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Wright MS, Ulrich MR, Fins JJ
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Guardianship and Clinical Research Participation: The Case of Wards with Disorders of Consciousness

KENNEDY INSTITUTE OF ETHICS JOURNAL 2017 MAR; 27(1):43-70
We review relevant federal law about research on human subjects and state laws on guardian authority to determine whether guardians can consent on behalf of their wards to participation in research. The Common Rule is silent on the issue as are most state guardianship laws. Our analysis shows significant variation in guardians' decision-making authority in the states that do regulate wards' participation in research. We consider how the appointment of guardians for patients with disorders of consciousness (DOC) impacts such patients' access to research. We assert that it is important that such persons be permitted to participate in research, so that their conditions and potential medical interventions can be studied, and that those with similar conditions can benefit from the knowledge gained from these studies. We argue that state guardianship laws should be adapted to specifically give guardians the authority to consent to research on behalf of wards who may be able to regain decisional capacity.
Bieniasz P
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Repurposing a Bacterial Immune System to Discover Antiviral Targets

NEW ENGLAND JOURNAL OF MEDICINE 2017 MAR 30; 376(13):1290-1291
The effect of new, easy-to-use tools for editing cellular genomes in medicine and biomedical science is difficult to overstate. The new method uses programmable DNA-cutting machinery from a bacterial immune system (CRISPR [clustered regularly interspaced short palindromic repeats]–Cas9), which can be repurposed for use in nearly any type of cell. With the use of CRISPR guides (i.e., CRISPR RNA that guides Cas9 to a specific location in the human genome), the Cas9 enzyme can be targeted to inactivate or edit specific genes in cultured cells or in laboratory animals. Perhaps one day — if technical and ethical constraints are addressed — this method will be used to treat human disease.
Nishimura Y, Gautam R, Chun TW, Sadjadpour R, Foulds KE, Shingai M, Klein F, Gazumyan A, Golijanin J, Donaldson M, Donau OK, Plishka RJ, Buckler-White A, Seaman MS, Lifson JD, Koup RA, Fauci AS, Nussenzweig MC, Martin MA
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Early antibody therapy can induce long-lasting immunity to SHIV

NATURE 2017 MAR 23; 543(7646):559-563
Highly potent and broadly neutralizing anti-HIV-1 antibodies (bNAbs) have been used to prevent and treat lentivirus infections in humanized mice, macaques, and humans(1-12). In immunotherapy experiments, administration of bNAbs to chronically infected animals transiently suppresses virus replication, which invariably returns to pre-treatment levels and results in progression to clinical disease. Here we show that early administration of bNAbs in a macaque simian/human immunodeficiency virus (SHIV) model is associated with very low levels of persistent viraemia, which leads to the establishment of T-cell immunity and resultant longterm infection control. Animals challenged with SHIVAD8-EO by mucosal or intravenous routes received a single 2-week course of two potent passively transferred bNAbs (3BNC117 and 10-1074 (refs 13, 14)). Viraemia remained undetectable for 56-177 days, depending on bNAb half-life in vivo. Moreover, in the 13 treated monkeys, plasma virus loads subsequently declined to undetectable levels in 6 controller macaques. Four additional animals maintained their counts of T cells carrying the CD4 antigen (CD4+) and very low levels of viraemia persisted for over 2 years. The frequency of cells carrying replication-competent virus was less than 1 per 106 circulating CD4(+) T cells in the six controller macaques. Infusion of a T-cell-depleting anti-CD8 beta monoclonal antibody to the controller animals led to a specific decline in levels of CD8(+) T cells and the rapid reappearance of plasma viraemia. In contrast, macaques treated for 15 weeks with combination anti-retroviral therapy, beginning on day 3 after infection, experienced sustained rebound plasma viraemia when treatment was interrupted. Our results show that passive immunotherapy during acute SHIV infection differs from combination anti-retroviral therapy in that it facilitates the emergence of potent CD8(+) T-cell immunity able to durably suppress virus replication.
Ruecker N, Jansen R, Trujillo C, Puckett S, Jayachandran P, Piroli GG, Frizzell N, Molina H, Rhee KY, Ehrt S
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Fumarase Deficiency Causes Protein and Metabolite Succination and Intoxicates Mycobacterium tuberculosis

