559 research outputs found

    The primary structure of rabbit liver cytosolic serine hydroxymethyltrasferase

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    The primary structure of mitochondrial aspartate aminotrasferase from human heart

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    The complete amino acid sequence of the mitochondrial asparate aminotransferase (L-aspartate:2-oxoglutarate aminotransferase, EC 2.6.1.1) from human heart has been determined based mainly on analysis of peptides obtained by digestion with trypsin and by chemical cleavage with cyanogen bromide. Comparison of the sequence with those of the isotopic isoenzymes from pig, rat and chicken showed 27, 29 and 55 differences, respectively, out of a total of 401 amino acid residues. Evidence for structural microheterogeneity at position 317 has also been obtained

    Novel Sugar-incorporated N-heterocyclic Carbene (NHC) Gold(I) Complexes as Potential Anticancer Agents

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    New metal complexes containing anticancer drugs are one of the major interests in bioinorganic or bioorganometallic medicinal chemistry. The development of novel metallodrugs is shifting to the use of non platinum central atoms coordinating different organic ligands in order to overcome the drawbacks (e.g. resistance, side effects) of the platinum antitumor agents. [1]. Gold(I) complexes show a very promising antiproliferative effects, but they are remarkable oxidizing properties. In order to reduce this character, in the last years, several studies have been reported based on gold(I) N-heterocyclic carbenes (NHCs) in vitro and in a few cases also in vivo [2]. Within this frame we have designed new gold(I) complexes based on sugar incorporated N-heterocyclic carbene. The presence of the sugar moiety allows to tune the lipophilicity behavior of the complexes. The complexes have been synthesized according to the scheme reported below. After the preparation of the NHC ligand, in the first step the corresponding Ag-complex (1AgBr) was prepared from Ag2O, to act as starting materials for transmetalation. The reaction of 1AgBr with gold(I) precursor, THTAuCl (THT = tetrahydrothiophene), in dichloromethane at room temperature overnight afford to gold complex. The compound was identified by NMR and RX. Starting from 1Cl, the cationic gold derivatives were prepared adding phosphorous and sulphur based neutral ligands, in the presence of silver tetrafluoroborate, as a chloride abstractor. The ligands have been selected in order to modulate electronic and hydrophilic complexes properties. The compounds will be investigated in screening on human cell line

    Isolation and Characterization of Multiple Forms of Glutamate-Aspartate Aminotransferase from Pig Heart

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    Abstract At least four different protein fractions provided with aspartate aminotransferase activity can be isolated from pig heart cytoplasm. No difference is detected in the sedimentation coefficient, immunodiffusion properties, and primary structure (as studied by quantitative amino acid analysis and peptide mapping of tryptic digests) of the three main fractions, called, respectively, α, β, and γ in their order of increasing anodic mobility on starch gel electrophoresis. The three main fractions differ significantly in specific activity, kinetics of recombination of the apoenzyme with the coenzyme, and behavior in 8 m urea. The most visible difference among them is in the way in which the coenzyme is bound to the enzyme protein. In the α and β fractions, pyridoxal phosphate is bound mostly in an "active" mode, characterized by absorption peaks at 362 or 430 mµ (depending upon the pH) and by the capacity to transaminate reversibly with the amino acid substrates. In the γ form, most of the coenzyme is bound in a nonactive mode, characterized by an absorption peak at 340 mµ and by the incapacity to react with amino acid substrates. Upon aging, the α and β fractions lose some activity, while a portion of their coenzyme becomes bound in the inactive mode. Even after these changes have occurred, the various fractions maintain their electrophoretic individuality, which is also preserved after resolution and after treatment with concentrated urea. Electrophoretic analyses carried out on a water extract of a single heart taken immediately after the death of the animal reveal the presence of the various subforms; this indicates either that the various subforms exist as such in the living cell or, if they are artifacts, that they must be formed very early in the preparation and under extremely mild conditions

    The primary structure of rabbit liver mitochondrial serine hydroxymethyltransferase.

