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Background: Local anaesthetics (LA) injected intraperitoneally have been found to decrease postoperative pain. This double-blind randomized study was performed comparing continuous infusion or patient-controlled intraperitoneal (i.p.) bolus injection of LA. The primary endpoint was supplemental opioid consumption during the first 24 postoperative hours., Methods: Two multi-hole catheters were placed intraperitoneally at the end of the surgery in 40 patients undergoing elective abdominal hysterectomy. The patients were randomized into two groups: Group P: patients self-injected 10 ml of levobupivacaine 1.25 mg ml(-1) via the i.p. catheter as needed, maximum once per hour, and had continuous saline infusion 10 ml h(-1) into the second catheter. Group C: patients received a continuous infusion of 10 ml h(-1) of levobupivacaine 1.25 mg ml(-1) intraperitoneally through one catheter and 10 ml saline as bolus as needed via the other. Ketobemidone was administered intravenously as rescue medication., Results: Total ketobemidone consumption during 0-24 h was lower in Group P compared with Group C (mean 23.1 vs 35.7 mg, P=0.04). No differences in the median pain scores were found between the groups. Earlier return of gastrointestinal (GI) function was found in Group P vs Group C (mean 1.5 vs 2.2 days, P<0.01), which also resulted in earlier home-readiness (mean 1.9 vs 2.7 days, P=0.04)., Conclusions: A statistically significant opioid-sparing effect was found when patient-controlled levobupivacaine was administered intraperitoneally as needed compared with continuous infusion. This was associated with a faster return of GI function and home-readiness. There was, however, a wide confidence interval in the primary endpoint, opioid consumption.

Background: Epidural anaesthesia and analgesia has been shown to suppress the neuro-hormonal stress response, but its role in the inflammatory response is unclear. The primary aim was to assess whether the choice of analgesic technique influences these processes in patients undergoing radical retropubic prostatectomy., Methods: Twenty-six patients were randomized to Group P (systemic opioid-based analgesia) or Group E (thoracic epidural-based analgesia) perioperatively. Induction and maintenance of anaesthesia followed a standardized protocol. The following measurements were made perioperatively: plasma cortisol, glucose, insulin, C-reactive proteins, leucocyte count, plasma cytokines [interleukin (IL)-6, tumour necrosis factor (TNF)-α], and pokeweed mitogen-stimulated cytokines [interferon (IFN)-γ, IL-2, IL-12p70, IL-10, IL-4, and IL-17]. Other parameters recorded were pain, morphine consumption, and perioperative complications., Results: Plasma concentration of cortisol and glucose were significantly higher in Group P compared with Group E at the end of surgery, the mean difference was 232 nmol litre(-1) [95% confidence interval (CI) 84-381] (P=0.004) and 1.6 mmol litre(-1) (95% CI 0.6-2.5) (P=0.003), respectively. No significant differences were seen in IL-6 and TNF-α at 24 h (P=0.953 and 0.368, respectively) and at 72 h (P=0.931 and 0.691, respectively). IL-17 was higher in Group P compared with Group E, both at 24 h (P=0.001) and 72 h (P=0.018) after operation. Pain intensity was significantly greater in Group P compared with Group E (P<0.05) up to 24 h., Conclusions: In this small prospective randomized study, thoracic epidural analgesia reduced the early postoperative stress response but not the acute inflammatory response after radical retrobupic prostatectomy, suggesting that other pathways are involved during the acute phase reaction.

