Montserrat Rigol - Academia.edu (original) (raw)
Papers by Montserrat Rigol
European Journal of Clinical Investigation, 2003
High plasma levels of angiotensin II are found in several pathologies such as hypertension, heart... more High plasma levels of angiotensin II are found in several pathologies such as hypertension, heart failure and myocardial infarction. The effect of high concentrations of angiotensin II on coronary circulation is not well defined. The aim of the present study was to assess coronary blood flow regulation during tachycardia in the presence of elevated coronary plasma levels of angiotensin II, and the changes induced by ACE inhibition and blockade of angiotensin II and endothelin-A receptors. Left anterior coronary artery was catheterized in 38 pigs to infuse the study drugs. Saline was infused for 15 min. Then, the first atrial pacing was performed. The pigs were distributed to: Group 1 (n = 7) angiotensin II; Group 2 (n = 7) enalaprilat + angiotensin II; Group 3 (n = 9) the bradykinin B2 antagonist HOE 140 + enalaprilat + angiotensin II; Group 4 (n = 7) losartan + angiotensin II; and Group 5 (n = 8) endothelin-A receptor antagonist LU 135252 + angiotensin II. After giving these infusions, a second pacing was repeated. The increase in coronary blood flow induced by pacing with angiotensin II was reduced from 181 +/- 21% to 116 +/- 37% (P = 0.006 vs. saline). Enalaprilat, losartan and LU 135252 restored the capacity of coronary blood flow to increase during pacing (151 +/- 39%, 162 +/- 35% and 161 +/- 16%, respectively; P = NS, vs. saline), while HOE 140 abolished the effect of enalaprilat. Moderately elevated coronary concentrations of angiotensin II reduced coronary blood flow during pacing. Enalaprilat, losartan and LU 135252 restored the hyperaemic coronary flow to similar values observed with saline. The beneficial effect of ACE inhibition is mediated through an increase in bradykinin.
European Respiratory Journal, 2010
Staphylococcus aureus is one of the most common causes of nosocomial pneumonia contributing to si... more Staphylococcus aureus is one of the most common causes of nosocomial pneumonia contributing to significant morbidity and mortality. Therapeutic options for patients with methicillin-resistant S. aureus (MRSA) infection are limited. In addition, little is known about the S. aureus virulence factors that may influence the presentation and prognosis of severe lower respiratory tract infections. Animal models of severe pneumonia allow investigators to control and exclude potential confounders and to examine the influence of comorbid conditions. Therefore, these models may improve our knowledge of the intimate pathophysiological mechanisms affecting pharmacodynamics, pharmacokinetics and efficacy of therapy. So far, animal research studies on MRSA and vancomycin-resistant S. aureus, performed both in small and large animal models, have improved knowledge of the mechanisms of disease, which may lead to a better treatment for this severe and complex infection in humans.
Transplantation Proceedings, 2008
BackgroundThe aim of the present research was to study the possible interference of hemosiderin d... more BackgroundThe aim of the present research was to study the possible interference of hemosiderin deposits with the histological detection of dextran-coated, iron-labeled, mesenchymal stem cells after intracoronary administration in a porcine model of myocardial infarction.
Revista Espa de Cardiologia
The mechanisms by which estradiol dilates arterial vessels are still unclear. Our aim was to stud... more The mechanisms by which estradiol dilates arterial vessels are still unclear. Our aim was to study if estradiol enhances endothelium-dependent vasodilation in an experimental model of human arteries in vitro, and if this effect is nitric oxide mediated. Using organ bath chambers, we studied 18 arterial rings obtained from left internal mammary arteries during coronary artery bypass grafting surgery. Response to acetylcholine was evaluated at baseline and after the addition of estradiol 10-6 mol/l to the medium, both in the presence or absence of a nitric oxide synthase inhibitor (L-NNA 10-4 mol/l). Estradiol significantly enhanced the relaxation of the arterial rings in response to acetylcholine (52 +/- 20% after estradiol versus 42 +/- 22% at baseline; n = 10; p = 0.02). However, endothelium-dependent vasodilation relaxation after estradiol addition was not enhanced in the presence of L-NNA (47 +/- 25% after estradiol versus 38 +/- 22% at baseline; n = 8; p = NS). Estradiol in vitr...
