Radiological features of acute gastric volvulus in adult patients

ObjectiveTo evaluate the radiological features of acute gastric volvulus in adults and correlate these features with operative findings.Materials and MethodsThe clinical, radiological and operative findings of five adult patients (four males and one female with mean age of 50.4 years) who presented or referred to King Abdullah University hospital over 4 year’s period with symptoms of acute gastric volvulus were reviewed retrospectively. All patients underwent upper gastrointestinal barium study and two of them had computed tomographic (CT) scans preoperatively. The radiological features demonstrated on upper gastrointestinal barium exams and CT scans were analyzed and compared with operative findings.ResultsRadiological and operative findings revealed organo-axial gastric volvulus in all patients in our study. All of them had associated diaphragmatic defect or hiatal hernia. The upper gastrointestinal barium studies demonstrated the classic radiological features of organo-axial volvulus. CT done on two of our patients confirmed the diagnosis.ConclusionUpper gastrointestinal barium study is an accurate way to diagnose and characterize acute gastric volvulus in adult patients. CT scan can also be used to diagnose this clinical entity.     

Utilizing wavelet transform and support vector machine for detection of the paradoxical splitting in the second heart sound

Paradoxical splitting occurs when pulmonic valve (P2) closes before the aortic valve (A2). This causes second heart sound (S2) to be a single sound during inspiration and split during exhalation. Etiology delay in aortic closure: aortic stenosis, volume overload of left ventricle (LV), conduction defects in LV, and left bundle branch block (LBBB). In this article, a method was proposed in early detection of a reverse in the appearance of A2 and P2 within S2. This method is based on the time–frequency maps obtained with the continuous wavelet transform (CWT), namely, the Meyer wavelet. A number of patients with LBBB and others with fitted pacemakers were studied. The above method is combined with the support vector machine (SVM) and performance of this method is evaluated using classification accuracy (Ca), sensitivity (Se), specificity, positive, and negative predicted values. Results show that it is relatively easy to detect the reverse in A2 and P2 and the Ca and Se is 90.97 and 94.44%, respectively, for the sample of 42 patients whose data were collected from the Cardiology Department at Brighton and Sussex University Hospital in England.     

Neonatal hyperoxia causes pulmonary vascular disease and shortens life span in aging mice

Bronchopulmonary dysplasia is a chronic lung disease observed in premature infants requiring oxygen supplementation and ventilation. Although the use of exogenous surfactant and protective ventilation strategies has improved survival, the long-term pulmonary consequences of neonatal hyperoxia are unknown. Here, we investigate whether neonatal hyperoxia alters pulmonary function in aging mice. By 67 weeks of age, mice exposed to 100% oxygen between postnatal days 1 to 4 showed significantly a shortened life span (56.6% survival, n = 53) compared to siblings exposed to room air as neonates (100% survival, n = 47). Survivors had increased lung compliance and decreased elastance. There was also right ventricular hypertrophy and pathological evidence for pulmonary hypertension, defined by reduction of the distal microvasculature and the presence of numerous dilated arterioles expressing von Willebrand factor and α-smooth muscle actin. Consistent with recent literature implicating bone morphogenetic protein (BMP) signaling in pulmonary vascular disease, BMP receptors and downstream phospho-Smad1/5/8 were reduced in lungs of aging mice exposed to neonatal oxygen. BMP signaling alterations were not observed in 8-week-old mice. These data suggest that loss of BMP signaling in aged mice exposed to neonatal oxygen is associated with a shortened life span, pulmonary vascular disease, and associated cardiac failure. People exposed to hyperoxia as neonates may be at increased risk for pulmonary hypertension.     

Immunological functions of oxidized human immunoglobulin G in type 1diabetes mellitus: its potential role in diabetic smokers as a biomarker of elevated oxidative stress

The role of oxidized immunoglobulin G in type 1 diabetic smokers has been investigated in the present study. Human immunoglobulin G (IgG) was modified by reactive oxygen species (ROS). The binding characteristics of circulating autoantibodies in type 1 diabetes patients against native and modified IgG were assessed by direct binding ELISA. High degree of specific binding by 68.5% of patients sera towards ROS-modified IgG was observed in comparison to its native analogue (p< 0.05). In addition, diabetic smokers (n=28) were examined and the results were compared with diabetic non-smokers (n=26). Circulating antibodies of diabetic smokers showed substantially stronger binding to modified IgG as compared with the antibodies present in diabetic non-smokers (p< 0.05). Normal human sera (n=53) showed negligible binding with either antigen. Competitive inhibition ELISA reiterates the direct binding results. The increase in total serum protein carbonyl levels in the diabetic smokers was largely due to an increase in oxidized IgG. Diabetic smokers showed substantially higher carbonyl contents in sera as well as in purified IgG as compared with sera and IgG of diabetic non-smokers. Collectively, the oxidation of plasma proteins, especially IgG, might enhance oxidative stress in type 1 diabetes smokers.     

Transit time affects the community stability of Lactobacillus and Bifidobacterium species in an in vitro model of human colonic microbiotia

Retention time, which is analogous to transit time, is an index for bacterial stability in the intestine. Its consideration is of particular importance to optimize the delivery of probiotic bacteria in order to improve treatment efficacy. This study aims to investigate the effect of retention time on Lactobacilli and Bifidobacteria stability using an established in vitro human colon model. Three retention times were used: 72, 96, and 144 h. The effect of retention time on cell viability of different bacterial populations was analyzed with bacterial plate counts and PCR. The proportions of intestinal Bifidobacteria, Lactobacilli, Enterococci, Staphylococci and Clostridia populations, analyzed by plate counts, were found to be the same as that in human colonic microbiota. Retention time in the human colon affected the stability of Lactobacilli and Bifidobacteria communities, with maximum stability observed at 144 h. Therefore, retention time is an important parameter that influences bacterial stability in the colonic microbiota. Future clinical studies on probiotic bacteria formulations should take into consideration gastrointestinal transit parameters to improve treatment efficacy.     

Raman spectroscopy detects deterioration in biomechanical properties of bone in a glucocorticoid-treated mouse model of rheumatoid arthritis

Although glucocorticoids are frequently prescribed for the symptomatic management of inflammatory disorders such as rheumatoid arthritis, extended glucocorticoid exposure is the leading cause of physician-induced osteoporosis and leaves patients at a high risk of fracture. To study the biochemical effects of glucocorticoid exposure and how they might affect biomechanical properties of the bone, Raman spectra were acquired from ex vivo tibiae of glucocorticoid- and placebo-treated wild-type mice and a transgenic mouse model of rheumatoid arthritis. Statistically significant spectral differences were observed due to both treatment regimen and mouse genotype. These differences are attributed to changes in the overall bone mineral composition, as well as the degree of phosphate mineralization in tibial cortical bone. In addition, partial least squares regression was used to generate a Raman-based prediction of each tibia's biomechanical strength as quantified by a torsion test. The Raman-based predictions were as accurate as those produced by microcomputed tomography derived parameters, and more accurate than the clinically-used parameter of bone mineral density. These results suggest that Raman spectroscopy could be a valuable tool for monitoring bone biochemistry in studies of bone diseases such as osteoporosis, including tests of drugs being developed to combat these diseases.