Agreement of multislice CT angiography and MR angiography in assessing the degree of carotid artery stenosis in consideration of different methods of postprocessing

OBJECTIVE: We investigated the agreement of multislice computed tomography angiography (CTA) and magnetic resonance angiography (MRA) in the quantitative measurement of carotid artery stenosis. The dependency of the agreement of the chosen postprocessing procedures was also investigated. METHODS: Fifty consecutive symptomatic patients were included in this study. In all patients, a CTA was performed with a 16-slice CT scanner. Within 30 days, the extracranial vessels were examined using a combined time-of-flight and contrast-enhanced MRA. The CT data sets were used to calculate the degree of stenosis according to the North American Symptomatic Carotid Endarterectomy Trial, European Carotid Surgery Trial, and Common Carotid methods by means of the 1-mm thick, transverse raw data (RD), a sagittal maximum-intensity projection reconstruction, and sagittal multiplanar reconstruction. In addition, a semiautomated analysis was done using a specialized postprocessing software. For all combinations of postprocessing procedures and methods of calculating the degree of stenosis, the correlation coefficient and the agreement based on Bland/Altman plots were calculated. RESULTS: Eleven of the 100 primarily included carotid arteries could not be evaluated. The correlation coefficients for all combinations were comparable and lied in the interval between 0.932 and 0.787. The best correlation was found for the combination of RD/sagittal multiplanar reconstruction and ECST method. The evaluation of the agreement gave a systematic overestimation of CTA between 1.9% and 10.7% with a 95% confidence interval between +/-26.7% and +/-43.3%. With the semiautomated postprocessing software, additional 33 vessels could not be evaluated. The agreement of the calculated degrees of stenoses was worse than that of the planar procedures. CONCLUSIONS: CTA and MRA had a feasible agreement in measuring the degree of stenosis of the carotid arteries. The best result could be obtained for the evaluation of the RD and the NASCET method. In this case one has to take into account a systematic overestimation of CTA of 1.9%. The combination with an additional reconstructive postprocessing procedure did not improve the result but might be useful for the radiologist to identify the location of the closest narrowing.     

Chronic fatigue and indicators of long-term employment disability in psychosomatic inpatients

The major goal of this study was to determine indictors of long-term disability for psychosomatic inpatients with chronic fatigue syndrome. To this end, a cross-sectional study was performed with a random sample of patients (n=1000, response rate: 83.9%) at a psychosomatic inpatient clinic. 51.1% of the patients (n=429) reported intensely persistent exhaustion that had no logical relation to actual exertion. 159 (37.1%) patients in this group were disabled from working and these comprised the main target group of this study. Significantly more patients in the target group worked part time, were disabled for a disproportionately long period of time (50.9% of all were disabled for more than 6 months in the previous year), and felt stressed because of conflicts with their superiors and/or colleagues (in each case, P<0.01). While more frequent psychological comorbidity was not found, they reported physical complaints more often. It was not the patients fit for work who felt more burdened with chronic fatigue, but rather the employment-disabled, who were actually exposed to fewer demands. These patients had, in comparison with those fit to work, a stronger fixation on somatic complaints, inadequate perception of physical and psychic sensations, difficulties getting along with other people and in coping with a regular job (in each case, P<0.01). Prospective examination of these indicators could help detect predictor variables for long-term disability in chronic fatigue. Such predictors could contribute to timely social-medical assessment and treatment.     

Not left ventricular lead position,but the extent of immediate asynchrony reduction predicts long-term response to cardiac resynchronization therapy

Cardiac resynchronization therapy (CRT) is an effective treatment for a large subgroup of chronic heart failure patients. Various attempts to improve the high non-responder rate of 30 % by preoperative asynchrony assessment have failed. We hypothesized that superior response to CRT is correlated with greater acute reduction of asynchrony and that a concordant left ventricular (LV) lead is beneficial compared to a discordant lead. Hundred and eight consecutive CRT patients from our center were prospectively included. Clinical status and asynchrony parameters were assessed before, 1 day and 6 months after CRT implantation. Super-response was defined as an increase of the LV ejection fraction by ≥15 % and a decrease in LV end systolic volume (LVESV) by ≥30 %. When the criteria for super-response were not met, average response was given with a decrease of baseline LVESV ≥15 %. Sixty eight patients were classified as responders (63 %). Comparing super- (n = 19) and average (n = 49) responders, we found that greater acute reduction of LV asynchrony (change of asynchronous segments under CRT: ?1.3 vs. ?0.4, p < 0.05; decrease of LV intraventricular delay: ?34 ms vs. ?16 ms, p < 0.05) is associated with superior reverse remodeling after 6 months. Importantly, asynchrony parameters of super-, average and non-responders were almost identical at baseline. A concordant LV lead (n = 63) was not associated with improved LV reverse remodeling compared to a discordant lead (n = 28): LVEF: +8.6 % vs. +7.8 %, p = 0.91; LVESV: ?30.5 ml vs. ?23.8 mL, p = 0.84. A greater immediate reduction of LV asynchrony predicts superior response. Preoperative asynchrony parameters do not correlate with outcome. A concordant LV lead is not superior to a discordant lead.     

Impact of hip anatomical variations on the cartilage stress: A finite element analysis towards the biomechanical exploration of the factors that may explain primary hip arthritis in morphologically normal subjects

Background

Hip arthritis is a pathology linked to hip-cartilage degeneration. Although the etiology of this disease is not well defined, it is known that age is a determinant risk factor. However, hip arthritis in young patients could be largely promoted by biomechanical factors. The objective of this paper is to analyze the impact of some normal anatomical variations on the cartilage stress distributions numerically predicted at the hip joint during walking.

