Relative contributions of the cerebellar vermis and prefrontal lobe volumes on cognitive function across the adult lifespan

Recent research has revealed significant relationships between the vermian regions of the cerebellum and cognitive functions typically associated with prefrontal lobe function. These relationships are believed to be supported by anatomical connections between the distant brain regions. Recent evidence also suggests that age-related reductions in the posterior vermis are associated with age-related decline in frontal lobe cognitive functions, but these studies did not consider concomitant age-related atrophy of the prefrontal lobes. In the present study we addressed this issue by examining cognitive and structural MRI data obtained from 251 adults ranging in age from 18 to 79. Cognition was examined with a computerized cognitive battery and volumes of the cerebellar vermian regions and the prefrontal lobes were determined using quantitative morphometry. Results of the study revealed that both prefrontal and vermian volumes were smaller in older adults compared to younger adults, and both volumes correlated with cognitive performances in the older individuals. However, after controlling for prefrontal volume, the relationships between cognitive function and vermian volumes were eliminated, whereas prefrontal lobe volume remained significantly related to cognitive function after controlling for vermian volumes. These results suggest that while a reduction in cerebellar vermian volume does not significantly relate to normal age-related cognitive decline, prefrontal volume is significantly related to cognitive aging. Our results are consistent with the frontal aging hypothesis.     

Measurement and control of in-plane surface chemistry during the oxidation of H-terminated (111) Si

In-plane directional control of surface chemistry during interface formation can lead to new opportunities regarding device structures and applications. Control of this type requires techniques that can probe and hence provide feedback on the chemical reactivity of bonds not only in specific directions but also in real time. Here, we demonstrate both control and measurement of the oxidation of H-terminated (111) Si. Control is achieved by externally applying uniaxial strain, and measurement by second-harmonic generation (SHG) together with the anisotropic-bond model of nonlinear optics. In this system anisotropy results because bonds in the strain direction oxidize faster than those perpendicular to it, leading in addition to transient structural changes that can also be detected at the bond level by SHG.     

Human CMV infection induces 5-lipoxygenase expression and leukotriene B4 production in vascular smooth muscle cells

Leukotrienes (LTs) are powerful proinflammatory lipid mediators that may play a central role in cardiovascular diseases, including arteriosclerosis, myocardial infarction, and stroke. Owing to restricted expression of 5-lipoxygenase (5-LO), the enzyme required for their synthesis, LTs are almost exclusively produced by myeloid cells. Here, we report that human cytomegalovirus (HCMV) infection of human vascular smooth muscle cells (SMCs) increases 5-LO mRNA levels by up to 170-fold in a dose- and time-dependent manner. Infected cells expressed 5-LO protein, as shown by immunohistochemistry, enabling them to synthesize bioactive LTB(4). HCMV-infected vascular SMCs expressing 5-LO protein were readily detected in tissue samples from CMV-infected patients with inflammatory bowel disease or AIDS. Thus, pathogen-induced LT production in HCMV-infected tissues may contribute to local inflammation, consistent with the ability of HCMV to control cellular and immunological functions. HCMV-induced LT biosynthesis in SMCs offers a molecular mechanism to explain HCMV-induced pathogenesis in inflammatory diseases.     

Idiopathic granulomatous mastitis: a 25-year experience

BACKGROUND: Idiopathic granulomatous mastitis (IGM) is a rare, benign, chronic inflammatory condition of the breast that can mimic inflammatory breast cancer and periductal mastitis (PDM). Eighteen patients with a histopathologic diagnosis of IGM, seen over a period of 25 years, were retrospectively reviewed and compared with 133 patients with PDM and 100 normal patients. STUDY DESIGN: The unit's pathology database and clinic letters for this time period were used to identify patients who had presented with IGM. A retrospective review of the notes was used to extract reproductive factors, cigarette smoking habits, and ethnicities that were recorded at presentation. These were compared with data from a similar group of patients with PDM and a control group. RESULTS: All IGM patients were women. Median age was 36 years (range 18 to 67 years) compared with 52 years (range 20 to 77 years) for PDM patients (p < 0.001). Seventeen percent of IGM patients were smokers at the time of presentation, as compared with 60% of PDM patients (p < 0.001). Although parity was similar for all groups, 10 IGM patients (56%) had given birth in the last 5 years, compared with 6 (5%) PDM patients (p < 0.001) and 20 (20%) in the control group (p=0.0194). Two IGM patients had recurrences after pregnancy. The course of IGM varied from 11 to 105 weeks and was not affected by any treatment modalities. CONCLUSIONS: IGM patients are younger, have given birth more recently, and are less likely to be Caucasian as compared with PDM patients. IGM is not related to smoking and can recur. Treatment should be supportive.     

The RAP study,report 4: morphological and topographical characteristics of multifocal macular neovascularization type 3

Graefe's Archive for Clinical and Experimental Ophthalmology - To report on the morphological characteristics and regional distribution of multifocal macular neovascularization type 3 (mMNV3)....     

Robust electrocardiogram (ECG) beat classification using discrete wavelet transform

This paper presents a robust technique for the classification of six types of heartbeats through an electrocardiogram (ECG). Features extracted from the QRS complex of the ECG using a wavelet transform along with the instantaneous RR-interval are used for beat classification. The wavelet transform utilized for feature extraction in this paper can also be employed for QRS delineation, leading to reduction in overall system complexity as no separate feature extraction stage would be required in the practical implementation of the system. Only 11 features are used for beat classification with the classification accuracy of approximately 99.5% through a KNN classifier. Another main advantage of this method is its robustness to noise, which is illustrated in this paper through experimental results. Furthermore, principal component analysis (PCA) has been used for feature reduction, which reduces the number of features from 11 to 6 while retaining the high beat classification accuracy. Due to reduction in computational complexity (using six features, the time required is approximately 4 ms per beat), a simple classifier and noise robustness (at 10 dB signal-to-noise ratio, accuracy is 95%), this method offers substantial advantages over previous techniques for implementation in a practical ECG analyzer.