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J D Chiche

Publications and source records attributed to J D Chiche.

At least 19 recordsLinked to original sources
PubMed2006

Changes in aortic blood flow induced by passive leg raising predict fluid responsiveness in critically ill patients.

INTRODUCTION: Esophageal Doppler provides a continuous and non-invasive estimate of descending aortic blood flow (ABF) and corrected left ventricular ejection time (LVETc). Considering passive leg raising (PLR) as a reversible volume expansion (VE), we compared the relative abilities of PLR-induced ABF variations, LVETc and respiratory pulsed pressure variations (DeltaPP) to predict fluid responsiveness. METHODS: We studied 22 critically ill patients in acute circulatory failure in the supine position, during PLR, back to the supine position and after two consecutive VEs of 250 ml of saline. Responders were defined by an increase in ABF induced by 500 ml VE of more than 15%. RESULTS: Ten patients were responders and 12 were non-responders. In responders, the increase in ABF induced by PLR was similar to that induced by a 250 ml VE (16% versus 20%; p = 0.15). A PLR-induced increase in ABF of more than 8% predicted fluid responsiveness with a sensitivity of 90% and a specificity of 83%. Corresponding positive and negative predictive values (PPV and NPV, respectively) were 82% and 91%, respectively. A DeltaPP threshold value of 12% predicted fluid responsiveness with a sensitivity of 70% and a specificity of 92%. Corresponding PPV and NPV were 87% and 78%, respectively. A LVETc of 245 ms or less predicted fluid responsiveness with a sensitivity of 70%, and a specificity of 67%. Corresponding PPV and NPV were 60% and 66%, respectively. CONCLUSION: The PLR-induced increase in ABF and a DeltaPP of more than 12% offer similar predictive values in predicting fluid responsiveness. An isolated basal LVETc value is not a reliable criterion for predicting response to fluid loading.

Aged↗
PubMed2001

Soluble guanylate cyclase alpha(1) and beta(1) gene transfer increases NO responsiveness and reduces neointima formation after balloon injury in rats via antiproliferative and antimigratory effects.

In vascular smooth muscle cells, NO stimulates the synthesis of cGMP by soluble guanylate cyclase (sGC), a heterodimer composed of alpha(1) and beta(1) subunits. NO/cGMP signal transduction affects multiple cell functions that contribute to neointima formation after vascular injury. Balloon-induced vascular injury was found to decrease sGC subunit expression and enzyme activity in rat carotid arteries. The effect of restoring sGC enzyme activity on neointima formation was investigated using recombinant adenoviruses specifying sGC alpha(1) and beta(1) subunits (Adalpha1 and Adbeta1). Coinfection of cultured rat aortic smooth muscle cells with Adalpha1 and Adbeta1 increased NO-stimulated intracellular cGMP levels 60-fold and decreased DNA synthesis and migration by 16% and 48%, respectively. Immunoreactivity for alpha(1) and beta(1) subunits colocalized in carotid arteries infected with Adalpha1 and Adbeta1. Molsidomine-stimulated carotid tissue cGMP levels were greater after coinfection with Adalpha1 and Adbeta1 than after infection with a control virus, AdRR5 (0.53+/-0.09 pmol/mg protein, mean+/-SEM, versus 0.23+/-0.09, P<0.05). Mean intima/media ratio, 2 weeks after balloon injury and twice-daily administration of 5 mg/kg molsidomine, was less in rats coinfected with Adalpha1 and Adss1 than in rats infected with AdRR5 or in uninfected rats (0.36+/-0.11 versus 0. 81+/-0.13 and 0.75+/-0.25, respectively, P<0.05). Thus, Adalpha1 and Adbeta1 gene transfer to balloon-injured rat carotid arteries increases NO responsiveness and attenuates neointima formation via a direct antiproliferative and antimigratory effect on vascular smooth muscle cells.

