Effect of Atrial Pressure Increase on Effective Refractory Period and Vulnerability to Atrial Fibrillation in Patients with Lone Atrial Fibrillation

Background: There is evidence suggesting that atrial fibrillation (AF) may be induced by acute increase of atrial pressure. The aim of the present study was to investigate the effect of alterations in atrial pressure, induced by varying the atrioventricular (AV) interval, on atrial refractoriness, and on the frequency of induction of (AF), in patients with a history of lone atrial fibrillation (LAF).Methods and Results: Twenty-five patients were included in this study. The patients were divided in two groups: the LAF group, and the control group. None of the patients in either group had organic heart disease. Effective refractory period (ERP) and duration of atrial extrastimulus electrogram (A₂) were measured at two right atrial sites (high lateral wall, atrial appendage) during AV pacing (cycle length: 500 msec) with different AV intervals. Peak, minimal and mean atrial pressure increased from 8.57 ± 2.37 to 18.14 ± 4.74 mm Hg, 2 ± 2.23 to 5.14 ± 2.60 mm Hg (p = 0.0001) and from 4.28 ± 1.6 mm Hg to 9.77 ± 2.9 mm Hg (p = 0.001), respectively during AV interval modification. During lateral and atrial appendage pacing, with a progressive decrease of AV interval to 160, 100, 80, 40, 0 msec, the ERP, the dispersion of ERP, functional refractory period (FRP), A2 and latency period (LP) did not change significantly, in both groups. The frequency of induction of AF was not statistically different in both lateral atrial wall and appendage, during pacing in different AV intervals.Conclusions: This study demonstrates that alterations in the intraatrial pressure does not have important effects on atrial refractoriness and does not increase vulnerability to AF in patients with a history of LAF.     

Alterations in the fibrinolytic system components during acute myocardial infarction

The purpose of this study was to evaluate the changes in tissue-plasminogen activator (t-PA), plasminogen activator inhibitor - type 1 (PAI-1) and D-dimer (DD) antigen plasma levels in acute myocardial infarction (AMI) patients after thrombolytic therapy with two different thrombolytic agents, rt-PA or acetyl-streptokinase and to find out any correlation between the plasma t-PA, PAI-1 and DD levels with the infarct size as it is estimated from the peak of serum CPK levels. The plasma antigen levels of t-PA, PAI-1 and DD were measured by the enzyme immunoassay method (Stago), in 57 consecutive patients (M = 46, F = 11, mean age 55.6 +/- 8.8 years) and in 25 normal subjects (M = 18, F = 7, mean age 54.0 +/- 5.5 years). In 47 out of the 57 patients who were treated successfully with 100 mg of rt-PA (26 patients) or with 1.5 MU 21 of acetyl-streptokinase, as well as in 10 patients who were not treated, samples were obtained again 4 and 24 hours after the end of thrombolytic therapy or admission, respectively. During the acute phase of myocardial infarction the t-PA, PAI-1 and DD antigen plasma levels were significantly higher than in healthy people. There were no significant changes in the t-PA, PAI-1 and DD plasma levels of the patients who were not treated with a thrombolytic agent. We found a significant elevation of t-PA (p < 0.001), PAI-1 (p < 0.05) and DD (p < 0.001) after 4 hours in comparison with the baseline (at presentation, before therapy). After 24 hours the t-PA and DD plasma levels remained significantly higher (p < 0.001) while the PAI-1 plasma levels returned to the pre-therapy levels. There were no significantly different changes in the t-PA, PAI-1 and DD plasma levels of either group of patients, treated with rt-PA or acetyl-streptokinase while the t-PA and PAI-1 levels were positively correlated with infarct size as estimated from peak serum CPK levels.     

Osteoarticular Infections Caused by Non-Aspergillus Filamentous Fungi in Adult and Pediatric Patients: A Systematic Review

Osteoarticular mycoses due to non-Aspergillus moulds are uncommon and challenging infections.A systematic literature review of non-Aspergillus osteoarticular mycoses was performed using PUBMED and EMBASE databases from 1970 to 2013.Among 145 patients were 111 adults (median age 48.5 [16–92 y]) and 34 pediatric patients (median age 7.5 [3–15 y]); 114 (79.7%) were male and 88 (61.9%) were immunocompromised. Osteomyelitis was due to direct inoculation in 54.5%. Trauma and puncture wounds were more frequent in children (73.5% vs 43.5%; P = 0.001). Prior surgery was more frequent in adults (27.7% vs 5.9%; P = 0.025). Vertebral (23.2%) and craniofacial osteomyelitis (13.1%) with neurological deficits predominated in adults. Lower limb osteomyelitis (47.7%) and knee arthritis (67.8%) were predominantly seen in children. Hyalohyphomycosis represented 64.8% of documented infections with Scedosporium apiospermum (33.1%) and Lomentospora prolificans (15.8%) as the most common causes. Combined antifungal therapy and surgery was used in 69% of cases with overall response in 85.8%. Median duration of therapy was 115 days (range 5–730). When voriconazole was used as single agent for treatment of hyalohyphomycosis and phaeohyphomycosis, an overall response rate was achieved in 94.1% of cases.Non-Aspergillus osteoarticular mycoses occur most frequently in children after injury and in adults after surgery. Accurate early diagnosis and long-course therapy (median 6 mo) with a combined medical-surgical approach may result in favorable outcome.     

