Flavocoxid, a dual inhibitor of COX-2 and 5-LOX of natural origin, attenuates the inflammatory response and protects mice from sepsis

INTRODUCTION

Cecal ligation and puncture (CLP) is an inflammatory condition that leads to multisystemic organ failure. Flavocoxid, a dual inhibitor of cyclooxygenase (COX-2) and 5-lipoxygenase (5-LOX), has been shown in vitro to possess antiinflammatory activity in lipopolysaccharide (LPS)-stimulated rat macrophages by reducing nuclear factor (NF)-κB activity and COX-2, 5-LOX and inducible nitric oxide synthase (iNOS) expression. The aim of this study was to evaluate the effects of flavocoxid in a murine model of CLP-induced polymicrobial sepsis.

METHODS

C57BL/6J mice were subjected to CLP or sham operation. In a first set of experiments, an intraperitoneal injection of flavocoxid (20 mg/kg) or vehicle was administered 1 hour after surgery and repeated every 12 hours. Survival rate was monitored every 24 hours throughout 120 hours. Furthermore, additional groups of sham and CLP mice were killed 18 hours after surgical procedures for blood-sample collection and the lung and liver were collected for biomolecular, biochemical and histopathologic studies.

RESULTS

COX-2, 5-LOX, tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-10, extracellular-regulated-kinase 1/2 (ERK), JunN-terminal kinase (JNK), NF-κB, and β-arrestin 2 protein expression were evaluated in lung and liver with Western blot analysis. In addition, leukotriene B4 (LTB4), prostaglandin E2 (PGE2), cytokines, and lipoxin A4 serum content were measured with an enzyme-linked immunosorbent assay (ELISA). Flavocoxid administration improved survival, reduced the expression of NF-κB, COX-2, 5-LOX, TNF-α and IL-6 and increased IL-10 production. Moreover, flavocoxid inhibited the mitogen-activated protein kinases (MAPKs) pathway, preserved β-arrestin 2 expression, reduced blood LTB4, PGE2, TNF-α and IL-6, and increased IL-10 and lipoxin A4 serum levels. The treatment with flavocoxid also protected against the histologic damage induced by CLP and reduced the myeloperoxidase (MPO) activity in the lung and liver.

CONCLUSIONS

Flavocoxid protects mice from sepsis, suggesting that this dual inhibitor may represent a promising approach in such a life-threatening condition.

Intrathecal atropine to prevent postoperative nausea and vomiting after Cesarean section: a randomized, controlled trial

BACKGROUND

Postoperative nausea and vomiting (PONV) is a common adverse effect of intrathecal morphine, especially after Cesarean section. This randomized controlled trial investigated the effects of intrathecal administration of a small-dose of atropine on postoperative nausea and vomiting after Cesarean section.

METHODS

Parturients with ASA physical status class I-II scheduled for elective Cesarean section and consenting to spinal anesthesia were enrolled. They received 0.5% hyperbaric bupivacaine 12.5 mg, morphine 200 µg and one of the following three solutions: atropine 100 µg intrathecally and saline intravenously; saline intrathecally and atropine 100 µg intravenously; saline only both intravenously and intrathecally. We examined the incidence and severity of PONV, pain ratings and the need for analgesics.

RESULTS

We followed 204 parturients. The incidence of PONV was 15%, 37% and 49% in the three groups, respectively (P<0.001). The relative risk reduction for PONV when using intrathecal atropine was 69% vs. placebo and 59% vs. intravenous atropine. No differences were noted in terms of postoperative pain.

CONCLUSION

Intrathecal atropine had a significant antiemetic effect, making it a useful adjunct for intrathecal opioid-related PONV.

Continuous lumbar epidural infusion of levobupivacaine: effects of small-or large-volume regimen of infusion

BACKGROUND

The question of whether the dose, concentration or volume of a local anesthetic solution is the relevant determinant of the spread and quality of post-operative epidural analgesia is still open. In this prospective, randomized, double-blind study, we compared the effects of a large volume-low concentration with a small-volume-high-concentration lumbar epidural infusion of levobupivacaine.

METHODS

Seventy patients scheduled for total hip replacement were enrolled. After surgery, patients were randomly allocated to receive a continuous epidural infusion of levobupivacaine (10.5 mg/h) using either 0.125% levobupivacaine infused at 8.4 ml/h (low concentration group, n=35) or 0.75% levobupivacaine infused at 1.4 ml/h (high concentration group, n=35). We blindly recorded the degree of pain relief at rest and during movement every 8 h for the first two post-operative days, as well as hip flexion, motor block, rescue analgesic consumption and adverse events.

RESULTS

No difference in pain relief was observed between groups as estimated with the areas under the curve of the verbal Numerical Rating Scale for pain over time, both at rest and during movement. Similarly, there was no difference between groups in hip flexion degree, motor blockade and hemodynamic stability.

CONCLUSIONS

Continuous lumbar epidural infusion of 0.75% levobupivacaine was as effective as continuous lumbar epidural infusion of 0.125% levobupivacaine, when administered at the same hourly dose of 10.5 mg, in achieving adequate analgesia both at rest and during movement, without differences in the incidence of hypotension and motor blockade.

