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C Roussos

Publications and source records attributed to C Roussos.

At least 55 records · Page 3Linked to original sources
PubMed2001

Hypoxaemic reperfusion ameliorates the histopathological changes in the pig brain after a severe global cerebral ischaemic insult.

BACKGROUND AND PURPOSE: We have recently shown that hypoxaemic reperfusion, after an ischaemic brain insult, improves neurological outcome and decreases lipid peroxidation. In the present study, we investigated the effect of hypoxaemic reperfusion on brain histopathological changes. METHODS: Sixteen pigs subjected to a 10-min global cerebral ischaemia were either hypoxaemically (PaO2 = 35 mmHg, hypoxaemic reperfusion (HR) group, n = 8) or hyperoxaemically (PaO2 > 300 mmHg, control (C) group, n = 8) reperfused. The brains were removed 24 h after reperfusion and six neuropathological abnormalities were evaluated blindly and scored semi-quantitatively (0: normal to 3: severe injury) on eight representative regions of the brain. The overall cumulative score of the abnormalities and their regional prevalence, as well as the neurological outcome, were compared between the two groups. RESULTS: The neuronal degeneration, assessed in terms of cumulative score (P = 0.002) and regional prevalence (P = 0.025 to P = 0.041), was lower in the HR group than in the C group. Spongy degeneration attained statistically significant difference only in cerebellum (P = 0.002) and inflammation only in hippocampus (P = 0.046) but the difference in the cumulative score of these abnormalities was not statistically significant. The difference of the three neurological assessments over time was statistically significant between the two groups, i.e. after resuscitation (P = 0.001), at 8 h (P = 0.006) and at 24 h (P = 0.001) after reperfusion. CONCLUSIONS: Hypoxaemic reperfusion during resuscitation from a severe global ischaemic cerebral insult is associated with statistically significantly fewer histopathological changes of the brain than in controls. This is associated with a superior neurological outcome.

Animals↗
PubMed2001

Combined expression of p53, Bcl-2, and p21WAF-1 proteins in lung cancer and premalignant lesions: association with clinical characteristics.

We examined p53, p21WAF-1, and Bcl-2 protein expression in malignant and nonmalignant bronchial specimens obtained during bronchoscopy from 60 lung cancer patients. Twenty-six (43.3%), 36 (60%), and 20 (33.3%) of the tumors were p53, p21WAF-1, and Bcl-2 positive, respectively. High-level p53 and Bcl-2 expression characterized advanced preneoplastic lesions, while hyperplasias, squamous metaplasias, and mild dysplasias exhibited low levels of expression. There was no difference between early and advanced preneoplastic lesions in the level of p21WAF-1, expression. A history of heavy smoking was associated with p21WAF-1, expression in preneoplastic lesions (p = 0.022) and tumors (p = 0.032). p53(-)/p21WAF-1(++)/bcl-2(-) was the only significant independent predictor of lower clinical stage (OR: 0.88, p = 0.038). In univariate analysis, survival of NSCLC patients was affected by disease stage (p <0.001) and tumor histology (p = 0.018). While single-protein expression was not associated with prognosis, the combined immunophenotype p53(-)/p21WAF-1(++)/bcl-2(-) predicted longer survival (p = 0.03). In multivariate analysis, only the TNM stage was found to be a prognostic factor for NSCLC. We conclude that p53 and Bcl-2 alterations may happen early in bronchial carcinogenesis and that absence of these alterations in combination with p21WAF-1, overexpression may be associated with a less aggressive tumor behavior.

Aged↗
PubMed2001

Aspergillus bronchitis causing atelectasis and acute respiratory failure in an immunocompromised patient.

Aspergillus tracheobronchitis is an uncommon clinical form of invasive aspergillosis with fungal infection limited entirely or predominantly to the tracheobronchial tree. We report a case of Aspergillus fumigatus bronchitis, diagnosed by fiberoptic bronchoscopy, with fungal growth completely occluding the left main bronchus leading to lung collapse and acute respiratory failure in a 60-year-old male with erythroleukemia and profound granulocytopenia.

Aspergillosis↗
PubMed2001

Diagnostic and prognostic significance of squamous cell carcinoma antigen in non-small cell lung cancer.

