Periodontopathogens antibodies and major adverse events following an acute myocardial infarction: results from the French Registry of Acute ST-Elevation and Non-ST-Elevation Myocardial Infarction (FAST-MI).

BACKGROUND: Periodontopathogens antibodies have been shown to be associated with primary myocardial events, but little is known regarding their impact on major adverse events after a prior acute myocardial infarction (AMI). The present prospective study evaluates the association between antibody levels of 4 periodontopathogens and the risk of all-cause death or non-fatal myocardial infarction (MI) at 1 year in 975 patients admitted for acute ST segment or non-ST segment elevation MI in French Registry of Acute ST-Elevation and Non-ST-Elevation Myocardial Infarction (FAST-MI), a nationwide French survey. METHODS: Multiserotype ELISAs were performed to assess levels of IgG and IgA against Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia and Tannerella forsythia. RESULTS: Adjusted HRs indicate the lack of association between IgG-anti-Po. gingivalis levels (0.96 (0.78 to 1.18)), IgA-anti-Po. gingivalis levels (1.13 (0.90 to 1.42)) and the risk of all-cause death or non-fatal MI at 1 year. Additionally, no significant association was found between the occurence of an event at 1 year and immunoglobulins levels against the others periodontopathogens. CONCLUSIONS: The present data indicate that circulating levels of periodontopathogens antibodies are not associated with an increased risk of major adverse events in patients with a prior AMI. Studies dealing with bacterial and clinical data are needed to assess the role of oral health in comprehensive cardiac rehabilitation programmes.

Common SNPs of AmelogeninX (AMELX) and dental caries susceptibility.

Genetic approaches have shown that several genes could modify caries susceptibility; AmelogeninX (AMELX) has been repeatedly designated. Here, we hypothesized that AMELX mutations resulting in discrete changes of enamel microstructure may be found in children with a severe caries phenotype. In parallel, possible AMELX mutations that could explain resistance to caries may be found in caries-free patients. In this study, coding exons of AMELX and exon-intron boundaries were sequenced in 399 individuals with extensive caries (250) or caries-free (149) individuals from nine French hospital groups. No mutation responsible for a direct change of amelogenin function was identified. Seven single-nucleotide polymorphisms (SNPs) were found, 3 presenting a high allele frequency, and 1 being detected for the first time. Three SNPs were located in coding regions, 2 of them being non-synonymous. Both evolutionary and statistical analyses showed that none of these SNPs was associated with caries susceptibility, suggesting that AMELX is not a gene candidate in our studied population.

Preoperative plasma B-type natriuretic peptide (BNP) identifies abnormal transthoracic echocardiography in elderly patients with traumatic hip fracture.

INTRODUCTION: This prospective study was designed to evaluate whether preoperative plasma brain natriuretic peptide (BNP) could identify significant preoperative cardiovascular disease in elderly hip-fractured patients. PATIENTS AND METHODS: Preoperative plasma BNP measurement and rest transthoracic echocardiography (TTE) were performed within 24 h after admission in consecutive hip-fractured patients aged ≥65 years. The major echocardiographic abnormality (MEA) group included patients with at least one TTE abnormality, defined as systolic pulmonary artery pressure (PAP(s)) ≥50 mmHg, left ventricular (LV) systolic dysfunction, increased LV filling pressure (LVFP) or severe valvular disease. The control group included the remaining patients. RESULTS: Seventy-five patients (mean±SD (range) age=85±5 (69-97) years) were included during a 6-month period. Twenty-four (32%) patients constituted the MEA group (17 elevated PAP(s), three LV systolic dysfunctions, 10 increased LVFP, one severe aortic stenosis and one severe mitral regurgitation). Median (interquartile) preoperative BNP value was significantly greater in MEA than in the control group (527 (361) vs. 119 (154) pg ml(-1); p<0.0001). A preoperative plasma BNP cut-off value at 285 pg ml(-1) predicted well MEA with an area under the receiver operating characteristic (ROC) curve equal to 0.895 (p<0.0001) and with a hazard ratio (HR) (confidence interval, CI) of 23.8 (3.7-142.9) (p=0.0008) on multivariate analysis. The presence of MEA or BNP≥285 pg ml(-1) was associated with high mortality. DISCUSSION: The incidence of echocardiographic signs of elevated PAP(s) or elevated LVFP in elderly hip-fractured patients was high. A preoperative BNP value ≥285 pg ml(-1) can discriminate between elderly hip-fractured patients with or without MEA.

