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91.
John R. Spence 《西北部美国博物学家》2011,45(1)
Symphyotrichum expansum (Puepp ex Spreng.) Nesom is reported new to Utah from the Escalante River drainage. A major range extension is reported for Aralia racemosa L. in the Escalante drainage, and additional populations are reported of the rare species Imperata brevifolia Vasey in Utah, including the 1st record for the Grand Staircase--Escalante National Monument. Heterotheca grandiflora Nutt. is reported new to north central Arizona. New locations and notes on an additional 22 rare species in Glen Canyon National Recreation Area are listed. 相似文献
92.
93.
This study examined the individual and simultaneous adsorption of SOx(SO2)and NOx(NO-NO2)on activated carbon prepared from waste palm shell.The adsorption process was examined in a fixed bed reactor at low temperatures(100 300°C).For individual adsorption without any catalytic activation,SOx showed good adsorption whereas NOx was very much poor.In the simultaneous adsorption of SOx and NOx,SOx showed greater adsorption affinity than NOx.For palm shell activated carbon(PSAC)impregnated with metal catalyst(Ni and Ce)the concentration adsorbed profile showed that the amount of SOx adsorbed decreased regularly,while the amount of the adsorbed NOx increased irregularly.The properties of the pure and impregnated PSAC were analyzed by BET,SEM and EDX.These investigations indicated that PSAC impregnated with metal catalyst is the determining factor in the adsorption of SOx and NOx simultaneously. 相似文献
94.
G. E. Callander R. A. D. Bathgate 《Cellular and molecular life sciences : CMLS》2010,67(14):2327-2341
Since its discovery in the 1920s, relaxin has enjoyed a reputation as a peptide hormone of pregnancy. However, relaxin and
other relaxin family peptides are now associated with numerous non-reproductive physiologies and disease states. The new millennium
bought with it the sequence of the human genome and subsequently new directions for relaxin research. In 2002, the ancestral
relaxin gene RLN3 was identified from genome databases. The relaxin-3 peptide is highly expressed in a small region of the brain and in species
from teleost to primates and has both conserved sequence and sites of expression. Combined with the discovery of the relaxin
family peptide receptors, interest in the role of the relaxin family peptides in the central nervous system has been reignited.
This review explores the relaxin family peptides that are expressed in or act upon the brain, the receptors that mediate their
actions, and what is currently known of their functions. 相似文献
95.
S Peña-Llopis S Vega-Rubín-de-Celis A Liao N Leng A Pavía-Jiménez S Wang T Yamasaki L Zhrebker S Sivanand P Spence L Kinch T Hambuch S Jain Y Lotan V Margulis AI Sagalowsky PB Summerour W Kabbani SW Wong N Grishin M Laurent XJ Xie CD Haudenschild MT Ross DR Bentley P Kapur J Brugarolas 《Nature genetics》2012,44(9):1072
96.
Hydrogels resulting from the self-assembly of small peptides are smart nanobiomaterials as their nanostructuring can be readily tuned by environmental stimuli such as pH,ionic strength and temperature,thereby favoring their practical applications.This work reports experimental observations of formation of peptide hydrogels in response to the redox environment.Ac-I 3 K-NH 2 is a short peptide amphiphile that readily self-assembles into long nanofibers and its gel formation occurs at concentrations of about 10 mmol/L.Introduction of a Cys residue into the hydrophilic region leads to a new molecule,Ac-I 3 CGK-NH 2,that enables the formation of disulfide bonds between self-assembled nanofibers,thus favoring cross-linking and promoting hydrogel formation.Under oxidative environment,Ac-I 3 CGK-NH 2 formed hydrogels at much lower concentrations(even at 0.5 mmol/L).Furthermore,the strength of the hydrogels could be easily tuned by switching between oxidative and reductive conditions and time.However,AFM,TEM,and CD measurements revealed little morphological and structural changes at molecular and nano dimensions,showing no apparent influence arising from the disulfide bond formation. 相似文献
97.
Anderson BH Kasher PR Mayer J Szynkiewicz M Jenkinson EM Bhaskar SS Urquhart JE Daly SB Dickerson JE O'Sullivan J Leibundgut EO Muter J Abdel-Salem GM Babul-Hirji R Baxter P Berger A Bonafé L Brunstom-Hernandez JE Buckard JA Chitayat D Chong WK Cordelli DM Ferreira P Fluss J Forrest EH Franzoni E Garone C Hammans SR Houge G Hughes I Jacquemont S Jeannet PY Jefferson RJ Kumar R Kutschke G Lundberg S Lourenço CM Mehta R Naidu S Nischal KK Nunes L Ounap K Philippart M Prabhakar P Risen SR 《Nature genetics》2012,44(3):338-342
Coats plus is a highly pleiotropic disorder particularly affecting the eye, brain, bone and gastrointestinal tract. Here, we show that Coats plus results from mutations in CTC1, encoding conserved telomere maintenance component 1, a member of the mammalian homolog of the yeast heterotrimeric CST telomeric capping complex. Consistent with the observation of shortened telomeres in an Arabidopsis CTC1 mutant and the phenotypic overlap of Coats plus with the telomeric maintenance disorders comprising dyskeratosis congenita, we observed shortened telomeres in three individuals with Coats plus and an increase in spontaneous γH2AX-positive cells in cell lines derived from two affected individuals. CTC1 is also a subunit of the α-accessory factor (AAF) complex, stimulating the activity of DNA polymerase-α primase, the only enzyme known to initiate DNA replication in eukaryotic cells. Thus, CTC1 may have a function in DNA metabolism that is necessary for but not specific to telomeric integrity. 相似文献
98.
