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Found 37769 matches. Displaying 5211-5220
Chait BT, Cadene M, Olinares PD, Rout MP, Shi Y
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Revealing Higher Order Protein Structure Using Mass Spectrometry

JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2016 JUN; 27(6):952-965
The development of rapid, sensitive, and accurate mass spectrometric methods for measuring peptides, proteins, and even intact protein assemblies has made mass spectrometry (MS) an extraordinarily enabling tool for structural biology. Here, we provide a personal perspective of the increasingly useful role that mass spectrometric techniques are exerting during the elucidation of higher order protein structures. Areas covered in this brief perspective include MS as an enabling tool for the high resolution structural biologist, for compositional analysis of endogenous protein complexes, for stoichiometry determination, as well as for integrated approaches for the structural elucidation of protein complexes. We conclude with a vision for the future role of MS-based techniques in the development of a multi-scale molecular microscope.
Forgacs PB, Fridman EA, Goldfine AM, Schiff ND
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Isolation Syndrome after Cardiac Arrest and Therapeutic Hypothermia

FRONTIERS IN NEUROSCIENCE 2016 JUN 9; 10(?):? Article 259
Here, we present the first description of an isolation syndrome in a patient who suffered prolonged cardiac arrest and underwent a standard therapeutic hypothermia protocol. Two years after the arrest, the patient demonstrated no motor responses to commands, communication capabilities, or visual tracking at the bedside. However, resting neuronal metabolism and electrical activity across the entire anterior forebrain was found to be normal despite severe structural injuries to primary motor, parietal, and occipital cortices. In addition, using quantitative electroencephalography, the patient showed evidence for willful modulation of brain activity in response to auditory commands revealing covert conscious awareness. A possible explanation for this striking dissociation in this patient is that altered neuronal recovery patterns following therapeutic hypothermia may lead to a disproportionate preservation of anterior forebrain cortico-thalamic circuits even in the setting of severe hypoxic injury to other brain areas. Compared to recent reports of other severely brain-injured subjects with such dissociation of clinically observable (overt) and covert behaviors, we propose that this case represents a potentially generalizable mechanism producing an isolation syndrome of blindness, motor paralysis, and retained cognition as a sequela of cardiac arrest and therapeutic hypothermia. Our findings further support that highly-preserved anterior cortico-thalamic integrity is associated with the presence of conscious awareness independent from the degree of injury to other brain areas.
Papp KA, Krueger JG, Feldman SR, Langley RG, Thaci D, Torii H, Tyring S, Wolk R, Gardner A, Mebus C, Tan HM, Luo YC, Gupta P, Mallbris L, Tatulych S
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Tofacitinib, an oral Janus kinase inhibitor, for the treatment of chronic plaque psoriasis: Long-term efficacy and safety results from 2 randomized phase-III studies and 1 open-label long-term extension study

JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY 2016 MAY; 74(5):841-850
Background: Tofacitinib is an oral Janus kinase inhibitor being investigated for psoriasis. Objectives:We sought to report longer-term tofacitinib efficacy and safety in patients with moderate to severe psoriasis. Methods: Data from 2 identical phase-III studies, Oral-treatment Psoriasis Trial Pivotal 1 and 2, were pooled with data from these patients in an ongoing open-label long-term extension study. Patients (n = 1861) were randomized 2:2:1 to tofacitinib 5 mg, 10 mg, or placebo twice daily (BID). At week 16, placebo patients were rerandomized to tofacitinib. Pivotal study participants could enroll into the long-term extension where they received tofacitinib at 10 mg BID for 3 months, after which dosing could be 5 or 10 mg BID. Results: At week 28, the proportions of patients randomized to tofacitinib 5 and 10 mg BID achieving 75% or greater reduction in Psoriasis Area and Severity Index score from baseline were 55.6% and 68.8%, and achieving Physician Global Assessment of clear or almost clear were 54.7% and 65.9%. Efficacy was maintained in most patients through 24 months. Serious adverse events and discontinuations because of adverse events were reported in less than 11% of patients over 33 months of tofacitinib exposure. Limitations: There was no dose comparison beyond week 52. Conclusions: Oral tofacitinib demonstrated sustained efficacy in patients with psoriasis through 2 years, with 10 mg BID providing greater efficacy than 5 mg BID. No unexpected safety findings were observed.
Rothschild JB, Tsimiklis P, Siggia ED, Francois P
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Predicting Ancestral Segmentation Phenotypes from Drosophila to Anopheles Using In Silico Evolution