Assessment of topographic brachial plexus nerves variations at the axilla using ultrasonography.

BACKGROUND: The aim of this study was to describe topographic variations in the arrangement of the four main brachial plexus nerves at the junction of the axilla and the upper part of the arm. METHODS: In 153 patients undergoing upper arm surgery using axillary block, we studied nerve arrangements with a three-step approach, combining: (A) cross-sectional ultrasound imaging using a 12 MHz linear ultrasound probe; (B) distal shift of the ultrasound scanhead from the axilla to the elbow joint following the paths of individual nerves; and (C) identifying the distal motor response to electrical nerve stimulation of each nerve. These results were then converted into a 12-section pie chart with the axillary artery (AA) as the axis. RESULTS: The order of the nerves around the AA was median, ulnar, radial, and musculocutaneous in all cases. The most frequent arrangement was observed in 65% of the patients. Five less frequent variations were observed in 4-20% of the patients, with four other variations seen in <2% of the patients. In 78% of the cases, the four nerves were seen separately using static ultrasound imaging. The musculocutaneous nerve was close to the artery in 18% of the patients. CONCLUSIONS: Topographic variations of the four main nerves at the axilla were found to be numerous, the most frequent arrangement being seen in less than two-thirds of the patients. Four separate nerves were seen on static ultrasound imaging at this sectional level of the axilla in only 78% of the cases.

[Pseudomonas aeruginosa epidemiology in intensive care units: importance of cross-transmission]. / Importance de la transmission croisée dans l'épidémiologie de Pseudomonas aeruginosa en service de soins intensifs.

OBJECTIVES: To update the local epidemiological data of Pseudomonas aeruginosa in intensive care units (ICU) by assessing the colonisation incidence rate and the level of cross-transmission. METHODS: Study carried out in both adult ICUs of the university-hospital of Besançon during a 2 years period. Clinical and surveillance specimens were screened for P. aeruginosa. Pulsed-field-gel-electrophoresis was used as genotyping method to evaluate the rate of cross-transmission. RESULTS: During the study, 314 patients were positive for P. aeruginosa (incidence rate of 19.1 patients per 100 admitted patients). One hundred sixty-six of these patients were detected with a clinical specimen and 148 with a screening specimen. Seventy-seven patients were colonised upon admission in the intensive care unit and 237, negative on admission, became positive during their stay. Of the ICU-acquired cases, the mean length of stay before P. aeruginosa colonisation was acquired was 15.7 days. Genotyping revealed that 53.5% of P. aeruginosa colonisation was acquired via cross-transmission (respectively 48.1% in the medical ICU and 59.2% in the surgical ICU); the other cases probably originated from endogenous sources. CONCLUSION: The incidences of P. aeruginosa colonisation upon admission and during hospitalisation are consistent with other french and european studies. Although we probably over-estimated the rate of cross-transmission, our results demonstrate that cross-transmission may be a major cause of P. aeruginosa dissemination in ICUs.

Endemicity, molecular diversity and colonisation routes of Pseudomonas aeruginosa in intensive care units.

OBJECTIVE: We carried out a prospective study to evaluate the endemicity of Pseudomonas aeruginosa in intensive care units (ICUs). Pulsed-field gel electrophoresis (PFGE) was used to determine the genotypes of P. aeruginosa isolates. This allowed us to determine the importance of cross-colonisation and the colonisation routes of P. aeruginosa. DESIGN: We screened epidemiological specimens (rectal swab, nose swab and tracheal aspiration) and routine clinical cultures from patients admitted to ICUs during a 2-year period, from 1st January, 1998, to 31st December, 1999. SETTING: The study was carried out in four separate adult ICUs located in the Franche-Comté region of France. These four units admitted a total of 1,500 patients per year. RESULTS: A total of 1686 specimens were collected from 473 patients; 122 of these patients were positive on admission, 351 became positive during hospitalisation. The overall incidence of P. aeruginosa was 15.7 cases per 100 patients and 15.1 cases per 1000 days of hospitalisation. Of 184 patients with at least one ICU-acquired positive clinical culture, 104 had been previously identified as carriers by a similar genotype. Typing of 208 non-replicate isolates revealed 101 major DNA patterns. Approximately 50% of P. aeruginosa carriage or colonisation/infection was acquired via cross-transmission; the other cases probably originated from endogenous sources. CONCLUSION: Cross-colonisation seems to play an important role in the general spread of P. aeruginosa in ICUs.