Activation of the cholinergic anti-inflammatory pathway reduces NF-kappab activation, blunts TNF-alpha production, and protects againts splanchic artery occlusion shock

The cholinergic anti-inflammatory pathway has not yet been studied in splanchnic artery occlusion (SAO) shock. We investigated whether electrical stimulation (STIM) of efferent vagus nerves suppresses the inflammatory cascade in SAO shock. Animals were subjected to clamping of the splanchnic arteries for 45 min, followed by reperfusion. This surgical procedure resulted in an irreversible state of shock (SAO shock). Sham-operated animals were used as controls. Two minutes before the start of reperfusion, rats were subjected to bilateral cervical vagotomy (VGX) or sham surgical procedures. Application of constant voltage pulses to the caudal vagus ends (STIM: 5 V, 2 ms, 6 Hz for 15 min, 5 min after the beginning of reperfusion) increased survival rate (VGX + SAO + Sham STIM = 0% at 4 h of reperfusion; VGX + SAO + STIM = 90% at 4 h of reperfusion), reverted the marked hypotension, inhibited IkappaBalpha liver loss, blunted the augmented nuclear factor-kappaB activity, decreased hepatic tumor necrosis factor (TNF)-alpha mRNA (VGX + SAO + Sham STIM = 1.0 +/- 1.9 TNF-alpha/glyceraldehyde-3-phosphate dehydrogenase ratio; VGX + SAO + STIM = 0.3 +/- 0.2 TNF-alpha/glyceraldehyde-3-phosphate dehydrogenase ratio), reduced plasma TNF-alpha (VGX + SAO + Sham STIM = 118 +/- 19 pg/mL; VGX + SAO + STIM = 39 +/- 8 pg/mL), ameliorated leukopenia, and decreased leukocyte accumulation, as revealed by means of myeloperoxidase activity in the ileum (VGX + SAO + Sham STIM = 7.9 +/- 1 U/g tissue; VGX + SAO + STIM = 3.1 +/- 0.7 U/g tissue) and in the lung (VGX + SAO + Sham STIM = 8.0 +/- 1.0 U/g tissue; VGX + SAO + STIM = 3.2 +/- 0.6 U/g tissue). Chlorisondamine, a nicotinic receptor antagonist, abated the effects of vagal stimulation. Our results show a parasympathetic inhibition of nuclear factor-kappaB and TNF-alpha in SAO shock.

Recombinant human erythropoietin improves angiogenesis and wound healing in experimental burn wounds*

OBJECTIVE

Erythropoietin interacts with vascular endothelial growth factor (VEGF) and stimulates endothelial cell mitosis and motility; thus it may be of importance in the complex phenomenon of wound healing. The purpose of this study was to investigate the effect of recombinant human erythropoietin (rHuEPO) on experimental burn wounds.

DESIGN

Randomized experiment.

SETTING

Research laboratory.

SUBJECTS

C57BL/6 male mice weighing 25-30 g.

INTERVENTIONS

Mice were immersed in 80 degrees C water for 10 secs to achieve a deep-dermal second degree burn. Animals were randomized to receive either rHuEPO (400 units/kg/day for 14 days in 100 microL subcutaneously) or its vehicle alone (100 microl/day distilled water for 14 days subcutaneously). On day 14 the animals were killed. Burn areas were used for histologic examination, evaluation of neoangiogenesis by immunohistochemistry, and expression (Western blot) of the specific endothelial marker CD31 as well as quantification of microvessel density, measurement of VEGF wound content (enzyme-linked immunosorbent assay), expression (Western blot) of endothelial and inducible nitric oxide synthases, and determination of wound nitric oxide (NO) products.

MEASUREMENTS AND MAIN RESULTS

rHuEPO increased burn wound reepithelialization and reduced the time to final wound closure. These effects were completely abated by a passive immunization with specific antibodies against erythropoietin. rHuEPO improved healing of burn wound through increased epithelial proliferation, maturation of the extracellular matrix, and angiogenesis. The hematopoietic factor augmented neoangiogenesis as suggested by the marked increase in microvessel density and by the robust expression of the specific endothelial marker CD31. Furthermore, rHuEPO enhanced the wound content of VEGF caused a marked expression of endothelial and inducible nitric oxide synthases and increased wound content of nitric oxide products.

CONCLUSIONS

Our study suggests that rHuEPO may be an effective therapeutic approach to improve clinical outcomes after thermal injury.

Central venous catheters and infections

The indications to the positioning of central venous catheters (CVCs) are various: parenteral nutrition, chemotherapy, infusion of large amount of fluids or blood products, chronic access for hemodialysis, invasive measurement of hemodynamic variables. Infection is the most important clinical complication associated with the use of CVC, both in terms of incidence and of gravity. Despite the efforts for the optimization of the materials that are more and more biocompatible, the presence of a foreign body in the organism is an ideal substratum for the microbial colonization. The Catheter-Related-Bloodstream-Infections (CRBI) involve a pro-longation of recovery stay, the increase in costs of hospitalization and an increase in morbidity and mortality. The infections are caused by: Staphylococcus aureus and Staphylococcus epidermidis (60%), other bacteria (Enterococ-cus faecalis and Faecium, Pseudomonas aeruginosa; 25%) and among fungi by Candida albicans and Parapsilosis (15%). In order to prevent the CRBI it's important to follow some behavioural norms, both during the positioning of the catheter and in the subsequent assistance to the patient. In case of CRBI it is fundamental to make a sure diagnosis with the positivity for the same pathogen of 2 hemocultures obtained from CVC and from a peripheral vein and then with the microbiological analysis of the tip of the catheter, in order to carry out the specific antibiotic therapy.

