PubMed Health⌕ Search

Biomedical subjects

A Clemente

Publications and source records attributed to A Clemente.

At least 19 recordsLinked to original sources
PubMed2005

Use of levobupivacaine for the treatment of postoperative pain after thoracotomies.

Continuous thoracic epidural analgesia with an opiod-local anaesthetic mixture is the most appropriate strategy to control postoperative pain in thoracic surgery. Levobupivacaine, the pure S(-) enantiomer of racemic bupivacaine, has less cardiotoxic and neurotoxic potential but similar anaesthetic properties of its native agent. There are no studies in thoracic surgery that had established the minimal efficient concentration of this anaesthetic when used with an epidural opioid. The advantages of administering opioids in addition to local anaesthetics in the epidural space are the possibility to decrease dose and consequently side-effects of each drug and to exploit the documented synergy between these different categories of drugs in producing segmental epidural analgesia. In our departmental study (unpublished data), 2 different concentration of levobupivacaine (Group A: 0.125% and Group B: 0.0625%) combined with sufentanil (1 mg/mL) were administered in continuous epidural post-thoracotomy infusion to investigate quality of analgesia, motor block and side-effects. An intravenous PCA system has been used in the postoperative period to evaluate rescue morphine consumption. Preliminary results showed that patients of each group reported similar VAS at rest although a better pain control during cough resulted in group A. Patients receiving levobupivacaine at 0.125% presented low incidence of nausea, vomiting and pruritus probably because of the smaller amount of rescue morphine administered. At the concentration of 0.125% epidural levobupivacaine in combination with sufentanil allowed to obtain a good pain control with no adverse effects and motor block at all.

Analgesia, Epidural↗
PubMed2004

Auditory evoked potentials.

Auditory evoked potentials (AEPs) are an electrical manifestation of the brain response to an auditory stimulus. Mid-latency auditory evoked potentials (MLAEPs) and the coherent frequency of the AEP are the most promising for monitoring depth of anaesthesia. MLAEPs show graded changes with increasing anaesthetic concentration over the clinical concentration range. The latencies of Pa and Nb lengthen and their amplitudes reduce. These changes in features of waveform are similar with both inhaled and intravenous anaesthetics. Changes in latency of Pa and Nb waves are highly correlated to a transition from awake to loss of consciousness. MLAEPs recording may also provide information about cerebral processing of the auditory input, probably because it reflects activity in the temporal lobe/primary cortex, sites involved in sounds elaboration and in a complex mechanism of implicit (non declarative) memory processing. The coherent frequency has found to be disrupted by the anaesthetics as well as to be implicated in attentional mechanism. These results support the concept that the AEPs reflects the balance between the arousal effects of surgical stimulation and the depressant effects of anaesthetics. However, AEPs aren't a perfect measure of anaesthesia depth. They can't predict patients movements during surgery and the signal may be affected by muscle artefacts, diathermy and other electrical operating theatre interferences. In conclusion, once reliability of the AEPs recording became proved and the signal acquisition improved it is likely to became a routine feature of clinical anaesthetic practice.

Anesthesia↗
PubMed2003

Burkholderia genome analysis reveals new enzymes belonging to the nitrilase superfamily. The amidase of Burkholderia cepacia (hospital isolate).

Burkholderia cepacia (formerly Pseudomonas cepacia) grows in media containing acetamide or propionamide as C and N sources. Chromosomal DNA from a hospital isolate of B. cepacia served as a template in PCRs using primers designed for the amplification of the P. aeruginosa amiE gene that encodes an aliphatic amidase. Partial sequencing of the PCR products gave a translated sequence 100% identical with the amino acid sequence of P. aeruginosa amidase. A search of Burkholderia genomes detected a putative amidase in B. cepacia J2315 with high identity to the P. aeruginosa amidase and predicted that other Burkholderia species also possessed CN_hydrolases that use the same catalytic triad (Glu-Lys-Cys) as amidase. Superimposition of theoretical three-dimensional models suggested that differences in the amino acid sequences between amidases from B. cepacia (hospital isolate) and B. cepacia J2315 do not affect their three-dimensional structure.