Background: Postoperative pain after radical retropubic prostatectomy is moderate to severe. The primary aim of this study was to assess whether intra-abdominal local anaesthetics provide similar analgesia compared with thoracic epidural analgesia (TEA)., Methods: Fifty patients, ASA I-II, participated in this prospective, double-blinded study. All patients had TEA. After operation, they were randomized into two groups of 25 patients: Group PCLA (patient-controlled local analgesia): self-administration of 10 ml of ropivacaine 2 mg ml⁻¹ via the intra-abdominal catheter for 48 h. Group TEA: infusion of 10 ml h⁻¹ of ropivacaine 1 mg ml⁻¹, fentanyl 2 μg ml⁻¹, and epinephrine 2 μg ml⁻¹ epidurally for 48 h. The primary endpoint was pain on coughing at 4 h after operation. Rescue medication was morphine i.v. as required., Results: Pain on coughing at 4, 24, and 48 h was significantly lower in Group TEA [0 (0-10)] compared with Group PCLA [4 (0-10)] (P<0.05). Significantly lower pain intensity was also found in Group TEA compared with Group PCLA at the incision site, deep pain, and pain on coughing at 4 and 24 h (P<0.05). Morphine consumption was significantly greater in Group PCLA [12 (0-46)] compared with Group TEA [0 (0-20)] at 0-48 h after operation [median (range)] (P=0.015). Maximum expiratory pressure was higher in Group TEA compared with Group PCLA at 24 h (P<0.01)., Conclusions: TEA provides superior postoperative pain relief with better preservation of expiratory muscle strength compared with PCLA.

Background: Postoperative pain after radical retropubic prostatectomy can be severe unless adequately treated. Low thoracic epidural analgesia and patient-controlled intravenous analgesia were compared in this double-blind, randomized study., Methods: Sixty patients were randomly assigned to receive either low thoracic epidural analgesia (group E) or patient-controlled intravenous analgesia (group P) for postoperative pain relief. All patients had general anesthesia combined with thoracic epidural analgesia during the operation. Postoperatively, patients in group E received an infusion of 1 mg/ml ropivacaine, 2 microg/ml fentanyl, and 2 microg/ml adrenaline, 10 ml/h during 48 h epidurally, and a placebo patient-controlled intravenous analgesia pump intravenously. Patients in group P received a patient-controlled intravenous analgesia pump with morphine intravenously and 10 ml/h placebo epidurally. Pain, the primary outcome variable, was measured using the numeric rating scale at rest (incision pain and "deep" visceral pain) and on coughing. Secondary outcome variables included gastrointestinal function, respiratory function, mobilization, and full recovery. Health-related quality of life was measured using the Short Form-36 questionnaire, and plasma concentration of fentanyl was measured in five patients to exclude a systemic effect of fentanyl., Results: Incisional pain and pain on coughing were lower in group E compared with group P at 2-24 h, as was deep pain between 3 and 24 h postoperatively (P < 0.05). Maximum expiratory pressure was greater in group E at 4 and 24 h (P < 0.05) compared with group P. No difference in time to home discharge was found between the groups. The mean plasma fentanyl concentration varied from 0.2 to 0.3 ng/ml during 0-48 h postoperatively. At 1 month, the scores on emotional role, physical functioning, and general health of the Short Form-36 were higher in group E compared with group P. However, no group x time interaction was found in the Short Form-36., Conclusions: The authors found evidence for better pain relief and improved expiratory muscle function in patients receiving low thoracic epidural analgesia compared with patient-controlled analgesia for radical retropubic prostatectomy. Low thoracic epidural analgesia can be recommended as a good method for postoperative analgesia after abdominal surgery.

Aim: In this study we describe the results of adoption of local guidelines for conscious sedation (CS) during endoscopic-retrograde-cholangiopancreatography (ERCP) in Belluno Hospital. Local guidelines were created referring to SIED-SIAARTI-ANOTE guidelines for CS in gastrointestinal endoscopy., Methods: Between January 2002 and February 2004, 300 ERCPs to be performed under CS have been scheduled. According to local guidelines CS was performed by the gastroenterologist assisted by an anesthesia nurse. An anesthesiologist was always on call in the intensive care unit (ICU) for emergencies and could be on the site in less than 5 min., Results: In 278 patients the procedure was performed safely and effectively by the gastroenterologist without any anesthesiological assistance. At follow-up controls patients had either positive or no recollection of the procedure. An anesthesiologist was called in 13 cases to perform deep sedation and in 9 cases to deal with undesired effects (arterial hypertension in 5 patients, 1 episode of bradycardia, 1 of ventricular tachycardia, 1 of atrial fibrillation and 1 of hypoxia)., Conclusion: In our experience, CS during ERCP can be safely performed autonomously by a gastroenterologist in the majority of cases. Drug prescription protocol and the presence of an anesthesia nurse create ideal conditions for the operator, patient comfort and good results with a low incidence of undesired events and few calls for the anesthesiologist. To allow safe and effective performance of CS, the Department of Anesthesia should promote the in-service training and up dating of gastroenterologists and anesthesia nurses.