LIPID PEROXIDATION INHIBITION BY RAXOFELAST IMPROVES ANGIOGENESIS AND WOUND HEALING IN EXPERIMENTAL BURN WOUNDS

We investigated the effects of raxofelast, a lipid peroxidation inhibitor, in an experimental model of burn wounds. C57BL/6 male mice of 25-30 g were immersed in 80 degrees C water for 10 seconds to achieve a partial-thickness scald burn. Animals received intraperitoneally either raxofelast (20 mg/kg/day for 14 days in 100 microL) or its vehicle alone (100 microL/day for 14 days). On day 14, burn areas were used for measuring conjugated dienes, reduced glutathione levels, histological damage, neoangiogenesis by immunohistochemistry and expression (Western blot) of the specific endothelial marker CD31 as well as quantification of microvessel density, VEGF wound content, endothelial and inducible nitric oxide synthase (eNOS and iNOS) expression and wound nitrite content. Raxofelast decreased tissue conjugated dienes (vehicle 6.1 +/- 1.4 DeltaABS/mg protein; raxofelast 3.7 +/- 0.8 DeltaABS/mg protein), prevented tissue glutathione consumption (vehicle 3.2 +/- 0.9 micromol/g protein; raxofelast 6.7 +/- 1.8 mumol/g protein), increased epithelial proliferation, extracellular matrix maturation, and augmented neoangiogenesis as suggested by the marked increase in microvessel density and by the robust expression of the specific endothelial marker CD31 (vehicle 9.4 +/- 1.1 integrated intensity; raxofelast 14.8 +/- 1.8 integrated intensity). Furthermore, raxofelast enhanced VEGF wound content (vehicle 1.4 +/- 0.4 pg/mg protein; raxofelast 2.4 +/- 0.6 pg/mg protein), caused a marked expression of eNOS (vehicle 16.1 +/- 3 integrated intensity; raxofelast 26.2 +/- 4 integrated intensity) and iNOS (vehicle 9.1 +/- 1.8 integrated intensity; raxofelast 16.2 +/- 3.5 integrated intensity) and increased wound nitrite content. Lipid peroxidation inhibition by raxofelast may be an effective therapeutic approach to improve clinical outcomes after thermal injury.

Protective effects of SP600125 a new inhibitor of c-jun N-terminal kinase (JNK) and extracellular-regulated kinase (ERK1/2) in an experimental model of cerulein-induced pancreatitis

Extracellular regulated kinases (ERK1/2) and c-Jun N-terminal Kinases (JNK), are generally considered to play a key role in signal transduction pathways activated by a wide range of stimuli. We studied the effects of SP600125, a novel inhibitor of both JNK and ERK1/2, in male C57/BL6 mice given with an hyper-stimulating dose of cerulein (50 microg/kg for each of four injections at hourly intervals) to elicit secretagogue-induced pancreatitis. A control group received four intra-peritoneal injections of 0.9% saline at hourly intervals. Animals were randomized to receive either SP600125 (15 mg/kg i.p. administered 2 h before and 30 min after the first injection of cerulein) or its vehicle (1 ml/kg of a 10% DMSO/NaCl solution). A group of animals was killed 30 minutes after the last cerulein injection to evaluate pancreatic JNK and ERK1/2 activation by Western Blot analysis. Another group was sacrificed 2 hours after the last cerulein injection to evaluate serum lipase and amylase levels, pancreas oedema, pancreatic content of Tumor Necrosis Factor-alpha (TNF-alpha) and Intercellular adhesion molecule-1 (ICAM-1) and the histological alterations. SP600125 inhibited almost totally JNK activation (90%) and partially ERK1/2 activation (45%), reduced the serum lipase and amylase levels and the degree of oedema, blunted the increased pancreatic content of TNF-alpha and ICAM-1 and protected against the histological damage. Our data confirm that both JNK and ERK1/2 activation plays a key role in acute pancreatitis and that SP600125 may represent a potential therapeutic approach to the treatment of patients at high risk of developing this life-threatening condition.

Attenuated cerulein-induced pancreatitis in nuclear factor-kappaB-deficient mice

Nuclear factor (NF)-kappaB plays a central role in acute pancreatitis. We studied cerulein (CER)-induced pancreatitis in NF-kappaB knockout (KO) mice. NF-kappaB KO mice and normal control littermate wild-type (WT) mice were given four hyperstimulating doses of cerulein every hour to elicit secreatagogue-induced pancreatitis. Malonildialdehyde activity, glutathione levels, myeloperoxidase activity, TNF-alpha, and NF-kappaB binding activity and its inhibitory protein IkappaBalpha were studied in the pancreas. Furthermore, we measured plasma lipase and amylase and the histological damage. KO mice had reduced malonildialdehyde levels (WT + CER = 4.083 +/- 0.95 micromol/g; KO + CER = 1.513 +/- 0.63 microol/g), decreased myeloperoxidase activity (WT + CER = 19.3 +/- 2.39 mU/g; KO + CER = 10.21 +/- 2.05 mU/g), increased glutathione levels (WT + CER 6.22 +/- 2.46 micromol/g; KO + CER = 15. 516 +/- 2.92 micromol/g), and reduced serum levels of amylase (WT + CER = 2519 +/- 656.9 U/L; KO + CER = 916 +/- 280.4 U/L) and lipase (WT + CER = 1420 +/- 170 U/L; KO + CER = 861 +/- 172. 3 U/L). KO mice showed reduced pancreatic NF-kappaB activation, decreased TNF-alpha tissue content, and reduced histologic alterations. Our data suggest that KO mice have an attenuated cerulein-induced pancreatitis and help to define the possible interaction between NF-kappaB activation and oxidative stress in this deleterious event.