Angioplasty, Balloon↗
PubMed2000

Nitric oxide inhalation decreases pulmonary artery remodeling in the injured lungs of rat pups.

Vascular injury causes the muscularization of peripheral pulmonary arteries, which is more pronounced in the infant than in the adult lung. Although inhaled NO gas attenuates pulmonary artery remodeling in hypoxic rats, whether or not it protects the lung by mitigating vasoconstriction is unknown. This investigation tested whether inhaled NO decreases the muscularization of injured pulmonary arteries in rat pups by modulating vascular tone. One week after monocrotaline administration, the percentage of muscularized rat pup lung arteries was increased by >3-fold. Nevertheless, monocrotaline exposure did not cause right ventricular hypertrophy, pulmonary hypertension, or vasoconstriction. In addition, it did not increase the expression of markers of inflammation (interleukin-1beta, intercellular adhesion molecule-1, and E-selectin) or of platelet-mediated thrombosis (GPIbalpha). Continuous inhalation of 20 ppm NO gas prevented the neomuscularization of the pulmonary arteries in pups with lung injury. Moreover, a 3-fold increase in cell proliferation and 30% decrease in cell numbers in pulmonary arteries caused by monocrotaline exposure was prevented by NO inhalation. These data indicate that inhaled NO protects infants against pulmonary remodeling induced by lung injury by mechanisms that are independent of pulmonary tone, inflammation, or thrombosis.

Administration, Inhalation↗
PubMed2000

Sp110 localizes to the PML-Sp100 nuclear body and may function as a nuclear hormone receptor transcriptional coactivator.

The nuclear body is a multiprotein complex that may have a role in the regulation of gene transcription. This structure is disrupted in a variety of human disorders including acute promyelocytic leukemia and viral infections, suggesting that alterations in the nuclear body may have an important role in the pathogenesis of these diseases. In this study, we identified a cDNA encoding a leukocyte-specific nuclear body component designated Sp110. The N-terminal portion of Sp110 was homologous to two previously characterized components of the nuclear body (Sp100 and Sp140). The C-terminal region of Sp110 was homologous to the transcription intermediary factor 1 (TIF1) family of proteins. High levels of Sp110 mRNA were detected in human peripheral blood leukocytes and spleen but not in other tissues. The levels of Sp110 mRNA and protein in the human promyelocytic leukemia cell line NB4 increased following treatment with all-trans retinoic acid (ATRA), and Sp110 localized to PML-Sp100 nuclear bodies in ATRA-treated NB4 cells. Because of the structural similarities between Sp110 and TIF1 proteins, the effect of Sp110 on gene transcription was examined. An Sp110 DNA-binding domain fusion protein activated transcription of a reporter gene in transfected mammalian cells. In addition, Sp110 produced a marked increase in ATRA-mediated expression of a reporter gene containing a retinoic acid response element. Taken together, the results of this study demonstrate that Sp110 is a member of the Sp100/Sp140 family of nuclear body components and that Sp110 may function as a nuclear hormone receptor transcriptional coactivator. The predominant expression of Sp110 in leukocytes and the enhanced expression of Sp110 in NB4 cells treated with ATRA raise the possibility that Sp110 has a role in inducing differentiation of myeloid cells.

Amino Acid Sequence↗
PubMed2000

Partial liquid ventilation ventilates better than gas ventilation.