PLOS GENETICS 2016 MAY; 12(5):? Article e1006052
Molecular evolution is an established technique for inferring gene homology but regulatory DNA turns over so rapidly that inference of ancestral networks is often impossible. In silico evolution is used to compute the most parsimonious path in regulatory space for anteriorposterior patterning linking two Dipterian species. The expression pattern of gap genes has evolved between Drosophila (fly) and Anopheles (mosquito), yet one of their targets, eve, has remained invariant. Our model predicts that stripe 5 in fly disappears and a new posterior stripe is created in mosquito, thus eve stripe modules 3+7 and 4+6 in fly are homologous to 3+6 and 4+5 in mosquito. We can place Clogmia on this evolutionary pathway and it shares the mosquito homologies. To account for the evolution of the other pair-rule genes in the posterior we have to assume that the ancestral Dipterian utilized a dynamic method to phase those genes in relation to eve.
Georgoudaki AM, Prokopec KE, Boura VF, Hellqvist E, Sohn S, Ostling J, Dahan R, Harris RA, Rantalainen M, Klevebring D, Sund M, Brage SE, Fuxe J, Rolny C, Li FB, Ravetch JV, Karlsson MCI
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Reprogramming Tumor-Associated Macrophages by Antibody Targeting Inhibits Cancer Progression and Metastasis

CELL REPORTS 2016 MAY 31; 15(9):2000-2011
Tumors are composed of multiple cell types besides the tumor cells themselves, including innate immune cells such as macrophages. Tumor-associated macrophages (TAMs) are a heterogeneous population of myeloid cells present in the tumor microenvironment (TME). Here, they contribute to immunosuppression, enabling the establishment and persistence of solid tumors as well as metastatic dissemination. We have found that the pattern recognition scavenger receptor MARCO defines a subtype of suppressive TAMs and is linked to clinical outcome. An anti-MARCO monoclonal antibody was developed, which induces anti-tumor activity in breast and colon carcinoma, as well as in melanoma models through reprogramming-TAM-populations to a pro-inflammatory phenotype and increasing tumor immunogenicity. This anti-tumor activity is dependent on the inhibitory Fc-receptor, Fc gamma RIIB, and also enhances the efficacy of checkpoint therapy. These results demonstrate that immunotherapies using antibodies designed to modify myeloid cells of the TME represent a promising mode of cancer treatment.
Gautam R, Nishimura Y, Pegu A, Nason MC, Klein F, Gazumyan A, Golijanin J, Buckler-White A, Sadjadpour R, Wang KY, Mankoff Z, Schmidt SD, Lifson JD, Mascola JR, Nussenzweig MC, Martin MA
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A single injection of anti-HIV-1 antibodies protects against repeated SHIV challenges