Gene transfer of IkappaBalpha limits infarct size in a mouse model of myocardial ischemia-reperfusion injury

Nuclear factor-kappaB (NF-kappaB) plays a central role in myocardial ischemia-reperfusion (MI/R) injury. The inhibitory protein IkappaBalpha prevents its activation. We investigated the effects of adeno-associated viral vector-mediated IkappaBalpha gene transfer in MI/R injury. Male C57BL/6 mice were randomized to receive a recombinant adeno-associated virus (rAAV) encoding the gene for the NF-kappaB inhibitory protein IkappaBalpha (rAAV- IkappaBalpha) or the beta-galactosidase gene (a control and inert gene; rAAV-LacZ), both at a dose of 10(11) copies. Four weeks later anesthetized animals were subjected to total occlusion (45 minutes) of the left main coronary artery followed by 5 hours of reperfusion. MI/R produced a wide infarct size (IF/area-at-risk = 56 +/- 8%; IF/left ventricle = 44 +/- 5%) and tissue neutrophil infiltration, studied by means of elastase activity (area-at-risk = 2.5 +/- 0.4 micro g/gm tissue; infarct area = 2.9 +/- 0.6 micro g/gm tissue). Furthermore MI/R caused peak message for intercellular adhesion molecule-1 (ICAM-1) in the area-at-risk at 3 hours of reperfusion (1.2 +/- 0.4 relative amount of cardiac ICAM-1 mRNA). NF-kappaB activation was evident at 0.5 hours of reperfusion and reached its maximum increase at 2 hours of reperfusion. rAAV-IkappaBalpha injection reduced infarct size (IF/area-at-risk = 19 +/- 3%; IF/left ventricle = 10 +/- 2%; p < 0.001), blocked NF-kappaB activation, diminished cardiac ICAM-1 expression (0.4 +/- 0.02 relative amount of cardiac ICAM-1 mRNA; p < 0.001), and blunted leukocyte accumulation (area-at-risk = 0.6 +/- 0.05 micro g/gm tissue; infarct area = 0.4 +/- 0.02 micro g/gm tissue; p < 0.001). Our data indicate that rAAV-IkappaBalpha may be useful for MI/R gene therapy.

Lipid peroxidation inhibition reduces NF-kappaB activation and attenuates cerulein-induced pancreatitis

Increased lipid peroxidation, enhanced nuclear factor kappa-B (NF-kappaB) activation and augmented tumor necrosis factor-alpha (TNF-alpha) production have been implicated in cerulein-induced pancreatitis. We investigated whether lipid peroxidation inhibition might reduce NF-kappaB activation and the inflammatory response in cerulein-induced pancreatitis. Male Sprague-Dawley rats of 230-250g body weight received administration of cerulein (80 microg/kg s.c. for each of four injections at hourly intervals). A control group received four s.c. injections of 0.9% saline at hourly intervals. Animals were randomized to receive either raxofelast, an inhibitor of lipid peroxidation (20 mg/kg i.p. administered with the first cerulein injection) or its vehicle (1 ml/kg of a 10% DMSO/NaCl solution). All these rats were sacrificed 2 h after the last injection of either cerulein or its vehicle. Raxofelast administration (20 mg/kg i.p. with the first cerulein) significantly reduced malondialdehyde (MDA) levels, an index of lipid peroxidation (CER + DMSO = 3.075 +/- 0.54 micromol/g; CER + raxofelast = 0.693 +/- 0.18 micromol/g; p < 0.001), decreased myeloperoxidase (MPO) activity (CER + DMSO = 22.2 +/- 3.54 mU/g; CER + raxofelast = 9.07 +/- 2.05 mU/g, p < 0.01), increased glutathione levels (GSH) (CER + DMSO = 5.21 +/- 1.79 micromol/g; CER + raxofelast = 15.71 +/- 2.14 micronol/g; p < 0.001), and reduced acinar cell damage evaluated by means of histology and serum levels of both amylase (CER + DMSO = 4063 +/- 707.9 U/l; CER + raxofelast = 1198 +/- 214.4 U/l; p < 0.001), and lipase (CER + DMSO = 1654 +/- 330 U/l; CER + raxofelast = 386 +/- 118.2 U/l; p < 0.001), Furthermore, raxofelast reduced pancreatic NF-kappaB activation and the TNF-alpha mRNA levels and tissue content of mature protein in the pancreas. Indeed, lipid peroxidation inhibition might be considered a potential therapeutic approach to prevent the severe damage in acute pancreatitis.

Effect of recombinant adeno-associated virus vector-mediated vascular endothelial growth factor gene transfer on wound healing after burn injury

OBJECTIVE

The purpose of this study was to investigate the effect of recombinant adeno-associated viral (rAAV) vector-mediated human vascular endothelial growth factor (VEGF165) transfer on experimental burn wounds.

DESIGN

Randomized experiment.

SETTING

Research laboratory.

SUBJECTS

C57BL/6 male mice weighing 25-30 g.