P-selectin (CD62P), an adhesion molecule expressed on activated endothelial cells and platelets, ... more P-selectin (CD62P), an adhesion molecule expressed on activated endothelial cells and platelets, mediates the initial attachment of leukocytes to the stimulated endothelium upon inflammation and the interaction between leukocytes and platelets. A soluble form of P-selectin is present in the serum of healthy individuals as a circulating protein and high levels have been described in various pathological situations. The aim of this study was to characterize P-selectin on porcine platelets and investigate the soluble form of this protein, which are uncharacterized in several animal species including pigs. A new monoclonal antibody (mAb) (SwPsel.1.9) against porcine P-selectin was produced using a mouse cell line transfected with pig P-selectin cDNA. This mAb together with a previously described mAb (P-sel.KO.2.5), produced in our laboratory, was used to develop an ELISA to quantify porcine P-selectin. No significant levels of soluble-porcine P-selectin were observed in healthy animals. However, the total amount of P-selectin measured in porcine platelets was similar to that found in humans. Increased levels of this circulating protein were detected in the plasma from pigs after allograft implantation. In vitro, P-selectin expression on platelet membrane was rapidly induced by PMA and thrombin, as assessed by flow cytometry. However, these activators did not stimulate the release of soluble P-selectin. Analysis of the proteolytic cleavage of this protein from COS-transfected cells revealed that PMA treatment failed to cause the shedding of membrane-bound P-selectin. These data suggest that porcine Pselectin is a suitable marker for inflammation and that the mechanism involved in the generation of circulating P-selectin is not proteolytic release. #
Journal of The American College of Cardiology, 1998
Critical Care, 2015
Laboratory studies demonstrated that the lateral Trendelenburg position (LTP) is superior to the ... more Laboratory studies demonstrated that the lateral Trendelenburg position (LTP) is superior to the semirecumbent position (SRP) in the prevention of ventilator-associated pulmonary infections. We assessed whether the LTP could also prevent pulmonary colonization and infections caused by an endotracheal tube (ETT) biofilm. Eighteen pigs were intubated with ETTs colonized by Pseudomonas aeruginosa biofilm. Pigs were positioned in LTP and randomized to be on mechanical ventilatin (MV) up to 24 hour, 48 hour, 48 hour with acute lung injury (ALI) by oleic acid and 72 hour. Bacteriologic and microscopy studies confirmed presence of biofilm within the ETT. Upon autopsy, samples from the proximal and distal airways were excised for P.aeruginosa quantification. Ventilator-associated tracheobronchitis (VAT) was confirmed by bronchial tissue culture ≥3 log colony forming units per gram (cfu/g). In pulmonary lobes with gross findings of pneumonia, ventilator-associated pneumonia (VAP) was confirmed by lung tissue culture ≥3 log cfu/g. P.aeruginosa colonized the internal lumen of 16 out of 18 ETTs (88.89%), and a mature biofilm was consistently present. P.aeruginosa colonization did not differ among groups, and was found in 23.6% of samples from the proximal airways, and in 7.1% from the distal bronchi (P = 0.001). Animals of the 24 hour group never developed respiratory infections, whereas 20%, 60% and 25% of the animals in group 48 hour, 48 hour-ALI and 72 hour developed P.aeruginosa VAT, respectively (P = 0.327). Nevertheless, VAP never developed. Our findings imply that during the course of invasive MV up to 72 hour, an ETT P.aeruginosa biofilm hastily colonizes the respiratory tract. Yet, the LTP compartmentalizes colonization and infection within the proximal airways and VAP never develops.
European Journal of Clinical Investigation, 2000
Myocardial ischaemia and left ventricular dysfunction have been described in cocaine users. Wheth... more Myocardial ischaemia and left ventricular dysfunction have been described in cocaine users. Whether nitric oxide (NO) inhibition may potentiate the effects of cocaine on coronary circulation and ventricular function is still unknown. In order to test this hypothesis, 38 pentobarbital-anaesthetized pigs were instrumented for systolic blood pressure, coronary blood flow, left ventricular dp/dt, cardiac output, left ventricular end-diastolic and end-systolic lengths and shortening fraction. The pigs were randomized into three groups: control group: i.v. saline (n = 5); group 1: i.v. cocaine, 10 mg kg-1 over 20 min (n = 17); group 2: the same doses of cocaine 30 min after i.c. L-NAME 20 microg/kg min-1 infusion (n = 16). In order to know whether the observed effects were specific of NO inhibition, in five pigs i.c. L-arginine was simultaneously infused with L-NAME, in five pigs i.c. NTG, an endothelial-independent vasodilator, was simultaneously infused with L-NAME before cocaine was administered, and in nine additional pigs the proximal left anterior descending (LAD) flow was reduced to around 20% of the basal value by means of a mechanical occluder before cocaine was administered. Cocaine i.v did not change the coronary blood flow, while it induced a significant reduction in cardiac output, left ventricular dp/dt and shortening fraction (15 +/- 4-8 +/- 4%, P < 0.05). When cocaine was administered after L-NAME infused i.c. during 30 min, a significantly more severe reduction of the shortening fraction (12 +/- 3-4 +/- 2%, P < 0.0001) was induced; this effect was abolished by simultaneous perfusion of L-arginine i.c. NTG. The results when cocaine was administered after the 20% LAD flow reduction by mechanical occluder did not differ from those of cocaine alone. NO inhibition intensifies the cocaine-induced left ventricular dysfunction.