Large outbreak in a surgical intensive care unit of colonization or infection with Pseudomonas aeruginosa that overexpressed an active efflux pump.

During a 30-month survey, 55 patients were colonized or infected by a single clone of Pseudomonas aeruginosa in a surgical intensive care unit (ICU). This clone overexpressed an efflux pump system, and its antibiotic resistance pattern was extremely stable as it spread from patient to patient. Pulsed-field gel electrophoresis showed that isolates from different patients were genetically identical or very similar. We were unable to identify an environmental reservoir, but cultures of hand specimens from 2 health care workers were positive. It was not clear whether this carriage was the source of the epidemic or a consequence of it. However, the propagation of the epidemic clone was probably linked to its transmission by the staff from patient to patient. The outbreak was controlled, with difficulty, by strengthening isolation procedures, replacing the antiseptic soap being used by the staff, and changing the antibiotic prescription policy. This observation emphasizes the importance of compliance with hand washing and universal precautions.

[Severe obstetric complications nescessitating hospitalization and intensive care: a ten year retrospective study]. / Complications obstétricales graves nécessitant une hospitalisation en réanimation: étude rétrospective sur 10 ans au CHU de Besançon.

OBJECTIVES: To assess the serious maternal morbidity during pregnancy, delivery and post partum, which led to an hospitalization in a medical or surgical intensive care unit. STUDY DESIGN: A Retrospective study was carried out on a period of ten years, from July 1986 to July 1996, in the University Teaching Hospital of Besançon. PATIENTS: The criterions of inclusion come from the definition of the serious maternal morbidity decided by the Inserm: any admission of a pregnant woman in a medical or surgical intensive care unit in the 42 days of the post-partum, whatever the term of the pregnancy and the type of the post-partum, extra uterine pregnancy, spontaneous miscarriage and medical or voluntary abortion. METHODS: Forty-six patient's medical file hospitalized in a medical or surgical intensive care unit between July, 1st 1986 and July, 31st 1996, have been studied. RESULTS: The analysis of the cause underline the gravity of the pathologies handled with young patients and initially healthy, the short length of controlled ventilation and hospitalization, the avoidability of great number of transfer in an intensive care unit, and the lack of hospitalization due to anaesthesia. The frequency of hospitalisation in an intensive care unit during and after the pregnancy was estimated at 0.17% of lives births. CONCLUSION: The serious maternal morbidity could be an indicator of the quality of the obstetrics cares which would complete the study of the maternal mortality. The potential gravity of the complication of the pregnancy and the delivery require better care of this patients.

Does halothane or isoflurane affect hypoxic and post-hypoxic vascular response in rabbit aorta?

BACKGROUND: Halothane and isoflurane affect differently endothelium-dependent and -independent vasorelaxation at 95% O2. In addition, hypoxic vascular response might involve endothelium-dependent and -independent mechanisms. Therefore, we investigated, in rabbit aortic rings, 1) the influence of halothane and isoflurane on vasodilation at 95% O2 and on hypoxic-induced vasorelaxation at 0% O2 and 2) the influence of halothane and isoflurane on endothelium-dependent and -independent post-hypoxic vascular response. METHODS: Endothelium-intact and endothelium-denuded rabbit aortic rings were used. Phenylephrine precontracted rings were exposed, at 95% O2, to acetylcholine (ACh, 10(-9) to 10(-4) M) or sodium nitroprusside (SNP, 10(-9) to 10(-4) M) in the presence or absence of anaesthetic at 1 or 2 MAC. Precontracted rings were also exposed to an acute reduction in O2 from 95% to 0% followed by an acute reoxygenation with 95% O2 in the absence or presence of anaesthetic at 1 or 2 MAC. RESULTS: At 95% O2, halothane decreased endothelium-dependent relaxation to ACh, while endothelium-independent relaxation to SNP was decreased only at 2 MAC. Isoflurane did not modify ACh- or SNP-induced relaxation. At 0% O2, neither halothane nor isoflurane altered the hypoxic vascular relaxation. Post-hypoxic response was not changed either. CONCLUSION: Our results indicate that halothane and isoflurane do not alter vascular hypoxic response in conductance arteries.