Amidohydrolases↗
PubMed2001

Production and characterization of a mouse monoclonal antibody against the Gag p26 protein of human immunodeficiency virus type 2: identification of a new antigenic epitope.

One anticapsid (p26) mouse monoclonal antibody was developed after immunization with recombinant p26 Gag protein and was tested for reactivity with different HIV-1 and HIV-2 isolates by ELISA and Western blot analysis. This antibody, named R26.1, reacted with all HIV-2 isolates tested and with recombinant p26 proteins, but no HIV-1 isolates. The epitope of antibody R26.1 was mapped to residues 50-71 in the N-terminal domain of the capsid protein, a highly conserved region in all HIV-2 isolates sequenced to date. This monoclonal antibody may be useful for the detection of HIV-2, and for the discrimination between HIV-1 and HIV-2 infections. Likewise, the identified epitope may be useful for the detection of p26 antibodies in HIV-2-infected individuals.

Amino Acid Sequence↗
PubMed2001

Primary structure deduction and molecular modelling from a cDNA of a cellobiohydrolase-like protein from the white-rot fungus Coriolus versicolor.

Molecular cloning and cDNA sequencing analysis were used to elucidate the primary structure of a cellulase-like structure from the white-rot fungus Coriolus versicolor. The cDNA of interest was isolated from a cDNA library obtained from C. versicolor mycelia grown on cellulase inducer medium. A pattern search showed that this cellulase belongs to the glycosyl hydrolases family 6. From the deduced amino acid sequence, models of the binding and catalytic domains were built by homology modelling. The constructed models present a typical cellulose-binding domain at the N-terminal region, a rich Pro, Ser, Thr linker peptide, and a catalytic domain at the C-terminus region.

Amino Acid Sequence↗
PubMed2001

A single blind comparison of amisulpride, fluoxetine and clomipramine in the treatment of restricting anorectics.

1. The study evaluated the efficacy of amisulpride, fluoxetine and clomipramine at the beginning of the re-feeding phase of the treatment of restricting anorexia nervosa according to DSM-IV criteria. 2. 13 patients, mean weight 37.61 kg +/- 9.80 SD, were treated with clomipramine at a mean dosage of 57.69 mg +/- 25.79 SD; 10 patients, mean weight 40.90 kg +/- 6.98 SD, were treated with fluoxetine at a mean dosage of 28.00 mg +/- 10.32 SD; 12 patients, mean weight 38.41 kg +/- 8.33 SD, were treated with amisulpride at a mean dosage of 50.00 mg +/- 0.00 SD. 3. Clinical evaluation was carried out under single-blind condition at basal time and after three months by a structured clinical interview, the Eating Disorder Interview based on Long Interval Follow-up Evaluation (LIFE II BEI). 4. Patients treated with amisulpride showed a more significant increase (p=0.016) of mean weight. Concerning weight phobia, body image disturbance and amenorrhoea, no significant difference resulted.

Adult↗
PubMed2001

Alcalase rapeseed inhibitors: purification and partial characterization.

Extensive rapeseed protein hydrolysate obtained sequentially with Alcalase and Flavourzyme showed inhibitory activity towards Alcalase. Inhibitory activity decreased as the hydrolytic process progressed probably by heat denaturation and/or partial protease degradation. Alcalase rapeseed inhibitors were purified by gel filtration and subsequent ion exchange chromatography. They are composed of peptides of 8.4 and 6.1 kDa linked by interchain disulphide bonds, as observed by reducing SDS-PAGE, with a native molecular weight of 18 kDa. Aminoacid composition of the inhibitors was characterized by the high proportion of methionine (4.2%) and cysteine (4.6%). Alcalase inhibitors were partially resistant to heat treatment; after heating at 70 degrees C for 45 minutes more than 50% of the original inhibitory activity remained in the purified protein but after heating at 90 degrees C for 5 minutes, inhibitory activity decreased very fast to a basal level. The possible relation of these protease inhibitors with the 2S albumin storage proteins is discussed.