Squamous cell carcinoma antigen (SCC-Ag) is a glycoprotein secreted by non-small cell lung tumours (NSCLC). This study investigated the diagnostic and prognostic significance of SCC-Ag in NSCLC. Receiver operating characteristic (ROC) curve analysis was used to test the diagnostic performance of the SCC-Ag and determine the optimal threshold value in a group of 100 NSCLC patients undergoing surgery and 50 age matched healthy controls. This threshold was then prospectively validated in a group of 53 patients and 49 healthy controls. The prognostic significance of the preoperative SCC-Ag level and its postoperative decrease were tested using univariate and multivariate proportional hazard models. The area under the ROC curve was 0.71+/-0.04, and the best cutoff value was 1.4 ng/ml. This discriminated patients in the validation group, with a sensitivity of 0.55 and a specificity of 1.0. The hazard ratio was 0.144 (95% CI 0.074-0.281) for the postoperative decrease in the SCC Ag, and 5.823 (3.299-10.278) for the preoperative SCC Ag level. Multivariate analysis revealed that only disease stage and patients' age are strong prognostic factors for survival. In conclusion, the SCC-Ag serum level has moderate diagnostic role in NSCLC. Both the preoperative SCC-Ag level and its postoperative decrease have prognostic significance, yet inferior to the disease stage and the patient's age.

Adenocarcinoma↗
PubMed2001

Early recovery of oxygen kinetics after submaximal exercise test predicts functional capacity in patients with chronic heart failure.

BACKGROUND: Oxygen (O2) uptake at peak exercise (VO2 peak) is an objective measurement of functional capacity in patients with chronic heart failure (CHF). The significance of recovery O2 kinetics parameters in predicting exercise capacity, and the parameters of submaximal exercise testing have not been thoroughly examined. METHODS AND RESULTS: Thirty-six patients (mean age = 48+/-14 years) with CHF and New York Heart Association functional class I, II, or III, and eight healthy volunteers (mean age = 39+/-13 years) were studied with maximal and submaximal cardiopulmonary exercise testing (CPET). The first degree slope of O2 uptake decay during early recovery from maximal (VO2/t-slope), and submaximal exercise (VO2/t-slope)(sub), were calculated, along with VO2 half-time (T(1/2)VO2). Patients with CHF had a longer recovery of O2 uptake after exercise than healthy volunteers, expressed by a lower VO2/t-slope (0.616+/-0.317 vs. 0.956+/-0.347 l min(-1) min(-1), P=0.029) and greater T(1/2)VO2 (1.28+/-0.30 vs. 1.05+/-0.15 min, P = 0.005). VO2/t-slope correlated with the VO2 peak (r = 0.84, P<0.001), anaerobic threshold (r = 0.79, P<0.001), and T(1/2)VO2, a previously established estimate of recovery O2 kinetics (r = -0.59, P<0.001). (VO2/t-slope)(sub) was highly correlated with VO2/t-slope after maximal exercise (r=0.87, P<0.001), with the VO2 peak (r=0.87, P<0.001) and with T(1/2)VO2 after maximal exercise (r=-0.62, P<0.001). VO2/t-slope after maximal and submaximal exercise was reduced in patients with severe exercise intolerance (F=9.3, P<0.001 and F=12.8, P<0.001, respectively). CONCLUSIONS: Early recovery O2 kinetics parameters after maximal and submaximal exercise correlate closely with established indices of exercise capacity in patients with CHF and in healthy volunteers. These findings support the use of early recovery O2 kinetics after submaximal exercise testing as an index of functional capacity in patients with CHF.

Adult↗
PubMed2001

Exhaled nitric oxide in seasonal allergic rhinitis: influence of pollen season and therapy.

Exhaled nitric oxide (eNO) has been proposed as a potential indirect marker of lower airway inflammation in asthma. To investigate the existence of lower airways inflammation in allergic rhinitis eNO measurements were performed in 32 patients with symptomatic and asymptomatic seasonal allergic rhinitis early in and out of pollen seasons and in 80 healthy volunteers. To further define how exhaled NO is modified by therapy, NO levels were detected following 1-month treatment with either inhaled steroids or non-steroids therapy with nedocromil. Exhaled NO (mean +/- SE) was significantly elevated in patients with seasonal allergic rhinitis with and without symptoms (24.2 + 2.5 and 13.9 + 2.9 ppb, respectively) as compared to healthy volunteers (4.5 + 0.3 ppb) both in and out of pollen season (21.2 + 2.1 and 9.0 + 1.4 p.p.b., respectively) with a higher increase during the allergen exposure in season. Higher levels of exhaled NO were detected in patients with symptoms, either from the upper or lower airways, and with bronchial hyperreactivity. The increased exhaled NO in symptomatic patients was reduced only by inhaled steroids and not by nedocromil. These findings possibly suggest the existence of lower airway inflammation in both symptomatic and asymptomatic patients with seasonal allergic rhinitis in and out of pollen season. Thus, exhaled NO may be used as a non-invasive index for early detection of lower airway inflammation and for monitoring the optional treatment in patients with seasonal allergic rhinitis.