Headpiece (HP) is a 76-residue F-actin-binding module at the C terminus of many cytoskeletal proteins. Its 35-residue C-terminal subdomain is one of the smallest known motifs capable of autonomously adopting a stable, folded structure in the absence of any disulfide bridges, metal ligands, or unnatural amino acids. We report the three-dimensional solution structures of the C-terminal headpiece subdomains of human villin (HVcHP) and human advillin (HAcHP), determined by two-dimensional 1H-NMR. They represent the second and third structures of such C-terminal headpiece subdomains to be elucidated so far. A comparison with the structure of the chicken villin C-terminal subdomain reveals a high structural conservation. Both C-terminal subdomains bind specifically to F-actin. Mutagenesis is used to demonstrate the involvement of Trp 64 in the F-actin-binding surface. The latter residue is part of a conserved structural feature, in which the surface-exposed indole ring is stacked on the proline and lysine side chain embedded in a PXWK sequence motif. On the basis of the structural and mutational data concerning Trp 64 reported here, the results of a cysteine-scanning mutagenesis study of full headpiece, and a phage display mutational study of the 69-74 fragment, we propose a modification of the model, elaborated by Vardar and coworkers, for the binding of headpiece to F-actin.

A series of peptidosteroid derivatives containing two independent peptide chains in which Ser and His are incorporated were synthesized by solid-phase peptide synthesis. The activity of the different compounds in the hydrolysis of the activated substrate NF31 was assessed in a stepwise fashion. First, the different resin-bound derivatives 6a-l and 6x-z were individually assayed for serine esterification in the absence of water. The use of a colored substrate allowed for a visual identification of the most active compounds. Through the inclusion of control substances, the involvement of histidine in the mechanism for serine acylation was shown. Second, the hydrolysis and methanolysis of the different acylated derivatives 8a-l and 8x were evaluated using UV spectroscopy, again indicating the involvement of histidine. The feasibility of applying the above procedures in a combinatorial context was proven via the screening of artificial libraries, created by mixing the different resin-bound peptidosteroid compounds. In this respect, the use of a photocleavable linker allowed for the unambiguous structural characterization of the selected members via application of single-bead electrospray tandem mass spectrometry.

Rs-AFPs are antifungal proteins, isolated from radish (Raphanus sativus) seed or leaves, which consist of 50 or 51 amino acids and belong to the plant defensin family of proteins. Four highly homologous Rs-AFPs have been isolated (Rs-AFP1-4). The structure of Rs-AFP1 consists of three beta-strands and an alpha-helix, and is stabilized by four cystine bridges. Small peptides deduced from the native sequence, still having biological activity, are not only important tools to study structure-function relationships, but may also constitute a commercially interesting target. In an earlier study, we showed that the antifungal activity of Rs-AFP2 is concentrated mainly in the beta2-beta3 loop. In this study, we synthesized linear 19-mer peptides, spanning the entire beta2-beta3 loop, that were found to be almost as potent as Rs-AFP2. Cysteines, highly conserved in the native protein, are essential for maintaining the secondary structure of the protein. Surprisingly, in the 19-mer loop peptides, cysteines can be replaced by alpha-aminobutyric acid, which even improves the antifungal potency of the peptides. Analogous cyclic 19-mer peptides, forced to adopt a hairpin structure by the introduction of one or two non-native disulfide bridges, were also found to possess high antifungal activity. The synthetic 19-mer peptides, like Rs-AFP2 itself, cause increased Ca2+ influx in pregerminated fungal hyphae.