Journal of Cardiovascular Translational Research, 2013
Animal models that mimic human electrical and mechanical dyssynchrony often associated with chron... more Animal models that mimic human electrical and mechanical dyssynchrony often associated with chronic heart failure would provide an essential tool to investigate factors influencing response to cardiac resynchronization therapy. A standardized closed-chest porcine model of left bundle branch block (LBBB) was developed using 16 pigs. Radiofrequency applications were performed to induce LBBB, which was confirmed by QRS widening, a surface electrocardiogram pattern concordant with LBBB, and a prolonged activation time from endocardial. Echocardiography confirmed abnormal motion of the septum, which was not present at the baseline echocardiogram. High susceptibility of pigs to ventricular fibrillation during the endocardial ablation was overcome by applying high-rate pacing during radiofrequency applications. This is the first study to devise a closed-chest porcine model of LBBB that closely reproduces abnormalities found in patients with electrical and mechanical cardiac dyssynchrony, and provides a useful tool to investigate the basic mechanisms underlying cardiac resynchronization therapy benefits in heart failure.
Revista Española de Cardiología, 2000
ABSTRACT Background The role of different endothelium-derived vasoactive substances in the regula... more ABSTRACT Background The role of different endothelium-derived vasoactive substances in the regulation of coronary circulation during tachycardia is not well defined. In order to elucidate the contribution of prostacyclin to the adaptation of coronary blood flow to tachycardia, the effect of meclofenamate, a cyclooxygenase inhibitor on the coronary blood flow response to rapid atrial pacing was analyzed in a porcine model. Methods A group of seventeen pigs were instrumented for coronary blood flow, aortic pressure and atrial pacing. Heart rate was increased by 20 beats every 5 minutes. Coronary blood flow and aortic pressure were measured, and coronary resistance calculated, basally and at each pacing interval, before and after saline serum (n = 6), meclofenamate 5 mg/kg, i.v. (n = 7) or meclofenamate 35 mg/kg, i.v. (n = 4). Results Neither saline nor meclofenamate modified the normal increase of coronary blood flow provoked by rapid atrial pacing (163 ± 28% increase before versus 172 ± 29% after saline; 159 ± 21% increase before versus 161 ± 22% after meclofenamate low dosis and 201 ± 39% before vs 172 ± 36 after meclofenamate high dosis). There were no differences in the response of coronary vascular resistance to tachycardia before and after meclofenamate (44% reduction vs 40% respectively). Conclusion Cyclooxygenase blockade does not modify the response of coronary circulation to rapid atrial pacing, suggesting that prostacyclin does not play a limiting role in the regulation of coronary blood flow during tachycardia in this model.
D62. NOSOCOMIAL INFECTIONS: BACTERIOLOGY, DRUG RESISTANCE, AND OUTCOMES, 2012
B107. BACTERIAL PNEUMONIA: BIOMARKERS, RESISTANT PATHOGENS AND OUTCOMES, 2011
B107 BACTERIAL PNEUMONIA: BIOMARKERS, RESISTANT PATHOGENS AND OUTCOMES Monday, May 16/2:00 PM-4:3... more B107 BACTERIAL PNEUMONIA: BIOMARKERS, RESISTANT PATHOGENS AND OUTCOMES Monday, May 16/2:00 PM-4:30 PM / Room 401-402 (Street Level), Colorado Convention Center ... A Novel Ventilatory Strategy To Prevent Bacterial Translocation From The Oropharynx ...
B42. INVASIVE MECHANICAL VENTILATION: SOUP TO NUTS, 2010
/ Thematic Poster Session / Monday, May 17/8:15 AM-4:00 PM / B42 INVASIVE MECHANICAL VENTILATION:... more / Thematic Poster Session / Monday, May 17/8:15 AM-4:00 PM / B42 INVASIVE MECHANICAL VENTILATION: SOUP TO NUTS ... Area H, Hall G (First Level), Morial Convention Center ... Effects of Manual Rib Cage Compression On Peak Expiratory Flow And Mucus Clearance ...
Journal of Liquid Chromatography & Related Technologies - J LIQ CHROMATOGR RELAT TECHNO, 2012
Simple and specific analytical methods were developed and validated to quantify vancomycin in pla... more Simple and specific analytical methods were developed and validated to quantify vancomycin in plasma and lung tissue, which were obtained from a model of pneumonia in mechanically ventilated piglets. Tissue and plasma samples were precipitated and centrifuged; 100 µL of the supernatant were injected into the chromatographic system. Ceftazidime was used as the internal standard. The stationary phase was a silica based column Symmetry300 C18 (150 × 4.6 mm) with pre-column. The mobile phase consisted of 20% ultrafiltered water and 80% of (A) 75 mM sodium acetate buffer (pH = 3) with (B) acetonitrile (92%/8%;v/v). Isocratic flow rate was set at 0.8 mL/min and 0.7 mL/min for plasma and tissue samples, respectively. UV absorbance detection was set at 230 nm. Standard curves showed good linearity for plasma and pulmonary tissue (r > 0.99). The lower limits of quantitation were 1.56 µg/mL and 3.13 µg/mL for plasma and tissue, respectively. The intra- and inter-day precisions and accuracy...