[Effects of anesthetic agents on arterial reactivity]. / Effets des agents anesthésiques sur la vasomotricité artérielle.

OBJECTIVE: To review the effects of halogenated and intravenous anaesthetics on arterial vasoreactivity. DATA SOURCE: Articles were obtained from a MEDLINE review (search terms: 'vascular smooth muscle, endothelium' used separately or associated with following anaesthetic agents: 'halothane, isoflurane, enflurane, desflurane, sevoflurane, thiopentone, propofol, ketamine, etomidate'. Other sources included review articles and textbooks. STUDY SELECTION AND DATA EXTRACTION: All experimental studies published since 1975 were analysed and pertinent data extracted. DATA SYNTHESIS: Within the vascular wall, arterial vasoreactivity involves the endothelium and the vascular smooth muscle. In vivo, arterial vasoreactivity is regulated by neuronal, hormonal, and metabolic factors. In vitro, the direct action of anaesthetic agents on the vessel can be studied in the absence of such factors. In vitro studies with arterial rings have shown that inhalational anaesthetics directly decrease endothelium-independent contraction induced by various pharmacological agents. This direct effect of anaesthetics results from a decrease in intracellular calcium, mainly caused by an inhibition of transsarcoplasmic calcium influx. Volatile anaesthetics decrease endothelium-dependent vasorelaxation at a site(s) within the nitric oxide (NO) signalling pathway, located downstream from the NO-related receptors and upstream from guanylyl cyclase. They may also decrease endothelium-independent vasorelaxation by inhibiting NO activation of guanylate cyclase. Intravenous anaesthetics, such as propofol, barbiturates, ketamine and etomidate also decrease vasoconstriction by various degrees. Propofol is the most potent inhibitor of vasoconstriction and thiopental the least one. All these IV anaesthetics have been shown to inhibit in some circumstances both endothelium-dependent and -independent vasorelaxation. Further studies are required to enable a better understanding of the mechanism and the site of action of these vascular effects of anaesthetics. For example, the investigation of the effects of anaesthetic agents on vascular reactivity in diseases associated with endothelial dysfunction may indirectly provide insight into the role of endothelium.

Effects of propofol on vascular reactivity in isolated aortae from normotensive and spontaneously hypertensive rats.

We have investigated the effects of propofol 50 mumol litre-1 on contractile and relaxant responses in experimental hypertension and assessed endothelial modulation of these responses. Propofol attenuated norepinephrine-induced contraction of endothelium-intact and endothelium-denuded rings from both Wistar Tokyo (WKY) and spontaneously hypertensive rats (SHR). The effect was significantly greater in endothelium-intact aortae from SHR than in those from WKY rats. Propofol markedly attenuated AVP-induced contraction in aortae from both WKY and SHR. Propofol attenuation of norepinephrine contraction was also observed in rings from both SHR and WKY rats incubated with L-NAME. Propofol attenuation of norepinephrine contraction was suppressed by indomethacin in aortae from SHR but not in those from WKY rats. These results suggest that: (1) propofol attenuated vascular contraction of isolated aortae from SHR in part by a mechanism dependent on events distal to the receptor site (norepinephrine, arginine vasopressin); (2) the effect of propofol on contraction in SHR, observed in the presence of nitric oxide synthase inhibitors but not cyclooxygenase inhibitors, was consistent with either propofol induction of vasodilating cyclooxygenase metabolites from the endothelium or propofol inhibition of vasoconstricting cyclooxygenase metabolites.

Removal of piperacillin in critically ill patients undergoing continuous venovenous hemofiltration.