Based on experimental NMR data, a model was generated for the conformation of the disulfide-bond-closed cyclic peptide corresponding to the whole V3 loop of the consensus HIV-1 strain in a 20% trifluoroethanol/water solution. The obtained family of structures shows a prominent and well-defined amphipathic alpha helix at the C-terminal end of the peptide from Thr23 to Gln32. A series of turns characterizes the central Gly15-Tyr21 region, while the N-terminal region is poorly defined. Independent experimental data confirms the features of this model, and suggests that this type of conformation can be readily adopted when the V3 loop is in contact with a membrane. The examined V3 loop belongs to a macrophage tropic strain, and using the model, a structural explanation is proposed for the different requirements of V3 loops belonging to macrophage and T-cell line tropic HIV-1 strains.

Sites polluted with 2,4,6-trinitrotoluene (TNT) constitute a worldwide problem. In this work, chemical reactions for binding TNT to amino-compounds are proposed as an initial step for developing new remediation techniques to clean-up groundwater and soils contaminated with TNT. Indeed, addition of aniline and an amino acid-like cysteine caused a decrease in free TNT of 86% and 68-100%, respectively. Using 13C-NMR spectroscopy, it was shown that TNT chemically forms a Meisenheimer complex with cysteine and aniline in 1/1 (by vol.) H2O/d6-acetone.

Aesculus hippocastanum antimicrobial protein 1 (Ah-AMP1) is a plant defensin isolated from horse chestnuts. The plant defensins have been divided in several subfamilies according to their amino acid sequence homology. Ah-AMP1, belonging to subfamily A2, inhibits growth of a broad range of fungi. So far, a three-dimensional structure has been determined only for members of subfamilies A3 and B2. In order to understand activity and specificity of these plant defensins, the structure of a protein belonging to subfamily A2 is needed. We report the three-dimensional solution structure of Ah-AMP1 as determined from two-dimensional 1H nuclear magnetic resonance data. The structure features all the characteristics of the "cysteine-stabilized alpha beta-motif." A comparison of the structure, the electrostatic potential surface and regions important for interaction with the fungal receptor, is made with Rs-AFP1 (plant defensin of subfamily A3). Thus, residues important for activity and specificity have been assigned.

Raphanus sativus Antifungal Protein 1 (Rs-AFP1) is a 51 amino acid residue plant defensin isolated from radish (Raphanus sativus L.) seeds. The three-dimensional structure in aqueous solution has been determined from two-dimensional 1H NMR data recorded at 500 MHz using the DIANA/REDAC calculation protocols. Experimental constraints consisted of 787 interproton distances extracted from NOE cross-peaks, 89 torsional constraints from 106 vicinal interproton coupling constants and 32 stereospecific assignments of prochiral protons. Further refinement by simulated annealing resulted in a set of 20 structures having pairwise root-mean-square differences of 1.35(+/- 0.35) A over the backbone heavy atoms and 2.11(+/- 0.46) A over all heavy atoms. The molecule adopts a compact globular fold comprising an alpha-helix from Asn18 till Leu28 and a triple-stranded beta-sheet (beta 1 = Lys2-Arg6, beta 2 = His33-Tyr38 and beta 3 = His43-Pro50). The central strand of this beta-sheet is connected by two disulfide bridges (Cys21-Cys45 and Cys25-Cys47) to the alpha-helix. The connection between beta-strand 2 and 3 is formed by a type VIa beta-turn. Even the loop (Pro7 to Asn17) between beta-strand 1 and the alpha-helix is relatively well defined. The structure of Raphanus sativus Antifungal Protein 1 features all the characteristics of the "cysteine stabilized alpha beta motif". A comparison of the complete structure and of the regions important for interaction with the fungal receptor according to a mutational study, is made with the structure of gamma-thionin, a plant defensin that has no antifungal activity. It is concluded that this interaction is both electrostatic and specific, and some possible scenarios for the mode of action are given.