Methods

A three-dimensional finite element model of the femur and the pelvis with the most relevant axial components of muscle forces was used to simulate normal walking activity. The hip anatomical condition was defined by: neck shaft angle, femoral anteversion angle, and acetabular anteversion angle with a range of 110–130°, 0–20°, and 0–20°, respectively. The direct boundary method was used to simulate the hip contact.

Findings

The hydrostatic stress found at the cartilage and labrum showed that a ± 10° variation with respect to the reference brings significant differences between the anatomic models. Acetabular anteversion angle of 0° and femoral anteversion angle of 0° were the most affected anatomical conditions with values of hydrostatic stress in the cartilage near 5 MPa under compression.

Interpretation

Cartilage stresses and contact areas were equivalent to the results found in literature and the most critical anatomical regions in terms of tissue loads were in a good accordance with clinical evidence. Altogether, results showed that decreasing femoral or acetabular anteversion angles isolatedly causes a dramatic increase in cartilage loads.     

Proteasomal degradation of cytotoxic necrotizing factor 1-activated rac

The cytotoxic necrotizing factor 1 (CNF1) from Escherichia coli has been shown to activate members of the Rho family by deamidation of glutamine 63. This amino acid is essential for hydrolysis of GTP, and any substitution results in a constitutively active Rho. Activation of Rho induces the formation of stress fibers, filopodia, and membrane ruffles due to activation of RhoA, Cdc42, and Rac, respectively. Here we show that the level of endogenous Rac decreased in CNF1-treated HEK293 and HeLa cells. The amount of mRNA remained unaffected, leaving the possibility that Rac is subject to proteolytic degradation. Treatment of cells with lactacystin, an inhibitor of the 26S proteasome, protected Rac from degradation. We have previously shown that CNF1 activates the c-Jun N-terminal kinase (JNK) only transiently in HeLa cells (M. Lerm, J. Selzer, A. Hoffmeyer, U. R. Rapp, K. Aktories, and G. Schmidt, Infect. Immun. 67:496-503, 1998). Here we show that CNF1-induced JNK activation is stabilized in the presence of lactacystin. The data indicate that Rac is degraded by a proteasome-dependent pathway in CNF1-treated cells.     

Characterization of endoglin and Ki-67 expression in endothelial cells from benign and malignant lesions of the uterine cervix

Activation of endothelial cells is often associated with the cellular proliferation in vitro . CD105 is a more specific marker of activated endothelial cells from tumor vessels and Ki-67 is used to assess the proliferation status of both tumor and endothelial cells. The aim of the present study was to evaluate the status of endothelial cells using CD105 and Ki-67 immunohistochemistry in benign and malignant lesions of the uterine cervix. Double stain for CD105/Ki-67 in benign and malignant lesions of the uterine cervix showed that these two markers had divergent expression on endothelial cells from associated tumor blood vessels dependent on lesion type and proliferation status of tumor cells. Absence of CD105/Ki-67 coexpression in endothelial cells was correlated with histopathology of the uterine cervix lesions and tumor proliferative status. The present findings suggest that CD105 expression is an early event, specific for premalignant lesions of the uterine cervix, while endothelial proliferation assessed on Ki-67 combined with the lack of CD105 expression is often associated with invasive cervical carcinoma.     

Oncocytic lipoadenoma of the parotid gland: Immunohistochemical and cytogenetic analysis

Salivary gland oncocytic lipoadenoma is an exceptional benign tumor composed of mature adipose tissue associated with a mixture of oncocytes. We report a case of oncocytic lipoadenoma showing sebaceous differentiation, and provide a cytogenetic analysis, which has not yet been described. A 64-year-old male developed a left parotid gland, well-encapsulated tumor measuring 3.5×3 cm², showing mature fat cells associated with oncocytic changes of epithelial components. Immunohistochemistry showed a dual epithelial population with ductal (positivity for AE1/AE3, CK19, CK7 antibodies) and basal-cell (positivity for p63, CK14, CK5,6 antibodies) differentiation in oncocytic areas. Moreover, oncocytic cells were stained with anti-alpha-1 antichymotrypsin antibody and phosphotungstic acid–hematoxylin staining. Molecular cytogenetic analysis showed a translocation t(12;14), resulting in structural rearrangement of the region framing the HMGA2 gene at 12q14.3. Such alterations in HMGA2 have been described in both lipomas and pleomorphic adenomas of the salivary glands.     

VEGF expression and angiogenesis in oral squamous cell carcinoma: an immunohistochemical and morphometric study

Angiogenesis is involved in tumor progression of oral squamous cell carcinoma (OSCC). In this study, we have investigated by immunohistochemistry vascular endothelial growth factor (VEGF) expression in tumor cells and we have correlated VEGF expression to microvessel area, evaluated by using CD105 as a marker of endothelial cells, in bioptic specimens of 54 human OSCC. Results demonstrated that VEGF is highly expressed in OSCC tumor specimens when compared to pre-neoplastic and normal tissues, without differences between the edge and inside the tumor. Moreover, VEGF expression is reduced in poor differentiated OSCC tumors when compared to moderate and good differentiated forms, and tumor microvessel area is higher in tumors when compared to pre-neoplastic lesions and normal tissues. Finally, VEGF and CD105 may be considered as reliable markers of tumor angiogenesis and progression in OSCC, even if we did not demonstrate any correlation between VEGF expression, tumor microvascular area, clinical stage, and lymph node status.