Adult↗
PubMed2001

Effects of severity of chronic obstructive pulmonary disease on thyroid function.

To investigate thyroid function in chronic obstructive pulmonary disease (COPD), 46 consecutive patients (35 men) with stable, mild-to-severe disease, having a mean (SD) age of 67 +/- 7 years were studied. All subjects underwent pulmonary function tests (PFTs), arterial blood gas determination, and measurement of serum total thyroxine (TT4), total triiodothyronine (TT3), resin T3 uptake (RT3U), reverse triiodothyronine (rT3), and thyroid-stimulating hormone (TSH) levels. The free thyroxine and free triiodothyronine indexes (FT4I = RT3U/30TT4 and FT3I = RT3U/30TT3, respectively) along with the TT3/TT4 ratio were calculated; the latter was used as a marker of peripheral conversion of thyroxine into triiodothyronine. Interleukin (IL)-6 was also measured to evaluate its potential associations with thyroidal hormone levels. On the basis of forced expiratory volume in 1 second (FEV1), patients were divided in 2 groups: group 1, (FEV1 > or = 50% of predicted, n = 26), with mild-to-moderate COPD and group 2 (FEV1 < 50% of predicted, n = 20) having severe disease. All subjects had normal serum thyroid hormone levels; for the entire COPD population, mean values were 7.80 +/- 1.60 microg/dL for TT4, 1.12 +/- 0.20 ng/mL for TT3, 29.0 +/- 1.88 for RT3U, 7.54 +/- 1.34 for FT4I, 1.07 +/- 0.16 for FT3I, 18.71 +/- 5.89 ng/dL for rT3, and 1.15 +/- 0.6 microU/mL for TSH. Mean TT3/TT4 ratio was 0.14 +/- 0.03. In group 1, TT3, TT4, and TT3/TT4 ratio did not correlate with age, FEV1, PaO2, or inhaled corticosteroids. Similarly, in group 2, TT3 and TT4 were unrelated to the above-mentioned variables; however, there was a strong positive correlation between TT3/TT4 ratio and PaO2 (r =.61, P =.004). IL-6 was within normal limits in all subjects, and it did not correlate with any thyroid hormone either in group 1 or in group 2. It is concluded that in stable COPD, severity of disease through hypoxemia is important in determining the peripheral metabolism of thyroid hormones. Whether this constitutes an adaptation is not known.

Aged↗
PubMed2001

Pulmonary hypertension, interstitial lung fibrosis, and lung iron deposition in thalassaemia major.

Although restrictive lung disease is the predominant abnormality of pulmonary function in patients with thalassaemia major (TM), its aetiology and its association with pulmonary hypertension (PH) detected in some patients with TM remains unknown. We report a patient with TM, iron overload, frequent pulmonary infections, and progressive severe precapillary PH over the previous 5 years. A severe restrictive pattern and interstitial lung fibrosis were revealed by pulmonary function tests and high resolution computed tomography, respectively. This presentation suggests that interstitial fibrosis may complicate lung involvement in TM and can significantly contribute to the development of PH.

Adult↗
PubMed2001

Reactive oxygen species stimulate VEGF production from C(2)C(12) skeletal myotubes through a PI3K/Akt pathway.

Vascular endothelial growth factor (VEGF) is a potent angiogenic stimulus, the expression of which increases in skeletal muscle after exercise. Because exercise is also accompanied by increased intramuscular reactive oxygen species (ROS) generation, we tested the hypothesis that ROS stimulate VEGF production from skeletal myotubes. Differentiated C(2)C(12) skeletal myotubes exposed to ROS-producing agents exhibited a concentration-dependent increase in VEGF production, whereas undifferentiated myoblasts did not respond to oxidants. Moreover, conditioned medium from ROS-treated myotubes increased the bovine lung microvascular cell proliferation rate. To study the mechanism(s) involved in the stimulation of VEGF production by ROS, myotubes were pretreated with a selective phosphatidylinositol 3-kinase (PI3K) inhibitor, LY-294002, before being exposed to hydrogen peroxide or pyrogallol. LY-294002 attenuated both Akt phosphorylation and VEGF production. In addition, oxidants increased nuclear factor-kappaB-dependent promoter activity in transiently transfected myotubes; however, pretreatment with the pharmacological inhibitor of nuclear factor-kappaB, diethyldithiocarbamate, did not affect the oxidant-stimulated VEGF release. We conclude that ROS induce VEGF release from myotubes via a PI3K/Akt-dependent pathway.

