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981.
Matthias Fassler Michael Zocher Sebastian Klare Alerie Guzman De La Fuente Johanna Scheuermann Anja Capell Christian Haass Christina Valkova Anbazhagan Veerappan Dirk Schneider Christoph Kaether 《Traffic (Copenhagen, Denmark)》2010,11(2):250-258
γ‐Secretase is critically involved in the Notch pathway and in Alzheimer's disease. The four subunits of γ‐secretase assemble in the endoplasmic reticulum (ER) and unassembled subunits are retained/retrieved to the ER by specific signals. We here describe a novel ER‐retention/retrieval signal in the transmembrane domain (TMD) 4 of presenilin 1, a subunit of γ‐secretase. TMD4 also is essential for complex formation, conferring a dual role for this domain. Likewise, TMD1 of Pen2 is bifunctional as well. It carries an ER‐retention/retrieval signal and is important for complex assembly by binding to TMD4. The two TMDs directly interact with each other and mask their respective ER‐retention/retrieval signals, allowing surface transport of reporter proteins. Our data suggest a model how assembly of Pen2 into the nascent γ‐secretase complex could mask TMD‐based ER‐retention/retrieval signals to allow plasma membrane transport of fully assembled γ‐secretase. 相似文献
982.
Fernández-Mendoza Julio Ilioudi Christina Montes Maria Isabel Olavarrieta-Bernardino Sara Aguirre-Berrocal Acacia De La Cruz-Troca Juan José Vela-Bueno Antonio 《Sleep and biological rhythms》2010,8(1):52-62
Sleep and Biological Rhythms - The aim of this study was to investigate whether evening circadian preference, as measured by the Horne and Östberg questionnaire, is associated with disrupted... 相似文献
983.
Stefano La Rosa Davide Vigetti Claudia Placidi Giovanna Finzi Silvia Uccella Moira Clerici Barbara Bartolini Ileana Carnevali Marco Losa Carlo Capella 《The journal of histochemistry and cytochemistry》2010,58(10):881-889
Carboxyl ester lipase (CEL) is an enzyme that hydrolyzes a wide variety of lipid substrates, including ceramides, which are known to show inhibitory regulation of pituitary hormone secretion in experimental models. Because no studies on CEL expression in human pituitary and pituitary adenomas have been reported in the literature, we investigated CEL expression in 10 normal pituitary glands and 86 well-characterized pituitary adenomas [12 FSH/LH cell, 17 α-subunit/null cell, 6 TSH cell, 21 ACTH cell, 11 prolactin (PRL) cell, and 19 GH cell adenomas] using IHC, immunoelectron microscopy, Western blotting, and quantitative RT-PCR. In normal adenohypophysis, CEL was localized in GH, ACTH, and TSH cells. In adenomas, it was mainly found in functioning GH, ACTH, and TSH tumors, whereas its expression was poor in the corresponding silent adenomas and was lacking in FSH/LH cell, null cell, and PRL cell adenomas. Ultrastructurally, CEL was localized in secretory granules close to their membranes. This is the first study demonstrating CEL expression in normal human pituitary glands and in functioning GH, ACTH, and TSH adenomas. Considering that CEL hydrolyzes ceramides, inactivating their inhibitory function on pituitary hormone secretion, our findings suggest a possible role of CEL in the regulation of hormone secretion in both normal and adenomatous pituitary cells. (J Histochem Cytochem 58:881–889, 2010) 相似文献
984.