CELL CHEMICAL BIOLOGY 2017 MAR 16; 24(3):306-315
Enzymes of central carbon metabolism are essential mediators of Mycobacterium tuberculosis (Mtb) physiology and pathogenicity, but are often perceived to lack sufficient species selectivity to be pursued as potential drug targets. Fumarase (Fum) is an enzyme of the canonical tricarboxylic acid cycle and is dispensable in many organisms. Transposon mutagenesis studies in Mtb, however, indicate that Fum is required for optimal growth. Here, we report the generation and characterization of a genetically engineered Mtb strain in which Fum expression is conditionally regulated. This revealed that Fum deficiency is bactericidal in vitro and during both the acute and chronic phases of mouse infection. This essentiality is linked to marked accumulations of fumarate resulting in protein and metabolite succination, a covalent modification of cysteine thiol residues. These results identify Mtb Fum as a potentially species-specific drug target whose inactivation may kill Mtb through a covalently irreversible form of metabolic toxicity.
Gleicher N, Kushnir VA, Darmon SK, Wang Q, Zhang L, Albertini DF, Barad DH
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New PCOS-like phenotype in older infertile women of likely autoimmune adrenal etiology with high AMH but low androgens

JOURNAL OF STEROID BIOCHEMISTRY AND MOLECULAR BIOLOGY 2017 MAR; 167(?):144-152
How anti-Mtillerian hormone (AMH) and testosterone (T) interrelate in infertile women is currently largely unknown. We, therefore, in a retrospective cohort study investigated how infertile women with high-AMH (AMH >= 75th quantile; n =144) and with normal-AMH (25th-75th quantile; n = 313), stratified for low-T (total testosterone <= 19.0 ng/dL), normal-T (19.0-29.0 ng/dL) and high-T (>29.0 ng/dL) phenotypically behaved. Patient age, follicle stimulating hormone (FSH), dehyroepiandrosterone (DHEA), DHEA sulphate (DHEAS), cortisol (C), adrenocorticotrophic hormone (ACTH), IVF outcomes, as well as inflammatory and immune panels were then compared between groups, with AMH and T as variables. We identified a previously unknown infertile PCOS-like phenotype, characterized by highAMH but, atypically, low-T, with predisposition toward autoimmunity. It presents with incompatible high-AMH and low-T (<19.0 ng/dL), is restricted to lean PCOS-like patients, presenting delayed for tertiary fertility services. Since also characterized by low DHEAS, low-T is likely of adrenal origina, and consequence of autoimmune adrenal insufficiency since also accompanied by low-C and evidence of autoimmunity. DHEA supplementation in such patients equalizes low- to normal-T and normalizes IVF cycle outcomes. Once recognized, this high-AMH/low-T phenotype is surprisingly common in tertiary fertility centers but, currently, goes unrecognized. Its likely adrenal autoimmune etiology offers interesting new directions for investigations of adrenals control over ovarian function via adrenal androgen production. (C) 2016 Elsevier Ltd. All rights reserved.
Meier JA, Hyun M, Cantwell M, Raza A, Mertens C, Raje V, Sisler J, Tracy E, Torres-Odio S, Gispert S, Shaw PE, Baumann H, Bandyopadhyay D, Takabe K, Larner AC
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Stress-induced dynamic regulation of mitochondrial STAT3 and its association with cyclophilin D reduce mitochondrial ROS production