Veterinary Immunology and Immunopathology, 2003
P-selectin (CD62P), an adhesion molecule expressed on activated endothelial cells and platelets, ... more P-selectin (CD62P), an adhesion molecule expressed on activated endothelial cells and platelets, mediates the initial attachment of leukocytes to the stimulated endothelium upon inflammation and the interaction between leukocytes and platelets. A soluble form of P-selectin is present in the serum of healthy individuals as a circulating protein and high levels have been described in various pathological situations. The aim of this study was to characterize P-selectin on porcine platelets and investigate the soluble form of this protein, which are uncharacterized in several animal species including pigs. A new monoclonal antibody (mAb) (SwPsel.1.9) against porcine P-selectin was produced using a mouse cell line transfected with pig P-selectin cDNA. This mAb together with a previously described mAb (P-sel.KO.2.5), produced in our laboratory, was used to develop an ELISA to quantify porcine P-selectin. No significant levels of soluble-porcine P-selectin were observed in healthy animals. However, the total amount of P-selectin measured in porcine platelets was similar to that found in humans. Increased levels of this circulating protein were detected in the plasma from pigs after allograft implantation. In vitro, P-selectin expression on platelet membrane was rapidly induced by PMA and thrombin, as assessed by flow cytometry. However, these activators did not stimulate the release of soluble P-selectin. Analysis of the proteolytic cleavage of this protein from COS-transfected cells revealed that PMA treatment failed to cause the shedding of membrane-bound P-selectin. These data suggest that porcine Pselectin is a suitable marker for inflammation and that the mechanism involved in the generation of circulating P-selectin is not proteolytic release. #
Transplantation Proceedings, 2008
Background. The aim of the present research was to study the possible interference of hemosiderin... more Background. The aim of the present research was to study the possible interference of hemosiderin deposits with the histological detection of dextran-coated, iron-labeled, mesenchymal stem cells after intracoronary administration in a porcine model of myocardial infarction. Materials and methods. A myocardial infarction was induced in six animals that received intracoronary iron-labeled autologous mesenchymal stem cells (group 1; n ϭ 2) or placebo (group 2; n ϭ 4). Six control animals without myocardial infarction underwent direct intramyocardial injections of iron-labeled autologous mesenchymal stem cells (group 3; n ϭ 2) or placebo (group 4; n ϭ 4). Histological sections from explanted hearts were stained with Prussian blue to identify dextran-coated, iron-labeled, mesenchymal stem cells. Results. After Prussian blue staining, granular blue labeling in the tissue was observed in both groups of animals with infarcts. Similar granular blue labeling was detected in hearts from control animals without infarction that had received iron-labeled mesenchymal stem cells. However, hearts from control animals without infarction that received placebo did not have any granular blue labeling in the tissue. Conclusions. Hemosiderin from infarction hemorrhage interferes with detection of dextran-coated iron-labeled mesenchymal stem cells after intracoronary administration, suggesting that this marker is not useful to detect mesenchymal stem cells in a porcine model of myocardial infarction.
Transplantation Proceedings, 2004
The need for arterial grafts in coronary surgery to complement autologous vessels has generated i... more The need for arterial grafts in coronary surgery to complement autologous vessels has generated interest in cryopreservation of small diameter allografts. We evaluated functional and histologic changes occurring in cryopreserved allografts 3 months after porcine femoral artery transplants. Methods. Twenty recipient and 15 donor pigs included a control group of 16 fresh and 12 cryopreserved nonimplant arteries were used. Fresh (n ϭ 5) and cryopreserved (n ϭ 5) autografts were implanted to assess cryopreservation effects in the absence of rejection. Fresh allografts with or without treatment with cyclosporine (CsA) (n ϭ 6 of 8) and cryopreserved allografts with or without treatment with CsA (n ϭ 6 of 10) were performed to study the antigenicity of cryopreserved allografts. Arteries were stained with hematoxylin and eosin, Masson's trichrome, and orcein for morphometric analyses and immunostained to identify endothelial cells, smooth muscle cells, T lymphocytes, and macrophages. Results. Among nonimplant arteries, cryopreservation reduced ␣-actin expression and increased the luminal area. All implanted autografts were patent. Cryopreserved autografts showed reduced ␣-actin expression and developed intimal hyperplasia compared to fresh autografts. Treatment with CsA improved the patency of fresh allografts from 0% to 83% (P Ͻ .01) and of cryopreserved allografts from 40% to 100% (P Ͻ .05). Cryopreserved allografts showed substantial intimal hyperplasia, and fresh allografts had more T lymphocyte infiltration in the intimal layer with aneurysmal dilatation. Conclusions. Cryopreservation reduces the deposition of inflammatory cells and prevents the thrombosis or aneurysmal lesions observed in fresh allografts. Therefore, cryopreservation modifies the antigenicity of vascular allografts.
