Search results for " (OCT)"

Stable heavy pentaquarks in constituent models

2017

It is shown that standard constituent quark models produce $(\bar c c qqq)$ hidden-charm pentaquarks, where $c$ denotes the charmed quark and $q$ a light quark, which lie below the lowest threshold for spontaneous dissociation and thus are stable in the limit where the internal $\bar c c$ annihilation is neglected. The binding is a cooperative effect of the chromoelectric and chromomagnetic components of the interaction, and it disappears in the static limit with a pure chromoelectric potential. Their wave function contains color sextet and color octet configurations for the subsystems and can hardly be reduced to a molecular state made of two interacting hadrons. These pentaquark states co…

Yeast contains multiple forms of histone acetyltransferase.

1989

We have assayed several methods to quantitatively recover yeast histone acetyltransferases in an attempt to study the multiplicity of enzymatic activities. Two methods, namely (NH4)2SO4 precipitation and salt dissociation of chromatin in 0.5 M NaCl, yielded convenient preparations of total histone acetyltransferases. DEAE-Sepharose chromatography of the crude extracts resulted in the separation of three peaks of activity when total yeast histones were used as substrate. However, the scanning of the enzymatic activity toward individual histones along the chromatography, achieved by determining the specific activity of the individual histones after incubating whole histones and [14C]acetyl-Co…

Site specificity of pea histone acetyltransferase B in vitro.

1993

Histone acetyltransferase B from pea embryonic axes has been purified approximately 300-fold by a combination of chromatographic procedures, including affinity chromatography on histone-agarose. The enzyme preparation has been used for the in vitro transfer of acetyl groups from [1-14C]acetyl-CoA to non-acetylated pea histone H4. Up to three acetyl groups can be introduced into the histone. The resulting mono-, di-, and triacetylated H4 isoforms were separated and sequenced to determine the acetylated sites. Only sites 5, 12, and 16 were used by histone acetyltransferase B, but no clear preference among them was observed. The absence of modification of other potentially acetylatable sites i…

HAT1 and HAT2 Proteins Are Components of a Yeast Nuclear Histone Acetyltransferase Enzyme Specific for Free Histone H4

1998

We have analyzed the histone acetyltransferase enzymes obtained from a series of yeast hat1, hat2, and gcn5 single mutants and hat1,hat2 and hat1,gcn5 double mutants. Extracts prepared from both hat1 and hat2 mutant strains specifically lack the following two histone acetyltransferase activities: the well known cytoplasmic type B enzyme and a free histone H4-specific histone acetyltransferase located in the nucleus. The catalytic subunits of both cytoplasmic and nuclear enzymes have identical molecular masses (42 kDa), the same as that of HAT1. However, the cytoplasmic complex has a molecular mass (150 kDa) greater than that of the nuclear complex (110 kDa). The possible functions of HAT1 a…

Bromodomain factor 1 (Bdf1) protein interacts with histones

2001

AbstractUsing a yeast two-hybrid assay we detected an interaction between the N-terminal region of histone H4 (amino acids 1–59) and a fragment of the bromodomain factor 1 protein (Bdf1p) (amino acids 304–571) that includes one of the two bromodomains of this protein. No interaction was observed using fragments of histone H4 sequence smaller than the first 59 amino acids. Recombinant Bdf1p (rBdf1p) demonstrates binding affinity for histones H4 and H3 but not H2A and H2B in vitro. Moreover, rBdf1p is able to bind histones H3 and H4 having different degrees of acetylation. Finally, we have not detected histone acetyltransferase activity associated with Bdf1p.

Unveiling novel interactions of histone chaperone Asf1 linked to TREX-2 factors Sus1 and Thp1

2014

13 páginas, 7 figuras, 2 yablas

Hif1 Is a Component of Yeast Histone Acetyltransferase B, a Complex Mainly Localized in the Nucleus

2004

Hat1 is the catalytic subunit of the only type B histone acetyltransferase known (HAT-B). The enzyme specifically acetylates lysine 12, and to a lesser extent lysine 5, of free, non-chromatin-bound histone H4. The complex is usually isolated with cytosolic fractions and is thought to be involved in chromatin assembly. The Saccharomyces cerevisiae HAT-B complex also contains Hat2, a protein stimulating Hat1 catalytic activity. We have now identified by two-hybrid experiments Hif1 as both a Hat1- and a histone H4-interacting protein. These interactions were dependent on HAT2, indicating a mediating role for Hat2. Biochemical fractionation and co-immunoprecipitation assays demonstrated that Hi…

R E L A Z I O N I T R A I N D I C E  D I R E S I S T E N Z A I N T R A PA R E N C H I M A L E R E N A L E E D E N S I TA’ VA S C O L A R E R E T I N …

2022

Modificazioni dell’emodinamica splancnica dopo somministrazione endovenosa di terlipressina in associazione ad infusione di octreotide nel suino.

2014

L’obiettivo di questo studio è valutare gli effetti sull’emodinamica splancnica dopo la somministrazione di terlipressina in associazione all’infusione endovenosa di octeotride. La terlipressina trova impiego clinico nella terapia selettiva delle emorragie da varici esofagee, principale complicanza dell’ipertensione portale, senza provocare alterazioni della dinamica emocoagulativa. L’uso dell’octreotide è ben conosciuto come valida terapia per emorragia delle varici in pazienti cirrotici attraverso la riduzione della pressione portale e il flusso sanguigno portocollaterale. Lo scopo del presente studio è valutare gli effetti dell’associazione farmacologica di terlipressina e octreotide nel…

OCT e GDx VCC : nella diagnosi e nel follow-up

2009

Considerando che è sempre meglio prevenire che curare, l'autore evidenzia l'importanza dell'OCT e del GDx VCC rispetto alla perimetria computerizzata .Il danno del Campo Visivo, infatti, nella perimetria computerizzata non è mai precoce, pertanto, il difetto della funzione visiva si rileva quando è presente già un danno avanzato anatomico. l'OCT e il GDx VCC mediante il software permettono,invece, l'analisi dell'RNFL che precedono di almeno 5 anni le alterazioni perimetriche.