)(MF(6))(2) [7(MF(6))(2)], which is the thermodynamic sink in this reaction. The Sb(2)F(11)(-) salt 7(Sb(2)F(11))(2) is prepared by the addition of an excess of SbF(5) to 7(AsF(6))(2). Crystal structure determinations for all three salts show that 7(2+) can be viewed as two R-CNS(3)(+) radical cations joined together by a C-C single bond. The two rings are coplanar and in a trans orientation due to electrostatic N(delta-)...S(delta+) interactions. The classically bonded alternative (quinoidal structure), in which the octet rule is obeyed, is not observed and is much higher in energy based on calculated estimates and a simple comparison of pi bond energies. Calculated molecular orbitals (MOs) support this, showing that the MO corresponding to the quinoidal structure lies higher in energy than the nearly degenerate singly occupied MOs of 7(2+). The vibrational spectra of 7(2+) in all salts were assigned based on a normal-coordinate analysis and theoretical vibrational frequencies calculated at the PBE0/6-31G* level. In the solid state, 7(2+) is a planar disjoint diradical with essentially degenerate open-shell singlet and triplet states. The disjoint nature of the diradical cation 7(2+) is established by magnetic susceptibility studies of the Sb(2)F(11)(-) salt doped in an isomorphous diamagnetic host material (CNSNS)(2)(Sb(2)F(11))(2) [10(Sb(2)F(11))(2)]. Intramolecular spin coupling is extremely weak corresponding to a singlet-triplet gap (DeltaE(ST) = 2J) of <+/-2 cm(-1). CASPT2[12,12]/6-311G* calculations support a triplet ground state with a small singlet-triplet gap. The single-crystal electron paramagnetic resonance (EPR) of 7(Sb(2)F(11))(2) doped in 10(Sb(2)F(11))(2) is in agreement with the triplet state arising from the weak coupling between the unpaired electrons residing in p(pi) orbitals in each of the rings. Variable-temperature susceptibility data for bulk samples of 7(A)(2) (A = SbF(6)(-), AsF(6)(-), Sb(2)F(11)(-)) are analyzed by employing both 1D chain and 2D sheet magnetic models. These studies reveal significant intermolecular exchange approximating that of a 1D chain for the SbF(6)(-) salt with |J| = 32 cm(-1). The exchange coupling is on the same order of magnitude as that for the AsF(6)(-) salt, although in this case it is likely that there are complex exchange pathways where no particular one is dominant. Intermolecular exchange in the Sb(2)F(11)(-) salt is an order of magnitude weaker. In solution, the EPR spectrum of 7(2+) shows a broad triplet resonance as well as a sharp resonance that is tentatively attributed to a rotomer of the 7(2+)/anion pair, which is likely the origin of the green species given on dissolution of the red 7(2+) salts in SO(2)/AsF(3)/MF(5). We account for the many similarities between O(2) and 7(2+), which are the only simple nonsterically hindered nonmetal diradicals to retain their paramagnetism in the solid state. 7(2+) is also the first isolable, essentially sulfur-based diradical as evidenced by calculated spin densities.
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Adult health and relationship outcomes among women with abuse experiences during childhood.
Violence Vict
PUBLISHED: 06-23-2010
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Associations between child abuse and/or witnessing intimate partner violence (IPV) during childhood and womens health, adult IPV exposure, and health care use were examined. Randomly sampled insured women ages 18-64 (N = 3,568) completed a phone interview assessing childhood exposure to abuse and witnessing IPV, current health, and adult IPV exposure. Womens health care use was collected from automated health plan databases. Poor health status, higher prevalence of depression and IPV, and greater use of health care and mental health services were observed in women who had exposure to child abuse and witnessing IPV during childhood or child abuse alone, compared with women with no exposures. Women who had witnessed IPV without child abuse also had worse health and greater use of health services. Findings reveal adverse long-term and incremental effects of differing child abuse experiences on womens health and relationships.
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Carnitine palmitoyltransferase 1A (CPT1A) P479L prevalence in live newborns in Yukon, Northwest Territories, and Nunavut.
Mol. Genet. Metab.