Journal of the American College of Cardiology, 1998
coronary angiograms reactivity in postmenopausal women with angina pectoris and normal results on... more coronary angiograms reactivity in postmenopausal women with angina pectoris and normal results on Short-term effects of transdermal estrogen replacement therapy on coronary vascular This information is current as of July 17, 2011 http://content.onlinejacc.org the World Wide Web at:
The Journal of Heart and Lung Transplantation, 2008
European Journal of Clinical Investigation, 2003
High plasma levels of angiotensin II are found in several pathologies such as hypertension, heart... more High plasma levels of angiotensin II are found in several pathologies such as hypertension, heart failure and myocardial infarction. The effect of high concentrations of angiotensin II on coronary circulation is not well defined. The aim of the present study was to assess coronary blood flow regulation during tachycardia in the presence of elevated coronary plasma levels of angiotensin II, and the changes induced by ACE inhibition and blockade of angiotensin II and endothelin-A receptors. Left anterior coronary artery was catheterized in 38 pigs to infuse the study drugs. Saline was infused for 15 min. Then, the first atrial pacing was performed. The pigs were distributed to: Group 1 (n = 7) angiotensin II; Group 2 (n = 7) enalaprilat + angiotensin II; Group 3 (n = 9) the bradykinin B2 antagonist HOE 140 + enalaprilat + angiotensin II; Group 4 (n = 7) losartan + angiotensin II; and Group 5 (n = 8) endothelin-A receptor antagonist LU 135252 + angiotensin II. After giving these infusions, a second pacing was repeated. The increase in coronary blood flow induced by pacing with angiotensin II was reduced from 181 +/- 21% to 116 +/- 37% (P = 0.006 vs. saline). Enalaprilat, losartan and LU 135252 restored the capacity of coronary blood flow to increase during pacing (151 +/- 39%, 162 +/- 35% and 161 +/- 16%, respectively; P = NS, vs. saline), while HOE 140 abolished the effect of enalaprilat. Moderately elevated coronary concentrations of angiotensin II reduced coronary blood flow during pacing. Enalaprilat, losartan and LU 135252 restored the hyperaemic coronary flow to similar values observed with saline. The beneficial effect of ACE inhibition is mediated through an increase in bradykinin.
European Respiratory Journal, 2010
Staphylococcus aureus is one of the most common causes of nosocomial pneumonia contributing to si... more Staphylococcus aureus is one of the most common causes of nosocomial pneumonia contributing to significant morbidity and mortality. Therapeutic options for patients with methicillin-resistant S. aureus (MRSA) infection are limited. In addition, little is known about the S. aureus virulence factors that may influence the presentation and prognosis of severe lower respiratory tract infections. Animal models of severe pneumonia allow investigators to control and exclude potential confounders and to examine the influence of comorbid conditions. Therefore, these models may improve our knowledge of the intimate pathophysiological mechanisms affecting pharmacodynamics, pharmacokinetics and efficacy of therapy. So far, animal research studies on MRSA and vancomycin-resistant S. aureus, performed both in small and large animal models, have improved knowledge of the mechanisms of disease, which may lead to a better treatment for this severe and complex infection in humans.
Transplantation Proceedings, 2008
BackgroundThe aim of the present research was to study the possible interference of hemosiderin d... more BackgroundThe aim of the present research was to study the possible interference of hemosiderin deposits with the histological detection of dextran-coated, iron-labeled, mesenchymal stem cells after intracoronary administration in a porcine model of myocardial infarction.
Revista Espa de Cardiologia
The mechanisms by which estradiol dilates arterial vessels are still unclear. Our aim was to stud... more The mechanisms by which estradiol dilates arterial vessels are still unclear. Our aim was to study if estradiol enhances endothelium-dependent vasodilation in an experimental model of human arteries in vitro, and if this effect is nitric oxide mediated. Using organ bath chambers, we studied 18 arterial rings obtained from left internal mammary arteries during coronary artery bypass grafting surgery. Response to acetylcholine was evaluated at baseline and after the addition of estradiol 10-6 mol/l to the medium, both in the presence or absence of a nitric oxide synthase inhibitor (L-NNA 10-4 mol/l). Estradiol significantly enhanced the relaxation of the arterial rings in response to acetylcholine (52 +/- 20% after estradiol versus 42 +/- 22% at baseline; n = 10; p = 0.02). However, endothelium-dependent vasodilation relaxation after estradiol addition was not enhanced in the presence of L-NNA (47 +/- 25% after estradiol versus 38 +/- 22% at baseline; n = 8; p = NS). Estradiol in vitr...