SCIENCE SIGNALING 2017 MAR 28; 10(472):? Article eaag2588
Signal transducer and activator of transcription 3 (STAT3) is associated with various physiological and pathological functions, mainly as a transcription factor that translocates to the nucleus upon tyrosine phosphorylation induced by cytokine stimulation. In addition, a small pool of STAT3 resides in the mitochondria, where it serves as a sensor for various metabolic stressors including reactive oxygen species (ROS). Mitochondrially localized STAT3 largely exerts its effects through direct or indirect regulation of the activity of the electron transport chain (ETC). It has been assumed that the amounts of STAT3 in the mitochondria are static. We showed that various stimuli, including oxidative stress and cytokines, triggered a signaling cascade that resulted in a rapid loss of mitochondrially localized STAT3. Recovery of the mitochondrial pool of STAT3 over time depended on phosphorylation of Ser(727) in STAT3 and new protein synthesis. Under these conditions, mitochondrially localized STAT3 also became competent to bind to cyclophilin D (CypD). Binding of STAT3 to CypD was mediated by the amino terminus of STAT3, which was also important for reducing mitochondrial ROS production after oxidative stress. These results outline a role for mitochondrially localized STAT3 in sensing and responding to external stimuli.
Barbash S, Sakmar TP
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Length-dependent gene misexpression is associated with Alzheimer's disease progression

SCIENTIFIC REPORTS 2017 MAR 15; 7(?):? Article 190
Recent reports show transcription preference for long genes in neuronal tissues compared with non-neuronal tissues, and a gene-length dependent change in expression in the neurodevelopmental disease Rett syndrome (RTT). Whether the gene-length dependent changes in expression seen in RTT might also be seen in neurodegenerative diseases is not yet known. However, a reasonable hypothesis is that similar effects might be seen in neurodegenerative diseases as well as in RTT since a common general feature of both illnesses involves progressive dysfunction of synapses. Here, we demonstrate a clear length-dependent gene misexpression in the most prevalent neurodegenerative disease, Alzheimer's disease. We show that the effect is associated with disease progression and can be attributed specifically to neurons. In particular, we observed gene length-dependent down regulation on the level of the whole tissue and gene length-dependent up regulation on the level of single cells. Our analysis shows that a gene-length effect on expression can be found in degenerative neurological illnesses, such as Alzheimer's disease. Additional investigation to elucidate the precise mechanism underlying gene-length dependent changes in expression is warranted.
Andrade EC, Musante V, Horiuchi A, Matsuzaki H, Brody AH, Wu T, Greengard P, Taylor JR, Nairn AC
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ARPP-16 Is a Striatal-Enriched Inhibitor of Protein Phosphatase 2A Regulated by Microtubule-Associated Serine/Threonine Kinase 3 (Mast 3 Kinase)

JOURNAL OF NEUROSCIENCE 2017 MAR 8; 37(10):2709-2722
ARPP-16 (cAMP-regulated phospho-protein of molecular weight 16 kDa) is one of several small acid-soluble proteins highly expressed in medium spiny neurons of striatum that are phosphorylated in response to dopamine acting via D1 receptor/protein kinase A (PKA) signaling. We show here that ARPP-16 is also phosphorylated in vitro and in vivo by microtubule-associated serine/threonine kinase 3 (MAST3 kinase), an enzyme of previously unknown function that is enriched in striatum. We find that ARPP-16 interacts directly with the scaffolding A subunit of the serine/threonine protein phosphatase, PP2A, and that phosphorylation of ARPP-16 at Ser46 by MAST3 kinase converts the protein into a selective inhibitor of B55 alpha-and B56 delta-containing heterotrimeric forms of PP2A. Ser46 of ARPP-16 is phosphorylated to a high basal stoichiometry in striatum, suggestive of basal inhibition of PP2A in striatal neurons. In support of this hypothesis, conditional knock-out of ARPP-16 in CaMKII alpha :: cre/floxed ARPP-16/19 mice results in dephosphorylation of a subset of PP2A substrates including phospho-Thr75-DARPP-32, phospho-T308-Akt, and phospho-T202/Y204-ERK. Conditional knock-out of ARPP-16/19 is associated with increased motivation measured on a progressive ratio schedule of food reinforcement, yet an attenuated locomotor response to acute cocaine. Our previous studies have shown that ARPP-16 is phosphorylated at Ser88 by PKA. Activation of PKA in striatal slices leads to phosphorylation of Ser88, and this is accompanied by marked dephosphorylation of Ser46. Together, these studies suggest that phospho-Ser46-ARPP-16 acts to basally control PP2A in striatal medium spiny neurons but that dopamine acting via PKA inactivates ARPP-16 leading to selective potentiation of PP2A signaling.
Dunogue B, Pilmis B, Mahlaoui N, Elie C, Coignard-Biehler H, Amazzough K, Noel N, Salvator H, Catherinot E, Couderc LJ, Sokol H, Lanternier F, Fouyssac F, Bardet J, Bustamante J, Gougerot-Pocidalo MA, Barlogis V, Masseau A, Durieu I, Lecuit M, Suarez F, Fischer A, Blanche S, Hermine O, Lortholary O
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Chronic Granulomatous Disease in Patients Reaching Adulthood: A Nationwide Study in France