INTERVENTIONS

Mice were immersed in 80 degrees C water for 10 secs to achieve a partial-thickness scald burn. Animals were randomized to receive at two injection sites on the edge of the burn either 1011 copies of the rAAV-VEGF165 or the vector carrying the control and inert gene beta-galactosidase (rAAV-LacZ). On day 14 the animals were killed. Burn areas were used for histologic examination, evaluation of VEGF expression (immunohistochemistry) and VEGF wound content (enzyme-linked immunosorbent assay), determination of wound nitrite, and measurement of messenger RNA (mRNA) for endothelial and inducible nitric oxide synthase (eNOS and iNOS).

MEASUREMENTS AND MAIN RESULTS

rAAV-VEGF165 increased epithelial proliferation, angiogenesis, and maturation of the extracellular matrix. Furthermore, gene transfer enhanced VEGF expression, studied by immunohistochemistry, and the wound content of the mature protein (rAAV-LacZ, 11 +/- 5 pg/wound; rAAV-VEGF165, 104 +/- 7 pg/wound). Moreover, VEGF165 gene transfer increased wound content of nitrate. Finally, rAAV-VEGF165 administration enhanced the messenger RNA for eNOS (rAAV-VEGF165, 1.1 +/- 0.2 relative amount of eNOS mRNA; rAAV-LacZ, 0.66 +/- 0.3 relative amount of eNOS mRNA) and iNOS (rAAV-VEGF165, 0.8 +/- 0.09 relative amount of iNOS mRNA; rAAV-LacZ, 0.45 +/- 0.05 relative amount of iNOS mRNA).

CONCLUSION

Our study suggests that rAAV-VEGF gene transfer may be an effective therapeutic approach to improve clinical outcomes after thermal injury.

Efferent vagal fibre stimulation blunts nuclear factor-kappaB activation and protects against hypovolemic hemorrhagic shock

BACKGROUND

We investigated whether electrical stimulation (STIM) of efferent vagus nerves may suppress nuclear factor (NF)-kappaB activation and the inflammatory cascade in hemorrhagic (Hem) shock.

METHODS AND RESULTS

Rats were subjected to bilateral cervical vagotomy (VGX) or sham surgical procedures. Hem shock was induced by intermittent withdrawing of blood until mean arterial pressure stabilized within the range of 35 to 40 mm Hg. Application of constant voltage pulses to the caudal vagus ends (STIM; 5 V, 2 ms, 1 Hz for 12 minutes, 5 minutes after mean arterial pressure stabilization) increased survival time (VGX+Hem+Sham STIM=38+/-3 minutes; VGX+Hem+STIM >180 minutes), reverted the marked hypotension (VGX+Hem+Sham STIM=33+/-3 mm Hg; VGX+Hem+STIM=66+/-5 mm Hg), inhibited IkappaBalpha liver loss, and blunted the augmented NF-kappaB activity, decreased hepatic tumor necrosis factor (TNF)-alpha mRNA (VGX+Hem+Sham STIM=1.42+/-0.5 amount of TNF-alpha m-RNA; VGX+Hem+STIM=0.51+/-0.2 amount of TNF-alpha mRNA), and reduced plasma TNF-alpha (VGX+Hem+Sham STIM=190+/-24 pg/mL; VGX+Hem+STIM=87+/-15 pg/mL). Chlorisondamine, a nicotinic receptor antagonist, abated the effects of vagal stimulation.

CONCLUSIONS

Our results show a parasympathetic inhibition of NF-kappaB by which the brain opposes NF-kappaB activation in the liver and modulates the inflammatory response during acute hypovolemic hemorrhagic shock.

Crucial role of nuclear factor-kappaB in neointimal hyperplasia of the mouse carotid artery after interruption of blood flow

We used a molecular genetics approach to investigate the role of nuclear factor-kappaB (NF-kappaB) in neointimal hyperplasia induced by flow interruption of carotid artery in mice. Wild type mice (WT mice) and mice rendered deficient in p105, the precursor of p50, one of the components of the multimeric transcription factor NF-kappaB (NF-kappaB knockout mice; KO mice), were subjected to a complete ligation of the left common carotid artery. Morphometric analysis of the structural alteration caused by the disruption of the arterial blood flow was performed 14 days after surgery. Furthermore the expression of intercellular adhesion molecule-1 (ICAM-1) in injured arteries was evaluated 4 days after artery ligation by the means of reverse transcriptase polymerase chain reaction (RT-PCR) and quantification of the ICAM-1 protein levels. In a separate experiment normal mice were randomly assigned to receive a recombinant adeno-associated virus (rAAV) encoding the gene for the NF-kappaB inhibitory protein IkappaBalpha (rAAV-IkappaBalpha), or the beta-galactosidase gene (rAAV-LacZ), both at a dose of 10(11) copies and 2 weeks later were subjected to the complete ligation of the left carotid artery. NF-kappaB activity (studied by means of electrophoretic mobility shift assay-EMSA), IkappaBalpha expression (evaluated by Western blot analysis) ICAM-1 evaluation (RT-PCR and quantification of the protein levels) and a morphometric analysis were evaluated in the injured arteries. Disruption of the arterial blood flow caused a marked neointimal hyperplasia. The mean intimal area was 0.023+/-0.002 mm(2) in wild type mice compared with 0.002+/-0.001 mm(2) in NF-kappaB knockout mice. ICAM-1 expression was 1.7+/-0.8 relative amount of ICAM-1 mRNA in wild type mice compared with 0.4+/-0.06 relative amount of ICAM-1 mRNA in NF-kappaB knockout mice. ICAM-1 protein levels were also significantly reduced in NF-kappaB knockout mice. Injured arteries treated with rAAV-IkappaBalpha had a greater expression of IkappaBalpha and lower NF-kappaB activity, when compared with vessels treated with rAAV-LacZ. Furthermore, ICAM-1 expression was markedly attenuated by the treatment with rAAV-IkappaBalpha (rAAV-LacZ=1.6+/-0.8 relative amount of ICAM-1 mRNA; rAAV-IkappaBalpha=0.55+/-0.04 relative amount of ICAM-1 mRNA). ICAM-1 protein levels were also significantly decreased in rAAV-IkappaBalpha treated mice. Finally the mean intimal area was 0.028+/-0.003 mm(2) in left carotid arteries treated with rAAV-LacZ whereas it was 0.003+/-0.004 mm(2) in vessels treated with rAAV-IkappaBalpha. Our data indicate that NF-kappaB plays a crucial role in neointimal hyperplasia induced by flow cessation in the mouse carotid artery, and in addition suggest that rAAV-mediated gene transfer of IkappaBalpha might represent a novel therapeutic approach to the treatment of restenosis.