Animals↗
PubMed2001

Prolonged oxygen kinetics during early recovery from maximal exercise in adult patients with cystic fibrosis.

STUDY OBJECTIVES: To explore the significance of oxygen kinetics during early recovery after maximal cardiopulmonary exercise testing (CPET) in the assessment of functional capacity and severity of the disease in cystic fibrosis (CF) patients. PARTICIPANTS: Eighteen patients with CF (9 male/9 female; mean +/- SD age, 23 +/- 13 years) and 11 healthy subjects (3 male/8 female; mean age, 29 +/- 4 years) underwent maximum CPET on a treadmill. Breath-by-breath analysis was used for measuring oxygen consumption (VO(2)), carbon dioxide production, and ventilation. Maximum VO(2) (VO(2)peak) and the first-degree slope of VO(2) decline during early recovery (VO(2)/t-slope) were calculated. To assess the severity of the disease, we used standard indexes like FEV(1) (% predicted), VO(2)peak, and a widely accepted system of clinical evaluation, the Schwachman score (SS). RESULTS: VO(2)/t-slope was significantly lower in CF patients compared to healthy subjects (0.61 +/- 0.31 L/min/min vs 1.1 +/- 0.13 L/min/min; p < 0.01) and was closely correlated to FEV(1)(r = 0.90, p < 0.001), VO(2)peak (r = 0.81, p < 0.001), and the SS (r = 0.81, p < 0.001). The multivariate analysis showed that the only independent predictor of the SS is the VO(2)/t-slope. CONCLUSION: We conclude that in CF patients, the prolonged oxygen kinetics during early recovery from maximal exercise is related to the disease severity.

Adolescent↗
PubMed2001

Luteolin inhibits an endotoxin-stimulated phosphorylation cascade and proinflammatory cytokine production in macrophages.

Flavonoids are naturally occurring polyphenolic compounds with a wide distribution throughout the plant kingdom. In the present study, we compared the ability of several flavonoids to modulate the production of proinflammatory molecules from lipopolysaccharide (LPS)-stimulated macrophages and investigated their mechanism(s) of action. Pretreatment of RAW 264.7 with luteolin, luteolin-7-glucoside, quercetin, and the isoflavonoid genistein inhibited both the LPS-stimulated TNF-alpha and interleukin-6 release, whereas eriodictyol and hesperetin only inhibited TNF-alpha release. From the compounds tested luteolin and quercetin were the most potent in inhibiting cytokine production with an IC(50) of less than 1 and 5 microM for TNF-alpha release, respectively. To determine the mechanisms by which flavonoids inhibit LPS signaling, we used luteolin and determined its ability to interfere with total protein tyrosine phosphorylation as well as Akt phosphorylation and nuclear factor-kappaB activation. Pretreatment of the cells with luteolin attenuated LPS-induced tyrosine phosphorylation of many discrete proteins. Moreover, luteolin inhibited LPS-induced phosphorylation of Akt. Treatment of macrophages with LPS resulted in increased IkappaB-alpha phosphorylation and reduced the levels of IkappaB-alpha. Pretreatment of cells with luteolin abolished the effects of LPS on IkappaB-alpha. To determine the functional relevance of the phosphorylation events observed with IkappaB-alpha, macrophages were transfected either with a control vector or a vector coding for the luciferase reporter gene under the control of kappaB cis-acting elements. Incubation of transfected RAW 264.7 cells with LPS increased luciferase activity in a luteolin-sensitive manner. We conclude that luteolin inhibits protein tyrosine phosphorylation, nuclear factor-kappaB-mediated gene expression and proinflammatory cytokine production in murine macrophages.

Animals↗
PubMed2001

Echocardiographic and ambulatory electrocardiographic findings in elite water-polo athletes.