P-selectin (CD62P), an adhesion molecule expressed on activated endothelial cells and platelets, ... more P-selectin (CD62P), an adhesion molecule expressed on activated endothelial cells and platelets, mediates the initial attachment of leukocytes to the stimulated endothelium upon inflammation and the interaction between leukocytes and platelets. A soluble form of P-selectin is present in the serum of healthy individuals as a circulating protein and high levels have been described in various pathological situations. The aim of this study was to characterize P-selectin on porcine platelets and investigate the soluble form of this protein, which are uncharacterized in several animal species including pigs. A new monoclonal antibody (mAb) (SwPsel.1.9) against porcine P-selectin was produced using a mouse cell line transfected with pig P-selectin cDNA. This mAb together with a previously described mAb (P-sel.KO.2.5), produced in our laboratory, was used to develop an ELISA to quantify porcine P-selectin. No significant levels of soluble-porcine P-selectin were observed in healthy animals. However, the total amount of P-selectin measured in porcine platelets was similar to that found in humans. Increased levels of this circulating protein were detected in the plasma from pigs after allograft implantation. In vitro, P-selectin expression on platelet membrane was rapidly induced by PMA and thrombin, as assessed by flow cytometry. However, these activators did not stimulate the release of soluble P-selectin. Analysis of the proteolytic cleavage of this protein from COS-transfected cells revealed that PMA treatment failed to cause the shedding of membrane-bound P-selectin. These data suggest that porcine Pselectin is a suitable marker for inflammation and that the mechanism involved in the generation of circulating P-selectin is not proteolytic release. #
Journal of The American College of Cardiology, 1998
Critical Care, 2015
Laboratory studies demonstrated that the lateral Trendelenburg position (LTP) is superior to the ... more Laboratory studies demonstrated that the lateral Trendelenburg position (LTP) is superior to the semirecumbent position (SRP) in the prevention of ventilator-associated pulmonary infections. We assessed whether the LTP could also prevent pulmonary colonization and infections caused by an endotracheal tube (ETT) biofilm. Eighteen pigs were intubated with ETTs colonized by Pseudomonas aeruginosa biofilm. Pigs were positioned in LTP and randomized to be on mechanical ventilatin (MV) up to 24 hour, 48 hour, 48 hour with acute lung injury (ALI) by oleic acid and 72 hour. Bacteriologic and microscopy studies confirmed presence of biofilm within the ETT. Upon autopsy, samples from the proximal and distal airways were excised for P.aeruginosa quantification. Ventilator-associated tracheobronchitis (VAT) was confirmed by bronchial tissue culture ≥3 log colony forming units per gram (cfu/g). In pulmonary lobes with gross findings of pneumonia, ventilator-associated pneumonia (VAP) was confirmed by lung tissue culture ≥3 log cfu/g. P.aeruginosa colonized the internal lumen of 16 out of 18 ETTs (88.89%), and a mature biofilm was consistently present. P.aeruginosa colonization did not differ among groups, and was found in 23.6% of samples from the proximal airways, and in 7.1% from the distal bronchi (P = 0.001). Animals of the 24 hour group never developed respiratory infections, whereas 20%, 60% and 25% of the animals in group 48 hour, 48 hour-ALI and 72 hour developed P.aeruginosa VAT, respectively (P = 0.327). Nevertheless, VAP never developed. Our findings imply that during the course of invasive MV up to 72 hour, an ETT P.aeruginosa biofilm hastily colonizes the respiratory tract. Yet, the LTP compartmentalizes colonization and infection within the proximal airways and VAP never develops.
European Journal of Clinical Investigation, 2000
Myocardial ischaemia and left ventricular dysfunction have been described in cocaine users. Wheth... more Myocardial ischaemia and left ventricular dysfunction have been described in cocaine users. Whether nitric oxide (NO) inhibition may potentiate the effects of cocaine on coronary circulation and ventricular function is still unknown. In order to test this hypothesis, 38 pentobarbital-anaesthetized pigs were instrumented for systolic blood pressure, coronary blood flow, left ventricular dp/dt, cardiac output, left ventricular end-diastolic and end-systolic lengths and shortening fraction. The pigs were randomized into three groups: control group: i.v. saline (n = 5); group 1: i.v. cocaine, 10 mg kg-1 over 20 min (n = 17); group 2: the same doses of cocaine 30 min after i.c. L-NAME 20 microg/kg min-1 infusion (n = 16). In order to know whether the observed effects were specific of NO inhibition, in five pigs i.c. L-arginine was simultaneously infused with L-NAME, in five pigs i.c. NTG, an endothelial-independent vasodilator, was simultaneously infused with L-NAME before cocaine was administered, and in nine additional pigs the proximal left anterior descending (LAD) flow was reduced to around 20% of the basal value by means of a mechanical occluder before cocaine was administered. Cocaine i.v did not change the coronary blood flow, while it induced a significant reduction in cardiac output, left ventricular dp/dt and shortening fraction (15 +/- 4-8 +/- 4%, P < 0.05). When cocaine was administered after L-NAME infused i.c. during 30 min, a significantly more severe reduction of the shortening fraction (12 +/- 3-4 +/- 2%, P < 0.0001) was induced; this effect was abolished by simultaneous perfusion of L-arginine i.c. NTG. The results when cocaine was administered after the 20% LAD flow reduction by mechanical occluder did not differ from those of cocaine alone. NO inhibition intensifies the cocaine-induced left ventricular dysfunction.