NATURE 2016 MAY 5; 533(7601):105-109
Despite the success of potent anti-retroviral drugs in controlling human immunodeficiency virus type 1 (HIV-1) infection, little progress has been made in generating an effective HIV-1 vaccine. Although passive transfer of anti-HIV-1 broadly neutralizing antibodies can protect mice or macaques against a single high-dose challenge with HIV or simian/human (SIV/HIV) chimaeric viruses (SHIVs) respectively(1-8), the long-term efficacy of a passive antibody transfer approach for HIV-1 has not been examined. Here we show, on the basis of the relatively long-term protection conferred by hepatitis A immune globulin, the efficacy of a single injection (20 mg kg(-1)) of four anti-HIV-1-neutralizing monoclonal antibodies (VRC01, VRC01-LS, 3BNC117, and 10-1074 (refs 9-12)) in blocking repeated weekly low-dose virus challenges of the clade B SHIVAD8. Compared with control animals, which required two to six challenges (median = 3) for infection, a single broadly neutralizing antibody infusion prevented virus acquisition for up to 23 weekly challenges. This effect depended on antibody potency and half-life. The highest levels of plasma-neutralizing activity and, correspondingly, the longest protection were found in monkeys administered the more potent antibodies 3BNC117 and 10-1074 (median = 13 and 12.5 weeks, respectively). VRC01, which showed lower plasma-neutralizing activity, protected for a shorter time (median = 8 weeks). The introduction of a mutation that extends antibody half-life into the crystallizable fragment (Fc) domain of VRC01 increased median protection from 8 to 14.5 weeks. If administered to populations at high risk of HIV-1 transmission, such an immunoprophylaxis regimen could have a major impact on virus transmission.
Nguyen A, Yoshida M, Goodarzi H, Tavazoie SF
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Highly variable cancer subpopulations that exhibit enhanced transcriptome variability and metastatic fitness

NATURE COMMUNICATIONS 2016 MAY; 7(?):? Article 11246
Individual cells within a tumour can exhibit distinct genetic and molecular features. The impact of such diversification on metastatic potential is unknown. Here we identify clonal human breast cancer subpopulations that display different levels of morphological and molecular diversity. Highly variable subpopulations are more proficient at metastatic colonization and chemotherapeutic survival. Through single-cell RNA-sequencing, inter-cell transcript expression variability is identified as a defining feature of the highly variable subpopulations that leads to protein-level variation. Furthermore, we identify high variability in the spliceosomal machinery gene set. Engineered variable expression of the spliceosomal gene SNRNP40 promotes metastasis, attributable to cells with low expression. Clinically, low SNRNP40 expression is associated with metastatic relapse. Our findings reveal transcriptomic variability generation as a mechanism by which cancer subpopulations can diversify gene expression states, which may allow for enhanced fitness under changing environmental pressures encountered during cancer progression.
Almey A, Milner TA, Brake WG
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Estrogen receptor alpha and G-protein coupled estrogen receptor 1 are localized to GABAergic neurons in the dorsal striatum

NEUROSCIENCE LETTERS 2016 MAY 27; 622(?):118-123
Estrogens affect dopamine transmission in the striatum, increasing dopamine availability, maintaining D2 receptor density, and reducing the availability of the dopamine transporter. Some of these effects of estrogens are rapid, suggesting that they are mediated by membrane associated receptors. Recently our group demonstrated that there is extra-nuclear labeling for ER alpha, ER beta, and GPER1 in the striatum, but that ER alpha and GPER1 are not localized to dopaminergic neurons in this region. GABAergic neurons are the most common type of neuron in the striatum, and changes in GABA transmission affect dopamine transmission. Thus, to determine whether ER alpha or GPER1 are localized to GABAergic neurons, we double labeled the striatum with antibodies for ER alpha or GPER1 and GABA and examined them using electron microscopy. Ultrastructural analysis revealed that ER alpha and GPER1 are localized exclusively to extranuclear sites in the striatum, and 35% of the dendrites and axon terminals labeled for these receptors contain GABA immunoreactivity. Binding at membrane-associated ER alpha and GPER1 could account for rapid estrogen-induced decreases in GABA transmission in the striatum, which, in turn, could affect dopamine transmission in this region. (C) 2016 Elsevier Ireland Ltd. All rights reserved.
Gagnidze K, Hajdarovic KH, Moskalenko M, Karatsoreos IN, McEwen BS, Bulloch K
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Nuclear receptor REV-ERB alpha mediates circadian sensitivity to mortality in murine vesicular stomatitis virus-induced encephalitis