OBJECTIVE: Continuous hemofiltration is now widely used in the intensive care unit. Our study aimed to assess the removal of piperacillin under continuous hemofiltration and to define a suitable dosage regimen of administration. DESIGN: Prospective study of blood and ultrafiltrate concentrations of piperacillin to assess the pharmacokinetics of the antibiotic. SETTING: The medical intensive care unit of a teaching hospital. PATIENTS: Ten patients were included in the study. Six patients were receiving their first dose of piperacillin (group 1) and four had already been treated for 2 to 6 days (group 2). The mean Simplified Acute Physiology II score was 74 +/- 6 (SEM), and the number of organ failures was 3.6 +/- 0.3 (range 3 to 5). Renal failure was related to septic shock in seven patients and to cardiogenic shock in three patients. Seven patients were anuric. Hepatic dysfunction was present in four of the ten patients. INTERVENTIONS: Patients were treated with continuous venovenous hemofiltration using a hollow polysulfone capillary fiber. Piperacillin (4 g) was injected intravenously over 20 mins. Arterial blood and ultrafiltrate were sampled immediately before the injection and then every hour until 8 hrs after injection time. Piperacillin concentrations were assayed using high performance liquid chromatography. MEASUREMENTS AND MAIN RESULTS: In group 1, the mean serum peak concentration of piperacillin was in the normal range (125 +/- 21 mg/L), but trough values were higher (48 +/- 8 mg/L) than in normal subjects. In group 2, trough values before the injection were increased in all patients (188 +/- 71 mg/L). At T1, blood peak concentration reached 470 +/- 127 mg/L. A small amount of piperacillin was retrieved from the ultrafiltrate. The elimination half-life was 5.1 +/- 1.4 and 4.8 +/- 1.4 hrs in groups 1 and 2, respectively. CONCLUSIONS: Piperacillin was not removed to a significant extent during continuous hemofiltration. Further, in the intensive care unit, patients in shock with multiple organ failure such as liver failure might behave differently from patients with stable end-stage renal disease. A 4-g dose of piperacillin twice a day is recommended in such patients.

Myocardial and vascular adrenergic alterations in a rat model of endotoxin shock: reversal by an anti-tumor necrosis factor-alpha monoclonal antibody.

OBJECTIVES: a) To investigate responsiveness to exogenous catecholamines in rat endotoxin shock by studying both myocardial and vascular functional parameters, and to determine the relationship of these parameters with other relevant biological parameters of the adrenergic pathway, such as myocardial beta-adrenergic receptors and cyclic adenosine monophosphate (cAMP); b) to investigate the role of tumor necrosis factor (TNF)-alpha via prophylactic anti-TNF-alpha monoclonal antibody administration. DESIGN: Experimental, comparative hospital. SETTING: Laboratory in a university hospital. SUBJECTS: Male Sprague-Dawley rats, weighing 280 to 340 g. INTERVENTIONS: Intravenous injection of Escherichia coli endotoxin (5 mg/100 g) in the first group; injection of the same dose of endotoxin preceded by 2 mg/100 g of anti-TNF-alpha monoclonal antibody in the second group; injection of saline in the third (control) group. MEASUREMENTS AND MAIN RESULTS: TNF-alpha concentration was measured before and during the first 3 hrs in all three groups. Myocardial and vascular functional parameters were obtained, respectively, from Langendorff perfused hearts and isolated aortic rings. Adrenergic biochemical parameters (catecholamines, density and affinity of beta-receptors, and isoproterenol-stimulated myocardial cAMP) were determined 3 hrs after injections in the three groups. After endotoxin injection, serum TNF-alpha concentrations peaked at 60 mins (2496 +/- 412 pg/mL) and returned slowly to control values at 3 hrs; serum TNF-alpha concentrations remained under the limit of detection in the other two groups. When compared with the control group, plasma concentrations of epinephrine and norepinephrine were significantly (p < .05) increased. Baseline values for differential left ventricular pressure and coronary flow were significantly (p < .001, p < .01, respectively) reduced in the endotoxin group; heart rate remained unchanged. In the endotoxin and control groups, isoproterenol induced a similar increase in differential left ventricular pressure and in heart rate. Anti-TNF-alpha antibody increased cardiac response by partially preventing the decrease by endotoxin in differential left intraventricular pressure. Maximal specific binding of 125iodocyanopindolol and myocardial cAMP accumulation were significantly (p < .01) reduced in the endotoxin group in comparison with the control group. Anti-TNF-alpha antibody prevented the endotoxin-induced decrease in cAMP synthesis (p < .05) but did not modify the density of receptors. Affinity of receptors was similar in the three groups. In aortic rings, endotoxin administration significantly (p < .01) shifted the dose-response curve to norepinephrine to the right, both in the presence and absence of endothelium. NG-monomethyl-L-arginine significantly increased the contractions to attain the control level: p < .001 in the presence of endothelium; p < .05 in the absence of endothelium. Anti-TNF-alpha antibody did not prevent endotoxin-induced vascular hyporeactivity to norepinephrine in either endothelium-intact or -denuded rings, but partially attenuated the decrease in maximal response. CONCLUSIONS: In ex vivo experiments, 3 hrs after endotoxin injection, vascular responsiveness was sharply decreased. This impaired response was improved in vitro by the inhibition of nitric oxide. The heart response to isoproterenol, nevertheless, was maintained, even though there was an obvious decrease in receptor density and an impaired myocardial accumulation of cAMP. Anti-TNF-alpha antibody partially prevented the alteration of both myocardial pressure response to isoproterenol and biochemical parameters, and was not efficacious in preventing vascular hyporeactivity to vasoconstrictor agents.

