Perylene Toxicity in the Estuarine Environment of Ria de Aveiro (Portugal)

Perylene, a 5-ring polycyclic aromatic hydrocarbon is common in estuarine sediments and its toxicity in the benthic and planktonic compartments is not yet clarified. The objectives of this work were: (1) to follow the toxicity of high concentrations of perylene (110 mg l⁻¹) on benthic bacteria and macrofauna (amphipod Corophium multisetosum); (2) to determine the effects of a low load of perylene (2 μg l⁻¹) on the metabolism of suspended bacteriobenthos after 9-day exposure, mimicking the effects of tidal erosion; (3) to contrast the effects of this low perylene load on the particle-free bacterioplankton and on the suspended and particle-adhered bacteriobenthos. No impact was detected in bacterial abundance exposed to 110 mg perylene l⁻¹ for 9 days. This concentration of perylene evoked no acute effects in C. multisetosum but, chronic toxicity assays revealed statistically significant negative effects on survival, growth and number of pregnant females. The bacterioplankton and the suspended bacteriobenthos, exposed to 2 μg perylene l⁻¹ during 2 weeks, responded with altered profiles of activity when compared to the control suspension. These values ranged, respectively, for bacterial biomass production from 134 to 210 and from 24 to 184 μg C l⁻¹ h⁻¹, for aminopeptidase from 1824 to 11,127 and from 1464 to 15,488 nmol l⁻¹ h⁻¹, and for β-glucosidase from 87 to 400 and from 57 to 1278 nmol l⁻¹ h⁻¹. The rate of oxygen consumption in the perylene-exposed suspension (0.04–2.85 mmol O₂ kg⁻¹ dw sed h⁻¹) exhibited a clearly distinct profile in relation to the control (0.57–1.60 mmol O₂ kg⁻¹ dw sed h⁻¹). The overall reactivity of the bacteriobenthos to perylene was interpreted as the result of toxic pressure followed by evolution of a diverse bacterial community.     

New technologies applied to ultrasound diagnosis of sports injuries

Introduction  The aim of this study was to compare the ultrasound images of different soft tissue lesions from two different portable sonography devices: a conventional portable sonography device (ultrasound [US]-A, Micromaxx model; Sonosite Inc., Bothell, WA, USA), and a recently marketed compact device (US-B, Logiq e; General Electric Healthcare, Wauwatosa, WI, USA). The US-B device uses the new technologies of tissue harmonic imaging, real-time compound ultrasound, panoramic view, three-dimensional imaging, and virtual convex imaging. Methods  We compared ultrasound images of six different types of soft tissue lesions (muscle contusion, muscle strain, patellar tendinosis, calcifying patellar tendinosis, rupture of the lateral internal ligament of the knee, and deep infrapatellar synovial bursa), from six different subjects. Analysis of images was performed by the same ultrasound specialist. In accordance with the classical criteria for ultrasound studies, the following quantitative indicators and parameters of ultrasound quality were used to evaluate the images: degree of echogenicity, size of the lesion area, aspect, shape, borders, and overall visualization. Results  In muscle lesions due to contusion, not only is the edematous area better visualized with the new system, but definition of hemorrhagic area borders and their content is especially increased. In lesions of the tendons, the new system affords better definition of the borders of the hypoechogenic area of tendinous degeneration and perfect visualization of the extension of the damaged area using a panoramic study. Sonographic study of ligaments with chronic lesions permits visualization of scar areas. Finally, use of the new system with a small synovial bursa shows the content of the bursa and thickness of the walls more clearly. Conclusion  Overall, the quantitative indicators and parameters of image quality performed in this study of common sports lesions demonstrate the improvement in visualization of damaged soft tissues with the new technologies now incorporated into portable sonography devices.     

Three-dimensional power Doppler vascular network assessment of adnexal masses: intraobserver and interobserver agreement analysis.

OBJECTIVE: The purpose of this study was to assess intraobserver and interobserver agreement for tumor vascular network evaluation as assessed by 3-dimensional (3D) power Doppler sonography for discriminating benign from malignant adnexal masses. METHODS: Stored 3D power Doppler angiographic volume data from 39 women with a diagnosis of a vascularized adnexal mass who were evaluated and treated at our institution were retrieved from our database for analysis. Two different examiners (observer A, with 6 years of experience in 3D sonography; and observer B, with 1 year of experience) reviewed 3D sonograms blinded to each other. Three-dimensional vascular network reconstruction was done with surface rendering in the color mode. Malignancy was considered in the presence of at least 2 of the following: irregular branching, vessel caliber changes, microaneurysms, and vascular lakes. A definitive histologic diagnosis was obtained in all cases. Intraobserver and interobserver agreement rates were estimated by calculating the kappa index. RESULTS: Twenty (51%) tumors were malignant, and 19 (49%) were benign. Intraobserver agreement was good for observer A (kappa = 0.69) and moderate for observer B (kappa = 0.54). Interobserver agreement was moderate (kappa = 0.49). CONCLUSIONS: We found intraobserver and interobserver agreement to be moderate for 3D power Doppler assessment of the vascular network in adnexal masses.     

