Age-related changes in brain: II. Positron emission tomography of frontal and temporal lobe glucose metabolism in normal subjects

While many neuropsychological studies have demonstrated age-related performance alterations in tests thought to reflect frontal and temporal lobe function, there is little direct observation and comparison of these hypothesized brain changesin vivo. The cerebral glucose metabolism of frontal, temporal, and cerebellar regions was examined in 40 young ( =27.5±4.9) and 31 elderly ( =67.6 ± 8.8) normal males using PET-FDG. Univariate analysis showed age-related metabolic reductions in all frontal and temporal lobe regions. The reductions ranged from 13%–24% with the greatest changes in the frontal lobes. Multiple regression analyses showed a stronger age relationship with frontal lobe than with temporal lobe metabolism. The dorsal lateral frontal lobe was the region that appears to change most within the frontal lobes. Examination of the temporal lobe showed that age contributed equally to the metabolic variance of both the lateral temporal lobe and hippocampus. These results suggest that age-related metabolic changes exist in both frontal and temporal lobes and that the frontal lobe change is greater.     

Aggressive Angiomyxoma of Inguinoscrotal Region Mimicking Inguinal Hernia: a Case Report

Aggressive angiomyxoma (AAM) is a rare mesenchymal tumour of pelvis and perineum, almost exclusively occurring in females. We are reporting a case of a 53-year-old gentleman who presented with a long standing inguinoscrotal swelling misdiagnosed as inguinal hernia, for which he underwent incomplete excision at local hospital and then was referred to our centre for completion surgery.     

Validation of the Fitbit Zip and Fitbit Flex with pregnant women in free-living conditions

Physical activity (PA) is a part of a healthy pregnancy. To date, no consumer-based activity monitors have been validated with this population. The aim of this study was to validate the Fitbit Zip and Fitbit Flex monitors in free-living conditions with pregnant women using the ActiGraph GT3X as the ?gold standard?. We compared the accuracy of the Fitbit Zip and Fitbit Flex devices in measuring steps, sedentary time and time spent in different activity intensities. Sixteen women in their third trimester of pregnancy wore the ActiGraph GT3X (hip) plus one Fibit Zip (hip) and one Fitbit Flex (wrist) during seven consecutive days. The validity of Fitbit Zip and Fitbit Flex is good, depending on measured parameters. Fitbit Zip is accurate to measure steps whereas Fitbit Flex is precise for MVPA. When choosing between Fitbit Zip and Fitbit Flex monitors, pregnant women should take into account their preferred PA and the parameters they want to measure..     

Histopathology and apoptosis in an animal model of reversible renal injury

High adenine phosphate (HAP) diet serves as an animal model of chronic renal failure (RF). Induction of RF and establishment of end organ damage require long exposure periods to this diet. Previously, we have shown that RF is reversible after diet cessation even after protracted administration. In this study, we explored the underlying renal changes and cellular pathways occurring during administration and after cessation of the diet. Kidneys were obtained from rats fed HAP diet for 7 weeks, and from rats fed HAP diet followed a 10 week recovery period on normal diet. The kidneys of HAP diet group were significantly enlarged due to tubular injury characterized by massive cystic dilatation and crystal deposition. Kidney injury was associated with markers of apoptosis as well as with activation of apoptosis related pathways. Diet cessation was associated with a significant reduction in kidney size, tubules diameter, and crystals deposition. The recovery from renal injury was coupled with regression of apoptotic features. This is the first study showing the potential reversibility of long standing RF model, allowing optimal evaluation of uremia-chronic effects.     

Screening of Nutritionally Important Gut Bacteria from the Lepidopteran Insects Through Qualitative Enzyme Assays

Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Lepidopteran insects are the most dominant and diversified group among phytophagous pests and economically...     