Amino Acids↗
PubMed2001

A monoclonal antibody specific for Pseudomonas aeruginosa amidase.

Amidase from Pseudomonas aeruginosa was purified by anionic exchange chromatography and used to immunise female Balb/c mice. Monoclonal antibodies (MAbs) were raised by hybridoma technology using Sp2/0 myeloma cells as fusion partner. A selected IgM subclass MAb was purified from in vitro hybridoma cell line supernatant by a two-step anionic exchange chromatography. The MAb was specific for amidase from P. aeruginosa as determined by Western blotting and recognized the native and denatured forms of the enzyme.

Amidohydrolases↗
PubMed2001

Toxic epidermal necrolysis treated with intravenous high-dose immunoglobulins: our experience.

BACKGROUND: Toxic epidermal necrolysis (TEN) is a rare severe acute exfoliative drug-induced skin disorder which has recently been ascribed to alterations in the control of keratinocyte apoptosis, mediated by an interaction between the cell surface death receptor Fas and its respective ligand. A therapeutic approach with intravenous immunoglobulins (IVIG) associated with pulse methylprednisolone, based on the inhibition of Fas-mediated keratinocyte death by naturally occurring Fas-blocking antibodies included in human immunoglobulin preparations, has produced good preliminary results. OBJECTIVE: To analyse the efficacy of IVIG in the treatment of TEN. PATIENTS: Nine patients with erythematous body surface area ranging from 38 to 85% and dermo-epidermal detachment from 4 to 37% were treated. RESULTS: Eight patients were healed and 1 died of septic shock and multiple organ failure. Interruption of further epidermal detachment occurred after an average of 4.8 days from the onset of IVIG therapy. Complete wound healing occurred after an average of 12 days. Concerning complications, 3 out of 8 surviving patients had acute respiratory failure requiring mechanical ventilation and 1 acute renal failure was treated with dialysis. Late sequelae were limited to dyschromia and nail dystrophies. No hypertrophic scars were observed. CONCLUSION: IVIG therapy represents a safe and valid approach for TEN.

Adult↗
PubMed2000

Purification and characterization of broad bean lipoxygenase isoenzymes.

Two lipoxygenase isoenzymes, BBL-1 and BBL-2, were purified from broad beans. Fractionation of globulins and albumins by ionic strength was preferred to the classical water extraction system and the ammonium sulfate fractionation as initial purification steps. From the albumin fraction, BBL-1 and BBL-2 were purified 17.6 and 35. 7-fold, respectively, by conventional gel filtration and ion-exchange chromatography. The molecular weight of both BBL-1 and BBL-2 was 97 kDa with a maximal activity around pH 5.8; however, they showed a significant difference in their K(m) values for linoleic acid: 2.3 and 0.25 mM for BBL-1 and BBL-2, respectively. BBL-1 produced hydroperoxides and ketodienes while BBL-2 produced exclusively hydroperoxides.

Chromatography, DEAE-Cellulose↗
PubMed2000

Purification, cloning and autoproteolytic processing of an aspartic proteinase from Centaurea calcitrapa.

Plant aspartic proteinases (APs) have been isolated from several seed and leaf sources but the only well characterized enzymes from flowers are cardosins and cyprosins from cardoon, Cynara cardunculus L. Here we report a full-length cDNA clone encoding an AP named cenprosin from the flowers of Centaurea calcitrapa L., a thistle related to cardoon. As found for all eukaryotic APs, the deduced primary sequence consists of a signal sequence, a propart and a mature enzyme. In addition, an internal sequence region of 104 residues typical only of plant APs (a plant-specific insert) is present in the primary structure. Northern analysis revealed that the strongest expression is in fresh flowers. The enzyme is also expressed in fairly high amounts in seeds and in leaves, a feature not detected for cardoon APs. The corresponding enzyme was purified in its precursor form from fresh flowers using ammonium-sulfate precipitation followed by ion-exchange and hydrophobic-interaction chromatography. The processing of the precursor into its mature form was studied in vitro. The enzyme underwent autocatalytic processing at pH 3.0 resulting in two chains of 16 and 30 kDa. When dried flowers were used as a starting material for purification, only 16- and 30-kDa chains were obtained, suggesting that autoproteolytic activation of procenprosin in vivo occurs mainly during drying of the flowers. This may indicate a specific degradative role for the enzyme during senescence of the flowers.

