Quantification of Pulmonary Inflammatory Processes Using Chest Radiography: Tuberculosis as the Motivating Application

The purpose of this work was to develop a quantitative method for evaluating the pulmonary inflammatory process (PIP) through the computational analysis of chest radiography exams in posteroanterior (PA) and lateral views. The quantification procedure was applied to patients with tuberculosis (TB) as the motivating application.A study of high-resolution computed tomography (HRCT) examinations of patients with TB was developed to establish a relation between the inflammatory process and the signal difference-to-noise ratio (SDNR) measured in the PA projection. A phantom essay was used to validate this relation, which was implemented using an algorithm that is able to estimate the volume of the inflammatory region based solely on SDNR values in the chest radiographs of patients.The PIP volumes that were quantified for 30 patients with TB were used for comparisons with direct HRCT analysis for the same patient. The Bland–Altman statistical analyses showed no significant differences between the 2 quantification methods. The linear regression line had a correlation coefficient of R² = 0.97 and P < 0.001, showing a strong association between the volume that was determined by our evaluation method and the results obtained by direct HRCT scan analysis.Since the diagnosis and follow-up of patients with TB is commonly performed using X-rays exams, the method developed herein can be considered an adequate tool for quantifying the PIP with a lower patient radiation dose and lower institutional cost. Although we used patients with TB for the application of the method, this method may be used for other pulmonary diseases characterized by a PIP.     

Dysfunction of mouse cerebral arteries during early aging

Aging leads to a gradual decline in the fidelity of cerebral blood flow (CBF) responses to neuronal activation, resulting in an increased risk for stroke and dementia. However, it is currently unknown when age-related cerebrovascular dysfunction starts or which vascular components and functions are first affected. The aim of this study was to examine the function of microcirculation throughout aging in mice. Microcirculation was challenged by inhalation of 5% and 10% CO₂ or by forepaw stimulation in 6-week, 8-month, and 12-month-old FVB/N mice. The resulting dilation of pial vessels and increase in CBF was measured by intravital fluorescence microscopy and laser Doppler fluxmetry, respectively. Neurovascular coupling and astrocytic endfoot Ca²⁺ were measured in acute brain slices from 18-month-old mice. We did not reveal any changes in CBF after CO₂ reactivity up to an age of 12 months. However, direct visualization of pial vessels by in vivo microscopy showed a significant, age-dependent loss of CO₂ reactivity starting at 8 months of age. At the same age neurovascular coupling was also significantly affected. These results suggest that aging does not affect cerebral vessel function simultaneously, but starts in pial microvessels months before global changes in CBF are detectable.     

“Obesity paradox” in coronary artery disease

Obesity used to be among the more neglected public health problems, but has unfolded as a growing medical and socioeconomic burden of epidemic proportions. Morbid obesity is linked to traditional cardiovascular risk factors like, hypertension, hyperlipidemia and diabetes, and suspected to incur increased morbidity and mortality in the Western and even third world populations. This patient cohort is also at greater risk to develop coronary artery disease. Recent population-based registries revealed that 43% and 24% of all cases of coronary revascularization were carried out in overweight and obese patients, respectively. However, despite evidence of a positive correlation between obesity and increased cardiovascular morbidity, some authors have described a better clinical outcome in overweight and obese patients, a phenomenon they coined “obesity paradoxon”. Thus, there is an ongoing debate in light of conflicting data and the possibility of confounding bias causing misconception and challenging the “obesity paradox”. In this review article we present the current evidence and throughly discuss the validity of the “obesity paradoxon” in a variety of clinical settings.     

Inhibition of carbohydrate hydrolyzing enzymes associated with type 2 diabetes and antioxidative properties of some edible seeds in vitro

This study sought to evaluate the antioxidant properties and effects of some edible wild seeds [Afzelia africana Sm. (AFZ), Cyperus esculentus L. (CYP), Eleusine coracana Gaertn. (ELE), Irvingia gabonensis (Aubry-Lecomte ex O’Rorke) Baill. (IRV), Monodora myristica Dunal. (MON) and Parinari curatellifolia Planch. ex Benth. (PAR)] on α-amylase and α-glucosidase activities. The phenolic content and antioxidant activities of aqueous extracts of the seeds as typified by 1,1-diphenyl-2 picrylhydrazyl (DPPH) and hydroxyl (OH) radicals scavenging abilities and inhibition of Fe²⁺-induced malondialdehyde (MDA) production in rat’s pancreas in vitro were also assessed. ELE had significantly (p < 0.05) higher total phenol content than the other seeds; however, AFZ had the highest flavonoid content. The extracts scavenged DPPH· and OH· in a dose-dependent manner with aqueous extracts of PAR having the highest DPPH· scavenging ability, while extracts from IRV had the highest OH· scavenging ability and inhibition of Fe²⁺-induced MDA production in rat’s pancreas. Furthermore, all the extracts inhibited α-amylase and α-glucosidase activities in a dose-dependent manner. The α-amylase inhibitory effect of MON (IC₅₀ = 0.48 mg/mL) was comparable to that of acarbose (IC₅₀ = 0.40 mg/mL), while the α-glucosidase inhibitory effect of AFZ (IC₅₀ = 0.45 mg/mL) was comparable to that of acarbose (IC₅₀ = 0.39 mg/mL). The results suggest the potential use of the seeds in the dietary management of blood glucose levels associated with type 2 diabetes.