Journal of Cardiovascular Translational Research, 2013
Animal models that mimic human electrical and mechanical dyssynchrony often associated with chron... more Animal models that mimic human electrical and mechanical dyssynchrony often associated with chronic heart failure would provide an essential tool to investigate factors influencing response to cardiac resynchronization therapy. A standardized closed-chest porcine model of left bundle branch block (LBBB) was developed using 16 pigs. Radiofrequency applications were performed to induce LBBB, which was confirmed by QRS widening, a surface electrocardiogram pattern concordant with LBBB, and a prolonged activation time from endocardial. Echocardiography confirmed abnormal motion of the septum, which was not present at the baseline echocardiogram. High susceptibility of pigs to ventricular fibrillation during the endocardial ablation was overcome by applying high-rate pacing during radiofrequency applications. This is the first study to devise a closed-chest porcine model of LBBB that closely reproduces abnormalities found in patients with electrical and mechanical cardiac dyssynchrony, and provides a useful tool to investigate the basic mechanisms underlying cardiac resynchronization therapy benefits in heart failure.
Revista Española de Cardiología, 2000
ABSTRACT Background The role of different endothelium-derived vasoactive substances in the regula... more ABSTRACT Background The role of different endothelium-derived vasoactive substances in the regulation of coronary circulation during tachycardia is not well defined. In order to elucidate the contribution of prostacyclin to the adaptation of coronary blood flow to tachycardia, the effect of meclofenamate, a cyclooxygenase inhibitor on the coronary blood flow response to rapid atrial pacing was analyzed in a porcine model. Methods A group of seventeen pigs were instrumented for coronary blood flow, aortic pressure and atrial pacing. Heart rate was increased by 20 beats every 5 minutes. Coronary blood flow and aortic pressure were measured, and coronary resistance calculated, basally and at each pacing interval, before and after saline serum (n = 6), meclofenamate 5 mg/kg, i.v. (n = 7) or meclofenamate 35 mg/kg, i.v. (n = 4). Results Neither saline nor meclofenamate modified the normal increase of coronary blood flow provoked by rapid atrial pacing (163 ± 28% increase before versus 172 ± 29% after saline; 159 ± 21% increase before versus 161 ± 22% after meclofenamate low dosis and 201 ± 39% before vs 172 ± 36 after meclofenamate high dosis). There were no differences in the response of coronary vascular resistance to tachycardia before and after meclofenamate (44% reduction vs 40% respectively). Conclusion Cyclooxygenase blockade does not modify the response of coronary circulation to rapid atrial pacing, suggesting that prostacyclin does not play a limiting role in the regulation of coronary blood flow during tachycardia in this model.
D62. NOSOCOMIAL INFECTIONS: BACTERIOLOGY, DRUG RESISTANCE, AND OUTCOMES, 2012
B107. BACTERIAL PNEUMONIA: BIOMARKERS, RESISTANT PATHOGENS AND OUTCOMES, 2011
B107 BACTERIAL PNEUMONIA: BIOMARKERS, RESISTANT PATHOGENS AND OUTCOMES Monday, May 16/2:00 PM-4:3... more B107 BACTERIAL PNEUMONIA: BIOMARKERS, RESISTANT PATHOGENS AND OUTCOMES Monday, May 16/2:00 PM-4:30 PM / Room 401-402 (Street Level), Colorado Convention Center ... A Novel Ventilatory Strategy To Prevent Bacterial Translocation From The Oropharynx ...
B42. INVASIVE MECHANICAL VENTILATION: SOUP TO NUTS, 2010
/ Thematic Poster Session / Monday, May 17/8:15 AM-4:00 PM / B42 INVASIVE MECHANICAL VENTILATION:... more / Thematic Poster Session / Monday, May 17/8:15 AM-4:00 PM / B42 INVASIVE MECHANICAL VENTILATION: SOUP TO NUTS ... Area H, Hall G (First Level), Morial Convention Center ... Effects of Manual Rib Cage Compression On Peak Expiratory Flow And Mucus Clearance ...
Journal of Liquid Chromatography & Related Technologies - J LIQ CHROMATOGR RELAT TECHNO, 2012
Simple and specific analytical methods were developed and validated to quantify vancomycin in pla... more Simple and specific analytical methods were developed and validated to quantify vancomycin in plasma and lung tissue, which were obtained from a model of pneumonia in mechanically ventilated piglets. Tissue and plasma samples were precipitated and centrifuged; 100 µL of the supernatant were injected into the chromatographic system. Ceftazidime was used as the internal standard. The stationary phase was a silica based column Symmetry300 C18 (150 × 4.6 mm) with pre-column. The mobile phase consisted of 20% ultrafiltered water and 80% of (A) 75 mM sodium acetate buffer (pH = 3) with (B) acetonitrile (92%/8%;v/v). Isocratic flow rate was set at 0.8 mL/min and 0.7 mL/min for plasma and tissue samples, respectively. UV absorbance detection was set at 230 nm. Standard curves showed good linearity for plasma and pulmonary tissue (r > 0.99). The lower limits of quantitation were 1.56 µg/mL and 3.13 µg/mL for plasma and tissue, respectively. The intra- and inter-day precisions and accuracy...