Amino Acid Sequence↗
PubMed1999

Purification and partial characterization of chickpea 2S albumin.

A chickpea 2S albumin has been purified by solubilization in 60% methanol and ion-exchange chromatography. Under denaturing conditions it is composed of two peptides of 10 and 12 kDa. Native molecular mass determined by gel filtration chromatography is 20 kDa. Amino acid composition shows that it is rich in sulfur amino acids, mainly cysteine with 4.6% of the total. On the other hand, it has antinutritional characteristics of being allergenic for chickpea-sensitive individuals and inhibitory against porcine chymotrypsin with a lesser degree toward trypsin. The results of interest from a nutritional point of view are discussed.

2S Albumins, Plant↗
PubMed1999

Interaction of chickpea (Cicer arietinum L.) legumin with oxidized linoleic acid.

Chickpea legumin has been purified and incubated under oxidizing conditions with linoleic acid to investigate the influence of this acid on the structure and nutritional quality of the protein. At the end of the incubation time, >30% of the linoleic acid was oxidized. The oxidized linoleic acid was highly detrimental to legumin, and the electrophoretic pattern of the protein was completely changed after the incubation period. Nevertheless, neither polymerization nor cleavage of the protein was observed as deduced from gel filtration chromatography, suggesting that the changes observed in native electrophoresis were probably due to oxidation of legumin. The incubation of legumin with linoleic acid also produced a diminution of the contents of methionine and histidine, by 81.3 and 24.3%, respectively. Finally, in vitro protein digestibility of chickpea legumin was also seriously affected by the incubation with linoleic acid, decreasing from 84.1 to 69.2%.

Amino Acids↗
PubMed1999

Production of extensive chickpea (Cicer arietinum L.) protein hydrolysates with reduced antigenic activity.

Chickpea protein isolate was used as starting material for the production of hypoallergenic protein hydrolysates. Western blotting of the protein isolate showed that IgE in sensitized patient sera strongly bound to the basic polypeptidic chains and recognized the acidic ones of 11S globulin. During the hydrolysis process by the individual and/or sequential action of endo- and exoproteases, a high reduction of antigenic activity was observed. Results suggest that the presence of intact or partially hydrolyzed basic polypeptide chains of 11S globulin are responsible for the formation of IgE complexes in protein hydrolysates obtained by exoprotease treatment; however, the digestion of these polypeptide chains by individual action of endoprotease caused a high loss of antigenic activity. The most effective reduction of antigenicity, >90%, was observed in extensive hydrolyzed chickpea proteins obtained by sequential treatment with endo- and exopeptidases. This chickpea protein hydrolysate could be useful for the elaboration of specialized hypoallergenic food products.

Blotting, Western↗
PubMed1999

Production and characterization of a specific rubisco monoclonal antibody, and its use in rubisco quantification during Zantedeschia aethiopica spathe development.

Ribulose 1,5-bisphosphate carboxylase/oxygenase was purified from leaves of Zantedeschia aethiopica and used to immunize female Balb/c mice. Monoclonal antibodies (MAbs) were raised by hybridoma technology using Sp2/0 myeloma cells as fusion partner. A random selected IgG2a subclass MAb was purified from ascitic fluid by affinity chromatography on Protein A-Sepharose CL-4B, with a recovery of 84.3% and it was apparently homogeneous on native PAGE. The monoclonality of the purified MAb was determined by IEF. The MAb was highly specific for Rubisco from leaves of Z. aethiopica as determined by Western blotting and was used to determine the concentration of Rubisco protein by enzyme-linked immunoadsorbent assay (ELISA), at three distinct stages of Z. aethiopica spathe development and in the leaf. The results suggest de novo synthesis of Rubisco during the spathe regreening, which could explain, at least in part, the increase of photosynthetic activity observed during regreening.

Antibodies, Monoclonal↗