Panizzi JR Becker-Heck A Castleman VH Al-Mutairi DA Liu Y Loges NT Pathak N Austin-Tse C Sheridan E Schmidts M Olbrich H Werner C Häffner K Hellman N Chodhari R Gupta A Kramer-Zucker A Olale F Burdine RD Schier AF O'Callaghan C Chung EM Reinhardt R Mitchison HM King SM Omran H Drummond IA 《Nature genetics》2012,44(6):714-719
Cilia are essential for fertilization, respiratory clearance, cerebrospinal fluid circulation and establishing laterality. Cilia motility defects cause primary ciliary dyskinesia (PCD, MIM244400), a disorder affecting 1:15,000-30,000 births. Cilia motility requires the assembly of multisubunit dynein arms that drive ciliary bending. Despite progress in understanding the genetic basis of PCD, mutations remain to be identified for several PCD-linked loci. Here we show that the zebrafish cilia paralysis mutant schmalhans (smh(tn222)) encodes the coiled-coil domain containing 103 protein (Ccdc103), a foxj1a-regulated gene product. Screening 146 unrelated PCD families identified individuals in six families with reduced outer dynein arms who carried mutations in CCDC103. Dynein arm assembly in smh mutant zebrafish was rescued by wild-type but not mutant human CCDC103. Chlamydomonas Ccdc103/Pr46b functions as a tightly bound, axoneme-associated protein. These results identify Ccdc103 as a dynein arm attachment factor that causes primary ciliary dyskinesia when mutated. 相似文献
99.
Bis JC DeCarli C Smith AV van der Lijn F Crivello F Fornage M Debette S Shulman JM Schmidt H Srikanth V Schuur M Yu L Choi SH Sigurdsson S Verhaaren BF DeStefano AL Lambert JC Jack CR Struchalin M Stankovich J Ibrahim-Verbaas CA Fleischman D Zijdenbos A den Heijer T Mazoyer B Coker LH Enzinger C Danoy P Amin N Arfanakis K van Buchem MA de Bruijn RF Beiser A Dufouil C Huang J Cavalieri M Thomson R Niessen WJ Chibnik LB Gislason GK Hofman A Pikula A Amouyel P Freeman KB Phan TG Oostra BA Stein JL 《Nature genetics》2012,44(5):545-551
Aging is associated with reductions in hippocampal volume that are accelerated by Alzheimer's disease and vascular risk factors. Our genome-wide association study (GWAS) of dementia-free persons (n = 9,232) identified 46 SNPs at four loci with P values of <4.0 × 10(-7). In two additional samples (n = 2,318), associations were replicated at 12q14 within MSRB3-WIF1 (discovery and replication; rs17178006; P = 5.3 × 10(-11)) and at 12q24 near HRK-FBXW8 (rs7294919; P = 2.9 × 10(-11)). Remaining associations included one SNP at 2q24 within DPP4 (rs6741949; P = 2.9 × 10(-7)) and nine SNPs at 9p33 within ASTN2 (rs7852872; P = 1.0 × 10(-7)); along with the chromosome 12 associations, these loci were also associated with hippocampal volume (P < 0.05) in a third younger, more heterogeneous sample (n = 7,794). The SNP in ASTN2 also showed suggestive association with decline in cognition in a largely independent sample (n = 1,563). These associations implicate genes related to apoptosis (HRK), development (WIF1), oxidative stress (MSR3B), ubiquitination (FBXW8) and neuronal migration (ASTN2), as well as enzymes targeted by new diabetes medications (DPP4), indicating new genetic influences on hippocampal size and possibly the risk of cognitive decline and dementia. 相似文献
100.
Oswaldo Hernández-Gallegos Felipe de Jesús Rodríguez-Romero Petra Sánchez-Nava Fausto R. Méndez 《西北部美国博物学家》2011,69(1)
Multiple surveys carried out by herpetologists in México, D.F., during the 1980s failed to find specimens of Aspidoscelis septemvitatta (Squamata: Teiidae). However, 10 specimens were recently collected to the east of México, D.F., inside a protected area, Sierra de Santa Catarina. The Sierra de Santa Catarina has been heavily modified by human activity and habitation. Morphological and natural history information about the specimens are presented, as well as notes on locality. 相似文献