Nuclear factor-kappaB as a target of cyclosporin in acute hypovolemic hemorrhagic shock

BACKGROUND

Cyclosporin is an immunosuppressive drug that blocks Nuclear Factor kappaB (NF-kappaB) activation. We investigated the role of NF-kappaB in acute hypovolemic hemorrhagic (Hem) shock and the effects of cyclosporin in this model of experimental shock.

METHODS

Hem shock was induced in male anesthetized rats by intermittently withdrawing blood from an iliac catheter over a period of 20 min (bleeding period) until mean arterial blood pressure (MAP) fell and stabilized within the range of 20-30 mmHg. Two minutes after bleeding cessation, animals received intravenously cyclosporin (1 mg kg(-1)) or its vehicle. Survival rate and survival time were evaluated for 120 min after bleeding was discontinued. Plasma TNF-alpha levels were investigated at different time points after bleeding cessation. Moreover we investigated levels of TNF-alpha mRNA in the liver, vascular reactivity, liver NF-kappaB binding activity and levels of the inhibitory protein IkappaBalpha in the cytoplasm.

RESULTS

Hemorrhagic shocked rats died in 27+/-6 min following the cessation of bleeding, experienced a marked hypotension (mean arterial blood pressure=20-30 mmHg) and had enhanced plasma levels of Tumor Necrosis Factor-alpha (208+/-22 pg ml(-1), 20 min after the end of bleeding). Furthermore, aortas taken 20 min after bleeding from hemorrhagic shocked rats showed a marked hypo-reactivity to phenylephrine (PE: 1 nM-10 microM) compared with aortas harvested from sham shocked rats. Hem shocked rats also had increased levels of TNF-alpha mRNA in the liver (15-20 min after the end of bleeding). Electrophoretic mobility shift assay showed that liver NF-kappaB binding activity increased in the nucleus 10 min after the end of hemorrhage and remained elevated until the death of animals. Western blot analysis suggested that the levels of inhibitory protein IkappaBalpha in the cytoplasm decreased at 5 min after the end of bleeding. Cyclosporin inhibited the loss of IkappaBalpha protein from the cytoplasm and prevented NF-kappaB binding activity in the nucleus. Furthermore, cyclosporin increased survival time (118+/-7 min; P<0.01) and survival rate (vehicle=0% and cyclosporin=80%, at 120 min after the end of bleeding), reverted the marked hypotension, decreased liver mRNA for TNF-alpha, reduced plasma TNF-alpha (28+/-7 pg ml(-1)), and restored to control values the hypo-reactivity to PE.

CONCLUSIONS

Our results suggest that acute blood loss (50% of the estimated total blood volume over a period of 20 min) causes early activation of NF-kappaB which triggers an inflammatory cascade leading to a fatal outcome. Cyclosporin blocks NF-kappaB activation and protects against hypovolemic hemorrhagic shock.

Factors associated with hypotension and bradycardia after epidural blockade

In order to identify patient-, anesthesia-, and surgery-related factors influencing the probability of hypotension and bradycardia after epidural blockade, an observational study was conducted on 1050 nonpregnant patients. Backward stepwise logistic regression was performed on the variables hypotension (systolic blood pressure < 90 mm Hg) and bradycardia (heart rate < or = 45 bpm). Hypotension and bradycardia occurred in 158 and 24 patients, respectively. The probability of hypotension increased when epidural fentanyl was administered (odds ratio [OR] = 2.18; 95% confidence interval [CI] = 1.16-4.11), with body weight and spread of epidural analgesia, and decreased when a tourniquet was used (OR = 0.01, CI = 0.01-0.02) and bupivacaine instead of carbonated lidocaine was administered (OR = 0.28, CI = 0.14-0.60). Sensitivity and specificity of the model were 89% and 88%, respectively. The probability of bradycardia was less in women (OR = 0.05, CI = 0.01-0.41) and when a tourniquet was used (OR = 0.04, CI = 0.02-0.09). Sensitivity and specificity were 50% and 97%, respectively. In conclusion, our analysis can contribute to identification of patients at high risk to develop hypotension and bradycardia after epidural blockade. If bupivacaine instead of carbonated lidocaine is used and epidural fentanyl is not administered a decrease in the incidence of hypotension may be anticipated.