L-NAME aggravates pulmonary oxygen toxicity in rats.

Exposure to high oxygen concentration leads to acute lung injury and death in rats after 72 h. The pathophysiology of this phenomenon relies on several mechanisms, including alteration of vascular reactivity, recruitment and activation of neutrophils and alveolar macrophages, production of cytokines and excess production of free radicals. In addition to its potent vasodilating effect, nitric oxide (NO) has also been reported to prevent free radical-mediated damage. We wanted to determine whether NG-nitro-L-arginine methyl ester (L-NAME), a NO synthase inhibitor, might modulate oxygen toxicity. In rats exposed to continuous high oxygen concentration, we studied the effect of administration of 50 mg.kg-1 of intraperitoneal L-NAME twice a day on the first day of oxygen exposure. L-NAME resulted in earlier death, since 57% of the animals exposed to oxygen and injected with L-NAME died within 60 h as compared to 22% of the animals exposed to oxygen and treated with saline (p < 0.01). Haematocrit and bronchoalveolar lavage fluid protein were also significantly increased in animals exposed to oxygen and receiving L-NAME. The lung water content was higher in the oxygen-exposed groups (p < 0.01) and slightly decreased by L-NAME (p < 0.05). Thiobarbituaric acid reactive substances (TBARS) were elevated in plasma (p < 0.01) and decreased in lung (p < 0.001) of oxygen-exposed animals, but no significant effect of L-NAME was observed. NG-nitro-L-arginine methyl ester had a deleterious effect in rats exposed to hyperoxia, which might suggest that endogenous nitric oxide has a protective role against hyperoxia-induced pulmonary lesions.

Alterations of myocardial and vascular adrenergic receptor-mediated responses in Escherichia coli-induced septic shock in the rat.