Moffat JM Handel A Doherty PC Turner SJ Thomas PG La Gruta NL 《Journal of immunology (Baltimore, Md. : 1950)》2010,185(11):6850-6856
Cytokine polyfunctionality has recently emerged as a correlate of effective CTL immunity to viruses and tumors. Although the determinants of polyfunctionality remain unclear, there are published instances of a link between the production of multiple effector molecules and the peptide plus MHC class I molecule avidity of T cell populations. Influenza A virus infection of C57BL/6J mice induces CTL populations specific for multiple viral epitopes, each with varying proportions of monofunctional (IFN-γ(+) only) or polyfunctional (IFN-γ(+)TNF-α(+)IL-2(+)) CTLs. In this study, we probe the link between TCR avidity and polyfunctionality for two dominant influenza epitopes (D(b)NP(366) and D(b)PA(224)) by sequencing the TCR CDR3β regions of influenza-specific IFN-γ(+) versus IFN-γ(+)IL-2(+) cells, or total tetramer(+) versus high-avidity CTLs (as defined by the peptide plus MHC class I molecule-TCR dissociation rate). Preferential selection for particular clonotypes was evident for the high-avidity D(b)PA(224)-specific set but not for any of the other subsets examined. These data suggest that factors other than TCRβ sequence influence cytokine profiles and demonstrate no link between differential avidity and polyfunctionality. 相似文献
985.
Zoster sine herpete is a particular form of varicella zoster virus (VZV) infection characterized by segmental pain and dysesthesia, without any cutaneous lesions ever becoming perceptible. This report describes the case of a female patient, presenting with intercostal pain associated with a single papulo-vesicular lesion localized within the same area. Thanks to such a lesion, real time-polymerase chain reaction (PCR) analysis on vesicle fluid swab was possible, thus revealing a significant number of VZV genome copies. This innovative tool has proven essential to diagnose this abortive form of herpes zoster, which would otherwise have remained unidentified. 相似文献
986.
Vinayakumar Gedi Kumaresan Jayaraman Satish Kalme Hye-Yeon Park Hae-Chul Park Im-Joung La Hoh-Gyu Hahn Moon-Young Yoon 《Biochimica et Biophysica Acta - Proteins and Proteomics》2010,1804(6):1369-1375
Acetohydroxyacid synthase (AHAS), a potential target for antimicrobial agents, catalyzes the first common step in the biosynthesis of the branched-chain amino acids. The genes of both catalytic and regulatory subunits of AHAS from Bacillus anthracis (Bantx), a causative agent of anthrax, were cloned, overexpressed in Escherichiacoli, and purified to homogeneity. To develop novel anti-anthracis drugs that inhibit AHAS, a chemical library was screened, and four chemicals, AVS2087, AVS2093, AVS2387, and AVS2236, were identified as potent inhibitors of catalytic subunit with IC50 values of 1.0 ± 0.02, 1.0 ± 0.04, 2.1 ± 0.12, and 2.0 ± 0.08 µM, respectively. Further, these four chemicals also showed strong inhibition against reconstituted AHAS with IC50 values of 0.05 ± 0.002, 0.153 ± 0.004, 1.30 ± 0.10, and 1.29 ± 0.40 µM, respectively. The basic scaffold of the AVS group consists of 1-pyrimidine-2-yl-1H-[1,2,4]triazole-3-sulfonamide. The potent inhibitor, AVS2093 showed the lowest binding energy, − 8.52 kcal/mol and formed a single hydrogen bond with a distance of 1.973 ?. As the need for novel antibiotic classes to combat bacterial drug resistance increases, the screening of new compounds that act against Bantx-AHAS shows that AHAS is a good target for new anti-anthracis drugs. 相似文献
987.
José Luis Beristain Hernández Erick Servín Torres Alejandro Sosa Caballero José Arturo Velázquez García Roger Pozzo Bobarín Germán Delgadillo Teyer Ignacio Serrano Galeana Alfredo Márquez Hernández Francisco Bevia Pérez Marco Antonio Piscil Salazar Daniel Ortiz De La Peña Salazar Ilarregui Francisco Javier Sánchez González Amilcar Espinoza Aguilar 《Endocrinología y nutrición》2010,57(10):460-466
Background99mTc sestamibi scanning and aspiration biopsy can predict the histopathological result of a thyroid nodule fairly accurately.ObjectiveTo determine the accuracy of 99mTc sestamibi scanning in detecting malignancy in patients with thyroid nodule confirmed by definitive histopathological report after thyroidectomy.Material and methodsA total of 69 patients with a solitary thyroid nodule were studied. In all patients, fine needle aspiration, total thyroidectomy for suspected thyroid cancer, and histological analysis of the surgical specimen were performed. There were 54 patients with a positive 99mTc sestamibi scan; of these, malignancy was confirmed by histological analysis in 25 and excluded in 29. There were 15 patients with a negative 99mTc sestamibi scan; of these, three had a final diagnosis of cancer and 12 were confirmed as cancer-free.ResultsThe diagnostic accuracy of 99mTc sestamibi scanning in detecting malignancy in thyroid nodules was determined through a statistical analysis. 99mTc sestamibi scan for thyroid cancer had a sensitivity of 89.28% and a specificity of 29.25%. The positive predictive value was 46.29% and the negative predictive value was 80%.ConclusionsWe believe that 99mTc sestamibi scan should be routinely used in all patients with a thyroid nodule and an indeterminate result on fine needle aspiration. This procedure is most useful in excluding malignancy in patients with a negative 99mTc sestamibi scan. 相似文献
988.