CLINICAL INFECTIOUS DISEASES 2017 MAR 15; 64(6):767-775
Background. Although prognosis of Chronic Granulomatous Disease (CGD) has greatly improved, few studies have focused on its long-term outcome. We studied the clinical course and sequelae of CGD patients diagnosed before age 16, at various adult time points. Method. Cross-sectional French nationwide retrospective study of patients screened through the National Reference Center for Primary Immunodeficiencies (CEREDIH) registry. Results. Eighty CGD patients (71 males [88.7%], 59 X-linked [73.7%], median age 23.9 years [minimum, 16.6; maximum, 59.9]) were included, Median ages at diagnosis and last follow-up were 2.52 and 23.9 years, respectively. Seven patients underwent hematopoietic stem cell transplantation. A total of 553 infections requiring hospitalization occurred in 2017 patient-years. The most common site of infection was pulmonary (31%). Aspergillus spp. (17%) and Staphylococcus aureus (10.7%) were the commonest pathogens. A total of 224 inflammatory episodes occurred in 71 patients, mainly digestive (50%). Their characteristics as well as their annual frequency did not vary before and after age 16. Main sequelae were a small adult height and weight and mild chronic restrictive respiratory failure. At age 16, only 53% of patients were in high school. After age 30 years, 9/13 patients were working. Ten patients died during adulthood. Conclusions. Adult CGD patients displayed similar characteristics and rates of severe infections and inflammatory episodes that those of childhood. The high rate of handicap has become a matter of medical and social consideration. Careful follow-up in centers of expertise is strongly recommended and an extended indication of curative treatment by HSCT should be considered.
Johnson ZL, Chen J
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Structural Basis of Substrate Recognition by the Multidrug Resistance Protein MRP1

CELL 2017 MAR 9; 168(6):1075-1085.e9
The multidrug resistance protein MRP1 is an ATP-binding cassette (ABC) transporter that confers resistance to many anticancer drugs and plays a role in the disposition and efficacy of several opiates, antidepressants, statins, and antibiotics. In addition, MRP1 regulates redox homeostasis, inflammation, and hormone secretion. Using electron cryomicroscopy, we determined the molecular structures of bovine MRP1 in two conformations: an apo form at 3.5 angstrom without any added substrate and a complex form at 3.3 angstrom with one of its physiological substrates, leukotriene C-4. These structures show that by forming a single bipartite binding site, MRP1 can recognize a spectrum of substrates with different chemical structures. We also observed large conformational changes induced by leukotriene C-4, explaining how substrate binding primes the transporter for ATP hydrolysis. Structural comparison of MRP1 and P-glycoprotein advances our understanding of the common and unique properties of these two important molecules in multidrug resistance to chemotherapy.