OBJECTIVES: To investigate responsiveness to exogenous catecholamines in rat bacteremic shock by studying both myocardial and vascular functional parameters; to determine in the same study the relationship of these parameters with other relevant biological parameters of the adrenergic pathway, such as myocardial beta-adrenergic receptors and cyclic adenosine monophosphate (cAMP); and to indirectly approach the roles of tumor necrosis factor-alpha (TNF-alpha) and nitric oxide. DESIGN: Experimental, comparative study. SETTING: Laboratory in a university hospital. SUBJECTS: Male Sprague-Dawley rats, weighing 270 to 320 g. INTERVENTIONS: Intravenous injection of live Escherichia coli DH5 alpha (2 x 10(10) organisms/kg) or saline (0.6 mL) and comparison of the two groups. MEASUREMENTS AND MAIN RESULTS: Mean arterial pressure and heart rate (HR) were recorded, and circulating TNF-alpha concentrations were measured, during the first 3 hrs after E. coli administration. Myocardial and vascular functional parameters were obtained, respectively, from Langendorff-perfused hearts and isolated aortic rings. Adrenergic biochemical parameters (catecholamines, density and affinity of beta-receptors, and isoproterenol-stimulated myocardial cAMP) were determined 3 hrs after E. coli injection. Mean arterial pressure decreased within 5 to 60 mins after bacteria injection and returned to basal levels in the last 2 hrs; HR was unchanged. Serum TNF-alpha concentrations peaked at 120 mins (7333 +/- 672 pg/mL) and were still increased at 3 hrs. Plasma concentrations of epinephrine and norepinephrine were significantly (p < .05) increased. Baseline values for differential left ventricular pressure and coronary flow were significantly (p < .0001, p < .001, respectively) reduced; HR remained unchanged. Isoproterenol induced a similar increase in differential left ventricular pressure and in HR. There was no decrease in the functional myocardial response to adrenergic stimulation. beta-adrenergic receptors were similar in density and in affinity in the two groups. Isoproterenol-stimulated myocardial cAMP was significantly (p < .01) reduced compared with the control group. In aortic rings, bacteria administration significantly (p < .01) shifted the dose-response curve to norepinephrine to the right, both in the presence and absence of endothelium. NG-monomethyl-L-arginine significantly increased the contractions to attain the control level: p < .001 in presence of endothelium; p < .05 in absence of endothelium. CONCLUSIONS: In ex vivo experiments, 3 hrs after E. coli injection, vascular responsiveness was sharply decreased. This impaired response was improved by inhibition of nitric oxide. The heart, nevertheless, was still able to modulate its inotropic and chronotropic response to isoproterenol, even though an impaired beta-adrenergic-receptor stimulation of cAMP was already present.

Effects of halothane, enflurane and isoflurane on contraction of rat aorta induced by endothelin-1.

Volatile anaesthetics induce hypotension by both indirect and direct effects; they have been reported to inhibit vasoconstriction produced by a variety of agonists. These studies were performed to see if halothane, enflurane and isoflurane attenuate endothelin-1-evoked contraction and if they interact with endothelium-dependent or -independent vasoactive substances. Rat aortic rings were suspended in aerated Krebs' solution (37 degrees C) and contracted by incremental doses of endothelin-1 5 x 10(-10) to 5 x 10(-8) mol litre-1. Volatile anaesthetics at 1 and 2 MAC were tested on endothelium intact and denuded rings. They were tested also on L-NAME incubated endothelium intact and indomethacin-incubated endothelium intact and denuded rings. Responses to endothelin-1 were compared in the presence and absence of volatile anaesthetics. Isoflurane at 1 and 2 MAC concentration, and enflurane at 2 MAC, induced a rightward shift of the dose-response curve obtained with endothelin-1 in both endothelium denuded and intact rings, associated with a decrease in maximal tension generated in the latter rings. In L-NAME-incubated endothelium intact rings and in indomethacin endothelium denuded rings, the anaesthetics induced a rightward shift of the dose-response curve without modification of maximal tension. In indomethacin-incubated endothelium intact rings there was significant attenuation of endothelin-1 contraction in control rings which was not enhanced by volatile anaesthetics in treated rings. The present study indicates that isoflurane at 1 and 2 MAC, and enflurane at 2 MAC, significantly decreased endothelin-1-induced contraction of isolated rat aorta. This inhibition was observed in both intact and denuded rings and probably involves mechanisms within the smooth muscle. Nevertheless, our results suggest that part of the anaesthetic-induced inhibition of endothelin-1-evoked vasocontraction involves an "indomethacin-like" effect on an endothelial-derived vasoconstricting cyclo-oxygenase product.

Use of pulsed-field gel electrophoresis as an epidemiologic tool during an outbreak of Pseudomonas aeruginosa lung infections in an intensive care unit.