The aim of this study was to investigate the echocardiographic and electrocardiographic findings in top water-polo athletes and test the hypothesis that their hearts exhibit dilatation associated with hypertrophy secondary to the mixed type (isotonic and isometric) of exercise they are subjected to. Eighteen athletes of the Greek national water-polo team and 15 healthy sedentary men serving as controls were studied. All underwent an echocardiogram, a standard 12-lead ECG and 24-h ECG monitoring. In athletes, as compared to healthy controls, an increase was detected in the following indices: left ventricular (LV) end-diastolic diameter index (EDDI-LV) (by 10%; P = 0.02), interventricular septal thickness (IVS) (by 32%; P<0.001), thickness of the posterior wall (PW) (by 29%; P<0.001), relative wall thickness (IVS + PW/EDD-LV) (by 12%; P < 0.001) and LV mass index (by 82%; P < 0.001). Mild asymmetric thickening of the septum (IVS/PW = 1.40 and 1.37) was measured in two athletes. LV fractional shortening was normal. Standard 12-lead ECG abnormalities (LV hypertrophy or abnormal repolarization pattern) were observed in 33% of athletes. Athletes had sinus bradycardia during day and night, respiratory arrhythmia (RA) (83% vs 40% of controls; P = 0.03) and sinus pauses (SP) (39% vs 0% of controls; P = 0.02), with occassional arrhythmias and conduction abnormalities. We conclude that top water-polo athletes have dilatation combined with substantial hypertrophy and normal systolic function of the LV In addition they present bradycardia, RA and SP, with occassional arrhythmias and conduction abnormalities.

Adaptation, Physiological↗
PubMed2000

Pulmonary capillary endothelium-bound angiotensin-converting enzyme activity in acute lung injury.

BACKGROUND: Pulmonary capillary endothelium-bound (PCEB) angiotensin-converting ectoenzyme (ACE) activity alteration is an early, sensitive, and quantifiable lung injury index in animal models. We hypothesized that (1) PCEB-ACE alterations can be found in patients with acute lung injury (ALI) and (2) PCEB-ACE activity correlates with the severity of lung injury and may be used as a quantifiable marker of the underlying pulmonary capillary endothelial dysfunction. METHODS AND RESULTS: Applying indicator-dilution techniques, we measured single-pass transpulmonary hydrolysis of the synthetic ACE substrate (3)H-benzoyl-Phe-Ala-Pro (BPAP) in 33 mechanically ventilated, critically ill patients with a lung injury score (LIS) ranging from 0 (no lung injury) to 3.7 (severe lung injury) and calculated the kinetic parameter A(max)/K(m). Both parameters decreased early during the ALI continuum and were inversely related to APACHE II score and LIS. Hydrolysis decreased with increasing cardiac output (CO), whereas 2 different patterns were observed between CO and A(max)/K(m). CONCLUSIONS: PCEB-ACE activity decreases early during ALI, correlates with the clinical severity of both the lung injury and the underlying disease, and may be used as a quantifiable marker of underlying pulmonary capillary endothelial dysfunction.

Adolescent↗
PubMed2000

A role for transoesophageal echocardiography in the early diagnosis of catastrophic antiphospholipid syndrome.

We describe a previously healthy 28-year-old woman who presented with the clinical picture of large vessel occlusions (stroke with left hemiparesis, myocardial infarction) and developed multi-organ failure (i.e. kidneys, heart, brain, liver, blood, skin) over a very short period of time. Peripheral blood smear was consistent with thrombotic thrombocytopenic purpura. Transesophageal echocardiogram was supportive of the diagnosis of catastrophic antiphospholipid syndrome (CAPS), revealing Libman-Sacks endocarditis. Blood cultures were negative, anticardiolipin antibodies were highly increased and lupus anticoagulant was positive. Cerebral and coronary angiograms were negative, suggesting possible microthrombotic occlusive disease in the setting of CAPS.

Acute Disease↗
PubMed2000

Enterococcal infections in a Greek intensive care unit: a 5-y study.

In this study we determined the incidence, resistance pattern, and mortality rate associated with infection caused by Enterococcus faecalis and Enterococcus faecium among patients in a multidisciplinary intensive care unit (ICU). A total of 111 patients with E. faecalis and 60 with E. faecium infections were identified during a 5-y period (1992-96). We observed an increase in the incidence of enterococcal infections (from 5.46 to 8.46 per 1000 patients-days, p = 0.0112), due mainly to the increased incidence of E. faecium (from 0.45 to 4.06 per 1000 patients-days, p = 0.002). Blood was the most common site of enterococcus isolation. E. faecium was more resistant to antibiotics than E. faecalis, but no vancomycin resistant enterococcus was isolated. Patients with E. faecium infection had a significantly higher mortality than patients with E. faecalis infection (66% vs. 41.5%, p = 0.0035 for infection from any site and 85.7 vs. 47.7%, p = 0.012 for bacteremic patients). r 4n- D I .- .- - .. . .

Adolescent↗