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    The complete amino acid sequence of mitochondrial serine hydroxymethyltransferase from rabbit liver was determined. The sequence was obtained from analysis of peptides isolated from chymotryptic, cyanogen bromide, and limited acid cleavages of the protein. The enzyme consists of four identical subunits, each of 475 residues, i.e. 8 residues shorter than the subunit of the corresponding cytosolic isoenzyme. The sequences of the two rabbit proteins are easily aligned, provided a gap of 5 residues near the amino terminus and a gap of 3 residues near the carboxyl terminus are included in the mitochondrial sequence. The overall degree of identity between the two isoenzymes is 61.9%, whereas the structural identity of each eukaryotic isoenzyme with the corresponding Escherichia coli enzyme is about 40%. The rabbit isoenzymes are about 70 residues longer than the E. coli enzyme, with one-half of these residues accounted for by insertions in both isoenzymes near their carboxyl terminus. Predictions of secondary structure and calculations of hydropathy profiles are also presented, suggesting an even more extensive degree of identity in the three-dimensional folding of the three proteins, in accord with the known similarity of their catalytic properties. Evidence was obtained for the existence of additional molecular forms of the mitochondrial protein, differing in the absence of some amino acid residues at the amino terminus of the polypeptide chain

    The Italian clinical experience with adalimumab in Crohn's disease: Eleven clinical cases

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    This supplement contains 11 clinical cases from 11 Italian inflammatory bowel disease (IBD) specialists, giving an overview of clinical practice with regard to the use of adalimumab in the management of Crohn’s disease (CD)

    The combined use of VIGl@ct (R) (bioMerieux) and fluorescent amplified length fragment polymorphisms in the investigation of potential outbreaks

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    Even with good surveillance programmes, hospital-acquired infections (HAls) are not always recognized and this may lead to an outbreak. In order to reduce this risk, we propose a model for prompt detection of HAls, based on the use of a real-time epidemiological information system called VIGI@ct (R) (bioMerieux, Las Balmas, France) and on the rapid confirmation or exclusion of the genetic relationship among pathogens using fluorescent amplified length fragment polymorphism (f-AFLP) microbial fingerprinting. We present the results of one year's experience with the system, which identified a total, of 306 suspicious HAls. Of these, 281 (92%) were 'confirmed' by clinical evidence, 16 (5%) were considered to be simple colonization and the tatter nine (3%) were archived as 'not answered' because of the absence of the physician's cooperation. There were seven suspected outbreaks; of these, f-AFLP analysis confirmed the clonal relationship among the isolates in four cases: outbreak 1 (four isolates of Pseudomonas aeruginosa), outbreak 2 (three Escherichia coli isolates), outbreak 6 (two Candida parapsilosis isolates) and outbreak 7 (30 ESPL-producing Klebsiella pneumoniae subsp. pneumoniae). Based on our results, we conclude that the combination of VIGI@ct (R) and f-AFLP is useful in the rapid assessment of an outbreak due to Gram-positive or Gramnegative bacteria and yeasts. (C) 2007 The Hospital Infection Society. Published by Elsevier Ltd. All rights reserved

    Mathematical model for preoperative identification of obstructed nasal subsites

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    The planning of experimental studies for evaluation of nasal airflow is particularly challenging given the difficulty in obtaining objective measurements in vivo. Although standard rhinomanometry and acoustic rhinometry are the most widely used diagnostic tools for evaluation of nasal airflow, they provide only a global measurement of nasal dynamics, without temporal or spatial details. Furthermore, the numerical simulation of nasal airflow as computational fluid dynamics technology is not validated. Unfortunately, to date, there are no available diagnostic tools to objectively evaluate the geometry of the nasal cavities and to measure nasal resistance and the degree of nasal obstruction, which is of utmost importance for surgical planning. To overcame these limitations, we developed a mathematical model based on Bernoulli's equation, which allows clinicians to obtain, with the use of a particular direct digital manometry, pressure measurements over time to identify which nasal subsite is obstructed. To the best of our knowledge, this is the first study to identify two limiting curves, one below and one above an average representative curve, describing the time dependence of the gauge pressure inside a single nostril. These upper and lower curves enclosed an area into which the airflow pattern of healthy individuals falls. In our opinion, this model may be useful to study each nasal subsite and to objectively evaluate the geometry and resistances of the nasal cavities, particularly in preoperative planning and follow-up
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