Partial liquid ventilation (PLV) improves oxygenation in several models of lung injury. However, PLV has only been compared with conventional gas ventilation (GV) with low PEEP. Both PLV and GV can markedly improve oxygenation when PEEP is set above the lower corner pressure (Plc) on the inspiratory pressure-volume (P-V) curve of the total respiratory system. We questioned if the use of PEEP set above the Plc during PLV and GV would result in similar gas exchange. Lung injury was induced in 12 sheep by saline lavage before randomization to PLV (n = 6) or GV (n = 6). Animals in the PLV group were filled with perflubron (22 ml/kg) until a meniscus at the teeth was observed. Both groups were then ventilated with pressure control (FI(O(2)), 1.0; rate, 20/min; I:E, 1:1) and PEEP (1 cm H(2)O above the Plc on the inspiratory P-V curve). Peak inspiratory pressure (PIP) was limited to 35 cm H(2)O. Animals were ventilated for 5 h and then killed for histologic examinations. All 12 animals survived the 5-h ventilation period. After increasing PEEP above Plc, Pa(O(2)) increased significantly (p < 0.01) in both the GV and the PLV groups, but it did not differ significantly between groups (p = 0.86) at any time during the experiment. Pa(CO(2)) and VD/VT in GV increased markedly throughout the experiment after increasing PEEP (p < 0.001), but there was no significant change in Pa(CO(2)) in PLV (p = 0.13). Mean arterial blood pressure, mean pulmonary artery pressure, pulmonary artery occlusion pressure, and central venous pressure, increased and SVR decreased in GV (p < 0.05). The extent and the severity of lung injury in the dependent regions was greater in the GV group (p < 0.05). Both PLV and GV improved oxygenation, but PLV resulted in better ventilation than GV while preserving lung structure when PEEP was set 1 cm H(2)O above the Plc and PIP limited to 35 cm H(2)O.

Animals↗
PubMed1999

Structural and functional heterogeneity of nuclear bodies.

The nuclear body is a cellular structure that appears to be involved in the pathogenesis of acute promyelocytic leukemia and viral infection. In addition, the nuclear body is a target of autoantibodies in patients with the autoimmune disease primary biliary cirrhosis. Although the precise function of the nuclear body in normal cellular biology is unknown, this structure may have a role in the regulation of gene transcription. In a previous investigation, we identified a leukocyte-specific, gamma interferon (IFN-gamma)-inducible autoantigen designated Sp140. The objectives of the present study were to investigate the cellular location of Sp140 with respect to the nuclear-body components PML and Sp100 and to examine the potential role of Sp140 in the regulation of gene transcription. We used adenovirus-mediated gene transfer to express Sp140 in human cells and observed that the protein colocalized with PML and Sp100 in resting cells and associated with structures containing PML during mitosis. In cells infected with the adenovirus expressing Sp140 and incubated with IFN-gamma, the number of PML-Sp100 nuclear bodies per cell increased but immunoreactive Sp140 was not evenly distributed among the nuclear bodies. Sp140 associated with a subset of IFN-gamma-induced PML-Sp100 nuclear bodies. To examine the potential effect of Sp140 on gene transcription, a plasmid encoding Sp140 fused to the DNA-binding domain of GAL4 was cotransfected into COS cells with a chloramphenicol acetyltransferase (CAT) reporter gene containing five GAL4-binding sites and a simian virus 40 enhancer region. The GAL4-Sp140 fusion protein increased the expression of the reporter gene. In contrast, Sp100 fused to the GAL4 DNA-binding domain inhibited CAT activity in transfected mammalian cells. The results of this study demonstrate that Sp140 associates with a subset of PML-Sp100 nuclear bodies in IFN-gamma-treated cells and that Sp140 may activate gene transcription. Taken together, these observations suggest that the nuclear bodies within a cell may be heterogeneous with respect to both composition and function.

Adenoviridae↗
PubMed1999

Effects of dobutamine on gastric mucosal perfusion and hepatic metabolism in patients with septic shock.