OBJECTIVE: A retrospective study was performed to evaluate the use of DNA polymorphism analysis by pulsed-field gel electrophoresis (PFGE) in assessing the rate of exogenous contamination during an outbreak of Pseudomonas aeruginosa lung infections in an intensive care unit ICU. Another goal was to determine the risk factors, involved in the outbreak. DESIGN: Rectal swabs and tracheal secretions were cultured from all patients upon admission and thereafter once a week throughout their stay in the ICU. Resistance patterns were determined in all P. aeruginosa isolates. We determined the serotypes, pyocin types, plasmid profiles and total DNA macrorestriction patterns for isolates. The restriction fragment length polymorphism (RFLP) of Dra I total DNA digest was studied by PFGE. A retrospective case-control study was performed to determine the risk factors for P. aeruginosa bronchopulmonary colonization. SETTING: The study was carried out in the medical ICU of Besancon University Hospital (France). RESULTS: The typability, stability and reproducibility of phenotypic markers were not completely satisfactory. Only the RFLP profile satisfied all the criteria for a good typing technique. In four of the 17 patients, P. aeruginosa strains with the same DNA pattern were found. Among the previously reported risk factors for hospital-acquired bronchopulmonary infections, only invasive procedures were determined by multivariate analysis to be significant in our study group. The oropharynx and the bronchial tract are the most likely endogenous sources. CONCLUSION: PFGE-RFLP is a valuable tool for the epidemiologic study of P. aeruginosa. This typing method revealed that exogenous contamination is not always the major source of P. aeruginosa lung infections in mechanically ventilated patients in ICUs.

[Pseudomonas aeruginosa septicemia. Host-related risk factors in 82 episodes]. / Septicémies à Pseudomonas aeruginosa. Facteurs de risque liés à l'hôte au cours de 82 épisodes.

OBJECTIVES: The prognosis of septicaemia due to Pseudomonas aeruginosa is severe with mortality ranging from 32 to 73%. We retrospectively studied 82 episodes in order to determine whether risk factors could be identified. METHODS: Eighty-two episodes of Pseudomonas aeruginosa septicaemia, observed between 1986 and 1991, were analyzed. Risk of death within 2 days of the first positive blood culture (mortality = 19.5%) were assessed with univariate and multivariate analyses. RESULTS: Patient age ranged from 1 to 92 years. Most had been hospitalized in medical wards (49%) or intensive care units (28%) (NS). The type of septicaemia (several bacteria in 21%), the source of the infection (nosocomial in 78%), portal, predisposing factors (cancer, haematologic disease: 54%) and MacCabe index were not significantly correlated with risk of death at two days following first positive blood culture. With univariate analysis body temperature below 38,5 degrees C was significant (p = 0.007) for death at day 2 and appropriate antibiotic treatment after diagnosis was significant (p < 0.001) for absence of death on day 2. For multivariate analysis, chemotherapy and shock syndrome were significant (p = 0.005 and 0.09 respectively) for death at day 2 and appropriate antibiotic treatment was significant (p = 0.005) for absence of death on day 2. CONCLUSION: Antibiotic prescription appears to be the most easily controlled significant factor predictive of outcome in Pseudomonas aeruginosa septicaemia.

[Massive osteolysis : two cases displaying extreme clinical aspects]. / L'ostéolyse massive idiopathique : les aspects extrêmes de deux observations.

We have come across two cases of massive osteolysis showing completely opposite clinical aspects. The first case is a young man aged 28 showing osteolysis of the distal third of the right ulna. His disease was discovered after performing X-rays for minor trauma of the right forearm. He had never complained of his arm before and he only displayed a loss of 45° in pronation. We noted that osteolysis could already be seen on X-ray at plaster removal after 45 days of immobilisation, although the osteolysis was not noticed on the first X-rays.The second case concerns a 17-year-old man who was known to have a massive osteolysis of the pelvis ring and who had used a wheel-chair from the age of 8. While hospitalized for a severe infection of the testicles and scrotum, he developped a recurrent chylothorax that required surgical pleurodesis. This young man displayed no radiological evidence of this disease above the pelvis.A review of the literature allows us to clarify the still obscure pathogenic aspects of massive osteolysis, its classification, the different forms that may be encountered and the keys to diagnosis. The authors caution against aggressive treatment in certain areas where the disease remains benign.