Mutational analysis of Rs-AFP2, a radish antifungal peptide belonging to a family of peptides referred to as plant defensins, was performed using polymerase chain reaction-based site-directed mutagenesis and yeast as a system for heterologous expression. The strategy followed to select candidate amino acid residues for substitution was based on sequence comparison of Rs-AFP2 with other plant defensins exhibiting differential antifungal properties. Several mutations giving rise to peptide variants with reduced antifungal activity against Fusarium culmorum were identified. In parallel, an attempt was made to construct variants with enhanced antifungal activity by substituting single amino acids by arginine. Two arginine substitution variants were found to be more active than wild-type Rs-AFP2 in media with high ionic strength. Our data suggest that Rs-AFP2 possesses two adjacent sites that appear to be important for antifungal activity, namely the region around the type VI beta-turn connecting beta-strands 2 and 3, on the one hand, and the region formed by residues on the loop connecting beta-strand 1 and the alpha-helix and contiguous residues on the alpha-helix and beta-strand 3, on the other hand. When added to F. culmorum in a high ionic strength medium, Rs-AFP2 stimulated Ca2+ uptake by up to 20-fold. An arginine substitution variant with enhanced antifungal activity caused increased Ca2+ uptake by up to 50-fold, whereas a variant that was virtually devoid of antifungal activity did not stimulate Ca2+ uptake.

Plant defensins are a class of cysteine-rich peptides of which several members have been shown to be potent inhibitors of fungal growth. A series of overlapping 15-mer peptides based on the amino acid sequence of the radish antifungal protein Rs-AFP2 have been synthesized. Peptides 6, 7, 8 and 9, comprising the region from cysteine 27 to cysteine 47 of Rs-AFP2 showed substantial antifungal activity against several fungal species (minimal inhibitory concentrations of 30-60 micrograms/mL), but no activity towards bacteria (except peptide 6 at 100 micrograms/mL). The active peptides were shown to be sensitive to the presence of cations in the medium and to the composition and pH of the medium. When present at a subinhibitory concentration (20 micrograms/mL), peptides 1, 7, 8 and 10 potentiated the activity of Rs-AFP2 from 2.3-fold to 2.8-fold. By mapping the characteristics of the active peptide on the structure of Rs-AFP2 as determined by nuclear magnetic resonance, the active region of the antifungal protein appears to involve beta-strands 2 and 3 in combination with the loop connecting those strands. A cyclized synthetic mimic of the loop, cysteine 36 to cysteine 45, was shown to have antifungal activity. Substitution of tyrosine 38 by alanine in the cyclic peptide substantially reduced the antifungal activity, indicating the importance of this residue for the activity of Rs-AFP2 as demonstrated carrier by mutational analysis.

The disulfide-bridge-closed cyclic peptide corresponding to the whole V3 loop of the RF HIV-1 strain was examined by proton two-dimensional NMR spectroscopy in water and water/trifluoroethanol solutions. Although most of the peptide is conformationally averaged in water, the NOE data support a beta-turn conformation for the central conservative GPGR region and the presence of nascent helix. Upon addition of trifluoroethanol, helix formation in the C-terminal part becomes apparent. This is confirmed by CD data. NOEs indicative of multiple and transient beta-turns around the Asn6 glycosylation site and NOEs fitting X-ray data on a linear V3 peptide-Fab complex also emerge. The C-terminal helix is shown to have amphipathic character and might thus assist in the infection process.

The disulfide bridge closed cyclic peptide corresponding to the whole Consensus V3 loop of the envelope protein gp120 of HIV-1 was examined by proton 2D-NMR spectroscopy in water and in a 20% trifluoroethanol/water solution. In water, NOE data support a beta-turn conformation for the central conservative GPGR region and point towards partial formation of a helix in the C-terminal part. Upon addition of trifluoroethanol, a C-terminal helix is formed. This is evidenced by NOE data, alpha-proton chemical shift changes and changes in the JN alpha vicinal coupling constants. The C-terminal helix is amphipathic and also occurs in other examined strains. It could therefore be an important feature for the functioning of the V3 loop.