We prospectively evaluated the effects of dobutamine on gastric mucosal perfusion and hepatocytic clearance in patients with septic shock. After resuscitation with volume expansion and norepinephrine (12 patients) as needed, 14 hemodynamically stable patients (median age: 60 yr, median SAPS II score: 47) were given an infusion of 7.5 microg/kg/min dobutamine for 1 h. Gastric mucosal perfusion and hepatocytic clearance were assessed with tonometry and indocyanine green (ICG) elimination, respectively. All measurements were made before dobutamine infusion, after 1 h of dobutamine infusion, and 1 h after the infusion ended. Cardiac output (thermodilution technique) increased with dobutamine from a baseline median level of 4.0 L/min/m(2) (range: 1.7 to 7.4 L/min/m(2)) to 5.0 L/min/m(2) (range: 3.5 to 8.9 L/min/m(2)) (p = 0.004) and returned to baseline levels after dobutamine infusion ended. The gastric-arterial PCO(2) difference decreased from a baseline median level of 13 mm Hg (range: 5 to 54 mm Hg) to 7 mm Hg (range: 5 to 48 mm Hg) (p = 0.005). ICG elimination was low in all patients at baseline (median plasma disappearance rate: 12.2%; range: 7.6 to 16.2%) and did not change significantly during or after dobutamine infusion. In summary, dobutamine increases gastric mucosal perfusion but does not alter hepatocytic clearance in patients with septic shock. The absence of a beneficial effect of dobutamine on hepatocytic clearance may be related to profound alterations in hepatocellular metabolism during septic shock.

Adult↗
PubMed1998

Adenovirus-mediated gene transfer of cGMP-dependent protein kinase increases the sensitivity of cultured vascular smooth muscle cells to the antiproliferative and pro-apoptotic effects of nitric oxide/cGMP.

Studies in vitro have underestimated the importance of cGMP-dependent protein kinase (PKG) in the modulation of vascular smooth muscle cell (SMC) proliferation and apoptosis in vivo. This is attributable, in part, to a rapid decline in PKG levels as vascular SMC are passaged in culture. We used a recombinant adenovirus encoding PKG (Ad.PKG) to augment kinase activity in cultured rat pulmonary artery SMC (RPaSMC). Incubation of Ad. PKG-infected RPaSMC (multiplicity of infection = 200) with 8-Br-cGMP decreased serum-stimulated DNA synthesis by 85% and cell proliferation at day 5 by 74%. The effect of 8-Br-cGMP on DNA synthesis in Ad.PKG-infected RPaSMC was blocked by KT5823 (PKG inhibitor), but not by KT5720 (cAMP-dependent protein kinase inhibitor). A nitric oxide (NO) donor compound, S-nitrosoglutathione, at concentrations as low as 100 nM, inhibited DNA synthesis in Ad. PKG-infected RPaSMC, but not in uninfected cells or in cells infected with a control adenovirus. In addition, 8-Br-cGMP and S-nitrosoglutathione induced apoptosis in serum-deprived RPaSMC infected with Ad.PKG, but not in uninfected cells or in cells infected with a control adenovirus. These results demonstrate that modulation of PKG levels in vascular SMC can alter the sensitivity of these cells to NO and cGMP. Moreover, these observations suggest an important role for PKG in the regulation of vascular SMC proliferation and apoptosis by NO and cGMP.

Adenoviridae↗
PubMed1998

Hemodynamic changes induced by laparoscopy and their endocrine correlates: effects of clonidine.