A multifactorial analysis to explain inadequate surgical analgesia after extradural block

A multivariate analysis of inadequate extradural analgesia was carried out prospectively on 1051 patients undergoing lumbar extradural anaesthesia for surgery performed on structures innervated by T10-S5. Ninety-six patients (9%) experienced pain during surgery. Age, extradural fentanyl, diazepam sedation and duration of surgery had no significant influence. We found some weak evidence that the type of surgery affects the risk of feeling pain. The probability of pain increased with increasing weight, except in overweight women, and was significantly greater for both shorter and taller patients, relative to patients of average height. The probability of pain decreased with increasing dose of local anaesthetic, increasing spread of extradural analgesia, addition of adrenaline, and fentanyl or thiopentone sedation. In conclusion, patient-, surgery- and anaesthesia-related factors influence the risk of inadequate extradural analgesia. If such factors are taken into account, an increase in the success rate may be anticipated.

Failure rate of epidural anaesthesia for foot and ankle surgery. A comparison with other surgical procedures

To test whether epidural anaesthesia for foot and ankle surgery is associated with an unacceptably high incidence of inadequate surgical analgesia, we prospectively compared two groups of patients, one undergoing foot or ankle surgery (160 patients) and the other surgical procedures not performed in areas innervated by L5-S1 ( (168 patients). Lumbar epidural anaesthesia was performed in both groups by administering carbonated lignocaine 2% with adrenaline 1:200000. Seven patients in the foot-ankle group (4.4%) and 10 in the group for comparison (5.9%) exhibited inadequate surgical analgesia. This difference is not statistically significant. Within the foot-ankle group, a significantly lower dose of local anaesthetic per spinal segment had been given to patients who displayed inadequate analgesia, compared with those who exhibited satisfactory analgesia (P < 0.05).

A multifactorial analysis of the spread of epidural analgesia

The controversies about the factors determining the spread of epidural analgesia are partly due to inappropriate methodology or sample size of previous studies. We performed a multivariate regression analysis on 803 ASA class 1-2 non-atherosclerotic adults, undergoing lumbar epidural anaesthesia according to a predefined standardised procedure. The spread of epidural analgesia is more accurately studied by analysing dose/segment (R2 = 0.671) instead of spread (R2 = 0.271) as dependent variable. The impact of local anaesthetic (2% lidocaine CO2 or 0.5% bupivacaine) and addition of adrenaline is not significant. Spread significantly increases with increasing age, weight, body-mass index, dose of local anaesthetic, addition of fentanyl, higher site of injection, and decreasing body height. The impact of age and dose is higher under the age of 40 and at doses lower than 20 ml. Increasing the total dose increases the dose needed to block one spinal segment. Unknown idiosyncratic factors still determine a certain proportion of the sample variance. The addition of adrenaline to lidocaine and the use of bupivacaine improve the predictability of spread. In conclusion, we found clinically significant correlations between a group of factors and epidural spread. Alternative anaesthetic solutions lead to different degrees of predictability.

[Comparison of carbonated lidocaine and mepivacaine in epidural anesthesia]

OBJECTIVE

To compare carbonated mepivacaine to carbonated lidocaine in epidural anaesthesia.

DESIGN

Nonrandomised control trial.

SETTING

University Hospital.

PATIENTS

Forty patients undergoing epidural anaesthesia for orthopaedic surgery.

METHODS

Epidural anaesthesia at the fourth lumbar interspace, administering either carbonated mepivacaine 20 ml (group M, 20 patients) or carbonated lidocaine 20 ml (group L, 20 patients). Parameters recorded: onset of sensory block (time required to reach L1 and time required to reach the upper level), cranial spread of analgesia (number of dermatomes), duration of block (time between achievement of maximum spread of analgesia and regression of sensory block by two dermatomes) and motor block (Bromage score).

RESULTS

No statistically significant differences have been found between group M and group L in the time required to reach L1 (means and standard deviations 6.3 +/- 3.8 and 6.5 +/- 2.1 minutes, respectively), in the time required to reach the upper level of analgesia (means and standard deviations 14.3 +/- 4.2 and 16.5 +/- 3.5 minutes, respectively), in the cranial spread of analgesia (means and standard deviations 7.1 +/- 3.4 and 7.6 +/- 2.7 dermatomes, respectively) and in the degree of motor block (means and standard deviations 1.5 +/- 0.8 and 1.1 +/- 0.8, respectively). Group M exhibited a much higher duration of sensory block, compared to group L (means and standard deviations 91.6 +/- 20.2 and 58.8 +/- 23.4 minutes, respectively, p < 0.001).

CONCLUSIONS

Carbonated mepivacaine is more indicated than carbonated lidocaine in epidural anaesthesia when a high duration of sensory block is desired.

[Postoperative pain in shoulder surgery]

Postoperative shoulder pain should be adequately treated not only because of the high severity of the symptomatology often observed, but also because pain and muscle contraction render impossible an early rehabilitation programme. Regional anaesthesia, by virtue of its beneficial effects on the pathophysiology of pain and its influence on the rehabilitative problems of shoulder surgery, is the most adequate technique for the control of postoperative pain.