PUBLISHED: 06-04-2010
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Carnitine palmitoyltransferase 1A (CPT1A), encoded by the gene CPT1A, is the hepatic isoform of CPT1 and is a major regulatory point in long-chain fatty acid oxidation. CPT1A deficiency confers risk for hypoketotic hypoglycaemia, hepatic encephalopathy, seizures, and sudden unexpected death in infancy (SUDI). It remains controversial whether the CPT1A gene variant, c.1436C>T (p.P479L), identified in Inuit, First Nations, and Alaska Native infants, causes susceptibility to decompensation, in particular during times of fever and intercurrent illness. Although newborn screening for the P479L variant occurs in some jurisdictions, background knowledge about the presence of the variant in Canadian Aboriginal populations is lacking. In an effort to understand the population implications of the variant in northern Canada, overall frequencies of the variant were assessed. Further studies are underway to determine associated risk. Ethics approval was obtained from university REBs, local research institutes, and with consultation with territorial Aboriginal groups. Newborn screening blood spots from all infants born in 2006 in the three territories were genotyped for the p.P479L variant. p.P479L (c.1436C>T) allele frequencies in the three territories were 0.02, 0.08, and 0.77 in Yukon (n=325), Northwest Territories (n=564), and Nunavut (n=695), respectively. Homozygosity rates were 0%, 3%, and 64%. Aboriginal status was available only in NWT, with allele frequencies of 0.04, 0.44, 0.00, and 0.01 for First Nations, Inuvialuit/Inuit, Métis, and non-Aboriginal populations. Although individual blood spots were not identified for Aboriginal ethnicity in Nunavut infants, ~90% of infants in Nunavut are born to Inuit women. The allele frequency and rate of homozygosity for the CPT1A P479L variant were high in Inuit and Inuvialuit who reside in northern coastal regions. The variant is present at a low frequency in First Nations populations, who reside in areas less coastal than the Inuit or Inuvialuit in the two western territories. The significance of the population and geographic distribution remains unclear, but the high population frequencies of the variant suggest a historically low penetrance for adverse outcomes. Further evidence is needed to determine if there is an increased risk for infant mortality and morbidity and whether newborn screening will be indicated on a population basis.
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Analysis of messenger RNA expression by in situ hybridization using RNA probes synthesized via in vitro transcription.
Methods
PUBLISHED: 06-01-2010
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The analysis of the spatial patterning of mRNA expression is critically important for assigning functional and physiological significance to a given gene product. Given the tens of thousands of mRNAs in the mammalian genome, a full assessment of individual gene functions would ideally be overlaid upon knowledge of the specific cell types expressing each mRNA. In situ hybridization approaches represent a molecular biological/histological method that can reveal cellular patterns of mRNA expression. Here, we present detailed procedures for the detection of specific mRNAs using radioactive RNA probes in tissue sections followed by autoradiographic detection. These methods allow for the specific and sensitive detection of spatial patterns of mRNA expression, thereby linking mRNA expression with cell type and function. Radioactive detection methods also facilitate semi-quantitative analyses of changes in mRNA gene expression.
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An analysis of net energy production and feedstock availability for biobutanol and bioethanol.
Bioresour. Technol.
PUBLISHED: 05-21-2010
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In this study, the potential of biobutanol was evaluated as an alternative to bioethanol which is currently the predominant liquid biofuel in the US. Life-cycle assessments (LCAs) suggest that the net energy generated during corn-to-biobutanol conversion is 6.53 MJ/L, which is greater than that of the corn-derived bioethanol (0.40 MJ/L). Additionally, replacing corn with lignocellulosic materials in bioethanol production can further increase the net energy to 15.90 MJ/L. Therefore, it was interesting to study the possibility of using domestically produced switchgrass, hybrid poplar, corn stover, and wheat straw as feedstocks to produce liquid biofuels in the US. By sustainable harvest based on current yields, these materials can be converted to 8.27 billion gallons of biobutanol replacing 7.55 billion gallons of gasoline annually. To further expand the scale, significant crop yield increases and appropriate land use changes are considered two major requirements.
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Direct transcriptional induction of Gadd45gamma by Ascl1 during neuronal differentiation.
Mol. Cell. Neurosci.
PUBLISHED: 03-23-2010
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The basic helix-loop-helix transcription factor Ascl1 plays a critical role in the intrinsic genetic program responsible for neuronal differentiation. Here, we describe a novel model system of P19 embryonic carcinoma cells with doxycycline-inducible expression of Ascl1. Microarray hybridization and real-time PCR showed that these cells demonstrated increased expression of many neuronal proteins in a time- and concentration-dependent manner. Interestingly, the gene encoding the cell cycle regulator Gadd45gamma was increased earliest and to the greatest extent following Ascl1 induction. Here, we provide the first evidence identifying Gadd45gamma as a direct transcriptional target of Ascl1. Transactivation and chromatin immunoprecipitation assays identified two E-box consensus sites within the Gadd45gamma promoter necessary for Ascl1 regulation, and demonstrated that Ascl1 is bound to this region within the Gadd45gamma promoter. Furthermore, we found that overexpression of Gadd45gamma itself is sufficient to initiate some aspects of neuronal differentiation independent of Ascl1.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.