OBJECTIVES: We investigated endocrine correlates of the hemodynamic changes induced by carbon dioxide pneumoperitoneum (PNO). We then studied whether clonidine might modulate the hemodynamic changes induced by PNO by reducing release of catecholamines and vasopressin. BACKGROUND: Both mechanical and neurohumoral factors contribute to the hemodynamic changes induced by carbon dioxide PNO. Several mediators have been proposed, but no study has correlated hemodynamic changes with changes in levels of these potential mediators. METHODS: We conducted two studies, each including 20 healthy patients scheduled for elective laparoscopic cholecystectomy. In the first study serial measurements of hemodynamics (thermodilution technique) were done during laparoscopy and after exsufflation. Plasma concentrations of cortisol, catecholamines, vasopressin, renin, endothelin and prostaglandins were measured at the same time points. In the second study patients were randomly allocated to receive 8 microg/kg clonidine infused over 1 h or placebo before PNO. Hemodynamics and plasma levels of cortisol, catecholamines and vasopressin were measured during PNO and after exsufflation. RESULTS: Peritoneal insufflation resulted in a significant reduction of cardiac output (18+/-4%) and increases in mean arterial pressure (39+/-8%) and systemic (70+/-12%) and pulmonary (98+/-18%) vascular resistances. Laparoscopy resulted in progressive and significant increases in plasma concentrations of cortisol, epinephrine, norepinephrine and renin. Vasopressin plasma concentrations markedly increased immediately after the beginning of PNO (before PNO 6+/-4 pg/ml; during PNO 129+/-42 pg/ml; p < 0.05). The profile of vasopressin release paralleled the time course of changes in systemic vascular resistance. Prostaglandins and endothelin did not change significantly. Clonidine significantly reduced mean arterial pressure, heart rate and the increase in systemic vascular resistance. Clonidine also significantly reduced catecholamine concentrations but did not alter vasopressin and cortisol plasma concentrations. CONCLUSIONS: Vasopressin and catecholamines probably mediate the increase in systemic vascular resistance observed during PNO. Clonidine before PNO reduces catecholamine release and attenuates hemodynamic changes during laparoscopy.

Adrenergic alpha-Agonists↗
PubMed1997

Effect of bi-level positive airway pressure (BiPAP) nasal ventilation on the postoperative pulmonary restrictive syndrome in obese patients undergoing gastroplasty.

STUDY OBJECTIVE: Upper abdominal surgery results in a postoperative restrictive pulmonary syndrome. Bi-level positive airway pressure (BiPAP System; Respironics Inc; Murrysville, Pa), which combines pressure support ventilation and positive end-expiratory pressure via a nasal mask, could allow alveolar recruitment during inspiration and prevent expiratory alveolar collapse, and therefore limit the postoperative pulmonary restrictive syndrome. This study investigated the effect of BiPAP on postoperative pulmonary function in obese patients after gastroplasty. DESIGN: Prospective controlled randomized study. SETTING: GI surgical ward in a university hospital. PATIENTS: Thirty-three morbidly obese patients scheduled for gastroplasty were studied. INTERVENTION: The patients were assigned to one of three techniques of ventilatory support during the first 24 h postoperatively: O2 via a face mask, BiPAP System 8/4, with inspiratory and expiratory positive airway pressure set at 8 and 4 cm H2O, respectively, or BiPAP System 12/4 set at 12 and 4 cm H2O. Pulmonary function (FVC, FEV1, and peak expiratory flow rate [PEFR]) were measured the day before surgery, 24 h after surgery, and on days 2 and 3. Oxygen saturation by pulse oximeter (SpO2) was also recorded during room air breathing. RESULTS: Three patients were excluded. After surgery, FVC, FEV1, PEFR, and SpO2 significantly decreased in the three groups. On day 1, FVC and FEV1 were significantly improved in the group BiPAP System 12/4, as compared with no BiPAP; SpO2 was also significantly improved. After removal of BiPAP System 12/4, these benefits were maintained, allowing faster recovery of pulmonary function. No significant effects were observed on PEFR. BiPAP System 8/4 had no significant effect on the postoperative pulmonary restrictive syndrome. CONCLUSION: Prophylactic use of BiPAP System 12/4 during the first 24 h postoperatively significantly reduces pulmonary dysfunction after gastroplasty in obese patients and accelerates reestablishment of preoperative pulmonary function.

Adult↗
PubMed1996

Laparoscopic-assisted colectomy in heart transplant recipients.

Reports of laparoscopy in heart graft recipients are scarce and, to our knowledge, laparoscopic colectomy has not yet been reported in heart transplant patients. The magnitude and the tolerance of the hemodynamic changes induced by pneumoperitoneum are unknown in heart graft recipients, who have a denervated heart and are "preload-dependent". The authors report the clinical courses of 2 heart graft recipients who developed acute diverticulitis without perforation or peritonitis and who underwent laparoscopic-assisted colectomy without complications.