Chakri K Touati L Alfarhan AH Al-Rasheid KA Samraoui B 《Comptes rendus biologies》2010,333(11-12):836-840
The history of selection of Daphnia magna populations living in North African temporary ponds may differ from populations inhabiting permanent ponds. Laboratory experiments were conducted to examine the effect of fish Gambusia holbrooki and invertebrate Notonecta glauca kairomones on the life history traits of the freshwater Cladocera Daphnia magna Straus. With fish kairomones, Daphnia reproduced early and had a significantly smaller size at first reproduction (SFR) and a smaller size of neonates compared to control. In contrast, daphnids reared in water treated with Notonecta glauca had no effect on the age at first reproduction but females were also smaller and produced smaller neonates. 相似文献
989.
Rossini M Maddali Bongi S La Montagna G Minisola G Malavolta N Bernini L Cacace E Sinigaglia L Di Munno O Adami S 《Arthritis research & therapy》2010,12(6):R216
Introduction
The aim of this study was to estimate the prevalence and determinants of vitamin D deficiency in patients with rheumatoid arthritis (RA) as compared to healthy controls and to analyze the association between 25-hydroxyvitamin D (25(OH)D) with disease activity and disability. 相似文献990.
Carlo A. Rossi Michela Pozzobon Andrea Ditadi Karolina Archacka Annalisa Gastaldello Marta Sanna Chiara Franzin Alberto Malerba Gabriella Milan Mara Cananzi Stefano Schiaffino Michelangelo Campanella Roberto Vettor Paolo De Coppi 《PloS one》2010,5(1)
Satellite cells (SCs) represent a distinct lineage of myogenic progenitors responsible for the postnatal growth, repair and maintenance of skeletal muscle. Distinguished on the basis of their unique position in mature skeletal muscle, SCs were considered unipotent stem cells with the ability of generating a unique specialized phenotype. Subsequently, it was demonstrated in mice that opposite differentiation towards osteogenic and adipogenic pathways was also possible. Even though the pool of SCs is accepted as the major, and possibly the only, source of myonuclei in postnatal muscle, it is likely that SCs are not all multipotent stem cells and evidences for diversities within the myogenic compartment have been described both in vitro and in vivo. Here, by isolating single fibers from rat flexor digitorum brevis (FDB) muscle we were able to identify and clonally characterize two main subpopulations of SCs: the low proliferative clones (LPC) present in major proportion (∼75%) and the high proliferative clones (HPC), present instead in minor amount (∼25%). LPC spontaneously generate myotubes whilst HPC differentiate into adipocytes even though they may skip the adipogenic program if co-cultured with LPC. LPC and HPC differ also for mitochondrial membrane potential (ΔΨm), ATP balance and Reactive Oxygen Species (ROS) generation underlying diversities in metabolism that precede differentiation. Notably, SCs heterogeneity is retained in vivo. SCs may therefore be comprised of two distinct, though not irreversibly committed, populations of cells distinguishable for prominent differences in basal biological features such as proliferation, metabolism and differentiation. By these means, novel insights on SCs heterogeneity are provided and evidences for biological readouts potentially relevant for diagnostic purposes described. 相似文献