[Propofol and alfentanil in total intravenous anesthesia]

We studied 22 patients undergoing total intravenous anaesthesia for both abdominal and superficial surgery. Anaesthesia has been induced and maintained with propofol (1 mg/kg in 20 seconds; 10 mg/kg/h for 10 minutes; 8 mg/kg/h for 10 minutes; 6 mg/kg/h until the end of the operation) and alfentanil (15 mg/kg before the induction and boli of 10-30 mg/kg in the presence of insufficient surgical analgesia). All the patients have been intubated after the administration of vecuronium 0.1 mg/kg, and artificially ventilated with air and oxygen (FiO2 0.4). We observed: 1) haemodynamic stability after the intubation and during surgery; 2) easy control of surgical analgesia; 3) early postoperative recovery, with no correlation with the doses of propofol and alfentanil; 4) absence of postoperative respiratory depression; 5) intraoperative amnesia; 6) low incidence of postoperative side effects. We conclude that, by virtue of the pharmacokinetic characteristics of propofol and alfentanil, most limitations of total intravenous anaesthesia have been overcome.

[Sedation with propofol in COPD patients in the ICU]

Sedation with propofol was achieved in 10 patients with COPD admitted into ICU because of acute respiratory insufficiency. Propofol dosage was 1-3 mg/kg-1/h and the testing period 30-144 h. Curarization was non required. Sedation with propofol, valued by means of Ramsay Score, was suitable in all tested patients. Bio-humoral and instrumental monitoring have not evidenced side effects.

[Pressure changes in the middle ear during nitrous oxide anesthesia]

We studied middle ear pressure variations in 17 patients with mild upper airways or middle ear diseases, during nitrous oxide anaesthesia. We observed a significant increase in middle ear pressure during the administration of nitrous oxide, and a significant decrease after nitrous oxide was discontinued. Nine patients showed periodical reductions of the middle ear pressure during the inhalation of nitrous oxide, due to passive openings of the eustachian tube. In the remaining 8 patients (47%) this mechanism has not been effective. A comparison between these two groups shows significantly higher levels of middle ear pressure in the group of patients with abnormal function of the eustachian tube, both during and after the administration of nitrous oxide. Our results demonstrate that patients with mild upper airways or middle ear diseases are likely to show an impaired tubal function. Therefore, nitrous oxide should be used with caution in the presence of such diseases. Moreover, nitrous oxide is generally controindicated in middle ear surgery, as the pressure gradients between middle and external ear can jeopardize the success of the operation.

[New methods of electrophysiologic investigation in the diagnosis of brain death]

In the event of suspected brain death it is vital to arrive at a diagnosis as rapidly as possible and with the least chances of error. The paper examines the potentially and possible value of BAER recordings. Results are in line with those of other published studies which underline the value of this method, in spite of the fact it is limited by the possible presence of numerous factors which might invalidate recordings.

[Comparison of a combination of fentanyl and alfentanil with propofol in brief surgery]

We studied 96 patients undergoing short gynecological procedures. Anaesthesia has been induced with fentanyl 1.5 micrograms/kg (45 patients) or alfentanil micrograms /kg (51 patients) and a hypnotic dose of propofol, and maintained with 70% N2O via facial mask. We observed a better and more rapid control of surgical analgesia with alfentanil, and an earlier recovery of postoperative psychophysical functions. Post-induction apnea has been more frequent and prolonged in the alfentanil group, but no difference in the time necessary to recover an adequate ventilation has been observed between the two groups. Alfentanil anaesthesia determined a more marked intraoperative bradycardia. By virtue of the speed of onset and the short duration of action, alfentanil is a suitable anaesthetic agent for short surgical procedures, particularly in day-stay patients.

[Anesthesia for shoulder surgery. Comparison of anesthesiologic problems and technics]

We evaluated the ability of general, regional (interscalene block) and balanced anaesthesia (interscalene block supplemented by general anaesthesia) to manage the problems of shoulder surgery. Our results show that general anaesthesia is not adequate. Interscalene block provides intra and postoperative analgesia, allows an early realization of the postoperative rehabilitation programme and quickens the recovery of shoulder function. Therefore, interscalene block should routinely be performed. The positions of patient and surgeons cause the main disadvantages of anaesthesia with interscalene block alone, ad the control of airway of sedated patients is difficult and performing general anaesthesia in case of insufficient analgesia may be troublesome. Balanced anaesthesia, as compared to regional block alone, allows a safer control of respiration and an easier control of surgical analgesia.

[Muscular rigidity caused by alfentanil: prevention]

We studied three groups of 30 patients each, undergoing minor orthopaedic surgery, anaesthetized with alfentanil (30 micrograms/kg bolus followed by an infusion of 0.3 micrograms/kg/min), thiopental 3 mg/kg and 70% N2O via facial mask. Patients in group I were treated, three minutes before induction, with vecuronium 0.02 mg/kg i.v., while those in group II were premedicated with diazepam 0.15 mg/kg i.m. 30-45 minutes before induction. Group III served as control. Muscular rigidity was evaluated clinically with a subjective score based on a scale of 0 (no rigidity) to 3 (severe rigidity). Diazepam did not give significant protection from muscular rigidity. Vecuronium administration did not significantly reduced the number of patients who became rigid, but significantly decreased the incidence of severe rigidity (p less than 0.005), the mean rigidity score (p less than 0.05) and the incidence of rigidity at the induction of anaesthesia (p less than 0.0005). We also observed a progressively increasing incidence of rigidity with increasing age (not significantly) and body weight (p less than 0.05 total rigidity, p less than 0.01 severe rigidity).