High-resolution CT findings in mild pulmonary fat embolism

OBJECTIVE: The aim of this article is to describe the high-resolution CT (HRCT) findings in mild cases of fat embolism syndrome (FES). MATERIAL AND METHODS: Nine patients with FES were examined with HRCT of the lungs (collimation, 1 mm/edge-enhancement algorithm). The median age of the patients was 26 years (range, 17 to 35 years). Five cases were included prospectively, and four cases were reviewed retrospectively. Of the major clinical criteria for FES, respiratory signs were present in six patients, CNS signs were present in two patients, and petechiae was present in six patients. HRCT patterns were recorded and analyzed. The type of injury and FES-associated clinical findings were also recorded. RESULTS: HRCT findings included ground-glass opacities in seven patients, associated with thickened interlobular septa in five patients and a patchy distribution resulting in a geographic appearance in four patients. A nodular pattern was observed in two patients. Resolution of the abnormalities occurred within 16.4 days (range, 7 to 25 days). CONCLUSION: The HRCT findings of mild fat embolism consist of bilateral ground-glass opacities and thickening of the interlobular septa. Centrilobular nodular opacities are present in some patients.     

Laryngopharyngeal reflux disease in the Greek general population,prevalence and risk factors

Gait function may be impaired in patients with vestibular disorders, making gait assessment in the clinical setting relevant for this patient population. The purpose of this study was to evaluate the discriminant validity of a gait assessment protocol between patients with vestibular disorders and healthy participants. Furthermore, test re-test reproducibility and the measurement error of gait performance measures in patients with vestibular lesions was performed under different walking conditions. Gait parameters of thirty-five patients with vestibular disorders and twenty-seven healthy controls were assessed twice with the GAITRite® system. Discriminant validity, reproducibility (intra class correlation [ICC]) and the measurement error (standard error of measurement [SEM], smallest detectable change [SDC]) were determined for gait speed, cadence and step length. Bland-Altman plots were made to assess systematic bias between tests. A significant effect of grouping on gait performance indicates discriminant validity of gait assessment. All tests revealed differences between patients and healthy controls (p < 0.01). The ICCs for test re-test reproducibility were excellent (0.70-0.96) and measurement error showed acceptable SDC values for gait parameters derived from three walking conditions (9-19 %). Bland-Altman plots indicated no systematic bias. Good validity and reproducibility of GAITRite® system measurements suggest that this system could facilitate the study of gait in patients with vestibular disorders in clinical settings. The SDC values for gait are generally small enough to detect changes after a rehabilitation program for patients with vestibular disorders.     

Distinct von Hippel-Lindau gene and hypoxia-regulated alterations in gene and protein expression patterns of renal cell carcinoma and their effects on metabolism

During the last decade the knowledge about the molecular mechanisms of the cellular adaption to hypoxia and the function of the “von Hippel Lindau” (VHL) protein in renal cell carcinoma (RCC) has increased, but there exists little information about the overlap and differences in gene/protein expression of both processes. Therefore the aim of this study was to dissect VHL- and hypoxia-regulated alterations in the metabolism of human RCC using ome-based strategies. The effect of the VHL- and hypoxia-regulated altered gene/protein expression pattern on the cellular metabolism was analyzed by determination of glucose uptake, lactate secretion, extracellular pH, lactate dehydrogenase activity, amino acid content and ATP levels. By employing VHL⁻/VHL⁺ RCC cells cultured under normoxic and hypoxic conditions, VHL-dependent, HIF-dependent as well as VHL-/HIF-independent alterations in the gene and protein expression patterns were identified and further validated in other RCC cell lines. The genes/proteins differentially expressed under these distinct conditions were mainly involved in the cellular metabolism, which was accompanied by an altered metabolism as well as changes in the abundance of amino acids in VHL-deficient cells. In conclusion, the study reveals similarities, but also differences in the genes and proteins controlled by VHL functionality and hypoxia thereby demonstrating differences in the metabolic switch of RCC under these conditions.     

Highly sensitive and specific novel biomarkers for the diagnosis of transitional bladder carcinoma

Transitional bladder carcinoma (BCa) is prevalent in developed countries, particularly among men. Given that these tumors frequently recur or progress, the early detection and subsequent monitoring of BCa at different stages is critical. Current BCa diagnostic biomarkers are not sufficiently sensitive for substituting or complementing invasive cystoscopy. Here, we sought to identify a robust set of urine biomarkers for BCa detection. Using a high-resolution, mass spectrometry-based, quantitative proteomics approach, we measured, compared and validated protein variations in 451 voided urine samples from healthy subjects, non-bladder cancer patients and patients with non-invasive and invasive BCa. We identified five robust biomarkers: Coronin-1A, Apolipoprotein A4, Semenogelin-2, Gamma synuclein and DJ-1/PARK7. In diagnosing Ta/T1 BCa, these biomarkers achieved an AUC of 0.92 and 0.98, respectively, using ELISA and western blot data (sensitivity, 79.2% and 93.9%; specificity, 100% and 96.7%, respectively). In diagnosing T2/T3 BCa, an AUC of 0.94 and 1.0 was attained (sensitivity, 86.4% and 100%; specificity, 100%) using the same methods. Thus, our multiplex biomarker panel offers unprecedented accuracy for the diagnosis of BCa patients and provides the prospect for a non-invasive way to detect bladder cancer.