Veterinary Immunology and Immunopathology, 2003
P-selectin (CD62P), an adhesion molecule expressed on activated endothelial cells and platelets, ... more P-selectin (CD62P), an adhesion molecule expressed on activated endothelial cells and platelets, mediates the initial attachment of leukocytes to the stimulated endothelium upon inflammation and the interaction between leukocytes and platelets. A soluble form of P-selectin is present in the serum of healthy individuals as a circulating protein and high levels have been described in various pathological situations. The aim of this study was to characterize P-selectin on porcine platelets and investigate the soluble form of this protein, which are uncharacterized in several animal species including pigs. A new monoclonal antibody (mAb) (SwPsel.1.9) against porcine P-selectin was produced using a mouse cell line transfected with pig P-selectin cDNA. This mAb together with a previously described mAb (P-sel.KO.2.5), produced in our laboratory, was used to develop an ELISA to quantify porcine P-selectin. No significant levels of soluble-porcine P-selectin were observed in healthy animals. However, the total amount of P-selectin measured in porcine platelets was similar to that found in humans. Increased levels of this circulating protein were detected in the plasma from pigs after allograft implantation. In vitro, P-selectin expression on platelet membrane was rapidly induced by PMA and thrombin, as assessed by flow cytometry. However, these activators did not stimulate the release of soluble P-selectin. Analysis of the proteolytic cleavage of this protein from COS-transfected cells revealed that PMA treatment failed to cause the shedding of membrane-bound P-selectin. These data suggest that porcine Pselectin is a suitable marker for inflammation and that the mechanism involved in the generation of circulating P-selectin is not proteolytic release. #
Transplantation Proceedings, 2008
Background. The aim of the present research was to study the possible interference of hemosiderin... more Background. The aim of the present research was to study the possible interference of hemosiderin deposits with the histological detection of dextran-coated, iron-labeled, mesenchymal stem cells after intracoronary administration in a porcine model of myocardial infarction. Materials and methods. A myocardial infarction was induced in six animals that received intracoronary iron-labeled autologous mesenchymal stem cells (group 1; n ϭ 2) or placebo (group 2; n ϭ 4). Six control animals without myocardial infarction underwent direct intramyocardial injections of iron-labeled autologous mesenchymal stem cells (group 3; n ϭ 2) or placebo (group 4; n ϭ 4). Histological sections from explanted hearts were stained with Prussian blue to identify dextran-coated, iron-labeled, mesenchymal stem cells. Results. After Prussian blue staining, granular blue labeling in the tissue was observed in both groups of animals with infarcts. Similar granular blue labeling was detected in hearts from control animals without infarction that had received iron-labeled mesenchymal stem cells. However, hearts from control animals without infarction that received placebo did not have any granular blue labeling in the tissue. Conclusions. Hemosiderin from infarction hemorrhage interferes with detection of dextran-coated iron-labeled mesenchymal stem cells after intracoronary administration, suggesting that this marker is not useful to detect mesenchymal stem cells in a porcine model of myocardial infarction.
Transplantation Proceedings, 2004
The need for arterial grafts in coronary surgery to complement autologous vessels has generated i... more The need for arterial grafts in coronary surgery to complement autologous vessels has generated interest in cryopreservation of small diameter allografts. We evaluated functional and histologic changes occurring in cryopreserved allografts 3 months after porcine femoral artery transplants. Methods. Twenty recipient and 15 donor pigs included a control group of 16 fresh and 12 cryopreserved nonimplant arteries were used. Fresh (n ϭ 5) and cryopreserved (n ϭ 5) autografts were implanted to assess cryopreservation effects in the absence of rejection. Fresh allografts with or without treatment with cyclosporine (CsA) (n ϭ 6 of 8) and cryopreserved allografts with or without treatment with CsA (n ϭ 6 of 10) were performed to study the antigenicity of cryopreserved allografts. Arteries were stained with hematoxylin and eosin, Masson's trichrome, and orcein for morphometric analyses and immunostained to identify endothelial cells, smooth muscle cells, T lymphocytes, and macrophages. Results. Among nonimplant arteries, cryopreservation reduced ␣-actin expression and increased the luminal area. All implanted autografts were patent. Cryopreserved autografts showed reduced ␣-actin expression and developed intimal hyperplasia compared to fresh autografts. Treatment with CsA improved the patency of fresh allografts from 0% to 83% (P Ͻ .01) and of cryopreserved allografts from 40% to 100% (P Ͻ .05). Cryopreserved allografts showed substantial intimal hyperplasia, and fresh allografts had more T lymphocyte infiltration in the intimal layer with aneurysmal dilatation. Conclusions. Cryopreservation reduces the deposition of inflammatory cells and prevents the thrombosis or aneurysmal lesions observed in fresh allografts. Therefore, cryopreservation modifies the antigenicity of vascular allografts.
Journal of the American College of Cardiology, 1998
coronary angiograms reactivity in postmenopausal women with angina pectoris and normal results on... more coronary angiograms reactivity in postmenopausal women with angina pectoris and normal results on Short-term effects of transdermal estrogen replacement therapy on coronary vascular This information is current as of July 17, 2011 http://content.onlinejacc.org the World Wide Web at:
The Journal of Heart and Lung Transplantation, 2008