Amyloid and metabolic positron emission tomography imaging of cognitively normal adults with Alzheimer's parents

This study examines the relationship between fibrillar beta-amyloid (Aβ) deposition and reduced glucose metabolism, a proxy for neuronal dysfunction, in cognitively normal (NL) individuals with a parent affected by late-onset Alzheimer's disease (AD). Forty-seven 40–80-year-old NL received positron emission tomography (PET) with ¹¹C-Pittsburgh compound B (PiB) and 18F-fluoro-2-deoxy-d-glucose (FDG). These included 19 NL with a maternal history (MH), 12 NL with a paternal history (PH), and 16 NL with negative family history of AD (NH). Automated regions of interest, statistical parametric mapping, voxel-wise intermodality correlations, and logistic regressions were used to examine cerebral-to-cerebellar PiB and FDG standardized uptake value ratios across groups. The MH group showed higher PiB retention and lower metabolism in AD regions compared with NH and PH, which were negatively correlated in posterior cingulate, frontal, and parieto-temporal regions (Pearson r ≤ −0.57, p ≤ 0.05). No correlations were observed in NH and PH. The combination of Aβ deposition and metabolism yielded accuracy ≥ 69% for MH vs. NH and ≥ 71% for MH vs. PH, with relative risk = 1.9–5.1 (p values < 0.005). NL individuals with AD-affected mothers show co-occurring Aβ increases and hypometabolism in AD-vulnerable regions, suggesting an increased risk for AD.     

Embolus location affects the sensitivity of a rapid quantitative D-dimer assay in the diagnosis of pulmonary embolism

D-dimer blood tests have been suggested to rule out pulmonary embolism. Despite evidence of the safety of withholding anticoagulant treatment in patients with suspected pulmonary embolism and a normal D-dimer assay result, clinicians remain reluctant to use a D-dimer assay as a sole diagnostic test. This prospective study in 314 consecutive inpatients and outpatients investigates the relation between the diagnostic accuracy of D-dimer plasma concentration and pulmonary embolus location. Plasma D-dimer levels were measured using a quantitative immunoturbidimetric method. A strict protocol of ventilation-perfusion scintigraphy, pulmonary angiography, and spiral computed tomography was used to arrive at a final diagnosis and to assess the largest pulmonary artery in which embolus was visible. The influence of embolus location on the diagnostic accuracy was evaluated using the Kruskal-Wallis test and receiver operator characteristics (ROC) analysis. There was a strong correlation between plasma D-dimer concentration and embolus location (Kruskal-Wallis, p < 0.001). Thus, the assay showed greater accuracy in excluding segmental or larger emboli (sensitivity = 93%) than subsegmental emboli (sensitivity = 50%). D-dimer concentration and the accuracy of D-dimer assays are clearly dependent on embolus location and smaller, subsegmental emboli may be missed when D-dimer assays are used as a sole test to exclude pulmonary embolism.     

The performance of two rapid quantitative D-dimer assays in 287 patients with clinically suspected pulmonary embolism

Context: Objective tests are necessary for the diagnosis of pulmonary embolism (PE). D-dimer assays have been suggested as useful screening tests to exclude this diagnosis. Objective: To compare the diagnostic accuracy of two rapid quantitative D-dimers in patients with suspected pulmonary embolism. Design: Plasma D-dimer levels were measured using two commercially available assays (Tinaquant® and Vidas®). A strict imaging protocol was used to arrive at a final diagnosis of PE or deep venous thrombosis (DVT). Setting: Multicenter study in six Dutch referral centers. Patients: A total of 287 in- and outpatients with clinically suspected pulmonary embolism. Main outcome measures: Diagnostic accuracy indices for the two assays were calculated and additional receiver-operated characteristics (ROC) analysis was performed. Results: Using the manufacturer's advised cutoff values, the sensitivity and specificity were 88% and 52% for Vidas and 82% and 61% for Tinaquant, respectively. These differences were statistically significant (McNemar, P<0.0001). However, no statistical differences were found between the two assays using ROC analysis (AUC=0.78 for both assays). Conclusions: Both quantitative D-dimer tests had similar diagnostic accuracy; however, at the manufacturer's advised cutoff level, Vidas performed significantly better. Nevertheless, to safely exclude pulmonary embolism, D-dimer assays should be combined with other diagnostic tests.