Differential Influence of Carotid Stenosis and White Matter Disease on Motor and Cognitive Activation.

BACKGROUND: Cognitive and motor performance can be supported, especially in older subjects, by different types of brain activations, which can be accurately studied by functional magnetic resonance imaging (fMRI). Vascular risk factors (VRFs) are extremely important in the development of cognitive impairment, but few studies have focused on the fMRI cortical activation characteristics of healthy subjects with and without silent cerebrovascular disease including white matter hyperintensities (WMH) and carotid stenosis (CS) performing cognitive tasks. METHODS: Thirty-five volunteers with and without asymptomatic unilateral carotid stenosis above 70% and variable degrees of WMH underwent performance of a simple motor and cognitive task during an fMRI session. RESULTS: While the performance of the motor task resulted in a cortical activation dependent of age but not of WMH and carotid stenosis, performance of the cognitive task was accompanied by a significantly increased activation independently correlated with age, presence of WMH as well as of carotid stenosis. CONCLUSIONS: in this study, cognitive domains regulating attention and working memory appear to be activated with a pattern influenced by the presence of carotid stenosis as well as by white matter hyperintensities. The impairment of these cognitive abilities is of high relevance in Alzheimer's disease pathology. The fMRI pattern shown in patients with asymptomatic but significant carotid stenosis might be related to chronic cerebrovascular hypoperfusion, a critical pathophysiological mechanisms in AD. In these patients, carotid endoarterectomy should be considered also for AD prevention and might be recommended.

Non mass-like enhancement categories detected by breast MRI and histological findings.

OBJECTIVE: To correlate the different non masslike enhancement categories detected by Magnetic Resonance Imaging (MRI) and the corresponding histological findings. PATIENTS AND METHODS: Two experienced radiologists reviewed the MRI examinations of 94 patients presenting non mass-like enhancements who had performed histological evaluation. According to the BI-RADS (Breast Imaging Reporting and Data System) lexicon, non masslike enhancements were classified as focal, linear, segmental, regional, ductal and diffuse enhancements. We focused on segmental, regional and ductal patterns. RESULTS: Among the 94 patients, 52.1% showed a regional pattern, 27.7% a segmental pattern and 20.2% a ductal pattern of enhancement. Of the 49 patients showing a regional pattern, the histological diagnosis was ductal invasive carcinoma (DIC) in 28 cases, ductal carcinoma in situ (DCIS) in 4 cases, lobular invasive carcinoma (LIC) in 3 cases and a benign disease in 9 cases. Of the 26 patients showing a segmental pattern, the histological outcome was DIC in 10 cases, DCIS in 7 cases and a benign disease in 5 cases. Among the 19 patients showing a ductal pattern, the result was DIC in 4 cases, DCIS in 4 cases and a benign disease in 7 cases. In most cases DIC presented as a regional pattern, while DCIS showed a segmental pattern in 26.9%, a ductal pattern in 21.1% and a regional pattern in 8.2% of cases. CONCLUSIONS: Our findings about ductal and segmental enhancements agree with the literature. We found a high rate of DIC presenting as a regional enhancement, instead; thus, we recommend a more detailed diagnosis, especially when an homogeneous/heterogeneous and clumped internal enhancement pattern is present.

Skin thickening as unique pathologic sign of an inflammatory breast cancer: a case report and review of the literature.

We report the case of a 42-year-old woman with inflammatory cancer of the right breast treated with neoadjuvant chemotherapy, surgery, additional chemotherapy, and consolidative radiotherapy (RT), that has metastatized to the chest wall and presented a resumption of disease on the contralateral breast. Magnetic Resonance (MR), performed after the second phase's fourth round of additional chemotherapy, showed a modest reduction of scar metastases on the right and a contralateral anomalous skin thickening with high signal intensity in T2 weighted images (WI) with multiple mass-like enhancements located in a wide area of the central region at the union of higher quadrants. These findings were suggestive for resumption of contralateral disease; the biopsy confirmed an inflammatory breast cancer (IBC) infiltrating lobular type with high mitotic rate. A retrospective evaluation of the previous MR exam, performed 5 months before, was conducted: on the left side only a modest skin thickening was found as an early sign. A careful review of the literature has confirmed that skin thickening, increased density and clinical signs of inflammation are the most common findings in inflammatory cancer. We report the case of a patient affected by IBC whose unique early sign of resumption on the contralateral breast was skin thickening.

Species-specific selection on soil fungal population after olive mill waste-water treatment.

Soil was treated with olive mill waste water (OMW) in order to study the effect of this agriculture waste on soil fungal population. Changes in fungal composition were observed after soil pollution. In order to test OMW selective pressure, growth kinetics of Penicillium cyclopium, Scopulariopsis brevicaulis and Cladosporium cladosporioides were studied on solid media supplemented with different OMW concentrations. S. brevicaulis and C. cladosporioides did not grow at OMW concentration higher than 50%, while at concentrations lower than 50% a growth decrease was observed. Instead, P. cyclopium was able to actively grow at all concentrations of OMW tested. Therefore the OMW can influence and modify the soil fungal homeostasis.

The high activity of rat glutathione transferase 8-8 with alkene substrates is dependent on a glycine residue in the active site.

Rat glutathione transferase (GST) 8-8 displays high catalytic activity with alpha, beta-unsaturated carbonyl compounds, including lipid peroxidation products such as 4-hydroxyalkenals. The catalytic efficiency of the related class Alpha GST 1-1 is substantially lower with the same substrates. Chimeric enzymes were prepared by replacing N-terminal subunit 8 segments of different lengths (6, 25, or 100 residues) with corresponding sequences from subunit 1 using recombinant DNA techniques. The chimeric subunit r1(25)r8, containing 25 amino acid residues from subunit 1, had the same low activity with alkenal substrates as that displayed by subunit 1. Mutation of Ala-12 into Gly in r1(25)r8 gave rise to the high alkenal activity characteristic of subunit 8, showing the importance of amino acid residue 12 for the activity. However, other structural determinants are also essential, as demonstrated by the corresponding Ala-12-->Gly mutation in subunit 1, which did not afford high alkenal activity. The results show that a single point mutation in a GST subunit may give rise to a 100-fold increase in catalytic efficiency with certain substrates. Introduction of such mutations may have contributed to the biological evolution of GST isoenzymes with altered substrate specificities and may also find use in the engineering of GSTs for novel functions.