Noninvasive versus invasive microbial investigation in ventilator-associated pneumonia: evaluation of outcome

Noninvasive and invasive diagnostic techniques have been shown to achieve comparable performances in the evaluation of suspected ventilator-associated pneumonia (VAP). We studied the impact of both approaches on outcome in a prospective, open, and randomized study in three intensive care units (ICUs) of a 1,000-bed tertiary care university hospital. Patients with suspected VAP were randomly assigned to noninvasive (Group 1) versus invasive (Group 2) investigation (tracheobronchial aspirates [TBAS] versus bronchoscopically retrieved protected specimen brush [PSB] and bronchoalveolar lavage [BAL]. Samples were cultured quantitatively, and BAL fluid (BALF) was examined for intracellular organisms (ICO) additionally. Initial empiric antimicrobial treatment was administered following the guidelines of the American Thoracic Society (ATS) and adjusted according to culture results (and ICO counts in Group 2). Outcome variables included length of ICU stay and mechanical ventilation as well as mortality. Overall, 76 patients (39 noninvasive, 37 invasive) were investigated. VAP was microbiologically confirmed in 23 of 39 (59%) and 23 of 37 (62%) (p = 0.78). There were no differences with regard to the frequencies of community-acquired and potentially drug-resistant microorganisms (PDRM). Antimicrobial treatment was changed in seven patients (18%) of Group 1 and 10 patients (27%) of Group 2 because of etiologic findings (including five of 17 with ICO = 2% (p = not significant [NS]). Length of ICU stay and mechanical ventilation were also not significantly different in both groups. Crude 30-d mortality was 31 of 76 (41%), and 18 of 39 (46%) in Group 1 and 14 of 37 (38%) in Group 2 (p = 0.46). Adjusted mortality was 16% versus 11% (p = 0.53), and mortality of microbiologically confirmed pneumonia 10 of 23 (44%) in both groups (p = 1.0). We conclude that the outcome of VAP was not influenced by the techniques used for microbial investigation.     

Role of Clostridium difficile infection in the relapse of ulcerative colitis

A case of nosocomial diarrhea by Clostridium difficile in an older woman with an old history of increasing stool frequency, is reported. Colonoscopy and biopsy was performed due to an incomplete response to vancomicyn, and the diagnosis of underlying ulcerative colitis was made. The incidence of Clostridium difficile infection associated with the relapse of ulcerative colitis is nearly 10%. In patients with ulcerative colitis, macroscopic pseudomembranes and the usual predisposing factors for Clostridium difficile infection, usually, are not present. It seems to exist a significant correlation between the severity of the relapse and Clostridium difficile. The specific treatment of the pseudomembranous colitis, in the majority of the cases, is sufficient for a correct control of relapse of ulcerative colitis.     

Protein tyrosine phosphatase 1B is impaired in skeletal muscle of diabetic Psammomys obesus

Protein tyrosine phosphatases (PTPases) have been suggested to modulate the insulin receptor signal transduction pathways. We studied PTPases in Psammomys obesus, an animal model of nutritionally induced insulin resistance. No changes in the protein expression level of src homology PTPase 2 (SHP-2) (muscle, liver) or leukocyte antigen receptor (LAR) (liver) were detected. In contrast, the expression level of PTPase 1B (PTP 1B) in the skeletal muscle, but not in liver, was increased by 83% in the diabetic animals, compared with a diabetes-resistant line. However, PTP 1B-specific activity (activity/protein) significantly decreased (50% to 56%) in skeletal muscle of diabetic animals, compared with both the diabetes-resistant line and diabetes-prone animals. In addition, PTP 1B activity was inversely correlated to serum glucose level (r = -.434, P < .02). These findings suggest that PTP 1B, though overexpressed, is not involved in the susceptibility to insulin resistance in Psammomys obesus and is secondarily attenuated by hyperglycemia or other factors in the diabetic milieu.