Abscess↗
PubMed1995

Inhaled nitric oxide for hemodynamic support after postpneumonectomy ARDS.

Inhaled nitric oxide (NO) has been reported to promote selective pulmonary vasodilation and better arterial oxygenation in cases of adult respiratory distress syndrome (ARDS) with pulmonary hypertension (PHT). However, the clinical relevance of these changes and their effects on outcome remain to be proven, since long-term inhalation carries a potential risk of toxicity. We used NO to treat a patient who developed postpneumonectomy ARDS with severe PHT and right ventricular failure. NO resulted in better oxygenation and markedly improved hemodynamic status. As the underlying disease progressively worsened the patient became fully dependent on NO for hemodynamic support, and he died after 24 days of effective supportive therapy with inhaled NO.

Administration, Inhalation↗
PubMed1995

Pneumothorax during laparoscopic fundoplication: diagnosis and treatment with positive end-expiratory pressure.

Pneumothorax can develop during laparoscopy, particularly during laparoscopic fundoplication, since the left parietal pleura is exposed and can be torn during dissection in the diaphragmatic hiatus. Such an event will result in specific pathophysiologic changes, since CO2, under pressure in the abdominal cavity, will pass into the pleural space. The aim of this study was to document the pathophysiologic changes induced by pneumothorax, and to evaluate the benefit of positive end-expiratory pressure (PEEP) to treat pneumothorax. Forty-six ASA physical status I and II patients scheduled for laparoscopic fundoplication were monitored extensively; heart rate, mean arterial pressure, end-tidal CO2 (PETCO2), oxygen saturation of hemoglobin (Spo2), minute ventilation, tidal volume, dynamic total lung thorax compliance, and airway pressures were recorded. In 25 patients, oxygen uptake, CO2 elimination and arterial blood gases were also measured. Pneumothorax was diagnosed in seven patients. It resulted in the following pathophysiologic changes: decrease in total lung thorax compliance, increase in airway pressures, and increase in CO2 absorption. Consequently, PACO2 and PETCO2 also increased. Spo2, however, remained normal. The use of PEEP largely corrected these respiratory changes. None of these pneumothoraces required drainage. These data suggest that pneumothorax is common during laparoscopic fundoplication. Early diagnosis is possible by simultaneous monitoring of PETCO2, total lung thorax compliance, and airway pressures. Finally, treatment with PEEP provides an alternative to chest tube placement when pneumothorax is secondary to passage of peritoneal CO2 into the interpleural space.

Adult↗
PubMed1991

Hemodialysis for acute renal failure in patients with hematologic malignancies.

OBJECTIVE: To assess the prognosis of patients with hematologic malignancies in acute renal failure who require hemodialysis. DESIGN: Retrospective study. SETTING: ICU. PATIENTS: Forty-three consecutive patients. METHODS: Prognostic analysis using both univariate and multivariate (stepwise regression) methods. RESULTS: Fifteen (35%) patients recovered from acute renal failure and 12 (28%) were discharged from the ICU. The prognosis of patients with acute renal failure linked to sepsis is poorer than the prognosis of the patients with acute renal failure from other etiologies. Only one patient survived in the former group (n = 26) and 11 in the latter group (n = 17); p less than .0001 in multivariate analysis. When accompanied by associated respiratory failure, mortality rate was higher (93% vs. 33%; p less than .0001). The Simplified Acute Physiology Score (SAPS) calculated within the first 24 hr of admission was significantly (p less than .001) related to mortality when the SAPS was greater than or equal to 13. The presence of neutropenia and the type of hematologic malignancy were not related to a worse prognosis. Tolerance to hemodialysis appeared good, and complications were rare.

Acute Kidney Injury↗