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 2016 MAY 17; 113(20):5730-5735
Certain components and functions of the immune system, most notably cytokine production and immune cell migration, are under circadian regulation. Such regulation suggests that circadian rhythms may have an effect on disease onset, progression, and resolution. In the vesicular stomatitis virus (VSV)-induced encephalitis model, the replication, caudal penetration, and survivability of intranasally applied VSV depends on both innate and adaptive immune mechanisms. In the current study, we investigated the effect of circadian time of infection on the progression and outcome of VSV-induced encephalitis and demonstrated a significant decrease in the survival rate in mice infected at the start of the rest cycle, zeitgeber time 0 (ZT0). The lower survival rate in these mice was associated with higher levels of circulating chemokine (C-C motif) ligand 2 (CCL2), a greater number of peripherally derived immune cells accumulating in the olfactory bulb (OB), and increased production of proinflammatory cytokines, indicating an immune-mediated pathology. We also found that the acrophase of molecular circadian clock component REV-ERB alpha mRNA expression in the OB coincides with the start of the active cycle, ZT12, when VSV infection results in a more favorable outcome. This result led us to hypothesize that REV-ERB alpha may mediate the circadian effect on survival following VSV infection. Blocking REV-ERB alpha activity before VSV administration resulted in a significant increase in the expression of CCL2 and decreased survival in mice infected at the start of the active cycle. These data demonstrate that REV-ERB alpha-mediated inhibition of CCL2 expression during viral- induced encephalitis may have a protective effect.
Kaneto CM, Lima PSP, Zanette DL, Oliveira TYK, Pereira FD, Lorenzi JCC, dos Santos JL, Prata KL, Neto JMP, de Paula FJA, Silva WA
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Osteoblastic differentiation of bone marrow mesenchymal stromal cells in Bruck Syndrome

BMC MEDICAL GENETICS 2016 MAY 4; 17(?):? Article 38
Background: Osteogenesis Imperfecta (OI) (OMIM % 259450) is a heterogeneous group of inherited disorders characterized by increased bone fragility, with clinical severity ranging from mild to lethal. The majority of OI cases are caused by mutations in COL1A1 or COL1A2. Bruck Syndrome (BS) is a further recessively-inherited OI-like phenotype in which bone fragility is associated with the unusual finding of pterygia and contractures of the large joints. Notably, several studies have failed to show any abnormalities in the biosynthesis of collagen 1 in BS patientes. Evidence was obtained for a specific defect of the procollagen telopeptide lysine hydroxylation in BS, whereas mutations in the gene PLOD2 have been identified. Recently, several studies described FKBP10 mutations in OI-like and BS patients, suggesting that FKBP10 is a bonafide BS locus. Methods: We analyzed the coding region and intron/exon boundaries of COL1A1, COL1A2, PLOD2 and FKBP10 genes by sequence analysis using an ABI PRISM 3130 automated sequencer and Big Dye Terminator Sequencing protocol. Mononuclear cells obtained from the bone marrow of BS, OI patients and healthy donors were cultured and osteogenic differentiation was induced. The gene expression of osteoblast specific markers were also evaluated during the osteoblastic differentiation of mesenchymal stem cell (MSC) by qRT-PCR using an ABI7500 Sequence Detection System. Results: No mutations in COL1A1, COL1A2 or PLOD2 were found in BS patient. We found a homozygous 1-base-pair duplication (c.831dupC) that is predicted to produce a translational frameshift mutation and a premature protein truncation 17 aminoacids downstream (p.Gly278ArgfsX95). The gene expression of osteoblast specific markers BGLAP, COL1A1, MSX2, SPARC and VDR was evaluated by Real Time RT-PCR during differentiation into osteoblasts and results showed similar patterns of osteoblast markers expression in BS and healthy controls. On the other hand, when compared with OI patients, the expression pattern of these genes was found to be different. Conclusions: Our work suggests that the gene expression profiles observed during mesenchymal stromal cell differentiation into osteoblast are distinct in BS patients as compared to OI patients. The present study shows for the first time that genes involved in osteogenesis are differentially expressed in BS and OI patients.